Simplified REW Setup and Use (USB Mic & HDMI Connection) Including Measurement Techniques and How To Interpret Graphs - Page 966 - AVS Forum | Home Theater Discussions And Reviews
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post #28951 of 29017 Old 03-26-2020, 01:56 PM
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Quote:
Originally Posted by AustinJerry View Post
Wow, 25ft is a pretty big distance. Is this coming from Audyssey? Do you have an exceptionally large room?

You say you are using two MiniDSP HD’s. I assume you mean 2x4HD’s, correct? Each sub channel on the 2x4HD should have a delay setting. To use the 2x4HD to perform the sub distance tweak, vary each sub delay by the same amount, which will preserve any sub-to-sub timing you may have already set up.
Hope this isn’t a stupid question but when I change the delays in my minidsp’s do I also change the one with no delay? I’d assume yes but just making sure.

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post #28952 of 29017 Old 03-26-2020, 01:59 PM
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Originally Posted by mcallister View Post
Hope this isn’t a stupid question but when I change the delays in my minidsp’s do I also change the one with no delay? I’d assume yes but just making sure.
No question is ever stupid. Yes, add or subtract the same amount from all sub distances—this preserves the sub-to-sub time alignment.
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post #28953 of 29017 Old 03-26-2020, 02:01 PM
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The latest version of the REW guide linked in my sig has a new section describing FlexASIO as an alternative to ASIO4All. You might want to give it a try to see if it fixes your issues.
thank you. i already tryed with your guide and flexasio but i dont understand how to opern "flexaudio control panel".

i have downloaded the installer and loaded it on rew but when i click on "asio panel" it opens a webpage with the instructions. there are other instructions not included in your guide.


EDIT: NOW WORKS WITH FLEXASIO!! THANK YOU DUDE!

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post #28954 of 29017 Old 03-26-2020, 03:26 PM
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Originally Posted by jeeldo View Post
thank you. i already tryed with your guide and flexasio but i dont understand how to opern "flexaudio control panel".

i have downloaded the installer and loaded it on rew but when i click on "asio panel" it opens a webpage with the instructions. there are other instructions not included in your guide.


EDIT: NOW WORKS WITH FLEXASIO!! THANK YOU DUDE!
Glad it worked for you. I have not used FlexASIO enough to be able to provide troubleshooting help.
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post #28955 of 29017 Old 03-26-2020, 07:00 PM
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Hi
Please can someone answer these questions about eq mains only.
This is my process with REW:
Measure both mains combined.
Measure left main
Measure right main
Use Var smoothing in REW.
Eq both combined 20-250hz (same filters for both mains), if there are 1 or more filters that are different in this range I use seperate filters
250hz up seperate filters for left and right speakers, with small Q e.g no more than 3 Q.

Am I on the right track.

Thanks
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post #28956 of 29017 Old 03-26-2020, 08:23 PM
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Quote:
Originally Posted by Philips752 View Post
Hi
Please can someone answer these questions about eq mains only.
This is my process with REW:
Measure both mains combined.
Measure left main
Measure right main
Use Var smoothing in REW.
Eq both combined 20-250hz (same filters for both mains), if there are 1 or more filters that are different in this range I use seperate filters
250hz up seperate filters for left and right speakers, with small Q e.g no more than 3 Q.

Am I on the right track.

Thanks
Just curious, what device are you loading the PEQ into? If the device allows for separate PEQ for left and right channels, then I would measure the left and right speakers independently and develop PEQ for each channel.
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post #28957 of 29017 Old 03-26-2020, 10:57 PM
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Quote:
Originally Posted by AustinJerry View Post
Quote:
Originally Posted by Philips752 View Post
Hi
Please can someone answer these questions about eq mains only.
This is my process with REW:
Measure both mains combined.
Measure left main
Measure right main
Use Var smoothing in REW.
Eq both combined 20-250hz (same filters for both mains), if there are 1 or more filters that are different in this range I use seperate filters
250hz up seperate filters for left and right speakers, with small Q e.g no more than 3 Q.

Am I on the right track.

