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post #4591 of 4663 Old 08-17-2016, 07:41 PM - Thread Starter
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Originally Posted by coolrda View Post
We've already proved that's impossible in a room. You can hit all three metrics, but it won't be balanced.
As I mentioned above, this is Mk's setup...

Granted....this is probably not practical for most, but his setup proves that it is possible, correct?


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Another fallacy is this idea that Crowsons and other TT's somehow aren't real compared to a subwoofer wrt TR. Either that person doesn't know what their talking about, hasn't experienced it or has on a system that's not properly setup or simply it's in their head. I was this person.
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It's around 13-14hz where my subs stop producing strong useful TR from a subjective feel.
I've experienced crowsons...and they are awesome for sure. Very realistic! However, there's a difference in overall 'feel' between a nearfield sub and an TT. They are different. @SBuger and @carp can chime in as I know they run crowsons and nearfields subs.

I'd say the lower you go in frequency, the more difficult is for you to tell a difference. But IME, 15hz and up nearfield does in fact feel different compared to no nearfield subs and a crowson.
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post #4592 of 4663 Old 08-17-2016, 09:46 PM
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Originally Posted by dominguez1 View Post
As I mentioned above, this is Mk's setup...

Granted....this is probably not practical for most, but his setup proves that it is possible, correct?




I've experienced crowsons...and they are awesome for sure. Very realistic! However, there's a difference in overall 'feel' between a nearfield sub and an TT. They are different. @SBuger and @carp can chime in as I know they run crowsons and nearfields subs.

I'd say the lower you go in frequency, the more difficult is for you to tell a difference. But IME, 15hz and up nearfield does in fact feel different compared to no nearfield subs and a crowson.

What!? No that's not correct. Your saying he changed room gain ratio with a port? He has stated that he had a 14.5db gain and a corresponding gain in TR and PR that the wife complains about. He never got around to rerunning EOT/VS. I've carefully looked over his data and there's no doubt there's gains, equal gains to each component. His SPL went up his TR and his PR. The room still has the same ratios. Ports don't change physics.

Let me put it to you this way. In my room, you wouldn't be able to tell the difference. And actually you notice the Crowsons more as frequency drops because of the TR gains, not less. But I admit, it took a some of work to get them there. You haven't experienced the Cool Crowson Experience. It a night and day difference. It's the same with your MBM. I use those a couple times a year. I love them. But I wouldn't think of posting my thoughts until it's been in my system, thoroughly measured and tweaked for a month. I've jumped to too many conclusion doing that over the years.

The pressure you felt in MK's room when you visited is the same you'd experience in mine. There almost carbon copies. That's what 1400cuft rooms do best. Blackout pressure with very little effort for sure. I had tinnitus. I don't want to go through that again. I can imagine how devastating his room is now. Yikes.

Putting all of the above aside this is the point I'm trying to make. Using my room for this example. I have 4x15's and 8x18's(the vertical stack dual opposed 4x18's, then 4x18's in individual cabs and the 4x15's in the two front cabs under the screen). I use and have thoroughly measured three basic setups. 4x15(front)+8x18(rear), 4x18(front)+4x18(rear) and currently 4x15(front)+4x18(rear). The current setup has the best midbass and don't need the 8x18 nearfield with the MA's. All three setups have netted a 134db peak. Pressure feels the same. Using your SPL+TR/2 equation I have 3 very different PR scores. And yet, if you stood in my room blindfolded, you wouldn't be able to tell/feel a difference pressure wise. Actually I think your original scorecard gives us a better metric with using the SPL to cu ft. I think my room was a 175 counting the 8x18's. That's closer than anything I see on the new one. The other thing is you can stop at 5. You have to use their true peak SPL otherwise we all will measure the same. If we all get 5+5 were back to square one. Trust the objective data. You'll see just how precise it can be. In MK's case and the rest of us. Ok I'm done with point/counterpoint. You do it the way you see fit and I'll post my score using what you decide on.
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post #4593 of 4663 Old 08-18-2016, 12:37 AM
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Quote:
Originally Posted by dominguez1 View Post

I've experienced crowsons...and they are awesome for sure. Very realistic! However, there's a difference in overall 'feel' between a nearfield sub and an TT. They are different. @SBuger and @carp can chime in as I know they run crowsons and nearfields subs.

I'd say the lower you go in frequency, the more difficult is for you to tell a difference. But IME, 15hz and up nearfield does in fact feel different compared to no nearfield subs and a crowson.
Its way to late now, so I'll try to give a decent response tomorrow.

My Home Theater Set Up ....... FS: Rythmik FV15HP.......
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post #4594 of 4663 Old 08-18-2016, 06:58 AM
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Here's an example Dom. I make you a cup of coffee everyday. Same coffee, 9 parts coffee 1 part cream. You used to the same thing day after day. One day i make it 5 to 5. One sip your gonna have one of those Home Alone shocking looks. What happen to my coffee, right? But if I change that ratio fractions of a part daily, in a month your drinking 50/50 coffee, and loving it, non the wiser.

