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Simplified REW Setup and Use (USB Mic & HDMI Connection) Including Measurement Techniques and How... - Page 130

post #3871 of 9535

To be honest, you are causing a bit of frustration as well.  You keep saying it isn't working for you, yet you provide no details of what is going wrong. 

 

Here is what I am going to ask you to do.  Have the Guide open to follow along.  Ignore for a moment that the UMIK-1 is not supposed to require a manual calibration.

 

  1. Boot up the laptop.
  2. Plug in the USB mic and HDMI cable before launching REW.
  3. Verify that the HDMI is your default output device (page 8).
  4. Verify that the UMIK-1 is your default input device (page 20).
  5. Verify the UMIK-1 level is set to 100 (page 23).
  6. Launch REW.
  7. Follow the instructions in "Step 5:  REW Microphone Calibration" to the letter, again ignoring that the UMIK-1 should not require a calibration.
  8. If during Step 5, anything does not match what is supposed to happen according to the procedure, make a note of it (or better yet, take a screen shot).

 

At the end of Step 5, your mic should be working properly.  By "working properly", I mean that REW should be producing a test tone at a level of approximately 80dB with an AVR master volume setting somewhere in the -10 to -20 range.

 

If the mic is still not working properly, then this is a test of your ability to accurately communicate why the procedure is not working.  It is not out of the question that you could have a malfunctioning piece of equipment, either the mic or the laptop.

Gear mentioned in this thread:

post #3872 of 9535
Quote:
Originally Posted by AustinJerry View Post

To be honest, you are causing a bit of frustration as well.  You keep saying it isn't working for you, yet you provide no details of what is going wrong. 


Sorry to frustrate you. I don't know how much clearer I can be. Let me try:

The noise floor on my mic is reading 25. You state in the manual it should be ~50.
At one point I had the ~50 noise floor reading and I could calibrate the SPL meter as you instruct.
Because the noise floor is low, obtaining your recommended calibration level of 80 is impossible without raising AVR volume past volumes that are too high.
post #3873 of 9535
Ok. My first measurement High Noise Floor:







cool.gif
post #3874 of 9535
Quote:
Originally Posted by pdxrealtor View Post


Sorry to frustrate you. I don't know how much clearer I can be. Let me try:

The noise floor on my mic is reading 25. You state in the manual it should be ~50.
At one point I had the ~50 noise floor reading and I could calibrate the SPL meter as you instruct.
Because the noise floor is low, obtaining your recommended calibration level of 80 is impossible without raising AVR volume past volumes that are too high.

 

If you follow the steps recommended in my previous post, I will try and help.

post #3875 of 9535
Does this look right?

Left speaker - full range, no subs and no Audyssey (AVR at -30 dB):








Average speaker - full range, no subs and no Audyssey (AVR at -30 dB):




Edited by cr136124 - 7/2/13 at 3:03pm
post #3876 of 9535

^ Your measurement technique looks good.  The actual response curves show some issue, which I am sure you have already concluded as well.  Subs, treatments, and room correction would smooth the response out.

post #3877 of 9535
Quote:
Originally Posted by AustinJerry View Post

^ Your measurement technique looks good.  The actual response curves show some issue, which I am sure you have already concluded as well.  Subs, treatments, and room correction would smooth the response out.

Thanks for the confirmation!

Yep, I can see the big fluctuations deep and peak mainly on the left channel. Now, how exactly can I fix this issue?

I kept reading on your REW 101 document and I'm looking at the first reflections. Here is what I was able to measure:












You wouldn't believe me, but I don't have any string at home....................mad.gif
Edited by cr136124 - 7/2/13 at 4:02pm
post #3878 of 9535
Quote:
Originally Posted by AustinJerry View Post

To be honest, you are causing a bit of frustration as well.  You keep saying it isn't working for you, yet you provide no details of what is going wrong. 

Here is what I am going to ask you to do.  Have the Guide open to follow along.  Ignore for a moment that the UMIK-1 is not supposed to require a manual calibration.
  1. Boot up the laptop.
  2. Plug in the USB mic and HDMI cable before launching REW.
  3. Verify that the HDMI is your default output device (page 8).
  4. Verify that the UMIK-1 is your default input device (page 20).
  5. Verify the UMIK-1 level is set to 100 (page 23).
  6. Launch REW.
  7. Follow the instructions in "Step 5:  REW Microphone Calibration" to the letter, again ignoring that the UMIK-1 should not require a calibration.
  8. If during Step 5, anything does not match what is supposed to happen according to the procedure, make a note of it (or better yet, take a screen shot).