Thanks
Just curious, what device are you loading the PEQ into? If the device allows for separate PEQ for left and right channels, then I would measure the left and right speakers independently and develop PEQ for each channel.
Hi Austin Jerry thank you.
Using Dspeaker Antimode 2.0.
Yes it does allow separate filters. These are in REW.
It has think 16 filters per side, full frequency range on top of automatic filters.
It also has stereo filters so you can load for both channels under one filter slot.
Has four different slots (A, B, C, D) for different curves.
Has other features too.

I am trying to set all manual, just playing to see if I can beat the automatic, although automatic only goes as high as 500hz which is ok.
Has quite a bit in it, not many people play.

Thanks
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post #28958 of 29017 Old 03-29-2020, 08:12 AM
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I am Just getting started with REW using an old MacBook laptop with a Dayton UMM-6 microphone. Is REW supposed to auto detect the microphone? I have downloaded the cal file and added loaded it into REW. I thought I wouldn’t need an SPL calibration, but it seems that it is required? Is this expected? I am using the latest beta of REW and HDMI out to my AVR. I also have an old SPL meter I can use for the SPL calibration so it’s not an issue.

As an aside, I am trying to verify the results Audyssey gave me and if I just want to check things, should I turn off Audyssey dynamic EQ? Anything else is should disable in Audyssey to get a clear idea of what is going on?

Thank you!
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post #28959 of 29017 Old 03-29-2020, 09:17 AM
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Quote:
Originally Posted by UMD_Terp View Post
I am Just getting started with REW using an old MacBook laptop with a Dayton UMM-6 microphone. Is REW supposed to auto detect the microphone? I have downloaded the cal file and added loaded it into REW. I thought I wouldn’t need an SPL calibration, but it seems that it is required? Is this expected? I am using the latest beta of REW and HDMI out to my AVR. I also have an old SPL meter I can use for the SPL calibration so it’s not an issue.

As an aside, I am trying to verify the results Audyssey gave me and if I just want to check things, should I turn off Audyssey dynamic EQ? Anything else is should disable in Audyssey to get a clear idea of what is going on?

Thank you!
Missing information:

- Are you using HDMI with ASIO, or the Java drivers?
- Are you using a calibration file with a sensitivity parameter for the UMM-6? (Open the file in a text editor and check for the sensitivity parameter in the first line).
- In REW’s SPL meter, when you click on “Calibrate”, does it say no calibration required? If no, then proceed with mic calibration.

When measuring Audyssey results, one would typically turn off DynamicEQ and Dynamic Volume.
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post #28960 of 29017 Old 03-29-2020, 09:50 AM
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Quote:
Originally Posted by AustinJerry View Post
Missing information:

- Are you using HDMI with ASIO, or the Java drivers?
- Are you using a calibration file with a sensitivity parameter for the UMM-6? (Open the file in a text editor and check for the sensitivity parameter in the first line).
- In REW’️s SPL meter, when you click on “Calibrate”, does it say no calibration required? If no, then proceed with mic calibration.

When measuring Audyssey results, one would typically turn off DynamicEQ and Dynamic Volume.
This is on my MacBook and I have not installed any drivers in addition to REW. Under the MIDI Audio setup I’ve enabled 5.1 speakers and those show up in REW enumerated properly.

The cal file for the umm-6 has a “SENS FACTOR” listed on the first line.

REW does not prompt me to say that calibration isn’t required. I’ve tried to cal it with my SPL meter and it seems to get close.

I have dynamic volume disabled but i will disable dynamic EQ as well.

I ran a sweep L+R with dynamic EQ enabled and it seems that the sub is about 10dB hot relative to the mains.

Thank you again for the help!
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post #28961 of 29017 Old 03-29-2020, 02:56 PM
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OK I was able to reformat the calibration file that I had for the microphone. The first line in the file was

“SENS FACTOR =-19.132dB, SERNO xxxxx”

followed by the frequency, gain, phase points.

I just changed the first line to read:

Sensitivity -19.132 dBFS

that seemed to do the trick. Now it seems that the SPL is calibrated as indicated by the white numbering in the SPL Meter and I don’t get the message to calibrate SPL when doing a measurement.
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post #28962 of 29017 Old 03-29-2020, 03:51 PM
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Originally Posted by UMD_Terp View Post
OK I was able to reformat the calibration file that I had for the microphone. The first line in the file was

“SENS FACTOR =-19.132dB, SERNO xxxxx”

followed by the frequency, gain, phase points.

