DeltaWave null-testing audio comparator (beta)

[Jud]

5 hours ago, pkane2001 said:

 

Just realized that some of the ringing is due to FIR filters being used in DW. Audacity, for example, uses IIR filters, such as Butterworth, which produce no ringing in the transition band, but do affect phase in non-linear ways.

 

So, it's a tradeoff: a filter that causes ringing or one that introduces phase distortions. I may have to add the choice of both in settings. Let me think about it. 

 

I have no idea how possible this is, but could you add the capability to use a filter of choice?  Might allow people to see the effect of different filter settings in SoX, for example.

[Jud]

3 hours ago, esldude said:

Third piece of music.  First a loopback measure on the Zen Tour interface, and then a separate DAC feeding the ZT ADC.  A pattern consistent across conditions with this piece of music.  But a third pattern with the third piece of music.  These two are not quite identical, but almost. 

 

 

Or - oh dear! 👹 - the clocking done with the recording somehow comes through in the results! 😳

[Jud]

6 hours ago, esldude said:

 

I don't think it is clocking actually because previously I've changed clocks and three of them give the same pattern on one of my ADCs. 

 

My original remark was more than a little tongue in cheek (thus the emojis). But as long as you feel like exploring this a little, could you do it with some recordings you have made from "live" sources with different ADCs, to see whether characteristic patterns per ADC emerge? (Yes I realize there should be no distinction between a recording of a live source and any other analog source.)

[Jud]

3 hours ago, TomCapraro said:

ah ... I forgot to say that the software immediately realizes the quality change of the DAC because I also redid a loopback with a better dac and the null test (between original and recorded signal) produces a cancellation much more evident.

 

That’s a quite interesting application - which DACs produce the most consistent results and lowest noise.

 

Edit: Hmm, and under which environmental (e.g., electrical) conditions....

[Jud]

2 hours ago, TomCapraro said:

The electrical conditions appear to be under the same clock, with the same cables, and with the same ADC that recorded them.

 

Yes, I was thinking it would be interesting to experiment with changes to cables, various electrical noise reduction strategies (using or not using particular power supplies, for example), and see whether anything at all came of it.

[Jud]

5 minutes ago, pkane2001 said:

 

Pretty much so, Dennis. There were many internal computation changes in this last version. Once I address any issues reported in it, I’m ready to call the end to the beta test

 

 

Apologies for not having followed this particular point, but does the software have the capability now of using either channel as the "original"?  To me it may give one channel a slight advantage in simultaneous comparisons if it is always the template to which the selection on the other channel is adjusted.  (Sorry if I'm not expressing this well. It's the first time I've thought about it in a while and I don't recall all the details.)