Same with building a huge system in a small tight room. The pressure is shocking, startling, the best thing ever. But once you experience outdoor GP balanced response inside a room, over a period of months to offset the decades of imbalance, its easily dismissed or lost.
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post #4595 of 4663 Old 08-18-2016, 07:42 AM
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I agree about the balance, I had 5 star Pressure and Spl along with extension to 3-4hz. I has TR but once I ported it balanced the TR with the rest. I never lost any of the others though. I used to use shakers but I took them out but I still had the pressure with them, not like having 20hz subs with shakers which I feel will miss the low end Spl which is pressure. I believe once you have high Spl you have pressure, the difference is how low it goes which comes to extension. I would think knowing someone's system has high Spl down low means high pressure or higher pressure than someone who has less extension. I mean SPL is pressure, no? The difference is extension. When you get extension from ports and room it increases TR compared to a system that gets extension from room gain alone. My shakers shook much more like the ported system for sure and not careful even more but out of balanced.
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post #4596 of 4663 Old 08-18-2016, 10:09 AM
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Quote:
Originally Posted by dominguez1 View Post
If not PR, than what is it?
well it's TR with an assumption that the source of the TR is PR but PR is just one possible source (another might be transmission through the floor/structure of the room for example) and there's no standard way in which PR will induce TR in a particular seat. It might require a ludicrous amount to do that in one room/seat but not so much in another. It also seems to suggest the point of PR is to induce TR but that's not the impression I get.

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Do we agree that there is a difference here between a systems that rolls off at 20hz but uses transducers for reference TR vs a system that doesn't use transducers, but still has reference TR?
sure

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Example 1 is @MKtheater . He's got reference TR down to at least 10hz, and likely 5hz given the tune. What is overkill about his setup? He listens at reference volumes, nothing crazy, but his ported IB provides all the TR he needs at reasonable volumes I believe...
a ported IB can fairly be considered a pretty extreme setup, whether it's overkill or not depends on your point of view & requirements but it's definitely an aggressively powerful system
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post #4597 of 4663 Old 08-18-2016, 12:57 PM
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Originally Posted by MKtheater View Post
I agree about the balance, I had 5 star Pressure and Spl along with extension to 3-4hz. I has TR but once I ported it balanced the TR with the rest. I never lost any of the others though. I used to use shakers but I took them out but I still had the pressure with them, not like having 20hz subs with shakers which I feel will miss the low end Spl which is pressure. I believe once you have high Spl you have pressure, the difference is how low it goes which comes to extension. I would think knowing someone's system has high Spl down low means high pressure or higher pressure than someone who has less extension. I mean SPL is pressure, no? The difference is extension. When you get extension from ports and room it increases TR compared to a system that gets extension from room gain alone. My shakers shook much more like the ported system for sure and not careful even more but out of balanced.
Well said. Now that it's balanced, I really enjoy the experience and listen and demo at lower levels. I noticed its much easier to differentiate between ST's with strong ULF and ones that are filtered.
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post #4598 of 4663 Old 08-18-2016, 02:03 PM
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I agree, I can watch movies all day at reference and flat BUT my low end is hot naturally. When I say low end I mean ULF. If you are familiar with the Inuke gain knobs I have all my gains at 12 up straight up. If I turn the gain one click to the right the bass gets very strong and if I turn it two clicks it is crazy with my projector shaking so much. I am not sure what the dB differences are on the Inuke gains but I am thinking 3 dB per click Or less?
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post #4599 of 4663 Old 08-18-2016, 02:04 PM
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Sorry guys, I am typing on my phone and it writes like English is my second language LOL!
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post #4600 of 4663 Old 08-18-2016, 05:04 PM
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In my room I'm good down to around 12-13 Hz. Nearfield sub without the transducer is different than using less spl and with the TT's and nearfield subs. Is one better, I can't say that. I watch some movies +/- transducers and find it equally enjoyable.

Now, running things hot means more spl and pressure. I don't find this more enjoyable. I thinks there is a point that enough of each component leads to a balance and enjoyable experience. To much of any one can ruin the expeience. Now, what all of us like will vary from pereson to person and room to room.

I have a large room but, I routinely watch movies with some doors open to keep down the weighted feeling. Even to much bopping on the back and seat bottom can become a distraction. This point with PR and TR is subjective because what one person considers enough may be to much or not enough for another person.

I will say that I'm in a very comfortable place because I can easily tailor the TR/PR/ and spl max quickly. The TT's are nice to have because you can so quickly and easily adjust the TR. Most of us have enough spl and are looking for the TR +/- the PR.
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post #4601 of 4663 Old 08-18-2016, 06:31 PM - Thread Starter
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Quote:
Originally Posted by coolrda View Post
What!? No that's not correct. Your saying he changed room gain ratio with a port? He has stated that he had a 14.5db gain and a corresponding gain in TR and PR that the wife complains about. He never got around to rerunning EOT/VS. I've carefully looked over his data and there's no doubt there's gains, equal gains to each component. His SPL went up his TR and his PR. The room still has the same ratios. Ports don't change physics.
No. Look back, his SPL actually was lower with the ported, but his TR stayed the same. I never understood the room gain ratio you're referring to, so won't try and speak in those terms. What we do know is that SPL can remain the same and produce different TR results keeping everything else equal. This has been proven many times, and I think you agreed to it.

Regardless, MK's setup can reach Reference TR while not needing to go crazy above reference SPL levels like you needed to do in your room. His ported IB provides that extra TR and lower levels of SPL compared to sealed. MK's has confirmed this multiple times.

MK's setup IS an example of achieving Reference TR without transducers, so it is possible was my point.