I just changed the first line to read:

Sensitivity -19.132 dBFS

that seemed to do the trick. Now it seems that the SPL is calibrated as indicated by the white numbering in the SPL Meter and I don’t get the message to calibrate SPL when doing a measurement.
Sorry, this make no sense to me. The first line of my calibration file is "Sens Factor =-6.352dB, SERNO: xxx", which is how it came from MiniDSP. When I change the first line to be formatted the way you show and then click the "Calibrate" button, it allows me to calibrate the mic. This means it is not recognizing the sensitivity parameter. So, I don't agree with your findings and you should click on the "Cal Files" tab--there are several boxes for calibration files. Check to see if the old cal file is still in use.

Edit: Check page 46 in the REW guide linked in my sig. BTW, you posted a measurement earlier, and it seemed REW was working properly. What prompted you to change the format of the line with the sensitivity parameter?

Last edited by AustinJerry; 03-29-2020 at 03:59 PM.
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post #28963 of 29017 Old 03-29-2020, 08:48 PM
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Quote:
Originally Posted by AustinJerry View Post
Sorry, this make no sense to me. The first line of my calibration file is "Sens Factor =-6.352dB, SERNO: xxx", which is how it came from MiniDSP. When I change the first line to be formatted the way you show and then click the "Calibrate" button, it allows me to calibrate the mic. This means it is not recognizing the sensitivity parameter. So, I don't agree with your findings and you should click on the "Cal Files" tab--there are several boxes for calibration files. Check to see if the old cal file is still in use.

Edit: Check page 46 in the REW guide linked in my sig. BTW, you posted a measurement earlier, and it seemed REW was working properly. What prompted you to change the format of the line with the sensitivity parameter?

I think I found somewhere on the internet where I cam across that syntax... I think REW is working fine, I just wanted to understand why it wasn't recognizing the sensitivity in my original calibration file. I went and deleted the install and all the preferences, re-intstalled, and set the cal file in multiple boxes for the mic but that still doesn't work to get the sensitivity read. From all the instructions I've seen, REW should prompt me that it found a USB microphone and then ask for the calibration file. That is what isn't happening for me. The mic shows up in the drop down menu under preferences, but isn't being auto-detected on start-up.
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post #28964 of 29017 Old 03-29-2020, 09:05 PM
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Originally Posted by UMD_Terp View Post
I think I found somewhere on the internet where I cam across that syntax... I think REW is working fine, I just wanted to understand why it wasn't recognizing the sensitivity in my original calibration file. I went and deleted the install and all the preferences, re-intstalled, and set the cal file in multiple boxes for the mic but that still doesn't work to get the sensitivity read. From all the instructions I've seen, REW should prompt me that it found a USB microphone and then ask for the calibration file. That is what isn't happening for me. The mic shows up in the drop down menu under preferences, but isn't being auto-detected on start-up.
The point I made in my previous post is that your modified syntax is not correct. Re-download the file from the Dayton Audio web site to see what the correct syntax is. And REW does not always prompt fro a mic calibration file if one is already configured. Regardless, if you are confident REW is working properly, all is good.
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post #28965 of 29017 Old 03-29-2020, 09:53 PM
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Hi please help me set-up on a old computer XP laptop, very low powered.

Sorry can't post photos.

Mic is a Omnimic V2
Java 7 installed
REW V5. 15 beta 7

Problem is get inconsistent on the low frequencies, also headroom only gets to 26db ish when measurement is taken with these settings. Check levels only produce 38ish dbFS on the input.

Preferences:
Sample Rate 48khz
Output Device = Conexant AMC Audio
Output = Speaker Left
Buffer = 32
Ticked box Control output mixer/volume
Output volume 0.631
Sweep level - 12.0

Input Device = Omnimic
Input = Microphone Left
Buffer = 32
Ticked box = Control input mixer /volume
Input volume 0.750

Is the buffer ok?

