rackmonkey

Re: Digilent Analog Discovery 2
« Reply #20 on: August 26, 2019, 10:42:32 PM »
I found the freeware add-on not-so-useful. I think the project predated the AD2 and was written to address some shortcomings in the original AD software.  First, all of the functionality in the add-on is already there in the newer Waveforms software. More importantly, the tools in the add-on are less functional than what’s in the current Waveforms suite. Lack of flexibility - such as the inability to change window types (e.g., Blackman-Harris, Rectangular, Hanning, etc) and the lack of a smoothing function (which makes it impossible to actually see not-so-subtle differences between test results) - really hamper the tool and make it far less useful than REW or any software tools we commonly use.

In short, don’t bother.

That said, the AD2 itself is a great little tool, as is the newest Waveforms software. The bandwidth alone makes it worth having alongside  a soundcard+REW type setup. You can see things no average soundcard will see, such as high frequency ringing when evaluating zobel network part values. But I still would ‘t want it as my only testing tool. I find myself still going to REW for a lot of common tests.

Best features of AD2/Waveforms for audio testing:

- Add on impedance analyzer breakout board from Digilent. Quick and easy input/output impedance tests
- Curve tracer add-on board from Knack Supply is convenient for what it does
- Bandwidth far beyond soundcard capabilities
- Breadboard adapter addon board is handy for obvious reasons
- Logging/scripting capabilities
- Logic analyzer for digital work
- Of course, having a scope, FFT, two channel function generator and curve tracer (and more) windows to tile or toggle between for tests is great. Can’t do that with a soundcard + audio test sw.

Biggest knocks on AD2+Waveforms SW are that you don’t have the number of window functions you get with audio test sw (just Hanning and Blackman if I recall, correctly, but don’t quote me on that. Might have been BH and rectangular), and there’s no smoothing function. {EDIT: To be clear, I’m talking about the Digilent Waveforms software that comes with the AD2 here, not the freeware add-on I talk about above. It DOES support changing window functions (unlike the freeware) but the choices of window type are more limited than audio testing SW.} Because of the lack of smoothing, you just have to up the averaging to smooth out the graph lines, which takes a lot longer than hitting a smoothing command. Waveforms is miles better than the freeware add-on I talked about up top, but it still doesn’t have smoothing, at least as far as I can tell. And lacks the nice little conveniences for audio testing like a quick and easy THD+noise overlay window.

Edit 2: Bottom line:  IMO, AD2 is a great little scope and test suite that covers a lot of bases, but you’ll probably not fully replace your soundcard + audio test SW with it. If you don’t own a scope and/or function generator, it’s definitely worth a look. Even if you do own those tools, the SW and peripherals make it a very useful addition to consider for your kit. As a whole, it makes performing many types of tests a whole lot quicker and more convenient than if you had to set them up with traditional tools.
 
Hope this is helpful.
« Last Edit: August 27, 2019, 09:32:06 AM by rackmonkey »
Whether you think you can or you think you can't, you're probably right.


gyraf

Re: Digilent Analog Discovery 2
« Reply #21 on: August 27, 2019, 02:52:28 AM »
..thanks for the update, still following from sideline..
..note to self: don't let Harman run your company..

Re: Digilent Analog Discovery 2
« Reply #22 on: August 27, 2019, 08:52:00 AM »
thanks for the update.

12afael

Re: Digilent Analog Discovery 2
« Reply #23 on: August 28, 2019, 03:29:36 AM »
AD2 and REW is a great combo. Other piece of software that is very useful is izotope RX 7
heavy metal is the law!!!

Re: Digilent Analog Discovery 2
« Reply #24 on: September 30, 2019, 05:12:49 PM »
AD2 and REW is a great combo. Other piece of software that is very useful is izotope RX 7

You can use REW and the AD2 together?

rackmonkey

Re: Digilent Analog Discovery 2
« Reply #25 on: September 30, 2019, 07:26:31 PM »
I think he means that AD2 and REW are a good compliment to each other, rather than that they can be used together. They aren’t interactive (at least in my experience). I know of no way to make REW “see” the AD2 as the soundcard it uses.

But I agree that they are two useful tools that together give you a lot of test/measurement functions.
Whether you think you can or you think you can't, you're probably right.

Gold

Re: Digilent Analog Discovery 2
« Reply #26 on: July 03, 2020, 06:12:32 PM »
I just downloaded the Waveforms software to take a look. It installed without incident on a MacBook Air running 10.12.6
I have a Presonus Audiobox USB96. USB 2.0 compliant. It came up in devices without any prodding. It generally seems to be working but needs to be calibrated. I'm going to play with the software for a little while before buying the AD2 hardware.

