abbey road d enfer

Digilent Analog Discovery 2
« on: September 05, 2017, 12:20:35 AM »
Hi all,
Just been aware of this product
https://analogdiscovery.com/
Anyone have tried it? Indeed it would need a proper interface for audio use, but it seems that the software would be adequate...
Who's right or wrong is irrelevant. What matters is what's right or wrong.
"The important thing is not to convince, but to give pause for thought." (B. Werber)
Star ground is for electricians.


ruairioflaherty

Re: Digilent Analog Discovery 2
« Reply #1 on: September 05, 2017, 03:13:59 AM »
There's been lots of talk over at the EEVBlog forum over the years, almost all very positive,

I've been tempted but I can't justify it, I have separate hardware pieces that cover all of the functions bar the bode plot above 96k (where my dScope tops out),


ruairioflaherty

Re: Digilent Analog Discovery 2
« Reply #2 on: September 05, 2017, 03:24:31 AM »
If the goal is audio analysis check out the ongoing projects by Jan Didden (of Linear Audio) and Frex over at DIYaudio.  Didden is working on an auto rangers for use in front of standard audio interfaces to improve performance and emulate the wider input capabilities of AP/dScope/R&S, keeping signals in the sweet spot of the AD converter.

https://linearaudio.nl/la-autoranger

http://www.diyaudio.com/forums/equipment-and-tools/310334-at2380v1-2-channels-digitally-controlled-stepped-attenuator.html


ruffrecords

Re: Digilent Analog Discovery 2
« Reply #3 on: September 05, 2017, 04:13:10 AM »
I like the way they say it costs the same as a text book. $279 for a text book??

All the same, looks like it could be useful.

Cheers

Ian

abbey road d enfer

Re: Digilent Analog Discovery 2
« Reply #4 on: September 05, 2017, 04:33:43 AM »
If the goal is audio analysis check out the ongoing projects by Jan Didden (of Linear Audio) and Frex over at DIYaudio.  Didden is working on an auto rangers for use in front of standard audio interfaces to improve performance and emulate the wider input capabilities of AP/dScope/R&S, keeping signals in the sweet spot of the AD converter.

https://linearaudio.nl/la-autoranger

http://www.diyaudio.com/forums/equipment-and-tools/310334-at2380v1-2-channels-digitally-controlled-stepped-attenuator.html
These are interesting projects, but I already have built my own interface, originally for the QA400 that is now collecting dust on a shelf. I intended to use it with a standard USB soundcard and RMAA or similar software, but it looks like this Analog Discovery would be a nice alternative.
Who's right or wrong is irrelevant. What matters is what's right or wrong.
"The important thing is not to convince, but to give pause for thought." (B. Werber)
Star ground is for electricians.

ruairioflaherty

Re: Digilent Analog Discovery 2
« Reply #5 on: September 05, 2017, 11:22:56 AM »
I like the way they say it costs the same as a text book. $279 for a text book??

I have yet to experience it but by all accounts college textbooks here in the U.S. are extraordinarily expensive.  I hope to go back in the next few years so I'm sure I'll know all about it soon…



ruffrecords

Re: Digilent Analog Discovery 2
« Reply #6 on: September 05, 2017, 11:35:28 AM »
Is Digilent in any way related to Agilent?

Cheers

Ian

ruairioflaherty

Re: Digilent Analog Discovery 2
« Reply #7 on: September 05, 2017, 11:40:06 AM »
These are interesting projects, but I already have built my own interface, originally for the QA400 that is now collecting dust on a shelf. I intended to use it with a standard USB soundcard and RMAA or similar software, but it looks like this Analog Discovery would be a nice alternative.

Sorry to hear that the QA400 didn't work out.

There was an interesting third party project in the works for the AD2 but the developer has disappeared for the last while - https://www.eevblog.com/forum/projects/analog-disovery-as-audio-analyzer/

I think residual THD+N was somewhere around 0.01% so not good for any development serious work but useful nonetheless.

His impedance analyzer project was even more interesting to me so I'm hoping that he resurfaces.

The AD2 seems to be gaining traction fast as the standard tool in the hobby electronics/maker/student space.

ruairioflaherty

Re: Digilent Analog Discovery 2
« Reply #8 on: September 05, 2017, 11:43:09 AM »
Is Digilent in any way related to Agilent?

Cheers

Ian

No relation. Digilent is now owned by National Instruments.

Agilent spun off their Test & Measurement division as Keysight a few years back. 


gyraf

Re: Digilent Analog Discovery 2
« Reply #9 on: September 06, 2017, 03:26:14 AM »
I've been looking at Red Pitaya lately - https://redpitaya.com/ - not entirely aimed at audio, but with some pretty interesting possibilities (and open source too)

Jakob E.
..note to self: don't let Harman run your company..


Re: Digilent Analog Discovery 2
« Reply #10 on: September 06, 2017, 11:34:42 AM »
I've been looking at Red Pitaya lately - https://redpitaya.com/
Interesting. Specs are up there and it's inexpensive. Much less expensive than a QA401.