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Putting all of the above aside this is the point I'm trying to make. Using my room for this example. I have 4x15's and 8x18's(the vertical stack dual opposed 4x18's, then 4x18's in individual cabs and the 4x15's in the two front cabs under the screen). I use and have thoroughly measured three basic setups. 4x15(front)+8x18(rear), 4x18(front)+4x18(rear) and currently 4x15(front)+4x18(rear). The current setup has the best midbass and don't need the 8x18 nearfield with the MA's. All three setups have netted a 134db peak. Pressure feels the same. Using your SPL+TR/2 equation I have 3 very different PR scores. And yet, if you stood in my room blindfolded, you wouldn't be able to tell/feel a difference pressure wise. Actually I think your original scorecard gives us a better metric with using the SPL to cu ft. I think my room was a 175 counting the 8x18's. That's closer than anything I see on the new one. The other thing is you can stop at 5. You have to use their true peak SPL otherwise we all will measure the same. If we all get 5+5 were back to square one. Trust the objective data. You'll see just how precise it can be. In MK's case and the rest of us. Ok I'm done with point/counterpoint. You do it the way you see fit and I'll post my score using what you decide on.
Trust me, I'm listening to you guys on PR. Just trying to get the scorecard (while we're revising it) as accurate as possible (that could include or omit the PR score).
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post #4602 of 4663 Old 08-18-2016, 06:55 PM - Thread Starter
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Originally Posted by coolrda View Post
Here's an example Dom. I make you a cup of coffee everyday. Same coffee, 9 parts coffee 1 part cream. You used to the same thing day after day. One day i make it 5 to 5. One sip your gonna have one of those Home Alone shocking looks. What happen to my coffee, right? But if I change that ratio fractions of a part daily, in a month your drinking 50/50 coffee, and loving it, non the wiser.

Same with building a huge system in a small tight room. The pressure is shocking, startling, the best thing ever. But once you experience outdoor GP balanced response inside a room, over a period of months to offset the decades of imbalance, its easily dismissed or lost.
I get it...don't argue the point about balance at all. I agree.

Let's not forget though that PR is more than just pressure (weight, ear popping)...when you have a nearfield sub right at your back, the same waves that are vibrating your seating are also impacting your body (at your back, seat, etc.).

This is also PR.

Transducers will NEVER reproduce the effect of soundwaves impacting your back, etc.. This is also one of the differences between nearfield and transducers. Can we represent this in a score? I'm hearing you guys...probably not. However, let's not jump to the conclusion that transducers can recreate nearfield...this is simple physics, and it certainly cannot. It might be very close so that it is perceived that way, but they are scientifically different.
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post #4603 of 4663 Old 08-18-2016, 07:03 PM - Thread Starter
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Originally Posted by derrickdj1 View Post
In my room I'm good down to around 12-13 Hz. Nearfield sub without the transducer is different than using less spl and with the TT's and nearfield subs. Is one better, I can't say that. I watch some movies +/- transducers and find it equally enjoyable.

Now, running things hot means more spl and pressure. I don't find this more enjoyable. I thinks there is a point that enough of each component leads to a balance and enjoyable experience. To much of any one can ruin the expeience. Now, what all of us like will vary from pereson to person and room to room.

I have a large room but, I routinely watch movies with some doors open to keep down the weighted feeling. Even to much bopping on the back and seat bottom can become a distraction. This point with PR and TR is subjective because what one person considers enough may be to much or not enough for another person.

I will say that I'm in a very comfortable place because I can easily tailor the TR/PR/ and spl max quickly. The TT's are nice to have because you can so quickly and easily adjust the TR. Most of us have enough spl and are looking for the TR +/- the PR.
Yes...having TT's it is MUCH MUCH easier to dial in your TR. That's for sure. And most folks don't have the option to build a ported IB and TTs are a great way to get that reference TR! No argument there as well!

My point is that in a perfect world, you wouldn't need TTs, and you could do it just with subs at reasonable SPL levels. This to me is the ultimate experience...it has all with balance. Is it realistic for most? Definitely not! But, doesn't mean that it shouldn't be a goal if you can design it that way.
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post #4604 of 4663 Old 08-18-2016, 07:05 PM - Thread Starter
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Also, I've owned TTs (Clark's), and they didn't come close to recreating the nearfield sub experience.

The difference? PR.
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post #4605 of 4663 Old 08-18-2016, 07:46 PM - Thread Starter
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Originally Posted by coolrda View Post

Putting all of the above aside this is the point I'm trying to make. Using my room for this example. I have 4x15's and 8x18's(the vertical stack dual opposed 4x18's, then 4x18's in individual cabs and the 4x15's in the two front cabs under the screen). I use and have thoroughly measured three basic setups. 4x15(front)+8x18(rear), 4x18(front)+4x18(rear) and currently 4x15(front)+4x18(rear). The current setup has the best midbass and don't need the 8x18 nearfield with the MA's. All three setups have netted a 134db peak. Pressure feels the same. Using your SPL+TR/2 equation I have 3 very different PR scores. And yet, if you stood in my room blindfolded, you wouldn't be able to tell/feel a difference pressure wise.
Was TR different in each of those config? Which was the most/least? Was that without the MA?
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post #4606 of 4663 Old 08-18-2016, 08:02 PM
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Yes...having TT's it is MUCH MUCH easier to dial in your TR. That's for sure. And most folks don't have the option to build a ported IB and TTs are a great way to get that reference TR! No argument there as well!

