DC coupled sound card

#1

I’m an oscilloscope expert (36 years working at HP, Agilent, Keysight, R&S) and somewhat new to oscilloscope music (<20 hours). Most laptops, including mine, have AC-coupled audio output, so low-freq scope music signals aren’t present. I’ve done a quick Google search and found that most Apple products have DC-coupled audio.

Does anyone know of a sound card (maybe external USB-based) that can be used with a Windows 11 laptop to get DC-coupled audio output that is $100 or less? I have a HW-engineer colleague who purchased an AC-coupled USB sound card, took out the capacitor and replaced with a wire…but this modification created some additional issues.

I would think that lots of others have encountered the same issue. Is there some other workaround?

#2

the subreddit will yield more answer to this. https://www.reddit.com/r/oscilloscopemusic/

i don’t have a link handy, but there are rather cheap usb dacs that are dc coupled (e.g. some of the hifi berry accessoiries).

#3

I had the same issue, tried different things, also an old Ipad and Iphone. It worked but not so nice. Than I remembered I had an old raspberry pi 1, with indeed an Hifiberry Dac, and it worked perfect. Still, sharp images, but it could only play wav’s, not generate anything. So now I was convinced of the beauty, I bought an old Motu 828mk2 for 100,- euro. It worked even better, more volume so bigger images, super sharp
I use windows 10, so not sure about 11, but Motu has good drivers for their old stuff. The Motu is really professional and the 828mk2 has at least 8 outputs, but, the LCD backlight is often broken, but that’s why you can find them really cheap and the LCD is a quite easy fix