The main issue people have seems to be the AD2 hardware being 14bit. There were choices to operate the Presonus in 16 bit or 32 bit mode at either 48K or 96K. Hopefully I will be able to get accurate low level measurements.

abbey road d enfer

Re: Digilent Analog Discovery 2
« Reply #27 on: July 03, 2020, 06:31:15 PM »
Paul, I tried to answer your PM but your  inbox is full.
Who's right or wrong is irrelevant. What matters is what's right or wrong.
Star ground is for electricians.

Gold

Re: Digilent Analog Discovery 2
« Reply #28 on: July 03, 2020, 06:56:34 PM »
I just cleared out some space in my PM.

fazer

Re: Digilent Analog Discovery 2
« Reply #29 on: July 08, 2020, 02:32:16 PM »
AD2 is sold out and will see a price increase due to component cost increase.   It looks like a cool piece of kit.  gonna be a while before its even available to try for me.   


Gold

Re: Digilent Analog Discovery 2
« Reply #30 on: August 15, 2020, 04:15:06 PM »
Digilent is filling back orders now and think they should be able to fulfill new orders in October. The new price is $399. I've been playing with the software and I like it better than REW and some of the other usual suspects. I especially like that it's an integrated hardware software solution.

I've been checking it out with a Native instruments Komplete Audio 2 interface. I'll also build that Pete Millet interface box. I can switch over to that setup when I need low level measurements. I think the Analog Discovery will be just fine for everything but low level noise and distortion.

It's cross platform so I'm not sure what I'm going to run everything on. If Waveforms supports multitouch on Windows 10 I'll probably do that. I think a 2 in 1 PC is the best form factor for me.

Re: Digilent Analog Discovery 2
« Reply #31 on: August 17, 2020, 01:21:36 AM »
There is something I don't like about the hybrid hardware/software instruments, and that is that they will be outdated and unsupported before you know it, sometimes a new model comes out or the company disappears. That's why I don't trust the software based oscilloscopes or spectrum analyzers, I'm in for the long haul, I want to invest in something that will outlast me if possible.

You can still buy old HP/Agilent or Tektronix equipment, and it will still be performing well after 30+ years without the need of a computer. The only things I have that are software based are a VNA and a Vector Signal Generator and the reason is because having the equivalent hardware stuff is well beyond my budget.  Another one I have is the Audio Precision System 1 for which I got a USB interface from Duke (Audio1Man on GDIY) that makes it work great on Windows 10, otherwise you are stuck with windows XP ? 98?

To be honest, $399 is not a bad price even if it gets outdated, only problem I see is that you need to buy several add-ons if you want to measure more stuff like impedance and so on, so $399 is the starting point, the RedPitaya is a similar instrument that can reach the 1K if you buy the add-ons. The thing is that whenever I have $400 to spare, I much rather spend it on hardware. Instek makes 100 and 200 MHz MDO scopes that have 2 onboard 25MHz Arbitrary Waveform Generators, a 500MHz spectrum analyzer,  and can do stuff like Bode gain phase plots and they cost around $1000USD,  more than twice the price of the Analog Discovery, but I rather have the real thing.
« Last Edit: August 17, 2020, 01:38:42 AM by Dualflip »

abbey road d enfer

Re: Digilent Analog Discovery 2
« Reply #32 on: August 17, 2020, 07:10:49 AM »
The thing is that whenever I have $400 to spare, I much rather spend it on hardware. Instek makes 100 and 200 MHz MDO scopes that have 2 onboard 25MHz Arbitrary Waveform Generators, a 500MHz spectrum analyzer,  and can do stuff like Bode gain phase plots and they cost around $1000USD,  more than twice the price of the Analog Discovery, but I rather have the real thing.
I have been quite disappointed with cheap DSO's. The graph is noisy as hell and on the one I have, the Bode plot function is not capable of dispalying a Bode-plot, it just indicates level and phase at a selected frequency. I'll check the Instek.
Who's right or wrong is irrelevant. What matters is what's right or wrong.
Star ground is for electricians.

Gold

Re: Digilent Analog Discovery 2
« Reply #33 on: August 17, 2020, 10:19:55 AM »
There is something I don't like about the hybrid hardware/software instruments, and that is that they will be outdated and unsupported before you know it, sometimes a new model comes out or the company disappears. That's why I don't trust the software based oscilloscopes or spectrum analyzers, I'm in for the long haul, I want to invest in something that will outlast me if possible.

When I was starting out the last thing I wanted was a computer based setup. I got an AP Portable One.  I love it but I’d like an FFT function.

I looked at the cheap DSO’s. As I understand it they are hardware software combinations.  I came to the conclusion using a PC was more flexible in terms of upgrades . The Analog discovery also has differential inputs which makes measurements easier in a lot of cases.  If  the AD2 works now I can just keep this setup as is unchanged. It will always do what it does. I don’t see how that’s any different from a hardware box.

I get high bandwidth with the AD2 and low noise with the audio interface.  I also get the measurement style front end both ways.

