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Author Topic: Using Smaart to determine delays on a processor  (Read 14650 times)

Preston Soper

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Re: Using Smaart to determine delays on a processor
« Reply #10 on: November 30, 2011, 10:10:58 pm »

Preston,

Glad you're playing along at home.  Try a 100 Hz low pass instead. ;)  Measure the time arrival of that and a full range signal. (Impluse Response) That's where it started. 

PT

Wow,
Missed that one I thought your previous post was HPF not LPF.
Silly me :)

XTA224
SoundDevices USB Pre
MBP(Boot in 32bit)
V7.3.0.2
Averaging:16
Phase Smoothing: None
Mag Smoothing: None
Weighting: None
FFT: 16k

Here is the example in Transfer mode:
Delay times ranged from 6.60ms to 7.65ms
The trace below is @7.21ms
« Last Edit: November 30, 2011, 11:06:10 pm by Preston Soper »
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Folks, We have reached our cruising altitude now, so I'm going to switch the seatbelt sign off. Feel free to move about as you wish, but please stay inside the plane till we landů It's a bit cold outside, and if you walk on the wing it affects the flight pattern.

Preston Soper

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Re: Using Smaart to determine delays on a processor
« Reply #11 on: November 30, 2011, 10:41:06 pm »

Preston,

Glad you're playing along at home.  Try a 100 Hz low pass instead. ;)  Measure the time arrival of that and a full range signal. (Impluse Response) That's where it started. 

PT

XTA224
SoundDevices USB Pre
MBP(Boot in 32bit)
V7.3.0.2
Averaging:16
Phase Smoothing: None
Mag Smoothing: None
Weighting: None
FFT: 16k
Time Constant: 341ms

Delay Time  7.1 to 7.6 ms
Peak varied with each measurement.

« Last Edit: November 30, 2011, 10:48:28 pm by Preston Soper »
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Folks, We have reached our cruising altitude now, so I'm going to switch the seatbelt sign off. Feel free to move about as you wish, but please stay inside the plane till we landů It's a bit cold outside, and if you walk on the wing it affects the flight pattern.

Paul Tucci

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Re: Using Smaart to determine delays on a processor
« Reply #12 on: December 01, 2011, 08:37:41 am »

and the full range measurement??
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Preston Soper

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Re: Using Smaart to determine delays on a processor
« Reply #13 on: December 01, 2011, 09:22:42 am »

and the full range measurement??

XTA224
SoundDevices USB Pre
MBP(Boot in 32bit)
V7.3.0.2
Averaging:16
Phase Smoothing: None
Mag Smoothing: None
Weighting: None
FFT: 16k
Time Constant: 341ms

10Hz-LR-24db - 22K-LR-24db
Delay @ Peak 2.2ms

« Last Edit: December 01, 2011, 09:26:05 am by Preston Soper »
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Folks, We have reached our cruising altitude now, so I'm going to switch the seatbelt sign off. Feel free to move about as you wish, but please stay inside the plane till we landů It's a bit cold outside, and if you walk on the wing it affects the flight pattern.

Paul Tucci

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Re: Using Smaart to determine delays on a processor
« Reply #14 on: December 01, 2011, 11:05:31 am »

The point being that the same DSP exhibited different latency as measured by the Impulse Response of Smaart.
The full range signal showed a latency of 2.2 mSec, the low passed signal showed a latency of 7+ mSec.

How can that be?


...and so it all began...

PT
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Martyn ferrit Rowe

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Re: Using Smaart to determine delays on a processor
« Reply #15 on: December 01, 2011, 12:18:57 pm »

And when you shared this with me a long time ago a small fire started............. 8)

ferrit
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Doug Fowler

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Re: Using Smaart to determine delays on a processor
« Reply #16 on: December 01, 2011, 12:29:51 pm »

The point being that the same DSP exhibited different latency as measured by the Impulse Response of Smaart.
The full range signal showed a latency of 2.2 mSec, the low passed signal showed a latency of 7+ mSec.

How can that be?


...and so it all began...

PT

I use "auto delay" in ST class and sweep a low pass filter to demonstrate the effect.  It tends to get the uninitiated thinking in a different direction.
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"It's got electrolytes.  It's got what plants crave."

Jay Barracato

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Re: Using Smaart to determine delays on a processor
« Reply #17 on: December 02, 2011, 05:46:38 pm »

The point being that the same DSP exhibited different latency as measured by the Impulse Response of Smaart.
The full range signal showed a latency of 2.2 mSec, the low passed signal showed a latency of 7+ mSec.

How can that be?


...and so it all began...

PT

So are you going to leave us guessing?

At 100hz my sabine navigator goes to 3.05 ms from 1.50 ms for the full range signal using the delay finder. It is a difference of 1.1 ms using the IR.

My best guess is that it is a function of the wavelength and the fact that the longer wavelengths vibrate slower.
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Jay Barracato

Mac Kerr

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Re: Using Smaart to determine delays on a processor
« Reply #18 on: December 02, 2011, 06:34:28 pm »

So are you going to leave us guessing?

It's probably just a phase he's going through.

Mac
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ProSoundWeb Community

Re: Using Smaart to determine delays on a processor
┬ź Reply #18 on: December 02, 2011, 06:34:28 pm ┬╗


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