Guide to Subwoofer Calibration and Bass Preferences - Page 82 - AVS Forum | Home Theater Discussions And Reviews
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post #2431 of 2484 Old 06-27-2020, 03:52 PM
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Originally Posted by mthomas47 View Post
Thanks, Darth! I wasn't ahead of you at all this time. I saw your link, clicked on it, read the posts, and immediately gave Mike Lang a couple of "Likes". Then, I came back here and gave you one. Anything that makes it easier/faster to edit the Guide, and makes the overall navigation on AVS Forum better, is great news as far as I am concerned.

Now, I just have to hope that the Guide makes the transition to the new platform all in one piece, and with the links and attachments intact. The links alone constitute a lot of work, and I would hate to try to recreate them.

Regards,
Mike
Hi Mike,

While I am hoping the same, and think everything will go flawlessly.

Is there any way, you could copy and save the Guide to a file on your computer. To be on the prudent side, while not been very savvy on computer skills. I believe to copy and save something to a file directly on your computer, should save all those links and attachments.


Darth

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post #2432 of 2484 Old 06-27-2020, 04:28 PM
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Originally Posted by darthray View Post
Hi Mike,

While I am hoping the same, and think everything will go flawlessly.

Is there any way, you could copy and save the Guide to a file on your computer. To be on the prudent side, while not been very savvy on computer skills. I believe to copy and save something to a file directly on your computer, should save all those links and attachments.


Darth
Greetings Darth,

Just as a Heads-Up I just had to Copy & Paste a complete Super-Lengthy Post to WORD on my computer.
The reason I had to do that was Photobucket is Messed-Up and NOT loading New Images correctly.
Those New Pictures I needed in that Post.
So, I was able to Copy & Paste the Complete Post with All-Information including Color, bold, links etc. and it All-Saved !!!
I went back and Clicked on the Saved Document to Verify it was all Still-Totally Intact as I typed it and it was.

Terry
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post #2433 of 2484 Old 06-28-2020, 12:54 AM
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Greetings Darth,

Just as a Heads-Up I just had to Copy & Paste a complete Super-Lengthy Post to WORD on my computer.
The reason I had to do that was Photobucket is Messed-Up and NOT loading New Images correctly.
Those New Pictures I needed in that Post.
So, I was able to Copy & Paste the Complete Post with All-Information including Color, bold, links etc. and it All-Saved !!!
I went back and Clicked on the Saved Document to Verify it was all Still-Totally Intact as I typed it and it was.

Terry
Hi Terry,

While I was doing a few test drive myself, also using Microsoft WORD. I was also able to copy, including the links intact. Unfortunately, I could only copy so much and not the whole Guide. Perhaps, a Memory Stick would be a better way to go.

But I think, I now realize what Mike's fear could be. Not so much as copy the Guide with all it's links, but having those links no longer working after the transition is done. Since the new operating system, may no longer recognize them.

I am hoping for the best, since the folks who operate this forum are very smart and computer savvy. And positive a lot of thoughts was put into this change, to make sure everything go flawlessly.


Darth

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post #2434 of 2484 Old 06-28-2020, 04:51 AM
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Originally Posted by darthray View Post
Hi Mike,

While I am hoping the same, and think everything will go flawlessly.

Is there any way, you could copy and save the Guide to a file on your computer. To be on the prudent side, while not been very savvy on computer skills. I believe to copy and save something to a file directly on your computer, should save all those links and attachments.


Darth
Hi Darth,

Definitely a good a idea to make a hard copy, I would imagine the migration to the new AVS Web Interface would at first allow both sites to be open at the same time old+new, this would usually be a standard as there is unfortunately going to be bugs or issues that happen with a migration like this. Especially with a site of this size. There is no escaping this, so hopefully it goes smoothly with only minor issues to be resolved as this not a easy job.

Jim
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post #2435 of 2484 Old 06-28-2020, 06:01 AM - Thread Starter
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Originally Posted by darthray View Post
Hi Terry,

While I was doing a few test drive myself, also using Microsoft WORD. I was also able to copy, including the links intact. Unfortunately, I could only copy so much and not the whole Guide. Perhaps, a Memory Stick would be a better way to go.

But I think, I now realize what Mike's fear could be. Not so much as copy the Guide with all it's links, but having those links no longer working after the transition is done. Since the new operating system, may no longer recognize them.

I am hoping for the best, since the folks who operate this forum are very smart and computer savvy. And positive a lot of thoughts was put into this change, to make sure everything go flawlessly.


Darth

Hi Darth,

You hit the nail on the head with your second paragraph. I have made Word copies of the Guide before, and I will definitely do that again in order to retain as much of the content as possible. But, many of the links in the Guide, including all of the links which enable navigation from the Table of Contents to individual sections and subsections of the Guide, are unique to AVS.

Several years ago, before the Guide existed in its current format, AVS migrated to a different platform. It may have involved a return to Vertical-Scope. If I am remembering the circumstances correctly, a lot of links within AVS no longer operated after the migration.

If necessary, I believe that I will be able to recreate navigation links within the Guide, although the individual links are time-consuming to create. (They currently involve a specific "jumpto" format in the TOC, and a specific "aname" format in the relevant subsection.) But, if links to other threads, and to external articles, videos, etc, are lost it may take a lot of effort to ever recreate them.

@Mike Lang has told me more than once that posts in AVS were never intended to host something as long as the Guide, even when I divided it into Post 1 and Post 2. Perhaps the new platform will work much better in that regard, and perhaps most of the internal links can survive the migration. I'm going to cross my fingers, and hope for the best!

Regards,
Mike

GUIDE TO SUBWOOFER CALIBRATION AND BASS PREFERENCES

* The Guide linked above is a comprehensive guide to Audio & HT systems, including:
Speaker placements & Room treatments; HT calibration & Room EQ; Room gain; Bass
Preferences; Subwoofer Buyer's Guide: Sealed/ported; ID subs; Subwoofer placement.
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I don't know if this is relevant
a few members such as Austin Jerry with his REW and miniDSP guide prefer to retain control and provide a link to a shared folder in Dropbox
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Originally Posted by darthray View Post
Hi Terry,

While I was doing a few test drive myself, also using Microsoft WORD. I was also able to copy, including the links intact. Unfortunately, I could only copy so much and not the whole Guide. Perhaps, a Memory Stick would be a better way to go.

But I think, I now realize what Mike's fear could be. Not so much as copy the Guide with all it's links, but having those links no longer working after the transition is done. Since the new operating system, may no longer recognize them.

