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Beta Test: Multitone Loopback Analyzer software

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pkane

pkane

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Ok I have one but it's maybe me or the function of the sample rate.
(I measured a nice analog thing)

That's 44100 going smoothly:



View attachment 232122


...but have is going on with 96000 sample rate down there???


View attachment 232123

(repeatable)

That seems like it's really performing like that. Just do a single spectrum capture at 0dBFS and 5Hz and look to see what's going on there.
 

Sokel

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That seems like it's really performing like that. Just do a single spectrum capture at 0dBFS and 5Hz and look to see what's going on there.
Figured it out myself,it's the notch filter.

without.PNG


without


with.PNG


with.

And a second (question)
Is ther a way to superimpose sweeps?
 

Blumlein 88

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@pkane
Maybe you could take a look at the 2nd page on this thread.

About measuring very low frequencies. Perhaps you know why measurements around and below 10 hz seem to fluctuate and give lower readings than expected.

Oops, just as I posted I see you commented in that thread.
 
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pkane

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@pkane
Maybe you could take a look at the 2nd page on this thread.

About measuring very low frequencies. Perhaps you know why measurements around and below 10 hz seem to fluctuate and give lower readings than expected.
Just responded.
 
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pkane

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Updated v1.0.49 is available: https://app.box.com/s/qbrh3czrvudclkqs9n8lm806k3hzmjx5

A couple of changes:
  • Fix for a crash when a multitone test is selected with a very narrow range (31-63Hz, for example) as well as a crash when 0Hz selected as starting multitone frequency
  • Change to use longer intervals when computing the value for the level meter to accommodate the lowest frequency in the test signal
 

Blumlein 88

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Updated v1.0.49 is available: https://app.box.com/s/qbrh3czrvudclkqs9n8lm806k3hzmjx5

A couple of changes:
  • Fix for a crash when a multitone test is selected with a very narrow range (31-63Hz, for example) as well as a crash when 0Hz selected as starting multitone frequency
  • Change to use longer intervals when computing the value for the level meter to accommodate the lowest frequency in the test signal
Dang I was about to report the two crash situations. You have already fixed them it sounds like. :)
 

Blumlein 88

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Still doesn't work starting a sweep from 0,Not like before,now it goes on to the next ones but they end up showing nothing.
I had the same thing. It appears to be working, but ends up with empty display.
 

Sokel

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What is funny is that E-mu blocks 0Hz so hard that is better than silence:

Orange=silence
blue=0Hz

0Hz.PNG
 

Blumlein 88

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The meter fluctuates over as wide a range of level as before just does so more slowly.
 
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pkane

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The meter fluctuates over as wide a range of level as before just does so more slowly.

Don't know... Seems stable here, even at 3Hz. Fluctuations of maybe +/- 0.1dB over a long period. Previously, the update interval was 200ms which is good for down to 5Hz or so but would fluctuate more wildly below. Now MT will auto-adjust to longer update intervals if the lowest frequency is below 5Hz to make sure an entire cycle is included.

3.png
 
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pkane

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Sokel

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And another,after 0hz where says 1/21 jumps at 2Hz saying 4/21 without 2/21 and 3/21.
 
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