I asked Tech 21 tech support and this is what they send me. I will use this live 98% of the time so it's important to get that tone in my head and they did explain how. here it goes...
Hope that helps....
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Dear Cool,
Thanks for your inquiry, and strap yourself in... there's a lot of info coming your way!
First, I'll remind you that the GED-2112 uses two preamp sections that have separate outputs (Geddy's specification), so unless you have a mixer (don't use a Y-cable or A/B/Y box) to combine the signals to feed your GK, here's our official statement:
Thanks for your inquiry. The preamp can be modified to allow the blended signal at all four outputs (XLR Deep, XLR Drive, 1/4" Deep and 1/4" Drive). and "Mute" can be changed to "Bypass".
Note: These mods must be done by a qualified technician or the warranty will be voided. You can have your tech contact us for further information by emailing this same address:
[email protected]
If you’d like a “quicker” method for mixing the channels, you can run a short cable from the Deep section’s 1/4” Output, set for 0dB (button pushed in) to the Effect Return with the 50/50 mix engaged (button pushed in). Then run from the Drive section’s 1/4” Output to your amp, and/or the Drive XLR Out to the PA.
Start with both Level controls at 12:00. The Drive Level will now serve as a “master volume”, and the Deep Level will allow you to “blend in” the clean signal.
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Once you have the signals combined, here are FIVE ways to connect to your GK (the draft describes a SansAmp RBI with a MESA amp, so just substitute GED-2112 and GK for those):
You have a few options:
1) You can skip the MESA's preamp section entirely by running from your instrument to the RBI's input, and from the RBI's Effected 1/4" Output to the MESA's Effect Return (sometimes labelled Power Amp In). This will send the RBI preamp signal straight to the MESA's power section. But you might skip all the MESA's knob controls, too, and the RBI's Level knob will serve as your "Master Volume". So be sure your instrument's volume knob is all the way down before you power up the MESA... otherwise, it may be very, very loud!
2) You can connect your instrument to the RBI's front input and run its Effected 1/4" Output to the MESA's front input (or rear input, if you're wired up in a rack). With the RBI in bypass, set the MESA for its "best" tone, and add the RBI as a "monster overdrive pedal". You'll probably have to ignore the sample settings in the owner's manual (which are intended for direct recording without an amp) and set the RBI so its tone is "complementary" to the MESA's own character.
3) You can connect your instrument to the RBI and run the RBI to the MESA's front (or rear) input, but this time you'll set all the MESA knobs halfway up, so there isn't too much or too little of anything (for the most "neutral" tone you can get from it). This will allow you to leave the RBI settings closer to the samples in the manual, but some tweaking may still be required.
4) There may also be a way to "shuttle" back and forth between one preamp at a time (like having a two-channel bass amp), if the MESA's effect loop is footswitchable (on or off). You'd plug into the RBI's input, then go from its Uneffected 1/4" Output to the MESA's input, and from its SansAmp 1/4" Output to the MESA's Effect Return. When the effect loop is off, you'll get the MESA's preamp, and when it's on, you'll get the RBI.
Looking at the photos of the MESA, I don't see a footswitch for the effect loop, so an alternative would be to use an A/B box (even if it means adding a few more long cables). In that situation, you'd run from the MESA's Effect Send to Input A of the box, and you'd run from the RBI's SansAmp 1/4" Output to Input B of the box (instead of directly to the MESA's Effect Return, as described in the above paragraph). Then, you'd run from the A/B box's output to the MESA's Effect Return. So when you select A, you get MESA preamp, and when you select B, you get RBI.
5) The last thing to try is running your bass to the MESA's input, and from the MESA's Effect Send to the RBI's rear input (with the -10bB pad engaged, to "knock down" the MESA's hot, line level signal). You'd then run from the RBI's SansAmp 1/4" Output to the MESA's Effect Return. You can add a standard, latching type footswitch (the kind where you can feel a "click") to the RBI's footswitch jack to turn it on or put it in bypass.
If you're wondering why I didn't simply recommend this in the first place, it's because the hot signal from the MESA's Effect Send might cause the RBI to over-compress or break up in an "unmusical" way. You never know, until you try it at "performance volume".
We encourage you to try all these methods, and choose the one you like best.
I've never seen so many inputs on a piece of gear!