I am hoping for the best, since the folks who operate this forum are very smart and computer savvy. And positive a lot of thoughts was put into this change, to make sure everything go flawlessly.


Darth
Darth,

In my situation I was only Copying & Pasting 1-Post information but it is lengthy but nothing compared to what you speak of.
There is No-Way I would be able to recall exact wording in that post much less all the Color, Bold, Links etc.
Thank goodness I was able to stick it over in a Word Document totally intact ...........

Since Photobucket does not work on weekends.
I'm hoping they will see and respond to the E-Mail I sent with the description of what's happening when trying to Up-Load any New Image/Picture.

Terry
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post #2438 of 2484 Old 06-28-2020, 09:19 AM
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Originally Posted by mthomas47 View Post
Hi Darth,

You hit the nail on the head with your second paragraph. I have made Word copies of the Guide before, and I will definitely do that again in order to retain as much of the content as possible. But, many of the links in the Guide, including all of the links which enable navigation from the Table of Contents to individual sections and subsections of the Guide, are unique to AVS.

Several years ago, before the Guide existed in its current format, AVS migrated to a different platform. It may have involved a return to Vertical-Scope. If I am remembering the circumstances correctly, a lot of links within AVS no longer operated after the migration.

If necessary, I believe that I will be able to recreate navigation links within the Guide, although the individual links are time-consuming to create. (They currently involve a specific "jumpto" format in the TOC, and a specific "aname" format in the relevant subsection.) But, if links to other threads, and to external articles, videos, etc, are lost it may take a lot of effort to ever recreate them.

@Mike Lang has told me more than once that posts in AVS were never intended to host something as long as the Guide, even when I divided it into Post 1 and Post 2.
Perhaps the new platform will work much better in that regard, and perhaps most of the internal links can survive the migration. I'm going to cross my fingers, and hope for the best!

Regards,
Mike
Mike,

I also a few days ago contacted Mike Lang in regards to raising the now Limit of 30-Pictures per Post.
On my dedicated build thread I easily exceed the 30-Limit per Post.
I was hoping that 30 Pictures Limit could simply be removed like on Audio Aficionado as it has No-Limitation at all for number of pictures.
Mike L. said they were switching to a new software program and maybe that would No-Longer have any limitation.

Mike Lang also said in his response to me he had never seen a post with 30-pictures.
He also said that Super Lengthy post with text didn't do well with the current older software.


And guys I'm not trying to come across with any Sarcasm at all just saying to Mike I know what he's saying above on Limits ...........

Terry
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^^^

Thanks Darth, Lesmor, and Terry for the helpful comments and encouragement! "Super-lengthy" doesn't really even begin to describe the Guide. It's been a while since I printed-out a copy, but I believe that the Guide, which is currently divided into the first two posts, would be approximately 140 8 1/2" by 11" pages, single-spaced, with about 11-point font. In book form, I think it would closely resemble a fairly large college textbook.

It's been sort of a labor of love, if that doesn't sound too melodramatic, although at times it was also drudgery. And, I have never tried to make a dime from it, and don't ever intend to try. But, I also can't really see paying $20 a month for access to a shared folder in Dropbox. I want the Guide to be available more-or-less indefinitely on AVS, so I don't think that solution would be practical for me.

I didn't mind financially supporting AVS a little by joining the Gold Club. That seemed like an appropriate thing to do considering the valuable resource it provides. But, other than my time, which is definitely worth something to me, I don't see myself making any ongoing financial investments to maintain the Guide.

I will simply have to hope that, as a sticky thread, the actual Guide in Posts 1 and 2 will be deemed worthy of some programming attention, if that is necessary, in order to make as seamless a transfer as possible. After the changeover, I will try to do whatever repair or remediation which may be required.

Regards,
Mike

GUIDE TO SUBWOOFER CALIBRATION AND BASS PREFERENCES

* The Guide linked above is a comprehensive guide to Audio & HT systems, including:
Speaker placements & Room treatments; HT calibration & Room EQ; Room gain; Bass
Preferences; Subwoofer Buyer's Guide: Sealed/ported; ID subs; Subwoofer placement.
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Originally Posted by mthomas47 View Post
Hi Terry,

As you know, my response to your post is also a response to a PM you sent me. Is there a significant difference between the PB4000 and the PB16, and should you have gotten four PB16's instead of four PB4000's? My answer to that has several parts. In general, I always recommend that people buy the largest and most powerful subwoofer that they can afford and accommodate, and then add multiples of that subwoofer from there.

But, four PB4000's already offer you a lot of potential horsepower, so I honestly don't think you made a bad decision to go with the PB4000's. Frankly, I remember working a little hard to get you off the plan to buy four PB3000's, because I wanted you to have access to more <20Hz SPL and TR. And, now you have that <20Hz capability, if you are willing to access it.

Let me try to address your direct questions, though. First, yes there is a fairly significant difference between the two subs, but the greatest difference is below 30Hz. Second, knowing you as I do now, you should have gone ahead and gotten the more powerful PB16 subwoofers simply to prevent the "what if's" that are plaguing you a little bit now, even though you are happy with the PB4000's. Third, and most important, you aren't actually using the full sub-20Hz capabilities of your PB4000's right now, and you can make them operate much more like the PB16's if you want to.

This is something that I thought about suggesting to you several times, after you posted Chad's calibration comments and results. But, each time I hesitated, because I thought that you wouldn't want to second-guess the strategic decisions that you and Chad made, and because I didn't want to get into a lengthy back-and-forth discussion on the subject. (Just being honest here.)

But, since you are second-guessing the decision to not buy the lower-frequency PB16's, I will make the suggestion now. You should try operating your PB4000's in 16Hz Extended mode. Right now, you are operating them in the 20Hz Standard mode, and that is why your frequency response drops-off a cliff at 20Hz, in the graph you posted. The reason that the PB4000 cabinet is so much bigger than the PB3000 cabinet is to help the subwoofer hit higher volumes at lower frequencies. By using only the 20Hz mode, you are essentially strangling the low-frequency capability of your four big subs.

If you had only one or two PB4000's, it might be a good decision to operate in Standard 20Hz mode, in order to preserve more headroom at other frequencies. But, with four corner-loaded PB4000's, you have all the headroom at every frequency that you could ever use in that room. Now, you just need to explore the lower frequencies, and see if you like them. If you don't like them, then the PB16's would have offered you no practical advantage whatsoever over the PB4000's. The bigger cabinets (woofers, amps, etc) are designed to go lower, louder. Period!

