Question about preamps...

[Dodger]

Can i plug a preamp into a normal guitar amplifier? As an example say i owned a marshall jmp-1 and a marshall dsl 100 could a i plug the jmp-1 into the dsl? If so could i plug that into the front of the dsl where youd normally plug your guitar in or would i have to use the effects loop?

Im asking because i own a Sovtek Mig-100 and i love the sound of it, its big and ballsy but i wish i could get more preamp gain out of it and i was thinking a seperate preamp could do that job for me but the sovtek doesnt have an effects loop. Can i do this?

[Dodger]

Re: Question about preamps...

Bump

[Kent S.]

Re: Question about preamps...

Loop or power amp input, the input is made for instrument level, not line level. Some preamps have an instrument level output, but that's different, even with FX return or loop input you must be careful with the output level from the preamp, as you never now what the engineering of the system layout is exactly. A good rule of thumb is to try to match the volume of what the original (the amps own) preamp delivers volume wise. If you padded the preamp output enough (read keep it low enough) then you could in a pinch, but be careful as you could toast the preamp you are running into ...

[Dodger]

Re: Question about preamps...

On the back of my amp it has Line out Balanced/unbalanced and then the basic speaker outs. I dont know much bout this sorta stuff wat ur sayings is kinda confusing already. Wats the line outs function? Can i plug a preamp in there?

[Robert S.]

Re: Question about preamps...

A line out is a line level output, not an input. Connecting a JMP-1s output to a line out will cause serious damage in one or both units. Use the effects returns on the DSL.

[sanrafael]

Re: Question about preamps...

The inputs of tube preamp stages are very difficult to burn out, so I do not think you are going to hurt the input.

The Sovtek Mig-100 has a low gain channel, and you might try running your preamp in there. This low gain input skips the first tube that the high gain channel uses, and runs directly to the first volume pot, which is 1 Mohm. You can put many volts into this control without hurting it, and so you can use it to attenuate the output of the preamp to the right level so that you get the right overdrive in the Slovtek. Start with this control on a low number, and work up slowly until you get the right sound. This should do exactly what you want, but you have a lot of possible combinations, and it might take some playing around to get it right.

[Kent S.]

Re: Question about preamps...

Just remember, a preamp want's to see a range that it's comfortable with ... any damage incurred will most likely void your warranty ... feel free to experiement, but be forewarned.

[sanrafael]

Re: Question about preamps...

Actually, overdriving a 12AX7 and feeding 200 volts peak to peak or even more into the next 12AX7 is what guitarists do. The preamp is not comfortable with it; that is the whole pont of overdrive, but it does not get damaged. Connecting an external preamp is no different.

Obviously ss preamps need careful protection from that kind of (mis)use!

[Kent S.]

Re: Question about preamps...

All that aside, I've seen tube preamps get damaged doing that very thing, plus since the JMP-1 is a fully tonal shaping preamp (or is the goal to do all the shaping by itself), it's just not necessry to do the *bolts of volts* routine on the other preamp (not to mention the loss of any clean signal you wanted).

[sanrafael]

Re: Question about preamps...

All that aside, I've seen tube preamps get damaged doing that very thing, plus since the JMP-1 is a fully tonal shaping preamp (or is the goal to do all the shaping by itself), it's just not necessry to do the *bolts of volts* routine on the other preamp (not to mention the loss of any clean signal you wanted).

That's right, one could use the Slovtek pretty much as a clean amp and do it all in the JMP-1, but I think Dodger likes the sound of the Slovtek heavily overdriven and just wants to increase the intensity. He does not really need the JMP-1; a simple preamp with two cascaded 12AX7 stages would do the job. But if he already has the JMP-1.....

[Kent S.]

Re: Question about preamps...

Then the question is whether he just wants a clean boost at the input of the Sovtech's preamp, or some OD from the JMP-1 added in ... apparently I missed the part about him boosting the drive of the Mig-100, when he said the Mig-100 was big and ballsy, but he wished he could get more preamp gain from it, and then mentioned using a separate preamp ... it sounded to me like he wanted to use the preamp for the tone, and the amp for it's power and dynamics.

[Dodger]

Re: Question about preamps...

Thanks for all your replys. I dont own any preamp or boost of any kind yet. Im not looking to change the sovtek tonally. Overdriving The power amp sounds great like i said big and ballsy my only issue is the that really there aint much of a preamp stage to overdrive and clip the signal to creat harmonics and such.

Im looking for the sovteks tone but with alot more power in the preamp so i can get some gain happening to i can make my lead tone sing and do pinch harmonics and stuff in that vain. I know theres always the choice of just putting a distortion pedal in front of the amp but i dont wanna be cheap cause i know that could mess to much with my tone considering most pedals are solid state.

This is why i was considering buying a seperate preamp that i like u know the best of both worlds. Maybe a clean boost is all i need maybe you guys can recommed a good dist pedal that could do what i want without screwing things up to much. Maybe a preamp would be perfect any recommendations will be appreciated.

Edit: Sorry if i confused anyone with the dsl and jmp-1 example im not even considering buying a jmp-1 the preamp i did have in mind though was the Engl 530 its cheap and gets a good rap at Harmony Central, Ive heard Engl's products are quite transparent in there overdriven sound aswell which appeals to me also.

[Kent S.]

Re: Question about preamps...

Have you considered any of the tube overdrive pedals, like the old real tube or such. That might be worth looking into.