Thanks in advance

Last edited by Philips752; 03-30-2020 at 01:24 AM. Reason: Add data
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post #28966 of 29017 Old 03-30-2020, 04:16 AM
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Quote:
Originally Posted by UMD_Terp View Post
I think I found somewhere on the internet where I cam across that syntax... I think REW is working fine, I just wanted to understand why it wasn't recognizing the sensitivity in my original calibration file. I went and deleted the install and all the preferences, re-intstalled, and set the cal file in multiple boxes for the mic but that still doesn't work to get the sensitivity read. From all the instructions I've seen, REW should prompt me that it found a USB microphone and then ask for the calibration file. That is what isn't happening for me. The mic shows up in the drop down menu under preferences, but isn't being auto-detected on start-up.
The dBFS format for sensitivity data is for analog mics, it does not take account of input volume setting so is probably resulting in incorrect readings with the UMM-6. Please attach a copy of the file REW generates when you use the Generate debug file button on the soundcard preferences.
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post #28967 of 29017 Old 03-30-2020, 05:53 AM
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The dBFS format for sensitivity data is for analog mics, it does not take account of input volume setting so is probably resulting in incorrect readings with the UMM-6. Please attach a copy of the file REW generates when you use the Generate debug file button on the soundcard preferences.
I went back to the original calibration file I downloaded. The debug file is attached to this message. Thanks for the help!
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post #28968 of 29017 Old 03-30-2020, 06:20 AM
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Originally Posted by UMD_Terp View Post
I went back to the original calibration file I downloaded. The debug file is attached to this message. Thanks for the help!
The format of the mic name in the mixer list is the problem, it appears as "UMM_6" instead of "UMM-6". I'll make a change to recognise both versions for the next beta.
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post #28969 of 29017 Old 03-30-2020, 06:44 AM
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Originally Posted by JohnPM View Post
The format of the mic name in the mixer list is the problem, it appears as "UMM_6" instead of "UMM-6". I'll make a change to recognise both versions for the next beta.
Cool! Thank you!
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post #28970 of 29017 Old 03-30-2020, 06:56 AM
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Quote:
Originally Posted by Philips752 View Post
Hi please help me set-up on a old computer XP laptop, very low powered.

Sorry can't post photos.

Mic is a Omnimic V2
Java 7 installed
REW V5. 15 beta 7

Problem is get inconsistent on the low frequencies, also headroom only gets to 26db ish when measurement is taken with these settings. Check levels only produce 38ish dbFS on the input.

Preferences:
Sample Rate 48khz
Output Device = Conexant AMC Audio
Output = Speaker Left
Buffer = 32
Ticked box Control output mixer/volume
Output volume 0.631
Sweep level - 12.0

Input Device = Omnimic
Input = Microphone Left
Buffer = 32
Ticked box = Control input mixer /volume
Input volume 0.750

Is the buffer ok?

Thanks in advance
Sorry, it is difficult to provide guidance for your setup. You are using an operating system that is no longer supported. REW v5.15 beta 7 is not the current version. You are using a mic different from what most of us are using. And it is difficult to troubleshoot issues with the Java drivers when many of us have been using the HDMI interface for quite a while.

Did you calibrate the mic?
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post #28971 of 29017 Old 03-30-2020, 11:26 AM
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Quote:
Originally Posted by AustinJerry View Post
Quote:
Originally Posted by Philips752 View Post
Hi please help me set-up on a old computer XP laptop, very low powered.

Sorry can't post photos.

Mic is a Omnimic V2
Java 7 installed
REW V5. 15 beta 7

Problem is get inconsistent on the low frequencies, also headroom only gets to 26db ish when measurement is taken with these settings. Check levels only produce 38ish dbFS on the input.

Preferences:
Sample Rate 48khz
Output Device = Conexant AMC Audio
Output = Speaker Left
Buffer = 32
Ticked box Control output mixer/volume
Output volume 0.631
Sweep level - 12.0

Input Device = Omnimic
Input = Microphone Left
Buffer = 32
Ticked box = Control input mixer /volume
Input volume 0.750

Is the buffer ok?

Thanks in advance
Sorry, it is difficult to provide guidance for your setup. You are using an operating system that is no longer supported. REW v5.15 beta 7 is not the current version. You are using a mic different from what most of us are using. And it is difficult to troubleshoot issues with the Java drivers when many of us have been using the HDMI interface for quite a while.

