Following a suggestion from “enjon” I tried the Room EQ Wizard to get a somewhat more meaningful SNR measurement. Here’s the result:
For the moment I’m happy with -116.1dBA, although there’s still a little room for improvement. The low frequency noise could be reduced somewhat, by moving the HP filter cutoff frequency up a notch, closer to the lowest string frequency.
Of course this still doesn’t compare with professional audio measurement gear but it’s definitely better than my initial simple RMS readout. Alas, I do miss having easy access to an Audio Precision Portable One like back in the days at ZKM.
Three more update tidbits:
- The guitar is connected via 10m of un-shielded (neither per pair nor overall) CAT-5 (Mogami 3367 to be precise). So for the moment I’m quite happy with the robustness of this new A2B link. Will have to see how it behaves under stage conditions.
- Initial tests were battery-powered. Switching to ordinary 12V supplies resulted in increased noise. So I ended up buying a top-notch supply from Funk Tonstudiotechnik – highly recommended gear if you’re willing to invest a bit more.
- As this was not a measurement with shortened inputs but pickups connected, I had to heavily dampen the strings as well as the guitar itself on the table. Without this it acted like a seismometer where any truck passing by four floors below would introduce significant rumble into the system.