But my experience has been that the software is what makes or breaks these things. The QA400 software is actually pretty good. The Red Pitaya software is actually just running in a Web browser which immediately makes me think it could be "simple".

abbey road d enfer

Re: Digilent Analog Discovery 2
« Reply #11 on: September 06, 2017, 02:08:34 PM »
But my experience has been that the software is what makes or breaks these things. The QA400 software is actually pretty good.
As I mentioned earlier, my QA400 is now gathering dust on a shelf. The main reason was the very limited software and the difficulty to create new sxcriprts. Do you imply this has changed? It's a long time since I last checked...
Who's right or wrong is irrelevant. What matters is what's right or wrong.
"The important thing is not to convince, but to give pause for thought." (B. Werber)
Star ground is for electricians.

Re: Digilent Analog Discovery 2
« Reply #12 on: September 06, 2017, 02:46:05 PM »
As I mentioned earlier, my QA400 is now gathering dust on a shelf. The main reason was the very limited software and the difficulty to create new sxcriprts. Do you imply this has changed? It's a long time since I last checked...
No. I didn't even know you could script it. If you think it's limited then I would be interested in knowing what analyzer has software that you consider to be good. Certainly anything using an external sound card cannot possibly complete with something that uses a correlated impulse response type measurement like the QA400 does. Are you talking about an Audio Precision system or something like that?

abbey road d enfer

Re: Digilent Analog Discovery 2
« Reply #13 on: September 06, 2017, 06:08:14 PM »
No. I didn't even know you could script it. If you think it's limited then I would be interested in knowing what analyzer has software that you consider to be good. Certainly anything using an external sound card cannot possibly complete with something that uses a correlated impulse response type measurement like the QA400 does. Are you talking about an Audio Precision system or something like that?
You are talking of metrology; impulse-based measurements have their advantages, and their pitfalls too. I was talking about the housekeeping software. My request was simple, I wanted to do amplitude sweeps; the answer from QA was that I should write the script, for which they gave no examples and very vague guidelines. I'm not a programmer, so I gave it to my assistant, who's very good at it, and she couldn't do it. Also, the QA400 does not allow graph overlay, which is an absolute necessity when doing final adjustments.
Who's right or wrong is irrelevant. What matters is what's right or wrong.
"The important thing is not to convince, but to give pause for thought." (B. Werber)
Star ground is for electricians.

Re: Digilent Analog Discovery 2
« Reply #14 on: September 06, 2017, 06:49:41 PM »
My request was simple, I wanted to do amplitude sweeps; the answer from QA was that I should write the script, for which they gave no examples and very vague guidelines. I'm not a programmer, so I gave it to my assistant, who's very good at it, and she couldn't do it. Also, the QA400 does not allow graph overlay, which is an absolute necessity when doing final adjustments.
I don't recall the details but it can do a stepped sweep. They did do a significant software update at some point. What I like to do is set Averaging to 8 and let it run for ~10 seconds and then I hit the space bar to pause. Then I take a screen shot and use whatever image viewer key mnemonic to switch between screenshots and thus compare the two plots. Or you if you really want an "overlay" you could export the data and plot both results in Excel.

The QA400 software is far from perfect. It is a little "simple" itself and it's not terribly accurate. But it is precise enough for comparative analysis.

abbey road d enfer

Re: Digilent Analog Discovery 2
« Reply #15 on: September 06, 2017, 06:56:17 PM »
I don't recall the details but it can do a stepped sweep.
Stepped sweep is a frequency sweep, what I want is amplitude sweep to test compressors/gates.

Quote
Then I take a screen shot and use whatever image viewer key mnemonic to switch between screenshots and thus compare the two plots. Or you if you really want an "overlay" you could export the data and plot both results in Excel.
These are pathetic workarounds IMO. Several freewares do overlay.
Who's right or wrong is irrelevant. What matters is what's right or wrong.
"The important thing is not to convince, but to give pause for thought." (B. Werber)
Star ground is for electricians.

Re: Digilent Analog Discovery 2
« Reply #16 on: September 06, 2017, 10:52:41 PM »
Stepped sweep is a frequency sweep, what I want is amplitude sweep to test compressors/gates.
There is a macro called THD vs Output Level. Not quite the same but I actually used it to test an 1176 and described it here:

QA400 analysis of 1176 ratios

abbey road d enfer

Re: Digilent Analog Discovery 2
« Reply #17 on: September 07, 2017, 02:17:18 AM »
There is a macro called THD vs Output Level.
Yes, I am aware of it; typically used for testing power amps. It's not what I want. These people at QA are good developers but they don't understand the needs of audio pro. I believe it would take them a few minutes to adapt this macro to level measurement, but they seem to be too busy to even consider.
Who's right or wrong is irrelevant. What matters is what's right or wrong.
"The important thing is not to convince, but to give pause for thought." (B. Werber)
Star ground is for electricians.