QuantAsylum QA400 and QA401

Thanks MarkS, jsantoro,
There is a known problem with Windows 10 v.1802. Haven't tried the latest which is 1803 cause I sold mine. If you are on 1802 downgrade via control panel and it will work
Nuts, I just got the laptop up and running again and wouldn't you know that Windows upgaded to the latest version of win10. I should be able to deinstall to v. <1802...or if 1803 maybe...I hope.

Cheers
 
Thanks MarkS, jsantoro,

Nuts, I just got the laptop up and running again and wouldn't you know that Windows upgaded to the latest version of win10. I should be able to deinstall to v. <1802...or if 1803 maybe...I hope.

Cheers
Back when it was being pushed really hard, I had a laptop spend about eight hours upgrading to win10, but when it was done and asked "Do you agree to the terms of service, bla bla bla?" I clicked NO and it spent another four hours or so uninstalling, but it did prevent win10 from installing.
 
"For turntable noise rumble, the lower bound on the input is set by the input RC network, and it has a corner around 1 Hz or so. You can definitely measure down that low, you just need really, really long FFT sequences. If you take the output and route it to the input on the QA401, and switch to FR mode and set the source to white noise, and set the FFT length to 256K and averaging to 5, you should see a really nice plot emerge of the overall input response. You will see the overall response is down about 8 dB at 0.6 Hz."

From: https://quantasylum.com/blogs/news/swept-measurements
 
Q100 and Q400 works with windows 8.1, it does everything I that want to do.

However I recently re-measured one amplifier, results were different but especially I have an issue with the Q100 oscilloscope.

Q400 measures a ruler flat frequency response

Q100 measures a declining high frequency response. (peak to peak relative to 1khz is declining steadily from 5khz)

I have no clue of what is going on. Maybe I should measure with REF on the probe instead of the 1X?
 
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The QA401 works fine on Win 10 (for now, ver 1803) but Microsoft has a really bad habit of breaking Windows lately. The QA400 has problems with win 10 or at least did. I don't have one on hand to try but maybe someone else has recently since the USB part of Windows is such a moving target.
 
Thinkig of buying a QA401, what is the minimum PC needed?

I'm very impressed by the QA401 analyzer, but before I plop the required 450€ or so, I need to understand what the performance requirements are for the controlling PC.

Can people here enlighten me on this issue?

Can a totally fanless media-player-style PC like the Minix Z83-4 cope with the requirements?
 
Hi, this is Matt from QuantAsylum. I've never quite understood the rules on commercial postings on forums such as DIY Audio and thus I've opted to steer clear of the issue by not posting about our products...But there's a QA401 user that has just finished a non-commercial & really solid open-source ASIO driver for the QA401 and I think it's important to have several folks try this on their favorite app to see how it runs. The author (Etienne Dechamps) favors REW, I tend to use ARTA, and I've also exchanged emails with a Matlab user that has confirmed it works. That's 3 apps. But that's a drop in the bucket for ASIO.

If you have a favorite piece of software that supports ASIO and you'd like to give it a try, please do! Etienne is very active on Github (UK time zone) and I was thrilled to help a bit by providing technical details how to talk to the QA401.

Issues can be reported to the author here:

Issues * dechamps/ASIO401 * GitHub

The latest releases can be found at the link below. Etienne packaged it into an installer that you run and it handles all the unpleasant stuff that's part of ASIO setup.

Releases * dechamps/ASIO401 * GitHub

After you run the installer, the steps are:

1) Close all ASIO apps
2) Run the QA401 app and plug in the QA401. This will configure the QA401 hardware.
3) Close the QA401 application but leave the QA401 plugged in.
4) Start your favorite ASIO app and select the Asio401 driver.
5) Verify sound in and out

If you unplug the QA401, it will need the QA401 application to reconfigure it again.

Thanks, and again, if this is construed as a commercial posting please accept my apologies in advance.
 
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Matt-
Thanks for sharing. I don't think this type of post would be considered a commercial issue but the moderators would decide. The ASIO driver will be really interesting. My QA401 is on loan to a friend and I'll need to get it back to explore this development. One app worth an immedate test would be DiAna DiAna, a software Distortion Analyzer DiAna Index of /diana/ since it has some novel and very useful analytic tools.