Hi, I know nothing about audio or electronics and have been one of those people relying on chatgpt to try to do something above their pay grade.
Tldr: Can a two-lead geophone work with pre2 of the qa472 preamp at all?
I have a project that I need a geophone for, and chatgpt recommended the qa472 as a good Preamp for an R.T. Clark 4.5hz geophone. (I will try to post a link to that product at the bottom.) I purchased the plain two-lead ending for the geophone initially, no connector, and used an XLR adapter to plug it into pre1, and then to a Zoom h5 studio recorder/interface, then going digitally to my pc, and everything went great. There is some noticeable buzz in the system which I’ve been unable to get rid of, which ai’ve chalked up to being introduced either at the XLR adapter connection (I am horrible at soldering) or at the less-shielded lead wire of the geophone (combined with being in an electrically active environment, rather than the outdoors).
However when I tried to repeat this with pre2 (using bnc now) I’ve run into issues. The buzz is intense and either obscures all data, or there is a loss of sensitivity alongside the intense buzz. I’ve tried multiple adapters and cables, and when that didn’t work, I purchased a third geophone with a factory-installed bnc connector, but that didn’t help either. So it’s not the geophone, bnc cables, or adapters. I’ve also tried changing interfaces and XLR ports of the same (h5 studio) interface.
I’m reaching out because at this point chatgpt doesn’t seem to be very certain as to what’s going on. The only guess it seems to have is that geophones just won’t work with the high-impedance unbalanced nature of pre2 (but earlier on it seemed to think this would be better, not worse). Maybe there’s something obvious chatgpt isn’t seeing? I’d basically just like to have a human-confirmed answer as to whether a geophone of this construction could ever work in pre2 of the preamp, or if there’s any troubleshooting I might want to try.