FX8 and ISP Theta preamp

Hi, I was going to use an ISP Theta preamp with an FX8, and a stereo tube power amp.

use the relay 1 & 2 with the external control jacks on the Theta to
control jack 1: switches gain A or B.
control jack 2: turns on, off preamp 1, and preamp 2(distortion)

I tried some different settings for Relays,
and it now is working well.
If anyone else is using a Theta preamp
with an fx8? wondering if there
is a way to get complete functionality
of the two external control options?
 
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The Theta preamp has two Control jacks for connecting to relays or switches. Each jack controls two different things using tip and ring, as labeled on the back of the preamp. That's four things that can be controlled.

By coincidence, the FX8 has two relay jacks. Each jack controls two different things. That's four things can be controlled.


So yes, you can do what you want, but you'll need two cables that are TRS on both ends.
 
The Theta preamp has two Control jacks for connecting to relays or switches. Each jack controls two different things using tip and ring, as labeled on the back of the preamp. That's four things that can be controlled.

By coincidence, the FX8 has two relay jacks. Each jack controls two different things. That's four things can be controlled.


So yes, you can do what you want, but you'll need two cables that are TRS on both ends.
ahh the Theta uses TRS for relays, didn't know that. then yup, a TRS cable for each connection sounds like it'll do the trick!
 
One other question,
I tried the Theta first in the signal
chain, before the FX8, and now I have
it in the loop, using a similar preset as i use
with a guitar amp
and it sounds very good this way.
is there a best place for the preamp in
the signal chain?
should i keep it in the loop?
 
One other question,
I tried the Theta first in the signal
chain, before the FX8, and now I have
it in the loop, using a similar preset as i use
with a guitar amp
and it sounds very good this way.
is there a best place for the preamp in
the signal chain?
should i keep it in the loop?
That’s up to you. Are there effects you want before the preamp? Put the preamp after those. Are there effects you want after the preamp? Put the preamp in front of those.
 
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