There are a couple of ways to do this with the latest release. The most appropriate is to go to the Response/Impedance/Gain tab and run it a Response test. I usually use Chirp (slightly less accurate but much faster).
I did this test yesterday with a preamp and so it’s kind of a bad photo because the response is virtually flat so I had to zoom way in on the Y axis but it’s very representative.
There are changes planned for this to show the bandwidth results (not just the chart) and add some smoothing but tbd.
@Blueglow- I was looking at the frequency response filter plot and wondering where that was in this program, and then recognized it was a VEE program! I miss using VEE- if it was programmable with the QA403 (possibly it could be, but setting up a usb interface was difficult from what I remember.
Hey Mark,
When trying to run a frequency sweep past 20khz (50k end freq), I get this error. Is this by design? I know a lot of analyzers top out at 20k on their graphs but it would be helpful to see other a devices ability to produce artifacts beyond 20khz.
Per user (@peppermint ) request I’ve just posted a version (1.1.3) that supports dBu and other display formats. The list of formats is pretty much copied from REW so let me know if any are missing or I’ve missed any connections.
I run a QA402. After v1.1.1 the Calculating DUT Gain and Determining Noise Floor both run really slow then the app no longer responds at Measuring Spectrum… I have tried both v1.1.2 and 1.1.3. Thank you for your work on this (and PC Paintbrush!).
Wow, I don’t have a QA402 around. The code change at 1.1.2 was changing to direct USB. So, it’s likely that’s the issue. I did have some problems with that first scan that seem to finally be fixed in the very latest build but what you’re seeing is surprising.
There were changes made to the noise analysis (repeatedly) because I found that the first acquisition after changing parameters hadn’t settled yet - so it may be a generic (vs hardware) bug.
I wonder if @matt has any guidance for QA402 differences via USB.
Does anyone else have a QA402 they could try with or have tried with QA40xPlot?
I’ll look into adding some diagnostic output but it’ll be a bit since I’m working on file save at the moment. I can probably detour after finishing the spectrum upgrade.
I thought v1.1.0 was the initial to USB. v1.1.1 does not need QA40x running in the background. Did some more testing this morning with v1.1.1 using an external generator. I “think” QA40xPlot’s inputs are reversed. Must enable Right to see input from Left. All is OK on QA40x latest version with external gen. Thanks
Hi there. A new guy here
I found the topic on Blueglow’s YouTube channel. I have the QA400 model, that works only on Windows 7. I tried the MarkZ software on my Win10 PC, but as I expected, it doesn’t work.
So, is there any chance to make the older audio analysers from QA compatible with this software?
What do you think, Mark?
Hi, re: the QA400, QA401
I looked around the low-level code I could find for the QA devices and it seems to boil down to the QA401 has different input and output ranges from the 402/3 which I can easily handle and different buffer size requirements, which I can ignore. Unfortunately I couldn’t find much beyond that other than ASIO401 works with the QA401 but seemingly requires the user to reboot it before use. I didn’t see any discussion of the QA400.
It would be really hard for me to implement without a device - although if it’s just the two ranges that I can easily handle. If they all support the same REST code - I may look into adding back REST support as an option.
Conversely, the code is open source->
98% of the usb code is in a single module named QaUsb.cs so it’s pretty easy to look through. A file QaLowUsb.cs has the very low level usb attach by number.
Hi @BarryLambert
Perhaps you could send me a message and we can take this offline. I’d really like to fix it but can’t replicate the problem here and it may get rather wordy… your account is closed to messaging.
I’m going to run a utility called process monitor and see if I can see anything unusual first. I am in Montreal Canada and I’m not sure if I can text to the US. I do have canada-wide texting. Could also use Facebook Messenger or..simple email computeruser AT sympatico.ca (AT=@)
I have a log from Process Monitor. (ProcMon from Sysinternals). The best viewer for the log is ProcMon itself. The log is from when I exe QA40xPlot until terminated in Task Manager due to no response. Some of the processes in the log have been filtered out so the log is easier to read. All I need to do is get this log to you. Here are two examples (and maybe the error)
6:07:42.3832265 PM QA40xPlot.exe 2452 CreateFileMapping C:\Program Files\Audua\QA40xPlotSetup\FftSharp.dll FILE LOCKED WITH ONLY READERS SyncType: SyncTypeCreateSection, PageProtection: PAGE_EXECUTE|PAGE_NOCACHE
and
6:07:42.3554468 PM QA40xPlot.exe 2452 CreateFileMapping C:\Program Files\dotnet\shared\Microsoft.NETCore.App\9.0.3\System.Threading.Overlapped.dll FILE LOCKED WITH ONLY READERS SyncType: SyncTypeCreateSection, PageProtection: PAGE_EXECUTE|PAGE_NOCACHE
Hi Mark
Great software, great work!!
This makes the QA403 so much easier to use!!
I live i Denmark, and clicking the Power Markers gives me the frequencies of US, not the 50 Hz used here. I have checked my regional OS settings, and they point to Denmark.
Another issue:
Running THD vs frequency, I cannot see the Noise Floor graph:
) thanks.