How much wattage would I need? (Poweramp for digital preamp)

Diego

New member
I'm currently on the fence between getting a Digitech GSP1101 rack, or simply using a Notebook with Amplitube 3 + MIDI foot controller as a preamp.
I'll be working for a while as a session guitarist (got 3 proyects lined up at a studio) so I'll need something portable and versatile.
Hard to beat one of these for me.

I'd need a poweramp, and I've read that a really powerful SS poweramp is the way to go for this kind of use, rather than a tube preamp,
so that the sound the digital preamp generates doesn't get colored at all and it's as clean as possible.
You'd want a tube poweramp with a tube preamp, but not here. At least I've read that.

As a sidenote, I remember somebody on this forum that had a GSP1101, a SS poweramp,
some nice cabs and he couldn't tell the difference between his Peavey 5150 and the 5150 model on the Digitech.

So let's assume that a SS poweramp is the way to go.
How many watts would I need? Consider I'd power a 2x12 cab loaded with proper guitar speakers, and it'd be used for all styles, from Hard Rock to Pop, from bedroom to gigs,
and that I don't truly need insane amounts of power, but it's got to be loud and pristine clean if for some weird reason I need it to.

I'm browsing and I see all sorts of crazy numbers for us guitar players, starting from 200 watts and up to 1000 and all sorts of price ranges.

Could I get a hand on this? I don't know much about rack units. I'm truly clueless on this one.
 
Re: How much wattage would I need? (Poweramp for digital preamp)

The sensitivity of the drivers will be a big factor. When you drop that number in a given speaker, you have to increase the power significantly to play at the same volume. I can't remember exactly, but it's something like, for every 3dB you give up in sensitivity of your drivers, you have to have twice as much power to play at the same volume. But it's late and I'm tired, so… hey, Family Guy is on!

The other thing is, I'd be tempted by a Class D amp. They run cool and efficiently, they're light, they don't take up a lot of space, and a good Class D amp should be able to double its 8-ohm power rating into 4 ohms, easily.
 
Re: How much wattage would I need? (Poweramp for digital preamp)

Tube amps are conservatively rated, and most guitarists push them into a bit of distortion when playing live. To keep up with that, you'll want twice as much power as they have, just to be heard. Most of them generate a good 50-60% more power at full distorted output than their rated clean output. Plus they load differently than a solid state power amp.

If your speakers are more efficient than theirs, that'll help as well. If they are lower... ouch. Jessie's Ghost is right, 3dB increase is twice the apparent volume [3dB decrease is half].

You also wont want to exceed your speakers rated output by much, or you may wind blowing them.
 
Re: How much wattage would I need? (Poweramp for digital preamp)

Look for a two channel amp from 50-100 watts a side that operates in bridge mono mode. Most good PA power amps do. That will give you 100-200 watts when the amp is operated in bridge mono mode. Amps in this power range are most likely not fan cooled and that would be a plus in the studio where fan noise could be an issue. And do consider how much power your cab will handle. (probably 100-200 watts with modern speakers)
 
Re: How much wattage would I need? (Poweramp for digital preamp)

Thank you guys!
Sly, that sounds about right. Plenty of affordable choices in that range, like the Samson Servo 200.
I'm still getting my head around all of this.

I'll let you guys know when it's time to choose speakers for the cab. :D
 
Re: How much wattage would I need? (Poweramp for digital preamp)

That's going to be my next set up. I'm pretty set on getting the GSP1101 and a tube power amp. I don't play live very often so this would be a good recording rig that gives me flexibility to go live when i need to. Hopefully I'll be ordering my GSP in 2 weeks and use my Heads power amp until i trade it in for an actualy tube power amp. Long term I'll also be trading my 4x12 cab for a Buzzbomb 2x12. Basically I'm going for a high powered compact rig that will sound bigger then what i'm using right now. 50-100 watt tube power amp is more then enough power. You could try to seek out peavey classic 120 or 50/50 power amps. They are usually very well priced. usually around what you'd pay for a new SS one. Or even Cravin power amp (don't recall model #)
 
Re: How much wattage would I need? (Poweramp for digital preamp)

for like a day a long time ago I owned a carvin SS power amp and an ADA MP-1. It was the most lifeless setup I've ever played through and I quickly rid myself of both. I've always wondered if a tube power amp would have sounded better...
 
Re: How much wattage would I need? (Poweramp for digital preamp)

This guy convinced me a HD 500 POD can sound really good. Just a suggestion.

 
Re: How much wattage would I need? (Poweramp for digital preamp)

I certainly think there is difference between the SS and tube power amps. the SS seems to have some stiffness to them in my experience but most of them aren't really designed for guitar, more for club sound systems. Those VHT Ninety-two-Ninety are awesome power amps but they cost as much as a good head. I hear many people rave about the MP-1 but most have had the 3Tube mod done so that changes things a lot. With the 3T mod I hear people can pull off 5150 and Dual Rec gain sounds. If at all possible though, it is preferable to track down a good tube power amp.
 
Re: How much wattage would I need? (Poweramp for digital preamp)

It has been said that with amp modellers that you need a good clean power, not something that will break up and have a character of it own.