Did you calibrate the mic?
.

Hi Austin Jerry mic is calibrated with the sens value.
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post #28972 of 29017 Old 03-30-2020, 12:04 PM
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Okay, so I finally got around to rerunning sweeps & room calibration (THANKS RONA!! ) after replacing the drivers in my CC, and was wondering what y'all would suggest as far as EQ'ing this sub measurement.

I'm attaching the Post Audy sweep and a compresssion sweep for reference.


Thanks for any/all help,

Darrell
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post #28973 of 29017 Old 03-31-2020, 05:40 PM
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Can REW do timing via MiniDSP 2x4HD USB port

Hi,

I am using a 2x4HD to integrate two SVS SB3000. MiniDSP suggests using the usb interface for signal to do the subs independent of other speakers or crossovers. REW sees the device via Java interface (MiniDSP is providing the USB drivers). REW allows setting loopback timing.

I did several measurements and get delays = Delay 0.0001 ms (0.03 mm, 0 in) relative to Loopback with no timing offset OR Delay 0.0000 ms (0 mm, 0 in) relative to Loopback with no timing offset.

I can generate Impulse charts.

Most information refers to using acoustical timing in measurement, except in cases with a soundcard. Perhaps the question is = Is the USB IO drivers a suitable soundcard for Java interface of REW?

Thank you,
Greg

Greg
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post #28974 of 29017 Old 03-31-2020, 05:53 PM
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Quote:
Originally Posted by candor View Post
Hi,

I am using a 2x4HD to integrate two SVS SB3000. MiniDSP suggests using the usb interface for signal to do the subs independent of other speakers or crossovers. REW sees the device via Java interface (MiniDSP is providing the USB drivers). REW allows setting loopback timing.

I did several measurements and get delays = Delay 0.0001 ms (0.03 mm, 0 in) relative to Loopback with no timing offset OR Delay 0.0000 ms (0 mm, 0 in) relative to Loopback with no timing offset.

I can generate Impulse charts.

Most information refers to using acoustical timing in measurement, except in cases with a soundcard. Perhaps the question is = Is the USB IO drivers a suitable soundcard for Java interface of REW?

Thank you,
Greg
You spent a lot of time telling how you want to use the USB interface, but you never describe what you are trying to accomplish. You mention “Integrating two SVS SB300’s”. What do you mean by “integrating”? Time-aligning? Finding the flattest response? If we knew what you are trying to accomplish, we could provide some direction.
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post #28975 of 29017 Old 03-31-2020, 06:00 PM
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How do you use the REW alignment tool effectively?

I think I understand how it works, but the displayed alignment, does not match actual measurements. The actual and the align tool differ between 60 and 160 Hz. I do have initial axial room modes at (47.2, 54.4, & 63.2 Hz).

My question is really what way to use the alignment tool to configure the 2x4HD.

I've done things such as align the phase at modal frequencies, potential crossover points, trace crossings. Also tried leveling the phase at places it wasn't.

I get a lot of different delays some 6-9 ms and some 24-26 ms. Sometimes negative delays which I think mean delay the other sub.

What should I be trying?

Thanks for all input and ideas,
Greg
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post #28976 of 29017 Old 03-31-2020, 06:58 PM
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I think I understand how it works, but the displayed alignment, does not match actual measurements. The actual and the align tool differ between 60 and 160 Hz. I do have initial axial room modes at (47.2, 54.4, & 63.2 Hz).

My question is really what way to use the alignment tool to configure the 2x4HD.

I've done things such as align the phase at modal frequencies, potential crossover points, trace crossings. Also tried leveling the phase at places it wasn't.

I get a lot of different delays some 6-9 ms and some 24-26 ms. Sometimes negative delays which I think mean delay the other sub.

What should I be trying?

