Explain this thing with pre/power-amps to me please.

[Leveller]

Well, how do they work. Like a head? I heard that you could just connect a pre-amp into a regular amp and use it as an effect, is that true? The reason I'm asking is becuase I'm thinking of getting a Marshall Jmp-1 pre-amp and maybe a 20/20 el84 poweramp. What are the pros and cons versus a head?

 

[jimmy]

Re: Explain this thingh with pre/power-amps to me please.

Re: Explain this thingh with pre/power-amps to me please.

Well, how do they work. Like a head? I heard that you could just connect a pre-amp into a regular amp and use it as an effect, is that true? The reason I'm asking is becuase I'm thinking of getting a Marshall Jmp-1 pre-amp and maybe a 20/20 el84 poweramp. What are the pro's and con's versus a head?

Pros and cons you ask?

Pro:
Well, you'll be able to get some bitchin' tone, for one.

I was using a Marshall MKII with two pedals hooked up to it (A Dime Distortion and MXR 10 band), then I switched to using a ADA MP-1 Preamp and used my head as a power amp; that setup totally blows the other one away!
The point, here, is that you're able to bybass the old preamp of the head, therefore causing all the knobs on the head useless, and thus using the knobs on the new preamp--the MP-1 for me--to shape your tone and dail in the distortion.
You'll be able to do the same with your stuff (the JMP and the 20/20).

Con:
Depending on what you really want to do with your amp, you might not be able to get all the tones you want--to really depends how you use everything you have. You may also loose a lot of the tone from your head, if you switch to another preamp instead of using the amp's preamp.


I hope all this jibberish helps you in some way. I'm sure someone else can explain it a lot better than I just did.

 

[jimmy]

Re: Explain this thing with pre/power-amps to me please.

One more thing:

If you plug a preamp into a head, you preamp the preamp. That means you'll have to mess with the knobs on the head along with the ones on the preamp.
Most new amps have a preamp bybass that lets you engage just the power stage tubes.

 

[Leveller]

Re: Explain this thing with pre/power-amps to me please.

Thanks! Well all I have now is a crappy solid state combo, so I wont miss anything there =).

 

[Boleslaw Gers 666]

Re: Explain this thing with pre/power-amps to me please.

To explain exactly what a rackmound poweramp/preamp combo is: it is exactly what a head is. A head is simply a pre and power amp combined into one box. Presence and volume is the power amp section of the head, while everything else is the preamp.

 

[Gearjoneser]

Re: Explain this thing with pre/power-amps to me please.

If you go for a rack setup, I think it's best to run it into a real stereo tube power amp, just since it's stereo and voiced more flat. Don't get rack-itis, where you start thinking more is better. The reason most heads have a more punchy and immediate response, compared to racks, is because there's only one wire connecting the head's preamp to the power section. On a rack, I've found it's best to keep it simple and just use a preamp, FX unit, and power amp. The only other things you need in a rack are a Furman PL-8 with lights, and a blank ventilated rack space to put directly above the power amp to keep it cool, and keep it from heating up another unit.

An ideal rack setup would be a light SKB 8 space rack.
Furman power conditioner
JMP-1
TC Electronic G Major
vented blank rack panel
Any Mesa, VHT, or Marshall power amp

Midi Pedal with all your channels midi-mapped between the preamp and FX unit.

(2) 2-12's, (2) 4-12's, (1) Stereo 4-12 or 2-12.

 

[Leveller]

Re: Explain this thing with pre/power-amps to me please.

Thanks guys! Another question, if the poweramp is 20/20 W, is that like 40W but in stereo or how does it work?

 

[Naps]

Re: Explain this thing with pre/power-amps to me please.

One more thing:

If you plug a preamp into a head, you preamp the preamp. That means you'll have to mess with the knobs on the head along with the ones on the preamp.
Most new amps have a preamp bybass that lets you engage just the power stage tubes.

You mean plug the preamp in the the 'normal amp (pre&post)' input? like where you would plug in a guitar? Or are you supposed to go into the 'in' effect loop? Or can you do both (but not at the same time)?

I'm just wondering if I can plug my Mesa's slave out into my TSL where I plug in my guitar. Or my TSL's 'out' effect loop in to the Mesa where I plug in the guitar.



.

 

[jimmy]

Re: Explain this thing with pre/power-amps to me please.

You mean plug the preamp in the the 'normal amp (pre&post)' input? like where you would plug in a guitar? Or are you supposed to go into the 'in' effect loop? Or can you do both (but not at the same time)?

I'm just wondering if I can plug my Mesa's slave out into my TSL where I plug in my guitar. Or my TSL's 'out' effect loop in to the Mesa where I plug in the guitar.



.

I'm talking about pluging the preamp into the regular input, right on the front of your amp-- that preamps the preamp.

One question, though: Why would you want to plug your Mesa into a Marshall?
From the question you ask, this is the idea I'm getting....

 

[Naps]

Re: Explain this thing with pre/power-amps to me please.

I'm talking about pluging the preamp into the regular input, right on the front of your amp-- that preamps the preamp.

One question, though: Why would you want to plug your Mesa into a Marshall?
From the question you ask, this is the idea I'm getting....

Yeah, that's what I ment by the "where the guitar goes"= front of the amp.
I didn't want to get it confused with the effects loop 'input' so I called it the guitar input.

To answer your question, Just to see how it sounds. Just curious. :newangel:

From what I've gathered (and I may be mixed up) but the Mesa Preamp is where it gets the Mesa tone and the big bottom end. So I was thinking of using it to get more bottom and clarity through my marsall. And vise versa Marshall into mesa. Just curious, but I don't want to blow anything up. :13:

 

[jimmy]

Re: Explain this thing with pre/power-amps to me please.

Try it and tell me what happens....

 

[Leveller]

Re: Explain this thing with pre/power-amps to me please.

This is so getting a bump right now.