If you want to try this, here is what you would do. You don't have to change Chad's calibration or Audyssey in any way. All, you have to do is to insert a port plug in any of the ports (the center port if you like the looks of that better) of each of the subs. One plug per sub. Then, using the SVS remote, or the controls on the front display of each sub, or the SVS app, change the mode from Standard to Extended on all four subs. That's it, you're done!

That will change the port tune of the subs to allow them to give you the <20Hz SPL and TR that you are currently missing. And, for action movies, I think you will find that it takes your system to another level. You might also decide to increase the volume on your subs by just a couple of decibels. That way, you won't lose anything noticeable above 20Hz, while gaining a lot more below 20Hz.

At 16Hz, there is an 8dB difference between Standard (20Hz) and Extended (16Hz) on those subs. That would be like going from 4 PB4000's to a little more than 8 PB4000's. And, the PB4000's, in Extended mode, will continue to play deeper into the low-teens, where the Standard mode rolls-off hard just below 20Hz. You said that Chad had experience with your subs, and that's good! But, you also said that he wasn't accustomed to having four of them, in corner locations, to work with.

That's the difference! You already have headroom to spare. Now, you just need to let those four PB4000's out of their cages to see what they can do. Since you like sports cars, I will use a car analogy. You have restricted the fuel flow and gearing on your new sports car to keep it from achieving the horsepower, torque, and acceleration that you bought it for. But, it is an easy fix that will take you about 15 minutes to accomplish. And, you won't change or impair Audyssey's operation, in any way, by doing this.

I have tried to make this post very thorough to forestall additional questions. I hope it works!

Regards,
Mike


PS: I have assumed that you will enjoy the 16Hz Extended mode even more than you like the way the subs are operating now. And, I believe that will be the case for movies. You may not notice much difference for music or for some TV shows. But, if you ever decide that you want to return to the Standard mode that you are using now, then you simply remove the port plugs and change to Standard mode in the menu of each sub.

Again, there will be no effect whatsoever on the Audyssey EQ that was performed, when you change modes from Standard to Extended, and then back again to Standard. The Extended mode simply allows the sub to go lower, and lets you take advantage of any room gain that you might be getting, while the Standard mode prevents the sub from going as low in frequency and preserves more SPL above 20Hz.

But, where you already have ample headroom at every frequency, you can have more SPL above 20Hz by simply increasing your sub volume by a decibel or two. So, you can have ample loudness at other frequencies, while also taking advantage of the SPL and TR below 20Hz, when you use the Extended mode. For many on AVS, the use of sufficiently powerful low-tuned subs constitutes having your cake and eating it too.
Mike,

I have now Posted my reply buddy just Left-Click on the link below,

https://www.avsforum.com/forum/15-ge...l#post59873576


Thank-You as always,
Terry
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post #2441 of 2484 Old 06-28-2020, 12:35 PM
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Hi Mike I certainly didn't think that Dropbox would involve you having to pay a fee or I would not have suggested it
my Dropbox account is free and I can allow anyone to access a link to a shared folder and its content

I may be wrong but I would be surprised if Austin Jerry is paying a monthly fee just so that members could access his guides
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Originally Posted by mthomas47 View Post


@Mike Lang has told me more than once that posts in AVS were never intended to host something as long as the Guide, even when I divided it into Post 1 and Post 2. Perhaps the new platform will work much better in that regard, and perhaps most of the internal links can survive the migration. I'm going to cross my fingers, and hope for the best!

Regards,
Mike
Hi Mike,

Since I am sure that Terry, Jim and I. Are not the only one's crossing their fingers and hoping for the best as you do
I also now see that @Lesmor is also trying to help, and who knows how many silent members that also hope for the best for you.

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Mike,

I have now Posted my reply buddy just Left-Click on the link below,

https://www.avsforum.com/forum/15-ge...l#post59873576

Thank-You as always,
Terry
Hi Terry,

I see you got hit with the bug, not the covid19 one but the "What If" one
All I can say, is congratulation. And you did outstanding work and research in your room. It look amazing, with lots of nice gears!!!

Thanks friend, for sharing this info and a link of your Theater built in your Signature.


Darth
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Hi Mike,

Just thought to let you know, even if I was done with my settings on the subs.

Previously as you know, I decided to settle on a +2dB overall increase after calibration. And also using a +3dB value with 60Hz as the middle point with the maximum bandwidth, from my PEQ option on my new subs to increase my chest slam effect. And cannot go lower than the 18Hz setting due to room vibrations problems, even if my subs can go down to 12Hz.

While I was very satisfied, lately in the last 10 movies or so. I had the itch to try increasing my bass volume from the calibration readings, to see how it sound. Since a few weeks ago, my Wife and I watch the first John Wick. We decided to watch JW2 tonight, and increase previously to start the movie with an 0.5dB increase. Before the tunnel scene, I did another 0.5dB increase. Resulting in a total +3dB from the calibration results, while also keeping the extra +3dB from the PEQ curve. So far, so good from this movie.

This lead me to this question. When someone ask me "how hot" I do run my subs, is the answer. +3dB (keeping those last adjustment, from calibration level), or +6dB to also include the other extra boost from the PEQ?

While very technical, I would love your thoughts on this one. Since I am not sure how to answer this one, without a full previous history of my situation


Darth
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Hi Mike,

Just thought to let you know, even if I was done with my settings on the subs.

Previously as you know, I decided to settle on a +2dB overall increase after calibration. And also using a +3dB value with 60Hz as the middle point with the maximum bandwidth, from my PEQ option on my new subs to increase my chest slam effect. And cannot go lower than the 18Hz setting due to room vibrations problems, even if my subs can go down to 12Hz.

While I was very satisfied, lately in the last 10 movies or so. I had the itch to try increasing my bass volume from the calibration readings, to see how it sound. Since a few weeks ago, my Wife and I watch the first John Wick. We decided to watch JW2 tonight, and increase previously to start the movie with an 0.5dB increase. Before the tunnel scene, I did another 0.5dB increase. Resulting in a total +3dB from the calibration results, while also keeping the extra +3dB from the PEQ curve. So far, so good from this movie.

This lead me to this question. When someone ask me "how hot" I do run my subs, is the answer. +3dB (keeping those last adjustment, from calibration level), or +6dB to also include the other extra boost from the PEQ?

While very technical, I would love your thoughts on this one. Since I am not sure how to answer this one, without a full previous history of my situation

Darth

Hi Darth,

I'm glad that you're still experimenting with settings, and finding slightly different combinations that you like. I would say that you are running your subs +3dB hot, post-calibration. The PEQ boost of +3dB, centered on 60Hz, is for such a limited frequency range that I wouldn't really characterize it in the same way that I would your full-range subwoofer boost of +3dB.