At the end of Step 5, your mic should be working properly.  By "working properly", I mean that REW should be producing a test tone at a level of approximately 80dB with an AVR master volume setting somewhere in the -10 to -20 range.

If the mic is still not working properly, then this is a test of your ability to accurately communicate why the procedure is not working.  It is not out of the question that you could have a malfunctioning piece of equipment, either the mic or the laptop.

Setting the UMIK-1 to 100 places REW readings out of whack. Example - I have a setting that I will use from now on .... it's AVR -10, Mic level 25. Upping the mic level to 100 just makes REW tell me I'm clipping then shows me a graph with higher DBs,....... but in reality the speaker output volume remains the same.

For whatever reason calibrating the SPL meter to 80 is'nt happening on my setup. I just skip SPL calibration every time, and use AVR -10 and Mic level 25. Until I need to know TRUE SPL I don't see this as being a problem.

For whatever reason it's just not happening with my setup. Redmere HDMI cable? Laptop? Mic? I don't know. I do know one thing, it's not because I'm not following your instructions to a T.

One good thing out doing the instructions several times over is I'm now very familiar with the setup process. wink.gif
post #3879 of 9535
Quote:
Originally Posted by cr136124 View Post

Thanks for the confirmation!

Yep, I can see the big fluctuations deep and peak mainly on the left channel. Now, how exactly can I fix this issue?

You are getting ahead of yourself. Reflections, which is what the ETC graph shows, have nothing to do with the smoothness of the frequency response. So forget about ETC measurements for now.

You need to work on the low frequency response first. The approach consists of several steps:

1. Consider adding one or more subs. Main speakers are positioned to provide optimal imaging, not optimal bass response. You can't move main speakers around looking for the smoothest bass response.
2. Unce you have one or more subs, set the main speakers to "small", which routes bass frequencies below the crossover point to the sub(s). Then use REW to find the best spot for the sub(s), the one that produces the most improvement in the bass response.

Depending on the results, there are several other steps to take, including room treatments, and room correction (DSP). But, if you are unwilling to add a sub, there isn't much you can do to improve upon what you have.
post #3880 of 9535
Quote:
Originally Posted by pdxrealtor View Post

Setting the UMIK-1 to 100 places REW readings out of whack. Example - I have a setting that I will use from now on .... it's AVR -10, Mic level 25. Upping the mic level to 100 just makes REW tell me I'm clipping then shows me a graph with higher DBs,....... but in reality the speaker output volume remains the same.

For whatever reason calibrating the SPL meter to 80 is'nt happening on my setup. I just skip SPL calibration every time, and use AVR -10 and Mic level 25. Until I need to know TRUE SPL I don't see this as being a problem.

For whatever reason it's just not happening with my setup. Redmere HDMI cable? Laptop? Mic? I don't know. I do know one thing, it's not because I'm not following your instructions to a T.

One good thing out doing the instructions several times over is I'm now very familiar with the setup process. wink.gif

I honestly don't understand what is causing the issues you are reporting, and no one else who participates in this thread is having the same issues. I am at a loss until I get the UMIK-1 mic that I have placed on order. According to CSL, the mics are on back order, so I don't know when mine will be arriving.
post #3881 of 9535
Quote:
Originally Posted by AustinJerry View Post

I honestly don't understand what is causing the issues you are reporting, and no one else who participates in this thread is having the same issues. I am at a loss until I get the UMIK-1 mic that I have placed on order. According to CSL, the mics are on back order, so I don't know when mine will be arriving.

Ya... I don't know man. It has something to do with the floor level though. Sure about that.

For some reason my mic is not hitting the 40-50db floor level no matter what.

Maybe it is a mic problem. Remember I posted I was stuck a 99db floor level and gave up for the night? That was just prior to it working at the calibrated 80 per your instructions. I ended up resetting the preferences and haven't gotten a floor level above 30 since.

If I figure it out I will post up. Kind of hard to spend time figuring it out when I can use the same AVR and Mic level settings and get the same result.
post #3882 of 9535
Quote:
Originally Posted by AustinJerry View Post

Quote:
Originally Posted by Saturn94 View Post

Last night I got a chance to measure my sub in different locations using REW. It was certainly very educational and it was obvious that the front left corner where my sub has resided for the past 10 years is the best spot available. My placement options are pretty much limited to said corner and either side of the couch (main LP).