My point is that in a perfect world, you wouldn't need TTs, and you could do it just with subs at reasonable SPL levels. This to me is the ultimate experience...it has all with balance. Is it realistic for most? Definitely not! But, doesn't mean that it shouldn't be a goal if you can design it that way.
Yep. Don't need them outdoor GP. But, if you think we have a problem with global warming now, wait to @BassThatHz relocates his system outdoors. Oops, did I say outdoor theater? I meant underground anechoic.
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post #4607 of 4663 Old 08-18-2016, 09:18 PM
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Was TR different in each of those config? Which was the most/least? Was that without the MA?
Yes TR was very different. The most TR was the 8x18's near field with 4 right behind the seat. I like this the least. The least TR was the 4x15's up front and the 4x18's VDO. I like this the most. The 8x18's, 4 fronts and rear were a step down. I actually prefer the HF15's above 20hz, they just don't have the displacement. I like the 18's below 20hz for obvious reasons. I didn't really feel much was gained with the 12 subs over any of the 8 sub combos. There could have been response nulls or other issues introduce because of the spread, I don't know. I just prefer the 4x15, 4x18VDO setup the best. Thats what I'm using currently. Though I don't have the TR I had with the other, the PR and midbass are magnificent. This was all a year prior to the MA's.
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post #4608 of 4663 Old 08-18-2016, 10:45 PM
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Originally Posted by dominguez1 View Post

I've experienced crowsons...and they are awesome for sure. Very realistic! However, there's a difference in overall 'feel' between a nearfield sub and an TT. They are different. @SBuger and @carp can chime in as I know they run crowsons and nearfields subs.

I'd say the lower you go in frequency, the more difficult is for you to tell a difference. But IME, 15hz and up nearfield does in fact feel different compared to no nearfield subs and a crowson.
First I should say that my room is very different than most of you guys here with small dedicated sealed rooms. I'm in a very large open floorplan house with my HT setup in the living room. I don't get a ton of that ear popping pressure/weight that you guys are talking about. I'm ok with that though as I think it probably allows me to run my subs a little hotter and intense when I have the desire to do so and not have it be so hard on my ears. I kind of have a bit of trouble with my ears with real high pressure/weight. I still get some of it though, at least in various parts of the house (if I don't leave the pantry door open that thing goes crazy on the ULF stuff). Now I do get the kind of PR that Dom was also talking about from the nearfeilds subs sending pressure waves into your seat and impacting your body. So from the get go, my system is probably not as balanced as some of you guys from and overall standpoint - PR(weight, ear popping), PR (sound waves heating your back), TR, SPL, great FR into single digits, etc. ratio. But we all have to do the best we can with the rooms we are in. For the most part, I'm extremely happy with it all. I am a bit envious of you guys with the dedicated room though

I love my Crowsons, BK LFE's and my nearfeild subs right behind me. IME they all contribute just a bit differently and I love them all for different reasons. For the most part if I keep them all within reasonable levels of each other, they pretty much blend seamlessly as a whole and most of the time I'm not really able to tell which is coming from which. Occasionally for fun I'll play the game of seeing if I can tell which is which - TT' or Subs, and I don't always get it right LOL. I'll watch a scene with both, then mute the sub and let the TT's only do there thing, and vise versa and mute the TT's and let the subs run. It surprises me sometimes just how realistic feeling the TT's can be if they are integrated well. But as with anything, it can be overdone if not careful.

I will say that I prefer the TT's in combination with the nearfields opposed to no nearfeilds and TT's. Levels etc are not quite as critical and more forgiving, allowing them to blend in easier IME.

I'll also say that when listening at really high SPL levels, my nearfields usually start to dominate over the TT's, which is fine by me since it's probably the most realistic of all. I do a fair amount of moving watching at about -12 to -15 MV and in my system around this volume the two blend to together very well and the TT's really add to the experience, even with triple nearfield 18's at my back. Although I do crank my system up a lot, I don't always want to listen at ear blistering levels in my untreated living room.

I think the Crowsons are the most realistic of the two. But I like the BK's as well ( I run them both on the same couch) because they kind of add a little something that my subs alone and Crowsons don't do quite as well on my concrete slab and style of my couch. I like to think of as the trampoline effect. My couch is a little different form the actual theater chairs that most of you guys are using. Its a three seat leather couch that has a metal rectangular frame on the bottom. I specifically bolted two BK LFE's in the middle, right under the MLP because it has a lot of flex and when they are cranked up, it makes me feel like I'm on a trampoline. Some may not like this and say its unrealistic/unnatural, but I love it and feel that it works well with what the Crowsons and nearfields add. I find that this effect is the strongest in the ~ 15 to 27ish hz range (where the BK's shine IMO, at least on my couch) and can be almost vision blurring when cranked up. Again, probably not the most natural and some may hate it, but I love it and find it works well, especially with the nearfields delivering the slam.

And then there are the Crowsons! Man I love these things as well. They are so realistic and can add a little that the nearfeilds alone sometimes don't IMO, like certain vibrations in the armrests, under 10hz stuff, etc (at least at moderate volumes with my set up and couch). My Crowson set up is probably not quite as optimal as coolrda's because of the style of my couch and only 2 vs his 4, but I still love them and will probably add 2 more eventually to help distribute the TR a little more evenly to each seat. I think that the Crowson experience would be the most optimum the way he has them set up on actual theater chairs with one on each back leg of each seat. I'm betting his Crowson setup really is killer! So I can definitely understand why he values them so much. They are awesome and I wouldn't want to be without them.