Personally, I would describe it in just the way that you did in your post. You are running your subs +3dB hot, with a +3dB PEQ boost at 60Hz.

Regards,
Mike
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GUIDE TO SUBWOOFER CALIBRATION AND BASS PREFERENCES

* The Guide linked above is a comprehensive guide to Audio & HT systems, including:
Speaker placements & Room treatments; HT calibration & Room EQ; Room gain; Bass
Preferences; Subwoofer Buyer's Guide: Sealed/ported; ID subs; Subwoofer placement.
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Originally Posted by darthray View Post
Is there any way, you could copy and save the Guide to a file on your computer. To be on the prudent side, while not been very savvy on computer skills. I believe to copy and save something to a file directly on your computer, should save all those links and attachments.

Quote:
Originally Posted by mthomas47 View Post
You hit the nail on the head with your second paragraph. I have made Word copies of the Guide before, and I will definitely do that again in order to retain as much of the content as possible. But, many of the links in the Guide, including all of the links which enable navigation from the Table of Contents to individual sections and subsections of the Guide, are unique to AVS.
I too save a Word copy of every article I publish, along with the HTML code from the post itself. That way I have two different ways to import/edit/update in case something goes awry with the original version (like what happened on HTS when they switched to a cloud provider and lost every picture and graph I had ever posted in a review).

 
If you take yourself too seriously expect me to do the exact opposite.

BTW, did you really need to quote the entire post?
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Quote:
Originally Posted by darthray View Post
Hi Terry,

I see you got hit with the bug, not the covid19 one but the "What If" one
All I can say, is congratulation. And you did outstanding work and research in your room. It look amazing, with lots of nice gears!!!

Thanks friend, for sharing this info and a link of your Theater built in your Signature.


Darth


Hi Darth,

I will be doing a very-very extensive post once I can get all the necessary pictures taken.
I'm waiting on some addition gear that's been ordered by "Wolf-Hill-Technologies" to arrive.
Then they can come and complete for now the H/T changes.
There are over 100 pictures I'll be posting of all those changes.

Regards,
Terry
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post #2448 of 2484 Old 06-29-2020, 05:44 PM
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Hi Darth,

I will be doing a very-very extensive post once I can get all the necessary pictures taken.
I'm waiting on some addition gear that's been ordered by "Wolf-Hill-Technologies" to arrive.
Then they can come and complete for now the H/T changes.
There are over 100 pictures I'll be posting of all those changes.

Regards,
Terry
Hi Terry,

Since you have so many pictures, post them on your Built Thread.
https://www.avsforum.com/forum/15-ge...l#post59873576
And let us know when it's done, so we know to go take a look at them.

Looking forward to see all your changes


Darth
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Originally Posted by darthray View Post
Hi Terry,

Since you have so many pictures, post them on your Built Thread.
https://www.avsforum.com/forum/15-ge...l#post59873576
And let us know when it's done, so we know to go take a look at them.

Looking forward to see all your changes


Darth
Darth,

That will be where the pictures are going.
I'm on Hold-Currently waiting on the rest of the audio gear to arrive so I can complete the remaining pictures.
Once that's arrived and the techs come and complete the installs and also while here remove the current 4 SVS PB-4000 Subs to the Formal-Living-Room for Best Buy to Pick-Up when they bring the 4 SVS PB-16 ULTRAS.
Plus ship the JVC RS4500 laser projector to CA for repair.
Then while the RS4500 is being repaired by JVC in CA more than likely the New 4 SVS PB-16 ULTRA subwoofers will come in and get delivered to me.
So, if things do fall into place my guys will rehang the RS4500 and do the initial install of the PB-16 ULTRA subs at the same-time so I don't have to foot the Labor-Cost for multiple trips.

Lastly, regarding the above ^^^ Chad B and I have a plan/agreement on his returning to do Both the Audio & Video Custom Calibrating.
(This next time I won't be telling Chad what to do and not to do on the Calibrating that's for sure)

One just has to stay calm and not get over excited while things fall into place overtime ............

Terry

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Howdy Mike,
In the past you have mentioned calibrating in standard mode with PB16s then switching to extended, thoughts on calibrating in sealed mode to preserve more room gain from 20-25hz followed by switching to extended?

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Howdy Mike,
In the past you have mentioned calibrating in standard mode with PB16s then switching to extended, thoughts on calibrating in sealed mode to preserve more room gain from 20-25hz followed by switching to extended?

Hi Matt,

I think that might mess-up your frequency response, below about 40 or 50Hz. Audyssey stops EQing where subwoofers roll-off naturally in the room, by -3dB. With sealed subs, that would happen at a much higher frequency than it would with ported subs, and you would lose the benefit of any EQ below that natural roll-off.

The natural roll-off would also happen at a much higher frequency than where meaningful room gain would start. And, of course, the EQ would be quite different even above the frequency where the natural -3dB roll-off occurred. Most people can usually have enough 20Hz to 25Hz SPL without doing something like this. It's the <20Hz SPL that is harder to obtain.

The strength of EQing in Standard mode, and then switching to Extended mode, is that nearly all of of the difference between the two modes would occur where the room gain would be the strongest---below 20Hz. The frequency response of the two ported modes would be pretty similar down to 20Hz (within about a couple of decibels), and it would only be below 20Hz that the Standard mode would drop away so fast, due to the high-pass filter with a 32dB per octave roll-off, that SVS uses.

Starting in Standard mode keeps Audyssey from potentially EQing away any <20Hz room gain, so that when you switch to Extended mode you should be able to get even more SPL in the high to mid-teens. And, that's where most people really want the extra oomph for low-bass scenes.

You could always experiment with the method that you are suggesting, but I suspect that you will have a much more uneven frequency response, below about 40 or 50Hz, that way. Still, it doesn't cost anything to try it, and to measure and to listen to the results. If you do decide to try it, let me know what you discover.

Regards,
Mike

GUIDE TO SUBWOOFER CALIBRATION AND BASS PREFERENCES

* The Guide linked above is a comprehensive guide to Audio & HT systems, including:
Speaker placements & Room treatments; HT calibration & Room EQ; Room gain; Bass
Preferences; Subwoofer Buyer's Guide: Sealed/ported; ID subs; Subwoofer placement.
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Hi Matt,

I think that might mess-up your frequency response, below about 40 or 50Hz. Audyssey stops EQing where subwoofers roll-off naturally in the room, by -3dB. With sealed subs, that would happen at a much higher frequency than it would with ported subs, and you would lose the benefit of any EQ below that natural roll-off.