There are a few add ons for the AD2 but none of them are necessary for most audio measurements.

Re: Digilent Analog Discovery 2
« Reply #34 on: August 17, 2020, 11:53:51 AM »
When I was starting out the last thing I wanted was a computer based setup. I got an AP Portable One.  I love it but I’d like an FFT function.

I looked at the cheap DSO’s. As I understand it they are hardware software combinations.  I came to the conclusion using a PC was more flexible in terms of upgrades .

Paul, perhaps you misunderstood me,  a DSO is of course a software/hardware hybrid, but that is what its called an embedded system.  A Tektronix/Rigol/Keysight or whatever DSO doesn't need an external PC to run, right now there is the AD2, when version 3 or 4 or whatever comes out, AD2 will probably no longer be supported over time, and you'll probably replace your PC with a newer one or with a new OS and you'll realize that the AD2 that you own is now useless, granted that may not happen for quite some time, however, that doesn't happen with the hardware DSO, as long as it works it will keep on working over the years

Anything that relies on a OS or a PC is destined for obsolescence, unless you are willing to keep an old PC just to run it, like many of the AP SYS1 owners do. For example, I have a perfectly good M-Audio sound card for which the last drivers were made for windows XP,  I cannot use it under Windows 10, I had to buy a new sound card instead, thats the kind of thing I don't want for my test equipment to go through.

Re: Digilent Analog Discovery 2
« Reply #35 on: August 17, 2020, 12:02:16 PM »
I have been quite disappointed with cheap DSO's. The graph is noisy as hell and on the one I have, the Bode plot function is not capable of dispalying a Bode-plot, it just indicates level and phase at a selected frequency. I'll check the Instek.

The Instek seems to work really well, this guy https://www.youtube.com/watch?v=S5t4AKgV3W4 uses it all of the time in his videos, I haven't looked at the entire spec sheet but what I've noticed is that the noise floor is not that great so it may not be the best to measure low noise electronics, the distortion spec of the AWG is not that great either but I don't plan to measure THD with it anyway, however, the spectrum analyzer and bode plots seem to be quite good.  The MSO version of the guy in the video is the 4 channel 200MHz version, which is over my budget, the $1K im refering to is exactly the same but with 2 channels and a 100MHz BW, both spectrum analyzers have 500MHz BW and the 2 AWG are 25 MHz.

I have a Tektronix DSO, it has a color display and 100MHz BW, its not one of the newer ones but the FFT is absolutely worthless. I would love to have one of the new Tektronix MSO scopes with 1GHz BW, but its either that or paying up  whats left of my house mortgage.
« Last Edit: August 17, 2020, 12:14:44 PM by Dualflip »

Gold

Re: Digilent Analog Discovery 2
« Reply #36 on: August 17, 2020, 01:25:12 PM »
Paul, perhaps you misunderstood me,  a DSO is of course a software/hardware hybrid, but that is what its called an embedded system.  A Tektronix/Rigol/Keysight or whatever DSO doesn't need an external PC to run, right now there is the AD2, when version 3 or 4 or whatever comes out, AD2 will probably no longer be supported over time, and you'll probably replace your PC with a newer one or with a new OS and you'll realize that the AD2 that you own is now useless, granted that may not happen for quite some time, however, that doesn't happen with the hardware DSO, as long as it works it will keep on working over the years

I understood you. As I understand it the scopes as embedded systems are basically a PC in a box. They run either Linux or Windows under the hood.  I know Rigol has offered software updates to their scopes. I know someone that has an old Rigol that can't be updated to the newest software. I don't see the difference between a DSO becoming obsolete to upgrades and the AD2 becoming obsolete to upgrades. I look at this as a closed system anyway. I don't want the test setup in the same box as my DAW or office computer. I could care less whether it runs under Windows 98 or Windows 10. I need to keep the office computer up to date for quickbooks and excel. Other than that, as long as what I have works I don't see a problem.

Re: Digilent Analog Discovery 2
« Reply #37 on: August 18, 2020, 02:51:12 AM »
I understood you. As I understand it the scopes as embedded systems are basically a PC in a box. They run either Linux or Windows under the hood.  I know Rigol has offered software updates to their scopes. I know someone that has an old Rigol that can't be updated to the newest software. I don't see the difference between a DSO becoming obsolete to upgrades and the AD2 becoming obsolete to upgrades. I look at this as a closed system anyway. I don't want the test setup in the same box as my DAW or office computer. I could care less whether it runs under Windows 98 or Windows 10. I need to keep the office computer up to date for quickbooks and excel. Other than that, as long as what I have works I don't see a problem.

That is ok, for me its just cumbersome needing a separate old computer just to run outdated software. Also, the resale value on that kind of equipment is usually not good (AP being the exception), for instance try selling a ProTools HD PCI-x accel card, they used to cost thousands now they barely cost a hundred.