And last but definitely not least, the Nearfields! IMO they are awesome and I most definitely would not want to be without these! They can deliver serious Slam, TR, and PR all at the same time. I would choose them over the TT's if I had to make a choice. Luckily I don't have to choose and can use both!
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post #4609 of 4663 Old 08-18-2016, 10:46 PM
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I get it...don't argue the point about balance at all. I agree.

Let's not forget though that PR is more than just pressure (weight, ear popping)...when you have a nearfield sub right at your back, the same waves that are vibrating your seating are also impacting your body (at your back, seat, etc.).

This is also PR.

Transducers will NEVER reproduce the effect of soundwaves impacting your back, etc.. This is also one of the differences between nearfield and transducers. Can we represent this in a score? I'm hearing you guys...probably not. However, let's not jump to the conclusion that transducers can recreate nearfield...this is simple physics, and it certainly cannot. It might be very close so that it is perceived that way, but they are scientifically different.
And a subwoofer will never be able to reproduce tactile effects like an actuator. Mine have a only a 1/4" throw and pulls above a 1e-01. There's actuator that shake a 100 story building. They are two different components. That do two different things. Thats why I have both. While subs have a TR though acoustic coupling, its far less efficient. Thats why we strap them to the back of the seat. Having experimented with all kinds of arrays and combinations, screen wall provides the best tactile quality. Thats why I have four eighteens sitting here doing nothing. The nearfield dominate because of the intensity. But, stand back at the full wave distance from a sub and the tactile presence is incredible. Its better quality but quantity dominates in the HT environment. My philosophy has always been get the sub as far away from you as possible, using whatever means is necessary. Let the wave form.

When I started the latest room, with the exception of symmetry, I was open to anything with the purpose of Suspension of Disbelief. When you hear about the fellas here with suspended floors and the ripple effect it has like my Dad's 25 year old crappy 10" subs rumbling his suspended floor, well thats what I wanted. That effect is the Suspension of Disbelief. I have all of what you mentioned and described above with the exception of TR amplitude. After adding the MA's to the 12 subs, TR went through the roof. While it was unnatural at first it was because the balance changed, nothing else. I had way more TR at all frequencies with below 15hz being in the double digits and 24db TR increase at 6hz! When I removed the 4 18's nothing changed. In fact mid bass improved. Overall bass quality improved as did subtle detail including tactile details as things were less localizable and directional with sub against backrest. I want my theater to feel like a lightening strikes inside or and earthquake is real and not a sub shaking my chair simulating an earthquake. What I have now is superior to the sub hitting my seat. I would not have spent the cash if it didn't. I have great tactile resolution and clean distortion-free and dynamic PR.
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post #4610 of 4663 Old 08-19-2016, 06:54 AM
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First I should say that my room is very different than most of you guys here with small dedicated sealed rooms. I'm in a very large open floorplan house with my HT setup in the living room. I don't get a ton of that ear popping pressure/weight that you guys are talking about. I'm ok with that though as I think it probably allows me to run my subs a little hotter and intense when I have the desire to do so and not have it be so hard on my ears. I kind of have a bit of trouble with my ears with real high pressure/weight. I still get some of it though, at least in various parts of the house (if I don't leave the pantry door open that thing goes crazy on the ULF stuff). Now I do get the kind of PR that Dom was also talking about from the nearfeilds subs sending pressure waves into your seat and impacting your body. So from the get go, my system is probably not as balanced as some of you guys from and overall standpoint - PR(weight, ear popping), PR (sound waves heating your back), TR, SPL, great FR into single digits, etc. ratio. But we all have to do the best we can with the rooms we are in. For the most part, I'm extremely happy with it all. I am a bit envious of you guys with the dedicated room though

I love my Crowsons, BK LFE's and my nearfeild subs right behind me. IME they all contribute just a bit differently and I love them all for different reasons. For the most part if I keep them all within reasonable levels of each other, they pretty much blend seamlessly as a whole and most of the time I'm not really able to tell which is coming from which. Occasionally for fun I'll play the game of seeing if I can tell which is which - TT' or Subs, and I don't always get it right LOL. I'll watch a scene with both, then mute the sub and let the TT's only do there thing, and vise versa and mute the TT's and let the subs run. It surprises me sometimes just how realistic feeling the TT's can be if they are integrated well. But as with anything, it can be overdone if not careful.

I will say that I prefer the TT's in combination with the nearfields opposed to no nearfeilds and TT's. Levels etc are not quite as critical and more forgiving, allowing them to blend in easier IME.

I'll also say that when listening at really high SPL levels, my nearfields usually start to dominate over the TT's, which is fine by me since it's probably the most realistic of all. I do a fair amount of moving watching at about -12 to -15 MV and in my system around this volume the two blend to together very well and the TT's really add to the experience, even with triple nearfield 18's at my back. Although I do crank my system up a lot, I don't always want to listen at ear blistering levels in my untreated living room.

I think the Crowsons are the most realistic of the two. But I like the BK's as well ( I run them both on the same couch) because they kind of add a little something that my subs alone and Crowsons don't do quite as well on my concrete slab and style of my couch. I like to think of as the trampoline effect. My couch is a little different form the actual theater chairs that most of you guys are using. Its a three seat leather couch that has a metal rectangular frame on the bottom. I specifically bolted two BK LFE's in the middle, right under the MLP because it has a lot of flex and when they are cranked up, it makes me feel like I'm on a trampoline. Some may not like this and say its unrealistic/unnatural, but I love it and feel that it works well with what the Crowsons and nearfields add. I find that this effect is the strongest in the ~ 15 to 27ish hz range (where the BK's shine IMO, at least on my couch) and can be almost vision blurring when cranked up. Again, probably not the most natural and some may hate it, but I love it and find it works well, especially with the nearfields delivering the slam.