The natural roll-off would also happen at a much higher frequency than where meaningful room gain would start. And, of course, the EQ would be quite different even above the frequency where the natural -3dB roll-off occurred. Most people can usually have enough 20Hz to 25Hz SPL without doing something like this. It's the <20Hz SPL that is harder to obtain.

The strength of EQing in Standard mode, and then switching to Extended mode, is that nearly all of of the difference between the two modes would occur where the room gain would be the strongest---below 20Hz. The frequency response of the two ported modes would be pretty similar down to 20Hz (within about a couple of decibels), and it would only be below 20Hz that the Standard mode would drop away so fast, due to the high-pass filter with a 32dB per octave roll-off, that SVS uses.

Starting in Standard mode keeps Audyssey from potentially EQing away any <20Hz room gain, so that when you switch to Extended mode you should be able to get even more SPL in the high to mid-teens. And, that's where most people really want the extra oomph for low-bass scenes.

You could always experiment with the method that you are suggesting, but I suspect that you will have a much more uneven frequency response, below about 40 or 50Hz, that way. Still, it doesn't cost anything to try it, and to measure and to listen to the results. If you do decide to try it, let me know what you discover.

Regards,
Mike
Will do, thanks! Going off the link on SVS it looks like the outdoor response is flat to a little below 30hz even for sealed for the pb16s, so I will try it I think, I actually have to order the plugs since I only got two. Thanks!

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LFE: 2x SVS PB 16 Ultras/2x Crowson MAs
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Hopefully @MThomas can answer this since I am going back through and re-reading the guide and I need clarification from the writer himself. Mr. Thomas, you briefly mention that it may be better to use your calibration 8 mic positions that do not go back behind the chairs, but do not mention why you feel that going behind the chairs shouldn't be done? The couch downstairs that has the Audyssey XT32 (using mobile app) has 4 chairs side by side in 1 row. Can you please expand on this on why it is not beneficial to do mic measurements behind the couch? I know you said to do trial and error (like everything else in this hobby), but I would like an explanation on this aspect please. I have done measurements using your calibration technique and also measurements the standard way that Audyssey wants it done, but do not discern too much of a difference in my room, especially since the distances/timings, etc are all based off of Mic position 1.

Thanks in advance, Mike!
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Hopefully @MThomas can answer this since I am going back through and re-reading the guide and I need clarification from the writer himself. Mr. Thomas, you briefly mention that it may be better to use your calibration 8 mic positions that do not go back behind the chairs, but do not mention why you feel that going behind the chairs shouldn't be done? The couch downstairs that has the Audyssey XT32 (using mobile app) has 4 chairs side by side in 1 row. Can you please expand on this on why it is not beneficial to do mic measurements behind the couch? I know you said to do trial and error (like everything else in this hobby), but I would like an explanation on this aspect please. I have done measurements using your calibration technique and also measurements the standard way that Audyssey wants it done, but do not discern too much of a difference in my room, especially since the distances/timings, etc are all based off of Mic position 1.

Thanks in advance, Mike!

Hi,

I will have to go back to reread what I wrote, but I believe that I did explain why it probably isn't typically a good idea to go behind your main listening position with any of your microphone measurements during calibration. It's because no one is actually listening back there, and we typically want to EQ where we are listening. I use words like "probably" and "typically" in most of my advice and explanations because I believe that it's better to generalize, rather than to speak in absolute terms, when we talk about this sort of thing.

For instance, you said that you have tried it both ways and can't really measure much difference. I would be curious whether you can hear any difference, because those are two different things. But, I will leave that alone for a moment. I think that, in many cases, individual listeners might be able to hear a difference. And the general theory of going behind your chair with some mic positions, when no one is actually sitting there, just doesn't make any sense to me.

We know from long experience with Audyssey, that Audyssey usually (another generalization) works best when we keep the microphone pattern fairly compact. Even Audyssey came to realize that over time, and now recommends a much smaller microphone spacing than they did 6-8 years ago. The reason for that is the fuzzy-logic weighting system that Audyssey uses to average the results of the measurements from multiple (usually 8) microphone positions. The more we prevent anomalous measurements of random peaks and valleys from skewing the average, the better room EQ we generally get.

So, we try to concentrate our measurements in the area of the most important listening position(s), knowing that we can't realistically EQ the entire room. From long observation of Audyssey results, I would say that the larger area we attempt to EQ, the more likely Audyssey is to degrade our sound quality at the MLP (main listening position) rather than to improve it. So, we try to keep our measurement mic at about ear height, because that is where we are actually listening, and we try to keep the measurement microphone fairly close to just one, or at the most two, listening positions.

How does all of that relate to going behind a listening position with a couple of measurements? Well, why would we do that, if there is no one listening back there? Wouldn't that be more likely to generate exactly the kind of anomalous measurement information that we were trying to avoid? At best, it would be pretty unlikely to help, and at worst we would be much more likely to pick-up reflections from other surfaces (such as walls) behind our listening position.

This is one of those instances where owner's manuals are trying to cover every possibility, such as home theaters with multiple listening rows. And, as a result of trying to cover every possibility, they give bad advice to almost everyone. I think that the advice they give to everyone, to use two mic positions behind the main listening positions, is likely to end-up doing more harm than good. And, anecdotal reports from a number of users, in the form of both measurements and listening experiences, have tended to support that.

I also think that user manuals are rarely written by the engineers who actually designed the products. And, this is like the advice that Audyssey manuals used to give to keep measurements at least 3-4' apart. Users who followed that advice very often found themselves with relatively poor sound quality at the MLP.

The final thing that I will say about this is that measurements don't always provide an essential correlation to what we actually hear, even if we are fairly sophisticated at looking at FR graphs and impulse responses. For instance, a relatively modest looking boost at higher frequencies may translate into a shriller sound at some treble frequencies. The same thing is true for a very busy looking treble response.

We can often see a very jagged high-frequency response when we get the Audyssey microphone too close to a reflective surface, such as a seat back. That's why we have learned to put something absorbent over the seat back, during calibration. And, it is mostly higher frequencies that I would worry about, if I measured behind my listening position, because the higher frequencies are so dependent on reflections from any surfaces in the room. (I have also seen reports and measurements demonstrating that low-frequencies were adversely affected by measuring behind the MLP during calibrations.)

The Audyssey omnidirectional microphone can pick-up both early and late reflections, of high-frequencies, in a way that will influence the room EQ that it performs. And yet, our brains would often have ignored some of those early and late reflections that Audyssey "heard", and which it tried to "correct". In those cases, an unnecessary correction can actually degrade the sound quality. The Audyssey microphone and our brains simply don't "hear" sounds in the same way. The better we understand that fact, the better we can help Audyssey (or other forms of room EQ) to help us to achieve improved sound quality.