This brings up a question. Is it possible to use this information to extrapolate how adding a second sub to either end of the couch, or even two subs one on each side for a total of three, would perform in my room? Is it a simple matter of overlaying the graphs to come up with a good approximation of the resulting curve? I realize the arrival times at the LP from each sub factors in here, but since phase can be adjusted, I'm thinking that shouldn't be such an issue.

Can someone explain to me in laymans terms how the response for multiple subs come together to form a single response?

I've never tried a multiple sub setup, but I don't want to buy two subs only to have to return one because it simply won't work with my limited placement options. I'm hoping I can use my existing data to make a fair prediction of what I can expect.

Thanks. smile.gif

 

I can provide a real-world example below of how adding subs results in improved bass response:

 

 

 

 

 

 

 

Two conclusions:

 

1.  Adding subs always improves the bass response.

2.  You can never have too much woofage (a quote from our friend across the water)  wink.gif

 

1. The graphs really show the impact of adding subs!

 

2. Never has a truer word been spoken (or typed) ;)

post #3883 of 9535


Not to dismiss the advantages of multiple subs one bit, but the above is what i am getting with a single sub (at 1/24th oct smoothing) that crosses over at 40hz.
post #3884 of 9535

Not bad, Jim, but where is the fun in that?  wink.gif

 

Your mains have a pretty good low end reach.

post #3885 of 9535
Quote:
Originally Posted by pdxrealtor View Post

The noise floor on my mic is reading 25. You state in the manual it should be ~50.
At one point I had the ~50 noise floor reading and I could calibrate the SPL meter as you instruct.
Because the noise floor is low, obtaining your recommended calibration level of 80 is impossible without raising AVR volume past volumes that are too high.
To manually calibrate the REW SPL meter you need a separate, handheld meter at the same location as the mic. You set the AVR volume to a comfortable level, that produces a 75 dB (or 80 if you prefer) reading on the separate handheld meter then type the figure that external meter reads into the REW cal box. After that the REW SPL meter should match the reading on the external meter (when the mic and the external meter are at the same place, of course).
post #3886 of 9535
Ok I tested out a pair of bookshelf speakers crossed at 90hz. Im am sure I did nothing right...


1st is with Audyssey on, 2nd with Audyssey off

Edited by jlpowell84 - 7/3/13 at 9:02pm
post #3887 of 9535
Quote:
Originally Posted by jlpowell84 View Post

Ok I tested out a pair of bookshelf speakers crossed at 90hz. Im am sure I did nothing right...


1st is with Audyssey on, 2nd with Audyssey off

 

It would help to view the graph more easily if you set the left and right limits to the range you are examining - in this case it seems to be 60-300Hz. 

 

When you take measurements, always take the full range from 15Hz to 20,000Hz. REW lets you then examine any part more closely later, by setting the limits as above.

 

If you re-post your graphs with those adjustments it will make it easier to comment. Can you also tell us which speakers or combination of speakers you were testing?  Are the above graphs R + L without subs?  If so, why did you only measure the 60-300Hz range?  If they are bookshelf speakers it would be more usual to measure their entire range up to 20,000Hz. For full range graphs, use 1/6th smoothing. For bass frequency graphs, use no smoothing, or if that makes the graph difficult to see, 1/48th might help.

post #3888 of 9535
Quote:
Originally Posted by kbarnes701 View Post

It would help to view the graph more easily if you set the left and right limits to the range you are examining - in this case it seems to be 60-300Hz. 

When you take measurements, always take the full range from 15Hz to 20,000Hz. REW lets you then examine any part more closely later, by setting the limits as above.

If you re-post your graphs with those adjustments it will make it easier to comment. Can you also tell us which speakers or combination of speakers you were testing?  Are the above graphs R + L without subs?  If so, why did you only measure the 60-300Hz range?  If they are bookshelf speakers it would be more usual to measure their entire range up to 20,000Hz. For full range graphs, use 1/6th smoothing. For bass frequency graphs, use no smoothing, or if that makes the graph difficult to see, 1/48th might help.