The person you're thinking of was Xcessive, who used a GSP and an ART SLA-2 Poweramp. Which is 200 watts per side, 560 watts bridged mono to 8 ohms.

That is a lot. But again, rather have too much than too little.
If you only have a 120w cab, I would be hesitant about running 560 watts into it.

An ART SLA-1 (100W per side, 260 Bridged to 8 ohms) would less than half that power, and that's about where the solid state heads I've seen fall into place. IE Marshall mode for has a 350W power section. Randall Warhead has a 300W power section.

If you do get the GSP, you might want the controller, unless you already have something midi.
 
Re: How much wattage would I need? (Poweramp for digital preamp)

I certainly think there is difference between the SS and tube power amps. the SS seems to have some stiffness to them in my experience but most of them aren't really designed for guitar, more for club sound systems.

These modern modeling racks do emulate the tube power amp section too.
So having a real tube poweramp cooking while the power amp is being emulated wouldn't be like having cab simulation on while using a proper guitar amp cabinet?
At least that's what makes sense to me about having a very clean SS power section for this kind of thing.
Not that I know much about this kind of thing, honestly.
 
Re: How much wattage would I need? (Poweramp for digital preamp)

oh yeah, if you're running into a cab, you HAVE to turn cab simulation off. Regardless of what kind of poweramp you have.

Tube poweramps usually come with extra controls like Presence and Resonance, which you may or may not need. With the GSP, you probably don't because you have 2 EQ's you can access to add those qualities.
 
Re: How much wattage would I need? (Poweramp for digital preamp)

These modern modeling racks do emulate the tube power amp section too.
So having a real tube poweramp cooking while the power amp is being emulated wouldn't be like having cab simulation on while using a proper guitar amp cabinet?
At least that's what makes sense to me about having a very clean SS power section for this kind of thing.
Not that I know much about this kind of thing, honestly.

I understand what you mean, but I'm just saying from my experience and what i've heard is they sound stiff. BUT this has been with power amps that you would use in a PA/Pro audio (Crown, QSC, etc) setting rather then using guitar specific power amps. Tech21 and rocktron both have/had SS power amps specifically for guitars.

http://backstage.musiciansfriend.com/product/Velocity-300-150W-Rack-Power-Amp.site1prod584205.product

Again this is just what I've heard and it's my opinion. I'd go with the ability to use the other components (speakers, power amp, etc) to mould the sound more instead of just using a pre-amp and then routing it through a sterile power amp and sterile speakers they would not influence the sound.

It would be pretty cool if somehow you could use the modeling software to mimic things like 5150 loaded with EL34's power section.
 
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Re: How much wattage would I need? (Poweramp for digital preamp)

Allan Holdsworth used to take a line level out from a speaker emulator on one amp and run it into the line in on another tube power amp to get extra power tube saturation.

The real problem is stacking speaker emulation on top of speakers designed for music creation rather than reproduction. That gets muffled and harsh at the same time, can get really weird.

You wont have as flexible a setup if you follow Matt4president's advice, as you'll be limited by the character of the speakers and power amp chosen, but it may sound better for what it specializes in.

PA power amps can sound odd with a tube preamp, but tend to work well with a modeller. There used to be a fair number of FET power amps that did a better job of sounding like a tube power amp. MosValve in particular. The all-tube craze killed a lot of them off before they could really get a fair shake, sadly.
 
Re: How much wattage would I need? (Poweramp for digital preamp)

If your main focus is recording then you don't need to worry so much about using a power amp so much. Every video I've seen though on youtube of the GSP1101 is used with a yube power amp. Whoever said they had a hard time telling the difference between a 5150 head and the 5150 Model on the GSP probably ran that GSP through the 5150 power section. You should probably try it through both a tube power section and a solid state one and see which is going to suit your tastes.
 
Re: How much wattage would I need? (Poweramp for digital preamp)

Best SS power amp I've ever heard/owned is the older style, 2-space Rocktron Velocity 300 stereo power amp. I've got one and it's a beast! 300 watts (150 a side at 8 ohms, 300 bridged at 4 ohms). It's got a "Reactance" control on it that really does simulate tube sag VERY well. Running my Eleven Rack into it, into a Marshall 4X12 loaded with four G12-T75s is bliss. I still prefer my Bogner rig, but that 11R/Velocity setup would be just fine with me for gigging. When you turn down the reactance control, it becomes more like a regular, clean PA amplifier. I find that I prefer the reactance set at noon.
 
Re: How much wattage would I need? (Poweramp for digital preamp)

3 db might take twice the electrical power, but it's only the thresh-hold of being able to hear a difference in volume. 10 db is double the volume at the speaker, which takes ten times the power from the amp...a 150 watt amp into the same speaker as a 15 watt amp, is twice the volume. I went from G12K-85 speakers, rated at 99db, to Cannabis Rex speakers, rated at 102, for my vertical 2x12, and it's not twice as loud, but is noticeably louder than before.

Diego, look up a Tech 21 Power Engine...they're specifically voiced to run digi pre amps and modelers.
 
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