Beta Test: Multitone Loopback Analyzer software

[audio_tony]

Please try the latest official version. This displays harmonics as %:

Thank you.

I have also sent you a DM.

 

[Matcs]

Idea: Develop a routine for conducting a Sweep Jitter vs Frequency test for analysing a CD player. This involves generating test tones with embedded tonal codes at the beginning that allow MA to recognize the remote procedure, exporting these tones, and burning them onto a CD for testing.

BTW, thank you for the development of Multitone Analyser!

 

[Sokel]

I "think" there's something wrong with IR chart.

(truth is I used some un-natural signals, so could very well be me )

 

[pkane]

I "think" there's something wrong with IR chart.

(truth is I used some un-natural signals, so could very well be me )

Probably not you It seems I forgot to remove some experimental code that screwed up the IR plot.

Please reinstall (uninstall previous version): https://app.box.com/s/ue7ll9xmvwogst817x2l1xg09opvgy47

The website/download version has also been updated to this latest.

 

[Sokel]

Probably not you It seems I forgot to remove some experimental code that screwed up the IR plot.

Please reinstall (uninstall previous version): https://app.box.com/s/ue7ll9xmvwogst817x2l1xg09opvgy47

The website/download version has also been updated to this latest.

View attachment 469884

Now perfect!

 

[Sokel]

Let's see if it's me now or a glitch.

At any rate I/O everything is ok unless I play 352.8kHz and capture at 44.1kHz.
The chart seems ok, the results though...

Nor the noise neither the distortion is up there but THD+N says -44.9dBr.

(that's 20Hz sine there, at 1kHz is ok))

 

[pkane]

Let's see if it's me now or a glitch.

At any rate I/O everything is ok unless I play 352.8kHz and capture at 44.1kHz.
The chart seems ok, the results though...



View attachment 472858

Nor the noise neither the distortion is up there but THD+N says -44.9dBr.

(that's 20Hz sine there, at 1kHz is ok))

Make sure to include the fundamental frequency in the measurement bandwidth. Your 20Hz lower bound excludes it. Try setting lower frequency to between 5 and 10Hz.

 

[Sokel]

Make sure to include the fundamental frequency in the measurement bandwidth. Your 20Hz lower bound excludes it. Try setting lower frequency to between 5 and 10Hz.

I thought about it and played around.

What seems to matter most is not the lower limit but FFT size and captured rate.

For example, same test with 96kHz/352.8kHz I/O:

All results, noise, distortion, etc are about the same but the calculation is very different.
I have seen that in general when measuring very low, FFT size matters a lot, despite I/O rates.

The same chart gives about 10dB worst THD+N if I set FFT size at 512k.

The joys of measuring!

 

[pkane]

Love the sound of DSD quantization noise in the morning! This is a 1024x48k file - @49.152MHz sampling rate, measured by MTA:

 

[Sokel]

Love the sound of DSD quantization noise in the morning! This is a 1024x48k file - @49.152MHz sampling rate, measured by MTA:

View attachment 476344

View attachment 476346

kHz is for the faint at heart

(I can't even play 48k family, no DAC that I have plays it )

 

[pkane]

kHz is for the faint at heart

(I can't even play 48k family, no DAC that I have plays it )

Oh, you're missing so much!(noise, that is!)

 

[pkane]

It's been a while, so I thought I'll release a new version of Multitone, v1.2.18. It's a preview for now, to become the next official version as soon as there are no more bugs found/reported:

https://app.box.com/s/ue7ll9xmvwogst817x2l1xg09opvgy47

(Apologies in advance to all who are offended by any mention of DSD )

The changes in this version are mostly around DSD, with a minor addition to the test signal specification:

• Added support to save test signals in DSF (DSD) file format, up to DSD1024
• Added support for reading and displaying spectrum for DSF (DSD) files if dropped into the spectrum window
• Added option to play and generate DSD test signals with bandwidth not limited by the DSD base rate (Test Signal/DSD Gen multiplier setting)
• Added a 7th order DSD modulator option (previously 6 was the maximum)
• Added arbitrary low-pass and high-pass filter option to the test signal specification

Test signals can now be generated and saved in DSF format:

Note that DSD files can be large, pay attention to the estimated file size. Also, processing native 1-bit DSD at large sample rates can take a while. Be patient, especially on laptop or with underpowered CPUs!

Files can be generated with base rate of 44.1k or 48k, and mono or stereo.

Dropping a DSF file into the spectrum plot will generate a full spectrum (using selected FFT size and averaging). DSD files can be large, so MTA will limit the number of samples loaded and analyzed to about 20 million. Note that this process doesn't convert DSD to PCM -- the analysis is done at the original DSD sampling rate with 1 bit samples:

For test signals that have frequencies above (or below) the desired test range, test signals now can include a low-pass or high-pass filter specification. The filter used is a first-order Biquad. To specify a low-pass filter include LP=freq on the test signal specification. For high-pass, HP=freq:

For example, TIM(Curl) sq:3.18k/15k 4:1 LP=100k will generate the desired test signal and then low-pass filter it at 100kHz.

 

[Sokel]

Oh, boi!
Tomorrow will be a long day!

Thank you!

 

[morillon]

A little Sigma2 in w&f mode?? ;-))

 

[pkane]

A little Sigma2 in w&f mode?? ;-))

Not yet

 

[Sokel]

Ok now.
Nothing broken I have found but it feels a little unresponsive compared to the previous version?
A little rough?

At FR measurements with log chirps for example at some times it takes two times to get there.
Or the progression of averages, it's not smooth but that feels more a PC power problem although not there before, so much, but reasonable at my prehistoric 10 yo PC.
All the above with both PCM and DSD and modest FFT, nothing extreme 256k or so.

(DSD stuff is a killer! )

 

[Rantapossu]

This is my 1 kHz sine with V1.2.18. The test signal is about 4 seconds too short. It messes up the measurement:

With V1.2.15 everything is ok:

Here are both recordings from the history folder:

 

[Sokel]

This is my 1 kHz sine with V1.2.18. The test signal is about 4 seconds too short. It messes up the measurement:

View attachment 488611


With V1.2.15 everything is ok:

View attachment 488612


Here are both recordings from the history folder:

View attachment 488613

I does seem to do the first couple of averages odd for me as well, specially at DSD.

 

[pkane]

This is my 1 kHz sine with V1.2.18. The test signal is about 4 seconds too short. It messes up the measurement:

View attachment 488611


With V1.2.15 everything is ok:

View attachment 488612


Here are both recordings from the history folder:

View attachment 488613

Hmm, have to take a look at this, I did try to speed up and shorten the measurement cycle. Maybe I overdid it

 

[Rantapossu]

Hmm, have to take a look at this, I did try to speed up and shorten the measurement cycle. Maybe I overdid it

I found it. It is the Warm-up time!

If I reduce it from my normal 3 seconds to 0 seconds, everything works ok. If I change it to 10 seconds, the test tone will be 11 seconds too short.