Yea I thought if I set to 60hz then it would not do a full sweep. I was using Definitive Technology pro monitor 1000's. No sub. I actually just unhooked my whole setup and have sold my main towers and my HSU sub. I have been spending lots of time in the subwoofer forums and JTR threads. I have resorted that I am going to go straight to the top with my purchases and cut out the cycle of upgrades I have observed many do. Looking at JTR Noesis 212 L/C/R and Dual Captivator S2's. anyway I hooked up my AVR and two PM 1000's, previously surrounds, so I can still take measurements and learn REW until everything comes together.
post #3889 of 9535
Quote:
Originally Posted by jlpowell84 View Post

Quote:
Originally Posted by kbarnes701 View Post

It would help to view the graph more easily if you set the left and right limits to the range you are examining - in this case it seems to be 60-300Hz. 

When you take measurements, always take the full range from 15Hz to 20,000Hz. REW lets you then examine any part more closely later, by setting the limits as above.

If you re-post your graphs with those adjustments it will make it easier to comment. Can you also tell us which speakers or combination of speakers you were testing?  Are the above graphs R + L without subs?  If so, why did you only measure the 60-300Hz range?  If they are bookshelf speakers it would be more usual to measure their entire range up to 20,000Hz. For full range graphs, use 1/6th smoothing. For bass frequency graphs, use no smoothing, or if that makes the graph difficult to see, 1/48th might help.

Yea I thought if I set to 60hz then it would not do a full sweep. I was using Definitive Technology pro monitor 1000's. No sub. I actually just unhooked my whole setup and have sold my main towers and my HSU sub. I have been spending lots of time in the subwoofer forums and JTR threads. I have resorted that I am going to go straight to the top with my purchases and cut out the cycle of upgrades I have observed many do. Looking at JTR Noesis 212 L/C/R and Dual Captivator S2's. anyway I hooked up my AVR and two PM 1000's, previously surrounds, so I can still take measurements and learn REW until everything comes together.

 

Going straight to the top is probably the best decision you will ever make wrt to your HT. The constant 'upgrading' is an expensive way to do it for sure, not to mention all the hassle every time. Certainly one of the biggest possible bangs for your buck will be learning to use REW and applying acoustic treatments based on what you discover. Once the room is improved, the sound is so much better that a lot of the constant urge to 'upgrade' just goes away.

 

Have you considered Seaton Submersives for the woofage?  I am totally blown away by my pair - even so long after getting them I still marvel at how amazing they are. Have a look at the Submersive thread here on AVS - you won’t find a single SubM owner who says anything negative about them. Just a thought.

post #3890 of 9535
Quote:
Originally Posted by jlpowell84 View Post


Yea I thought if I set to 60hz then it would not do a full sweep. I was using Definitive Technology pro monitor 1000's. No sub. I actually just unhooked my whole setup and have sold my main towers and my HSU sub. I have been spending lots of time in the subwoofer forums and JTR threads. I have resorted that I am going to go straight to the top with my purchases and cut out the cycle of upgrades I have observed many do. Looking at JTR Noesis 212 L/C/R and Dual Captivator S2's. anyway I hooked up my AVR and two PM 1000's, previously surrounds, so I can still take measurements and learn REW until everything comes together.

 

Just curious, if you are going with Captivator subs with dual 18" drivers, why are you spending so much money on the main speakers, which also have dual 12" drivers?  Won't you be letting the Captivators handle the bass frequencies below ~80Hz?

post #3891 of 9535
Quote:
Originally Posted by AustinJerry View Post

Just curious, if you are going with Captivator subs with dual 18" drivers, why are you spending so much money on the main speakers, which also have dual 12" drivers?  Won't you be letting the Captivators handle the bass frequencies below ~80Hz?

Well the vented 212 Noesis is designed to be crossed 60 and up, and the sealed 70 and up. I haven't thought about that yet Jerry. I guess it seems the 12's in the mains are designed strictly for mid bass? That's an interesting point, perhaps I will ask. I just assumed that I am already invested a bunch if I went with the 8's why not go a little more for the best.

Keith, yes the Submersives are in the mix. Also the Orbit Shifters but i like the smaller footprint idea, although i would be willing. It just seems why not jump a little more for 18's and a 4kw amp. A single S2 has 127 db output which would be more than i would ever need. I have read much on comparisons as far as SQ which is very important. Many say they couldn't tell the difference as far as the "bigger drivers are slower," myth/argument. Even guys who have owned both seatons and JTR's.
post #3892 of 9535
Quote:
Originally Posted by jlpowell84 View Post

Well the vented 212 Noesis is designed to be crossed 60 and up, and the sealed 70 and up. I haven't thought about that yet Jerry. I guess it seems the 12's in the mains are designed strictly for mid bass? That's an interesting point, perhaps I will ask. I just assumed that I am already invested a bunch if I went with the 8's why not go a little more for the best.

