What if? Tech 21 GED-2112

[scottfeldstein]

I have the YYZ on my pedal board going into my Carvin BX1500 and I'm digging it. But what if...?

What if I got a GED-2112 rack mount preamp instead? What amplifier would I use it with? I was thinking something like the Crown XLS 1502. I could run 300w at 8 ohms per side all the way up to 1500w @ 4 ohms bridged together.

But it looks like the 2112 has two outputs, one for the Drive and one for the Deep. How do you put them both into a single input power amp? Do you get two power amps? That sounds heavy and expensive. I'm must be missing something here.

 

[Raw N Low]

There isn't a full range single that is a mix of both channels. It was designed for Geddy to go ampless.

You could run each out put into each channel of the Crown and tune the drive and deep into two separate cabs. Same principle principle applies to mixer output. The expectation is to run two separate signals and blend to taste.

 

[scottfeldstein]

You could run each out put into each channel of the Crown and ...

Does the Crown have two separate inputs? I don't think it does.

 

[Raw N Low]

Does the Crown have two separate inputs? I don't think it does.

The XLS 1502, correct? If so, then yes it will have two inputs. They should be on the far right behind the amp for channel A and B.

 

[scottfeldstein]

Oh, I see that now! Thanks Weird, it has XLR and RCA inputs but no 1/4". Maybe that's typical for power amps. Even weirder to me though is that there's no single input option. Like if you wanted to use a pedal preamp that had one output, you'd have to pick a side, you couldn't use both.

So. If you had two cabs you could run the Drive side of the 2112 into one side of the amp and into one of the speakers, and likewise with the Deep side into the other side of the amp and into the other speaker. The only way to get both sides of the 2112 into one cab would be to bridge the amp into one output.

I think I have this right now...

 

[SteveIII]

Search for internal jumper. That's how to combine the signals

 

[scottfeldstein]

I see it does have 1/4" inputs now. Missed that before. Here's a new complication, though. If you want to use the amp in bridged mode, you need to use only a single input not both!

I'm puzzled as to how the 2112 is supposed to be used. Always with two amps into two cab loads, it seems. There doesn't seem to be any way to turn it into one output for one cab. But maybe I'm just being a dope. There's a lot I don't understand about this yet.

 

[toddsterbassist]

If I was going to use that preamp live I’d run it into a Rane MLM-42 1 space mixer and send a mixed signal to the FOH and also to a poweramp/cabinet on stage.

 

[scottfeldstein]

If I was going to use that preamp live I’d run it into a Rane MLM-42 1 space mixer and send a mixed signal to the FOH and also to a poweramp/cabinet on stage.

So you could use that piece of equipment to combine the Drive channel and the Deep channel into one output?

 

[toddsterbassist]

So you could use that piece of equipment to combine the Drive channel and the Deep channel into one output?

Yeah it’s a 4 channel mic/line mixer. Mono out. Not sure if they are still in production but you can find them used. I have two of them and they’ve never failed.
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[scottfeldstein]

Yeah it’s a 4 channel mic/line mixer. Mono out. Not sure if they are still in production but you can find them used. I have two of them and they’ve never failed.
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So you get a combined Deep and Drive output, got it. And you can send it to the FOH and to a power amp. Could you send it to ... two power amps? The combined signal, I mean?

 

[Clemouze]

I think you have an internal jumper inside the 2112 to use only one output which then blends drive and clean.
No external devices needed

 

[toddsterbassist]

So you get a combined Deep and Drive output, got it. And you can send it to the FOH and to a power amp. Could you send it to ... two power amps? The combined signal, I mean?

I imagine you could daisy chain power amps.

 

[scottfeldstein]

I imagine you could daisy chain power amps.

No, I'm thinking a 2 channel power amp (that can, if you want, be bridged into one output).

 

[scottfeldstein]

I think you have an internal jumper inside the 2112 to use only one output which then blends drive and clean.
No external devices needed

Gonna read through the manual for this...

 

[scottfeldstein]

Hey, you guys were right! There IS an internal jumper that will combine the two channels into one output! Read about it here:

My method of using Ged 2112 Sansamp through one amp

One wonders why this isn't an exposed feature documented in the manual. Unless you're using this strictly for studio recording it's an obvious thing you would want to do! And if I'm reading this document correctly, it sends the blended signal out through both of the 1/4" jacks and both of the XLR jacks. That is, all four get the blended signal. Nice!

So if I used it with a 2-channel Crown amp as discussed in the OP... I could send blended signals to both sides of the Crown and use each side to power separate speaker cabs. But if I wanted really high output, I could bridge the Crown into one output and still send one blended input signal into it. (The Crown will take only one input when used in bridged mode.)

Ok, this GED-2112 thing just got usable for me in a big way!

 

[scottfeldstein]

This is the document I mean.

 

[scottfeldstein]

And if you follow that other thread I mentioned, there is an alternate method of achieving this same goal.

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.
​

I don't think I would use this method. Most times I would want two blended outputs, not one. I want to use both sides of the Crown independently to power whatever speakers I want (even mismatched). The only time I would need only one output from the 2112 is if I had the Crown in bridged mode. In bridged mode it can only have one input.

 

[Basshappi]

You can run just the Drive channel into your bridged amp and not use the Deep channel or you can move the internal jumper that combines the Drive and Deep channel to the channel outputs.
If you run your amp in stereo you can just run the Drive and Deep channel to the separate amp inputs (R/L) into their own cabs.

edited for correction

 

[labeledbass]

I've had a 2112 for a while now, it will run how ever you want. Drive/Deep XLR out, 1/4 Drive/Deep out (all 4 [5 if you include the thru output] outputs run fine at the same time). You can shift the pins on the jumper for 1 channel operation, or patch the deep onto the return.

Personally I run a chorus after my bass, into the preamp then a compressor 100% wet on the effects loop back into the 50/50 return (effects loop only effects the Drive channel), and my Deep channel is untouched. 3 channels out into a interface blending on the back end.

If I was using in at a gig I treat it as a biamp situation, drive is still compressed post pre, into a 2x10 and the deep untouched into one 15.

The drive on the drive channels attack is input sensitive, not unlike some compressors, so using the drive as an input sens is a good idea for nice pre tube warmth. The deep essentially works the same way with the saturation, except more of a tube power stage being pushed.

"Geddy sounds" aside, it's really a very flexible preamp, you can even get more blend runing the untouched signal back into the return loop to thin the drive out even more.

I would suggest a 2 channel operation to anyone using this for sure, but don't let that put you off if you have only one.