As a side note, I believe that the issue of high-frequency reflections, occurring at different points in space, is why some people end-up choosing not to use Audyssey (or other forms of room EQ) above certain frequencies. Depending on the room, and the speakers involved, it can sometimes take a fairly sophisticated effort to get a good full-range calibration. And, for some people, the full-range calibration might never be as satisfactory for them. YMMV again!

Ultimately, where room EQ is concerned, I believe that we all have to trust our ears, and our brains, which significantly influence what we hear. If a particular calibration (or setting) sounds better to us, then it is better, because our real goal is improved sound quality. If we really can't hear any difference between two calibrations, then by definition, there really isn't any meaningful difference where we are concerned.

Having said all of that, it is easy to understand why I consider so many of these questions to have a strong YMMV component. Different people, in different rooms, with different systems, will hear different things. The most that the Guide can do is to provide generalized advice. And then, it it up to individuals to decide if that advice is applicable to their specific circumstances. Measuring behind the MLP, during an Audyssey calibration, is a good example of that.

Not exactly how I had envisioned spending my 4th of July morning, but oh well!

Regards,
Mike


Edit: I decided to provide a link to this post in Section I-B of the Guide. That way, people who are interested in having more detail, on why it may not be advisable to calibrate behind our listening chairs, can read the above explanation.

GUIDE TO SUBWOOFER CALIBRATION AND BASS PREFERENCES

* The Guide linked above is a comprehensive guide to Audio & HT systems, including:
Speaker placements & Room treatments; HT calibration & Room EQ; Room gain; Bass
Preferences; Subwoofer Buyer's Guide: Sealed/ported; ID subs; Subwoofer placement.

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Hi,

I will have to go back to reread what I wrote, but I believe that I did explain why it probably isn't typically a good idea to go behind your main listening position with any of your microphone measurements during calibration. It's because no one is actually listening back there, and we typically want to EQ where we are listening. I use words like "probably" and "typically" in most of my advice and explanations because I believe that it's better to generalize, rather than to speak in absolute terms, when we talk about this sort of thing.

For instance, you said that you have tried it both ways and can't really measure much difference. I would be curious whether you can hear any difference, because those are two different things. But, I will leave that alone for a moment. I think that, in many cases, individual listeners might be able to hear a difference. And the general theory of going behind your chair with some mic positions, when no one is actually sitting there, just doesn't make any sense to me.

We know from long experience with Audyssey, that Audyssey usually (another generalization) works best when we keep the microphone pattern fairly compact. Even Audyssey came to realize that over time, and now recommends a much smaller microphone spacing than they did 6-8 years ago. The reason for that is the fuzzy-logic weighting system that Audyssey uses to average the results of the measurements from multiple (usually 8) microphone positions. The more we prevent anomalous measurements of random peaks and valleys from skewing the average, the better room EQ we generally get.

So, we try to concentrate our measurements in the area of the most important listening position(s), knowing that we can't realistically EQ the entire room. From long observation of Audyssey results, I would say that the larger area we attempt to EQ, the more likely Audyssey is to degrade our sound quality at the MLP (main listening position) rather than to improve it. So, we try to keep our measurement mic at about ear height, because that is where we are actually listening, and we try to keep the measurement microphone fairly close to just one, or at the most two, listening positions.

How does all of that relate to going behind a listening position with a couple of measurements? Well, why would we do that, if there is no one listening back there? Wouldn't that be more likely to generate exactly the kind of anomalous measurement information that we were trying to avoid? At best, it would be pretty unlikely to help, and at worst we would be much more likely to pick-up reflections from other surfaces (such as walls) behind our listening position.

This is one of those instances where owner's manuals are trying to cover every possibility, such as home theaters with multiple listening rows. And, as a result of trying to cover every possibility, they give bad advice to almost everyone. I think that the advice they give to everyone, to use two mic positions behind the main listening positions, is likely to end-up doing more harm than good. And, anecdotal experience in the form of both measurements, and listening, have tended to support that.

I also think that user manuals are rarely written by the engineers who actually designed the products. And, this is like the advice that Audyssey manuals used to give to keep measurements at least 3-4' apart. Users who followed that advice very often found themselves with relatively poor sound quality at the MLP.

The final thing that I will say about this is that measurements don't always provide an essential correlation to what we actually hear, even if we are fairly sophisticated at looking at FR graphs and impulse responses. For instance, a relatively modest looking boost at higher frequencies may translate into a shriller sound at some treble frequencies. The same thing is true for a very busy looking treble response.

We can often see a very jagged high-frequency response when we get the Audyssey microphone too close to a reflective surface, such as a seat back. That's why we have learned to put something absorbent over the seat back, during calibration. And, it is mostly higher frequencies that I would worry about, if I measured behind my listening position, because the higher frequencies are so dependent on reflections from any surfaces in the room. (I have also seen low-frequencies adversely affected by going behind the MLP.)

The Audyssey omnidirectional microphone can pick-up both early and late reflections, of high-frequencies, in a way that will influence the room EQ that it performs. And yet, our brains would often have ignored some of those early and late reflections that Audyssey "heard", and which it tried to "correct". In those cases, an unnecessary correction can actually degrade the sound quality. The Audyssey microphone and our brains simply don't "hear" sounds in the same way. The better we understand that fact, the better we can help Audyssey (or other forms of room EQ) to help us to achieve improved sound quality.

As a side note, I believe that the issue of high-frequency reflections, occurring at different points in space, is why some people end-up choosing not to use Audyssey (or other forms of room EQ) above certain frequencies. Depending on the room, and the speakers involved, it can sometimes take a fairly sophisticated effort to get a good full-range calibration. And, for some people, the full-range calibration might never be as satisfactory for them. YMMV again!

Ultimately, where room EQ is concerned, I believe that we all have to trust our ears, and our brains, which significantly influence what we hear. If a particular calibration (or setting) sounds better to us, then it is better, because our real goal is improved sound quality. If we really can't hear any difference between two calibrations, then by definition, there really isn't any meaningful difference where we are concerned.

Having said all of that, it is easy to understand why I consider so many of these questions to have a strong YMMV component. Different people, in different rooms, with different systems, will hear different things. The most that the Guide can do is to provide generalized advice. And then, it it up to individuals to decide if that advice is applicable to their specific circumstances. Measuring behind the MLP, during an Audyssey calibration, is a good example of that.

Not exactly how I had envisioned spending my 4th of July morning, but oh well!

