IMix Hiss Troubleshooting

[jpbaldwin86]

Hello,

I'm having an issue with an older iMix onboard ("barn-door" style) preamp and was hoping someone may be able to help. My preamp is producing an audible hiss that is more pronounced than other preamps I own. I've troubleshooted the issues down to the preamp itself.

I've tried the unit with a new output jack harness, disconnected the pickups, and the hiss is still there and doesn't change. In addition, the noise doesn't change in relation to the preamp volume, it stays the same weather I'm at 0% or 100% volume on the guitar. In addition, it doesn't change when the mix control is moved from one pickup to the other.

It does, however, increase when the high-end eq slider on the preamp is increased.

I've also made sure that its not due to a gain-staging issues as I'm just plugging straight into an acoustic amplifier. Cables, etc. have also been checked.

My questions are:

1) Has anyone else experienced this?
2) Does the iMix naturally have a higher noise floor than other preamps?
3) Any other thoughts would be appreciated. I'm trying to track down another iMix onboard to compare, but haven't come across one yet.

Thanks,
JP

[Caleb_Elling]

Hey JP,
The iMix doesn't usually have a higher noise floor compared to any other system. I've never seen an iMix have noise like that with the pickups disconnected.

Unfortunately, it sounds like something in the preamp is dying, and as I'm sure you know, replacements for that are no longer commonly available.

[jpbaldwin86]

Hey Caleb,

Thanks for getting back to me, I really appreciate it. It's good to know that it's most likely malfunctioning. I may have tracked down a used one, if not, I'll upgrade to the new iMix units.

I appreciate the help!

Thanks,
Jeremy