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Room EQ Wizard Import Sweep

MRC01

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I've used REW for a while now, taking measurements, importing sweeps, no problems. I just ran into one that I can't figure out.
Using version 5.20 Beta 4, I generated frequency sweep files. Played them back while recording.
Then I go back to REW (same 5.20 Beta 4) and import the sweep recording. REW gives me this error:
1568338931198.png

Problem is, the error message is incorrect. This sweep file was indeed generated from the very same version of REW into which I'm importing it! And the purple chart shows that REW did indeed read the sweep file.
So, REW must be looking for something in this audio file that it's not finding. What could that be? You can see the sync pulse is also there just before the sweep.
I've done this lots of times and never seen this before.
 

Blumlein 88

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I had that happen a few versions back. Only one of my computers had the error. I rolled back to the prior version of REW on that machine. When the next update happened everything worked fine.

So may or may not be your problem. I'd probably just go back one step and wait for 5.21 to come out.
 
OP
MRC01

MRC01

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Ah I just figured it out. It's a 2 step process and I forgot the first step. Step 1: load the stimulus (original WAV generated by REW). Step 2: load the response (WAV that was recorded). I forgot step 1.
Brain fart, nothing to see here, move along...
 

Blumlein 88

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Ah I just figured it out. It's a 2 step process and I forgot the first step. Step 1: load the stimulus (original WAV generated by REW). Step 2: load the response (WAV that was recorded). I forgot step 1.
Brain fart, nothing to see here, move along...
Don't feel bad. I need the updated version of REW that automatically fixes brain farts.
 

SplitTime

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I know this is an old post - but I was poking around as I was trying to figure out how to do something perhaps similar. I can easily make direct measurements with REW driving the source and the mic. But I am exploring the use of digital filters in JRiver - and I'd like to confirm the measurements with REW afterwards. Seems perhaps I'm doing things slightly differently than the original AP, but thought I'd post for others to comment if I'm off in the weeds (or not).

1. From REW I used the "generator" to create a .wav file of the measurement sweep - including the acoustic timing reference. Did this twice, once for each of the L & R speakers. (Just trying stereo for now.)
2. Now I open JRiver and load either the L or R .wav file, apply filters, ...
3. Play the sweep from JRiver and make sure the levels are good in REW - well above the noise floor, but not clipping or too loud.
3. Turn down the volume, from it's present setting, on my pre-amp by -20dB to -30dB
4. Back on the REW screen I go to measurement - just as if I'm going to make a measurement from REW. Set the source for either L or R - depending on which .wav file I'm planning to play from JRiver. However I turn down the output to -60dB (won't go any lower) for both the tone and the acoustic timing reference.
5. In REW start the measurement... the lower pre-amp volume avoids the problem I was having that even at -60dB (inside REW) my mic was still picking up the REW acoustic timing reference and starting to measure before I started the JRiver .wav file. Now, with the pre-amp volume reduced when REW outputs the accosting timing reference, the REW listening to the mic doesn't hear it.
6. So now I wait a few seconds (after the acoustic reference is played by REW) and then turn the volume on my pre-amplifer back up. I can faintly hear the end of the sweep from REW, and wait for the output level in the REW window to stop.
7. In JRiver play the .wav file. Now I get a full volume acoustic timing reference (which trigger's REW's measurement) and full volume sweep.
8. The resulting measurement is in REW just as if I'd made the full measurement in REW itself. But I can see the results of the filters having been applied through JRiver.

Everything is connected to a single laptop. Running REW and JRiver at the same time.

Perhaps this was obvious to everyone else - or perhaps I'm missing something and there is some disadvantage to this method? I see people saying that they make measurements through JRiver (others) but it always seems like there is a different measurement step. Anyway, please let me know if I'm off in the weeds. If not, then this will help someone else. Merry Christmas!
 

SplitTime

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why not just output from rew directly via jriver?
If there is a method to redirect REW’s output from default (HDMI or USB) to JRiver‘s input (presumably as some sort of streaming input connection) which can then be processed by JRiver filters before proceeding to the (HDMI or USB) output, I don’t know what the mechanisms are to do it. I’m open to instructions on how to do it though. ;)

EDIT: since I’m running REW & JRiver on the same laptop - the connection would need to be SW not HW.
 
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