And then there are the Crowsons! Man I love these things as well. They are so realistic and can add a little that the nearfeilds alone sometimes don't IMO, like certain vibrations in the armrests, under 10hz stuff, etc (at least at moderate volumes with my set up and couch). My Crowson set up is probably not quite as optimal as coolrda's because of the style of my couch and only 2 vs his 4, but I still love them and will probably add 2 more eventually to help distribute the TR a little more evenly to each seat. I think that the Crowson experience would be the most optimum the way he has them set up on actual theater chairs with one on each back leg of each seat. I'm betting his Crowson setup really is killer! So I can definitely understand why he values them so much. They are awesome and I wouldn't want to be without them.

And last but definitely not least, the Nearfields! IMO they are awesome and I most definitely would not want to be without these! They can deliver serious Slam, TR, and PR all at the same time. I would choose them over the TT's if I had to make a choice. Luckily I don't have to choose and can use both!
Excellent description of your experience. Rooms make a huge difference to the various responses and recent measurement I've taken suggest that seating is the same or more so. So now you have two components that make no sound but have a huge impact to overall responses and can make a night and day difference. My seating has a huge 8-12hz peak over the MA alone. Different seating can have different TR's. Very interesting.
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post #4611 of 4663 Old 08-19-2016, 12:46 PM
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The TT's work in synergy with the subs. Increasing spl to get more TR with nearfield sub in my room will lead to dulling of the explosions. There's just to much going on that close and keep the spl within a reasonalble range just helps keep things nice and crisp. I have experience this in other HT.

Yes, there is a great PR and TR but the crispness of the system is duller. Sometimes getting a nice balance is hard to do in the HT. With TT's the job is a bit easier. I will not give up my TT's which seem to match the ported system very well. With a good balance I'm like Goldilocks and the porridge is just right.

Side note: I'm having Omnimic problems as are other people. There is a glitch with the software working in windows 10. Parts Express is contacting the developer to see what can be done. I may be coverting to REW as a backup for now but, need to give them some time to find a solution.
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post #4612 of 4663 Old 08-19-2016, 10:46 PM
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Yep. I have a very clean and highly resolved dynamic now with very low distortion. Explain what the glitch is.
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post #4613 of 4663 Old 08-20-2016, 07:00 AM
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I have recently started reading through the whole thread, but I have a long way to go. Great stuff, with lot's of interesting side discussions!

Would someone please take a stab at estimating the 10Hz response of a PB13 Ultra in 15Hz mode? Data-Bass lists the 12.5Hz response at 89.3. The SB drops about 5.5db from 12.5Hz to 10Hz, so I assume it would have to be a little more than that. Data-Bass isn't showing any 10Hz numbers for any other subs, below the SB's 83Hz, so whether there is just too much distortion below that point, or some other reason for not showing anything lower, I don't know.

Would an 11db drop be plausible considering the slope difference between sealed and ported? I have a tangential room mode at 10Hz, and am trying to guesstimate what, if anything, it might be able to boost. Thanks for any help.

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post #4614 of 4663 Old 08-20-2016, 07:35 AM
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Originally Posted by mthomas47 View Post
I have recently started reading through the whole thread, but I have a long way to go. Great stuff, with lot's of interesting side discussions!

Would someone please take a stab at estimating the 10Hz response of a PB13 Ultra in 15Hz mode? Data-Bass lists the 12.5Hz response at 89.3. The SB drops about 5.5db from 12.5Hz to 10Hz, so I assume it would have to be a little more than that. Data-Bass isn't showing any 10Hz numbers for any other subs, below the SB's 83Hz, so whether there is just too much distortion below that point, or some other reason for not showing anything lower, I don't know.

Would an 11db drop be plausible considering the slope difference between sealed and ported? I have a tangential room mode at 10Hz, and am trying to guesstimate what, if anything, it might be able to boost. Thanks for any help.

Regards,
Mike
With the burst test, data-bass shows "Could Not Produce Passing Result" at 10 Hz (Look at the Static Graphs tab). You can look at the Maximum Long Term Output results to see that the PB13 Ultra in 15Hz mode drops about 12 dB from 12.5 Hz to 10 Hz.
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post #4615 of 4663 Old 08-20-2016, 07:52 AM
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With the burst test, data-bass shows "Could Not Produce Passing Result" at 10 Hz (Look at the Static Graphs tab). You can look at the Maximum Long Term Output results to see that the PB13 Ultra in 15Hz mode drops about 12 dB from 12.5 Hz to 10 Hz.
Thank you very much! I must have missed that. My guess of about 11db was in the ballpark.
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post #4616 of 4663 Old 08-20-2016, 12:45 PM
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First I should say that my room is very different than most of you guys here with small dedicated sealed rooms. I'm in a very large open floorplan house with my HT setup in the living room. I don't get a ton of that ear popping pressure/weight that you guys are talking about. I'm ok with that though as I think it probably allows me to run my subs a little hotter and intense when I have the desire to do so and not have it be so hard on my ears. I kind of have a bit of trouble with my ears with real high pressure/weight. I still get some of it though, at least in various parts of the house (if I don't leave the pantry door open that thing goes crazy on the ULF stuff). Now I do get the kind of PR that Dom was also talking about from the nearfeilds subs sending pressure waves into your seat and impacting your body. So from the get go, my system is probably not as balanced as some of you guys from and overall standpoint - PR(weight, ear popping), PR (sound waves heating your back), TR, SPL, great FR into single digits, etc. ratio. But we all have to do the best we can with the rooms we are in. For the most part, I'm extremely happy with it all. I am a bit envious of you guys with the dedicated room though