Regards,
Mike
Mike,

For clarification first of all, it was NOT just that the measurements have a discernible difference, it is that I do not hear a discernible difference between Audyssey's 8 mic positions and your guide's 8 mic positions, with in front of the MLP versus behind the MLP. I understand not putting the microphone way behind the couch if I do not have seats back there because the couch could be blocking the speakers and the microphone could be picking up reflections from the back wall, which would cause Audyssey to correct something that it shouldn't. However, when we put the mic behind the couch, we put it right behind the MLP and raise it up so that the microphone is above the couch and about 6 inches from the MLP. The couch is not blocking the microphone and it is not so far back that it is going to be picking up the back wall reflections instead. What makes sense to me is that the calibration is getting an average around my head where I sit with Audyssey's 8 positions so that's why it goes behind where I sit. Even Dirac and ARC have positions behind the MLP, which again the couch is not interfering with because you put the microphone above ear level, which lines up over the couch/recliner. The only thing I have read in "the Guide" was that you said "Don't put the mic positions behind the couch and to put the positions in a circle including your head within that circle" without an explanation of why. Again, we have tried your recommended mic positions and Audysseys positions including right behind the MLP and did not HEAR a noticeable difference in sound quality. So I was wondering if there was more of a reason to keep the positions more in front of the MLP since again, Dirac and ARC use this method of calibrating.

Sorry for bothering you on your 4th of July. I want to make it clear that no one is forcing you to respond immediately to every post in this thread that you have made. Enjoy your 4th of July and please do not feel the need to respond immediately to my post. Thanks for your replies and sorry for any inconvenience this has caused you.
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post #2456 of 2484 Old 07-04-2020, 07:35 PM
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Originally Posted by mthomas47 View Post

The Audyssey omnidirectional microphone can pick-up both early and late reflections, of high-frequencies, in a way that will influence the room EQ that it performs. And yet, our brains would often have ignored some of those early and late reflections that Audyssey "heard", and which it tried to "correct". In those cases, an unnecessary correction can actually degrade the sound quality. The Audyssey microphone and our brains simply don't "hear" sounds in the same way. The better we understand that fact, the better we can help Audyssey (or other forms of room EQ) to help us to achieve improved sound quality.
Hi Mike,


+1 on the whole post, and just want to add this little info

Since, that our brain/head is not omnidirectional as a microphone. Since we have two ears, just as Dr. Floyd E. Toole found out in his many years of research in sound;
https://www.amazon.ca/Sound-Reproduc...r=8-1-fkmrnull
And is the reason, for a close pattern when doing a calibration.


Darth
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Originally Posted by mthomas47 View Post
We know from long experience with Audyssey, that Audyssey usually (another generalization) works best when we keep the microphone pattern fairly compact. Even Audyssey came to realize that over time, and now recommends a much smaller microphone spacing than they did 6-8 years ago. The reason for that is the fuzzy-logic weighting system that Audyssey uses to average the results of the measurements from multiple (usually 8) microphone positions. The more we prevent anomalous measurements of random peaks and valleys from skewing the average, the better room EQ we generally get.

So, we try to concentrate our measurements in the area of the most important listening position(s), knowing that we can't realistically EQ the entire room. From long observation of Audyssey results, I would say that the larger area we attempt to EQ, the more likely Audyssey is to degrade our sound quality at the MLP (main listening position) rather than to improve it. So, we try to keep our measurement mic at about ear height, because that is where we are actually listening, and we try to keep the measurement microphone fairly close to just one, or at the most two, listening positions.
My own personal experience corroborates this; the more positions used the more watered down the sound seemed to be, at least to my ears. After a period of time doing the requisite 8 locations I started experimenting and now I run 5 in a fairly tight grouping. But 5 is a bit misleading because I take the first and last measurement at the MLP, effectively giving that location double weighting. I'm not sure if it has a material impact on the algorithm, or the results achieved, but in my mind it should slant the EQ more toward the MLP than if I only tested that position once.
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post #2458 of 2484 Old 07-06-2020, 04:40 PM
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Silly-ass question or 3

Hi Folks,
Thanks to all of you for your contributions to the body of knowledge! Maybe you can provide some guidance. The classic dilemma, smooth bass in a small room: The room is 15.5 feet long, 11 feet wide, and 8 feet high. Thin carpet on concrete floor, doors on both side walls (not symmetrically located). The actual room modes are at: 35 Hz, 78 Hz, 105-110 Hz, and 140-150 Hz.

I cannot yet use REW successfully (it shows my bass response dropping by 20 dB below 55 Hz, which is absolutely not the case)...but I will learn what I'm doing wrong there, at another time.

I have been measuring at the MLP, 5.5 feet forward from the back wall. The front sub is a SVS PB13u, the back sub at present, is a SVS PB3000. Each sub is placed across the front (and back) wall, with the plane of the driver at mid-point across the width of the room, with the intent to control room modes. My first question is, should I move the subs so that each of them will have the driver directly facing the front and back wall, allowing a few inches of space? Due to a recent surgery, I can't try that for a week or two.

I am using a very flat signal generator into my Marantz SR7011, subs only. Reading with a Galaxy CM-140 calibrated by Herb Singleton, and applying corrections for the CM-140's response drops at lower frequencies. I am going to attempt to attach my measurement results, linear scale, after Audyssey (Flat).

Since there is a strong room mode at 105-110 Hz, I'm thinking of "starving" it by setting the AVR crossover at 110 or 115 Hz, and the subs' low-pass filter at maybe 100 or 105 Hz. Does this sound workable?

What about using PEQ, with PB13 at 31 Hz and PB3000 at 30 Hz, both with very narrow Q, hoping to not lose the response at 20 Hz along the way?

By the way, I have sad experience trying to match two different subs. I'd been using a PC12+ in the back, with the PC13u in front, and got surprisingly good agreement between them, except of course, the much lower max spl of the PC12+. I recently murdered the PC12+ amplifier, apparently by stupidly plugging and unplugging the signal connector with the sub running. Since I couldn't bring myself to spend the $ on a PB4000, I went for a great local deal on a nearly-new PB3000. I love the control features of its app, but it truly drops like a rock below 20 Hz. Oh well, lesson learned.

