Help! REW Problem with sweeps

[Fernando]

Hello.
When I do a measure there is no problem, but when I do 2 or 4 sweeps some falls appear that I can't understand.
Why is it, I have something wrong configured?

 

[Fernando]

Help me! @JohnPM

 

[JoachimStrobel]

Amp/Speaker fatigue?

 

[Jdunk54nl]

How did you take all of this data? You need to be more specific. Did you move the mic between the sweeps when multiple? Was it always in the same spot? Same speaker? Etc.

 

[Fernando]

How did you take all of this data? You need to be more specific. Did you move the mic between the sweeps when multiple? Was it always in the same spot? Same speaker? Etc.

Sure! all in the same conditions of volume, position, etc ... only change of number of sweeps.

 

[Jdunk54nl]

Sure! all in the same conditions of volume, position, etc ... only change of number of sweeps.

Are the sweeps averaged for that data? If so how did you average them?

 

[Fernando]

Are the sweeps averaged for that data?

I do not understand the question.

 

[Jdunk54nl]

What did you do to get the 2 sweeps and 4 sweeps as a single line? My gut reaction right now is comb filtering at the higher frequencies.

 

[Fernando]

What did you do to get the 2 sweeps and 4 sweeps as a single line? My gut reaction right now is comb filtering at the higher frequencies.

REW sweeps and averages. Do you use REW?

I'll try the Sweep Delay, in case it's the cause, but I don't think so.

 

[Jdunk54nl]

I've used REW quite a bit.

So is this what you did? (again these details on your exact stuff is important to help diagnose anything over the internet. Screenshots of settings really help)
Clicked on measure, set repetitions to 2 or 4 then measured?

 

[Fernando]

Notice to navigators.

 

[Fernando]

...
Clicked on measure, set repetitions to 2 or 4 then measured?

Yes.

 

[daftcombo]

In my opinion this is a REW bug.
I've had such weird behaviour and reported to John in the past.

 

[Fernando]

Notice to navigators.
View attachment 128889

This is weird, I've been doing this for a long time and never had a problem. Smells like bug.

 

[daftcombo]

Multiple sweeps are useless IME anyway.
Stick to single 256k.