I love my Crowsons, BK LFE's and my nearfeild subs right behind me. IME they all contribute just a bit differently and I love them all for different reasons. For the most part if I keep them all within reasonable levels of each other, they pretty much blend seamlessly as a whole and most of the time I'm not really able to tell which is coming from which. Occasionally for fun I'll play the game of seeing if I can tell which is which - TT' or Subs, and I don't always get it right LOL. I'll watch a scene with both, then mute the sub and let the TT's only do there thing, and vise versa and mute the TT's and let the subs run. It surprises me sometimes just how realistic feeling the TT's can be if they are integrated well. But as with anything, it can be overdone if not careful.

I will say that I prefer the TT's in combination with the nearfields opposed to no nearfeilds and TT's. Levels etc are not quite as critical and more forgiving, allowing them to blend in easier IME.

I'll also say that when listening at really high SPL levels, my nearfields usually start to dominate over the TT's, which is fine by me since it's probably the most realistic of all. I do a fair amount of moving watching at about -12 to -15 MV and in my system around this volume the two blend to together very well and the TT's really add to the experience, even with triple nearfield 18's at my back. Although I do crank my system up a lot, I don't always want to listen at ear blistering levels in my untreated living room.

I think the Crowsons are the most realistic of the two. But I like the BK's as well ( I run them both on the same couch) because they kind of add a little something that my subs alone and Crowsons don't do quite as well on my concrete slab and style of my couch. I like to think of as the trampoline effect. My couch is a little different form the actual theater chairs that most of you guys are using. Its a three seat leather couch that has a metal rectangular frame on the bottom. I specifically bolted two BK LFE's in the middle, right under the MLP because it has a lot of flex and when they are cranked up, it makes me feel like I'm on a trampoline. Some may not like this and say its unrealistic/unnatural, but I love it and feel that it works well with what the Crowsons and nearfields add. I find that this effect is the strongest in the ~ 15 to 27ish hz range (where the BK's shine IMO, at least on my couch) and can be almost vision blurring when cranked up. Again, probably not the most natural and some may hate it, but I love it and find it works well, especially with the nearfields delivering the slam.

And then there are the Crowsons! Man I love these things as well. They are so realistic and can add a little that the nearfields alone sometimes don't IMO, like certain vibrations in the armrests, under 10hz stuff, etc (at least at moderate volumes with my set up and couch). My Crowson set up is probably not quite as optimal as coolrda's because of the style of my couch and only 2 vs his 4, but I still love them and will probably add 2 more eventually to help distribute the TR a little more evenly to each seat. I think that the Crowson experience would be the most optimum the way he has them set up on actual theater chairs with one on each back leg of each seat. I'm betting his Crowson setup really is killer! So I can definitely understand why he values them so much. They are awesome and I wouldn't want to be without them.

And last but definitely not least, the Nearfields! IMO they are awesome and I most definitely would not want to be without these! They can deliver serious Slam, TR, and PR all at the same time. I would choose them over the TT's if I had to make a choice. Luckily I don't have to choose and can use both!
So I had the house to myself for a couple hours this morning and did some experimenting with what the transducers in my system add to my nearfield subs. I wanted to add a bit more from my last post on what I feel the main differences are between the feel that I get between nearfield sub placement at my back and transducers. I wanted to be sure of no other influences so I calibrated just the triple sealed 18's (as one) that are right behind me firing into my back. I left the front sub completely out. I calibrated as flat as I could and then added in my usual LS at 24hz with a 9db Gain and a 1 Q so lift the lower end up post Audy.

First I'd like to say that my system has actually never sounded cleaner than with just the NF's running and no front end sub. Although I like what the front sub adds, I may rethink just how much I actually want it to contribute in my room. I like that it can pull the sound forward just a little bit more for a tad bit better bass envelopment. But with that said I could probably go without ever hooking that front sub up again and be very happy. Bass was still very enveloping and un localizable. It seemed like it was coming from everywhere. And bass was super clean and crisp - I think partially because the NF's are pretty much in the middle of the room (not up close to a wall) and don't really ever become boomy and bloated very easily, even when ran extremely hot. I can't say the same about my front sub as easily, even with a real nice FR. If I run it to hot to try to get more TR out of it, it just gets boomy way before I start getting the TR that I'm looking for in my room. So NF's and TT's are a god send for me, as I'm kind of a TR junkie LOL!

So on to the experiment:

Short version - the TT's (Crowsons and Buttkcker LFE's on the same couch) most definitely added to the experience for me! I would never want to give up either the NF's or TT's and feel they work extremely well together for my room and setup!

Longer version and details - I used Underworld Awakening for the demo material. Specifically the Large Lycon scene starting at 47:00 and the scene where they blow up the elevator starting at 1:03:20. It was kind of hard to choose because this whole movie has some of the most awesome bass ever in it IMO. I chose not to do the test at extremely loud listening levels because sometimes that can become numbing with massive amounts of slam and loudness from everything. I wanted to be able to hear and feel everything very precisely and sometimes this is easier for me to do at a little lower SPLs. I chose to listen at -15MV with the nearfield bank of subs only ran 2db hot (and no DEQ). There so much bass in this movie that any hotter and its just to much and starts over powering everything else, at least in my system. Other movies I can usually run my bass just a little hotter. I also like -15MV in my room because its still pretty loud and where I choose to listen a fair amount of the time.