Thanks for all input and ideas,
Greg
Have you looked at the 2x4 guide linked in my sig? There is a section titled “Checking Sub Alignment using REW Impulse Response Measurement”, starting on page 22, which I think will provide some guidance.
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post #28977 of 29017 Old 04-01-2020, 12:14 PM
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Originally Posted by AustinJerry View Post
You spent a lot of time telling how you want to use the USB interface, but you never describe what you are trying to accomplish. You mention “Integrating two SVS SB300’s”. What do you mean by “integrating”? Time-aligning? Finding the flattest response? If we knew what you are trying to accomplish, we could provide some direction.
I bought the MiniDSP to time align the subs for smoothest FR (at least minimize dips) and improved output (25 - 50 Hz shallow trough and deeper dip(s) that appear at different frequencies depending on what last changed).

If the USB interface is sufficient for time aligning methods, then it seemed the way to go as it eliminates the other components.

Background: For music use a NAD C658 w/Dirac thru 7.1 inputs of Marantz 8001 pre-pro with sub level at -5 dB and speakers at 0 dB. If I try to do a acoustical time reference say using LF and send REW output to RF (disconnected), with xover at 200Hz , I see output on frequencies beyond sub operation which must be crosstalk from RF to LF. This is why I am focused on the USB input of the 2x4HD and loopback timing.

Greg
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post #28978 of 29017 Old 04-01-2020, 12:30 PM
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Quote:
Originally Posted by candor View Post
I bought the MiniDSP to time align the subs for smoothest FR (at least minimize dips) and improved output (25 - 50 Hz shallow trough and deeper dip(s) that appear at different frequencies depending on what last changed).

If the USB interface is sufficient for time aligning methods, then it seemed the way to go as it eliminates the other components.

Background: For music use a NAD C658 w/Dirac thru 7.1 inputs of Marantz 8001 pre-pro with sub level at -5 dB and speakers at 0 dB. If I try to do a acoustical time reference say using LF and send REW output to RF (disconnected), with xover at 200Hz , I see output on frequencies beyond sub operation which must be crosstalk from RF to LF. This is why I am focused on the USB input of the 2x4HD and loopback timing.
Sorry, I have no advice to offer. Your approach is different than anything I have ever tried. Good luck.
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post #28979 of 29017 Old 04-01-2020, 01:28 PM
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I read guide yesterday but have yet to act on it

Quote:
Originally Posted by AustinJerry View Post
Have you looked at the 2x4 guide linked in my sig? There is a section titled “Checking Sub Alignment using REW Impulse Response Measurement”, starting on page 22, which I think will provide some guidance.
I actually read it yesterday before posting last evening. I realized I probably made a mistake in inverting the rear sub from page 22. And starting on page 23, I wondered if impulse charts were valid (is the USB loopback timing accurate or good to use). Except for the fact that step 3 calls for sending signal thru center channel with crossover redirecting it to the sub, I have made these measurements. I think their validity still depends on whether the USB loopback is and adequate timing reference.

I am unclear in step 6 about the alignment. My read is that the start of measurement should align (in example its at 8ms) and I'm guessing the initial peaks should peak at same time. In my impulse chart, the start is same (lookback delay is 0.0 for both measurements), and initial peaks line up. But if this is good alignment, the FR is not good with a chasm between 20-60 Hz (first two attachments). I realize that I didn't run it thru a crossover. I could disconnect both L&R speakers and play signal through both or one of them. Would that be close enough to how you used the center channel? Am I interpreting the impulse correctly?

On the REW alignment tool is appears that choosing different frequencies to either align phase or phase slope and affect the target curve (except for noted inaccuracy in mid bass). If it works that is improvement over trial and error.

I could try to do this with the Marantz but it is the NAD, I am trying maximize the quality.

The third chart is where I ended up via trial and error with rear closer sub inverted and a 6.3 ms delay. The subs are in diagonal corners but facing the opposing side wall. The reason I did that (speaker placement) is no longer valid, so I intend to rotate them to face front and rear before configuring 2x4 again. That would allow a reasonably accurate distance measurement with a laser tool. I was thinking to start there and make .1 ms adjustments if alignment tool isn't useful.

Thank you for producing the guide and helping folks on this and other forums!

Greg
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post #28980 of 29017 Old 04-01-2020, 03:41 PM
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All, need some help. I have an Anthem 1120 receiver connected to my laptop via HDMI but no matter what I do my receiver does not show up in output devices in preferences in REW. Any ideas?
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