I’m wondering if I can get some ideas debugging my H90 powered pedalboard’s output stage. Specifically I’m trying to get line level out without clipping like crazy.
My core issue is I’m not getting anywhere near line level output from the H90 and even when I crank the output gain on a program, I just start to get clipping. I have a crazy buzz issue, but this is just our church building.
The basic setup is:
H90 Loop A is mono to stereo with TS cables, hits the modelers, back in on Loop B => output to PM351 is a TS reverse splitter to TRS stereo acting as a direct box to FoH.
A bunch of stuff in mono -> H90 Loop A Input1 -> H90 LoopA -> H90 Loop Output 1/2 TS -> Two UA Modelers in series -> H90 Input 3/4 TR -> H90 LoopB -> H90 output 3/4 TS -> Split Cable -> TRS stereo -> Rolls 351PM -> XLR outs + headphone mix.
The H90 Loop B is set with line level inputs and outputs and the input from the UA modeler is cranked. If I Loop B input to instrument, I get a nasty clipping, which I think is coming from the H90 Input 3/4. Turning the Input 3/4 back to Instrument and then reducing the gain removes that clipping, but the signal output from the H90 then drops off so far I can’t get anything useful to FoH. What’s weird is I have the same setup on secnd board with a GFI Duophony as the last pedal set to line level and it’s fine. It’s something about the H90.
Questions:
- Can someone confirm that if the H90 has an instrument input and a line output, the expected behavior is some kind of built-in gain function to match those outputs? Like this should “just work” even when input and output are set to 0.0db?
- Does changing from 9 to 12V increase headroom at all, or is this just purely for less current draw?
Stuff to try:
- I was this many days old when I learned the H90 has TRS balanced outs, so the first thing I’m going to try is bypassing the PM351 direct box section and running straight H90 to XLR to FoH and seeing if that helps. This kill sthe headphone mizer part I need, but I can live with it for live situations.
- I will try to set Loop B back to Instrument input and drop the gain on the modeler and see if I can figure out how to level match at that lower output.
- I’m going to recheck all the cables. I’ll also try an isolated standalone supply for the PM351 to take that out of the equation.
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