So with both of these scenes, the bass just felt bone rattling (and super powerful and full) with the combination of the TT's and the NF subs slamming the crap out of me while at the same time all the details remained super crisp and clean to me (sound and feel wise). So here is where I felt the TT's really added to the experience - with the subs alone running, they deliver serious impact from the sound waves and pressure just smashing into the back of the couch and body. And while it shakes the couch very intensely and feels awesome on the body, it feels a bit different than what the TT's do, at least on these mega bass scenes like these. The TT's add more of an up and down and overall shake motion from the bottom under your butt more so than what the subs do. It's fantastic without the TT's, but with the TT's engaged it just adds yet another dimension of realistic and seamless TR that seems to be coming from everywhere that the NF subs alone don't do quite as well just by themselves. For me, they complete the bass experience and work extremely well together, making it feel super realistic and shockingly powerful, even at these lower listening levels.

Here was FR (subs crossed over at 90hz) of just the NF subs for the test.....
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post #4617 of 4663 Old 08-20-2016, 06:07 PM
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But, if you think we have a problem with global warming now, wait to @BassThatHz relocates his system outdoors.
Actually my theater is very energy efficient, because my walls are twice as thick as a normal exterior wall and twice as insulated. I have no leaks, no windows, and two sets of exterior doors.

The ceiling is like R-50, and the walls are like R-30.
Most doors are R-5, mine must be at least R-10.
My attic hatch is 3 times as thick as what you'd find in a normal house. 3/4 MDF + 5/8 X-DW+GG+5/8 X-DW

In the winter I don't have to turn on the heat, I just turn on the amplifiers.
It can be freezing outside and my room will be room temp with that. No additional greenhouse gases emitted.

It is 98 outside right now, but it's only 75 in my room, without the AC on.


If I don't play any bass in the summer I am more-green than most other structures.
The keyword is: if...
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post #4618 of 4663 Old 08-21-2016, 05:00 AM
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hornresp calculates particle velocity so I thought I'd see if I could find a way to compare the particle velocity produced by a sealed sub vs that produced by a port when the same SPL is produced. I'm not 100% sure this is accurate and it's only a sim but I'm not sure why it wouldn't be in the right ballpark (*waits for corrections* perhaps @LTD02 might have a view).

To do this I added a (very) short horn section in front of the sealed box so I could get it to calculate particle velocity at the exit from the horn. I suppose this is something like a NF sub which gets rammed up pretty close to the sofa so that airspace could be considered a lossy segment (I guess this might be better modelled as a lossy bandpass but anyway). I then created a ported sub using the same driver tuned to 19.5Hz, scaled the voltage to produce the same total SPL and then compared particle velocity from the port exit to the "horn" exit.

The grey line is the sealed sub, black the ported. 0.062m/2 vs 0.73m/s or about an order of magnitude greater particle velocity (SPL is ~85dB).



Obviously this doesn't answer how this scales to induced TR but I thought it might be interesting anyway.
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post #4619 of 4663 Old 08-21-2016, 09:50 AM
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the reason I was doing this was so I could attempt to compare a sealed (aggressively) LT'ed NF sub vs a smaller ported sub, sadly it seems like hornresp doesn't make this v easy though. I wonder if akabak or some other tool can do this?
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post #4620 of 4663 Old 08-21-2016, 10:09 AM - Thread Starter
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Originally Posted by 3ll3d00d View Post
hornresp calculates particle velocity so I thought I'd see if I could find a way to compare the particle velocity produced by a sealed sub vs that produced by a port when the same SPL is produced. I'm not 100% sure this is accurate and it's only a sim but I'm not sure why it wouldn't be in the right ballpark (*waits for corrections* perhaps @LTD02 might have a view).

To do this I added a (very) short horn section in front of the sealed box so I could get it to calculate particle velocity at the exit from the horn. I suppose this is something like a NF sub which gets rammed up pretty close to the sofa so that airspace could be considered a lossy segment (I guess this might be better modelled as a lossy bandpass but anyway). I then created a ported sub using the same driver tuned to 19.5Hz, scaled the voltage to produce the same total SPL and then compared particle velocity from the port exit to the "horn" exit.

The grey line is the sealed sub, black the ported. 0.062m/2 vs 0.73m/s or about an order of magnitude greater particle velocity (SPL is ~85dB).



Obviously this doesn't answer how this scales to induced TR but I thought it might be interesting anyway.
Wow...this is a great find!

This confirms the hypothesis that around tune, there is more PVL for the ported sub compared to sealed.

Given that Sound Intensity (SIL) = Particle Velocity (PVL) * Pressure (SPL):

If SPL is kept constant (like in the above), and PVL is greater, then following the equation, SIL or Sound Intensity MUST be greater.

Increased SIL has been indirectly measured by detecting increased vibration in an object (HT seating) via tools like VibSensor and the Vibration Meter in the ported vs sealed tests that have been conducted for the past few years.

Awesome @3ll3d00d.

Now, can we take this further? How large of a band is PVL increased? Can you sim that as well?

Also, can you compare a horn vs ported at tune and see if PVL differs between the two?

Last edited by dominguez1; 08-21-2016 at 10:13 AM.
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