Keith, yes the Submersives are in the mix. Also the Orbit Shifters but i like the smaller footprint idea, although i would be willing. It just seems why not jump a little more for 18's and a 4kw amp. A single S2 has 127 db output which would be more than i would ever need. I have read much on comparisons as far as SQ which is very important. Many say they couldn't tell the difference as far as the "bigger drivers are slower," myth/argument. Even guys who have owned both seatons and JTR's.

Did you looked at PSA Triax?
post #3893 of 9535
Quote:
Originally Posted by mp5475 View Post

Did you looked at PSA Triax?

I've looked at it once. Actually I think they are the same amps. There is plenty of time, more than half year. Plenty of time to learn
post #3894 of 9535

UMIK-1 Microphone

 

I have received, installed and tested my UMIK-1 mic.  I also updated the Guide with a section specifically for UMIK-1 users.  However, I cannot upload files to AVS right now.  The issue has been reported to Forum Operations.

 

In the meantime, if you need the UMIK-1 information, send me a PM.

 

post #3895 of 9535
What is your floor level? And is it the same consistently?
post #3896 of 9535
Quote:
Originally Posted by pdxrealtor View Post

What is your floor level? And is it the same consistently?

 

Consistently around 50dB, which is the expected value.  Are you seeing something different?

post #3897 of 9535
Jerry and Keith Ive finally done the measures with REW. I really wouldn't have a clue if I did them correctly or not as I found it a bit intimidating following all the instructions but I feel Ive done it all correctly.

I first did the centre row of the three. Remember I have four SVS SB13-Ultras up front and two Velodyne 12" in the back row. I did centre + sub, left + sub and right + sub.
I did the back row next and the front row last. Remember the three rows are over risers so we are dealing with different heights over the three readings.

post #3898 of 9535
I don't know whats up with this site but Im having trouble trying to add images to the same post, here are the rest.rolleyes.gif





Edited by RapalloAV - 7/7/13 at 11:45pm
post #3899 of 9535
Quote:
Originally Posted by RapalloAV View Post

I don't know whats up with this site but Im having trouble trying to add images to the same post, here are the rest.rolleyes.gif




 

Couple of housekeeping points - can you make the X-axis scale in increments of 5dB,  just to make it easier for us to compare at a glance, and can you post graphs of R+L + Subs for the full range measurement, which is what we are used to using?

 

The front and middle rows don't look bad, assuming that big bass boost is what you want. The back row is pretty disastrous by comparison, but we expected that. Personally, I'd like to see the bass rising more smoothly from the crossover region to about 30Hz and then dropping off gradually or remaining flat for as long as the subs can hold it.  But to achieve that you'd probably have to go into the realms of PEQ and that is a whole new rabbit hole. If it sounds good as things stand, and accepting that you will probably never get all three rows to be equally good, how do you think it looks so far?

post #3900 of 9535
Quote:
Originally Posted by kbarnes701 View Post

Couple of housekeeping points - can you make the X-axis scale in increments of 5dB,  just to make it easier for us to compare at a glance, and can you post graphs of R+L + Subs for the full range measurement, which is what we are used to using?

The front and middle rows don't look bad, assuming that big bass boost is what you want. The back row is pretty disastrous by comparison, but we expected that. Personally, I'd like to see the bass rising more smoothly from the crossover region to about 30Hz and then dropping off gradually or remaining flat for as long as the subs can hold it.  But to achieve that you'd probably have to go into the realms of PEQ and that is a whole new rabbit hole. If it sounds good as things stand, and accepting that you will probably never get all three rows to be equally good, how do you think it looks so far?

I really don't know how it looks so far sorry Keith, its beyond my knowledge.

I don't even know how to give you the other things you ask for sorry....
can you make the X-axis scale in increments of 5dB, just to make it easier for us to compare at a glance, and can you post graphs of R+L + Subs for the full range measurement, which is what we are used to using?

Im really pretty satisfied with the sound to be truthful. I just want to know if I have the subs in the best positions before I close in the stage area and build the rear subs into the floor since they are floor subs.
Edited by RapalloAV - 7/8/13 at 2:16am
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