Bass is ok, but seems a little "muddy" to me. Thinking the bloat at 102 to 112 Hz might be the culprit...or should I be looking at the rise at 42 to 52 Hz? Thanks for any advice, and apologies for the long post and the linear, non-REW graph. Jack
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post #2459 of 2484 Old 07-07-2020, 08:58 AM - Thread Starter
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Originally Posted by bearr48 View Post
Hi Folks,
Thanks to all of you for your contributions to the body of knowledge! Maybe you can provide some guidance. The classic dilemma, smooth bass in a small room: The room is 15.5 feet long, 11 feet wide, and 8 feet high. Thin carpet on concrete floor, doors on both side walls (not symmetrically located). The actual room modes are at: 35 Hz, 78 Hz, 105-110 Hz, and 140-150 Hz.

I cannot yet use REW successfully (it shows my bass response dropping by 20 dB below 55 Hz, which is absolutely not the case)...but I will learn what I'm doing wrong there, at another time.

I have been measuring at the MLP, 5.5 feet forward from the back wall. The front sub is a SVS PB13u, the back sub at present, is a SVS PB3000. Each sub is placed across the front (and back) wall, with the plane of the driver at mid-point across the width of the room, with the intent to control room modes. My first question is, should I move the subs so that each of them will have the driver directly facing the front and back wall, allowing a few inches of space? Due to a recent surgery, I can't try that for a week or two.

I am using a very flat signal generator into my Marantz SR7011, subs only. Reading with a Galaxy CM-140 calibrated by Herb Singleton, and applying corrections for the CM-140's response drops at lower frequencies. I am going to attempt to attach my measurement results, linear scale, after Audyssey (Flat).

Since there is a strong room mode at 105-110 Hz, I'm thinking of "starving" it by setting the AVR crossover at 110 or 115 Hz, and the subs' low-pass filter at maybe 100 or 105 Hz. Does this sound workable?

What about using PEQ, with PB13 at 31 Hz and PB3000 at 30 Hz, both with very narrow Q, hoping to not lose the response at 20 Hz along the way?

By the way, I have sad experience trying to match two different subs. I'd been using a PC12+ in the back, with the PC13u in front, and got surprisingly good agreement between them, except of course, the much lower max spl of the PC12+. I recently murdered the PC12+ amplifier, apparently by stupidly plugging and unplugging the signal connector with the sub running. Since I couldn't bring myself to spend the $ on a PB4000, I went for a great local deal on a nearly-new PB3000. I love the control features of its app, but it truly drops like a rock below 20 Hz. Oh well, lesson learned.

Bass is ok, but seems a little "muddy" to me. Thinking the bloat at 102 to 112 Hz might be the culprit...or should I be looking at the rise at 42 to 52 Hz? Thanks for any advice, and apologies for the long post and the linear, non-REW graph. Jack

Hi Jack,

I'm really not sure how much I can help, but I will make a few comments. Trying to give someone else advice, in a situation like this, is a little bit like a physician trying to diagnose a serious illness from a description of symptoms in an email. Good audio requires trial-and-error within a specific listening space. Sometimes, we can make some generalizations about things, but until you try them for yourself, no one else can know what will actually work and what won't. (The medical analogy I used would require X-rays, lab tests, physical examination, etc.) In both cases, the diagnosis and treatment would be specific to the individual circumstance.

Here are some general ideas to consider. First, you may be getting some phase-cancellation due to the different tuning points of the two subs. The PB13 can be tuned to either 20Hz (Standard mode) or 16Hz (Extended mode). The PB3000 has a single 18Hz tuning mode. I might try the PB13 in Standard (20Hz) mode, and see if that helps at all.

Second, I see no reason to point the subs toward the walls, but you could try some other room locations. Since you are not sitting at about the mid-point of the room, you might try both subs on the front wall, or in diagonal corners (front left and rear right, or vice-versa) for instance.

Third, after Audyssey runs, you could try adjusting the phase on one of the subs to see if that helps. Do that after trying the first two options, if you have the patience and the physical ability to move the subs around in the room. (Use floor sliders under the subs.) Subwoofer location suggestions are necessarily theoretical. The only real way to know where the subs will work best is to test alternative locations.

Fourth, even if the subs cancel each other a bit at 100-120Hz, it may not matter if your speakers are crossed at about 80Hz or so. And, you may not have cancellation between the speakers and the subs. If you don't, your speakers will fill-in for the subs at those frequencies, and the subs will be rolling-off anyway. You can certainly try using a HPF of about 100Hz on the subs if you want to. Cascading crossovers, described in Section III-C of the actual Guide linked below, is often implemented with an 80Hz HPF for the subs.

Fifth, the muddiness you describe could be attributable to DEQ, if you are using that feature. You could experiment with that on and off, even before you begin to move your subs around (if you choose to try that). If you move the subs, or change from Extended to Standard mode for the PB13, you should run Audyssey again. As you probably already know, the "Flat" setting has no effect on bass frequencies. You can read the Guide for more information on that.

As you can tell from the nature of my advice, this is really a trial-and-error exercise that only you can perform. It can be a little bit of trouble to get the sound in our rooms where we want it to be. The good news is that we all get to choose how much trouble we are willing to go to, and when we are willing to say that we are satisfied. The other good news is that there is no hurry. Some of us may spend years getting the sound in our rooms just the way we want it. And, there doesn't have to be any particular feeling of urgency about it, because we continue to learn as we go.

I hope this response helps a little!

Regards,
Mike

GUIDE TO SUBWOOFER CALIBRATION AND BASS PREFERENCES

* The Guide linked above is a comprehensive guide to Audio & HT systems, including:
Speaker placements & Room treatments; HT calibration & Room EQ; Room gain; Bass
Preferences; Subwoofer Buyer's Guide: Sealed/ported; ID subs; Subwoofer placement.

Last edited by mthomas47; 07-07-2020 at 10:35 AM. Reason: Typo
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post #2460 of 2484 Old 07-07-2020, 01:13 PM
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I would like to give another HUGE shootout to @mthomas47 for such an informative thread. My fiance and I have both read it now and both agree that this thread sets the bar for a complete guide to better understanding the basics and complexities of home theater. We also appreciate that Mike and others take the time to respond to help everyone, whether new, intermediate or advanced in home theater. We cannot thank him enough for setting the bar so high in these regards. This is the type of "service" and comprehensive work we like to see in a community where there is such a wide range of different versed users. Mike even took time out of his day on the 4th of July to respond to my question that wasn't fully answered in the comprehensive guide. We are beginning to see there are not a lot of people in this community like Mike and others who have helped us in this thread. We quickly found that when we upgraded our one theater room to Dirac recently. I hope this thread continues to get more users involved because it is truly a hidden gem in my opinion. It has helped us out EXCEPTIONALLY on our home theater journey in the last few years. Again, thank you Mike and all who contribute to this thread because without you guys, we would not thoroughly understand the countless aspects involved with having a home theater system.

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