New REW Problem

[SimpleTheater]

I've never had this issue with REW before - almost nothing in measurements above 6kHz. I've played an 11kHz tone and it comes through REW without a problem.

The only difference between these measurements and past is that I'm using a headphone to RCA cable on my laptop - past times I used HDMI. But like I said, REW plays the high pitched tones via the generator without a problem. My UMIK mic, using the SPL, registers 50 db increases when I play a 10, 11 or 12 kHz tone.

Any idea why my measurements look like this?

 

[boxerfan88]

Maybe some settings causing it...if you don't mind losing the preferences, just go Preferences > Delete preferences and shutdown.
Restart app and reconfigure and retry measurement...

 

[SimpleTheater]

Thanks boxerfan88. I updated REW with the latest version and got a ton of static and noise in my generator. I then went to device manager and disabled RealTek, then re-enabled it, and voila - 20-20khz is now working.

 

[SimpleTheater]

Seems like my trick worked once, but not again. What I'm doing now, to make sure the mic is working, is I'm sending a 10,000 hz tone through another speaker when testing the other one. You can see on the graph, the UMIK is picking up that tone (purple is with the 10kHz.

The issue appears to be that the REW generator isn't sending out tones above 6 kHz. Is there a way of checking that?

test tone in background)

 

[boxerfan88]

You may want to check|enable "Allow applications to take exclusive control of this device" for the Realtek/output device.

This will allow REW to take exclusive control of the device, and prevent Windows from operating the device in shared mode, which can be messy.

 

[SimpleTheater]

Weirdest thing. If I change the frequency in measurements to above 200 hz, I get values to 20,000. See attached. But 20 - 20k, it goes back to losing everything above 6k.
Green plot is 20-20k
Red is 5k - 20 k
Blue is 10k-20k

 

[SimpleTheater]

Hopefully the last image. You can see on the far left which plot color starts at what frequency. 20-20k drops off around 6khz, 100-20khz seems to get close to 13khz, etc.

 

[SimpleTheater]

This guy had the same problem

REW problem. High frequencies are cut no mather what I do

Hi. I have problem with REW, but only on laptops. I want basic 20-20Khz sweep. So I set it up, run it, I clearly hear it going to the high frequencies. Then I look at results and for some reason one laptop rolls off everything over 6Khz (lets call it i7), and very old laptop rolls of at 7khz...

www.diyaudio.com

Something about Loopback - anyone know how to check this on a Windows 10 machine?

 

[sejarzo]

Most raw unsmoothed measurements of speakers in rooms show a lot more variation in SPL above 10k than the +/- 2 or 3 dB your plots show. (EDIT: I misread the scale on the SPL axis.)

Have you listened to the sweep on headphones to be sure that your soundcard output is correct?

 

[staticV3]

@SimpleTheater what audio API are you using in REW? Java, Java EXCL, or ASIO?

 

[sejarzo]

This guy had the same problem

REW problem. High frequencies are cut no mather what I do

Hi. I have problem with REW, but only on laptops. I want basic 20-20Khz sweep. So I set it up, run it, I clearly hear it going to the high frequencies. Then I look at results and for some reason one laptop rolls off everything over 6Khz (lets call it i7), and very old laptop rolls of at 7khz...

www.diyaudio.com

Something about Loopback - anyone know how to check this on a Windows 10 machine?

It appears he had the same problem, but he was using the mic input of his laptop's internal sound card to record the response of the measurement mic, not a USB mic like the UMIK that essentially is a measurement mic plus USB sound card in one device.

A loopback uses a cable between sound card output and input to be sure that it's working OK. No way to do a loopback with the UMIK, nor any need for it, as it's irrelevant.

 

[JohnPM]

Looks like the end of the sweep capture is being truncated, likely due to latency in the replay chain. Use the acoustic timing reference option.

 

[JohnPM]

he was using the mic input of his laptop's internal sound card

Laptop mic inputs sometimes default to 16 kHz sampling.

 

[SimpleTheater]

@SimpleTheater what audio API are you using in REW? Java, Java EXCL, or ASIO?

Java

 

[SimpleTheater]

Looks like the end of the sweep capture is being truncated, likely due to latency in the replay chain. Use the acoustic timing reference option.

I'll try that when I get back tonight and let you know how it goes. Thanks.

 

[staticV3]

Java

Try EXCL. That'll prevent Windows APOs messing with your results.
Also try a USB DAC instead of the integrated output. Just an Apple dongle is enough.

 

[SimpleTheater]

Looks like the end of the sweep capture is being truncated, likely due to latency in the replay chain. Use the acoustic timing reference option.

Unfortunately the only place I can find timing reference is here. Nothing about time adjustment, just left/right.

 

[NTK]

I think John was referring to this option.

 

[SimpleTheater]

Looks like the end of the sweep capture is being truncated, likely due to latency in the replay chain. Use the acoustic timing reference option.

Found it. I just assumed it was somewhere in preferences, not the measurement window.

 

[SimpleTheater]

Can't thank everyone enough who helped out on this. Timing reference, set to "Use acoustic timing reference" worked.