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Is something like this possible?

K

KablesP

Guest
Oct 29, 2013
258
15
#1
Would it be possible to have a 100 watt all tube amplifier with a 400 watt solid state power amp as well? The way it would work is that you have your all tube path and once you hit the sweet spot you can make that great sound louder with the solid state amp.

Seems too good to be true...
 
#4
Is something like this possible?
Click to expand...

The way you describe it, no.

It would be possible to reamp the signal of that 100W tube amp with a 400W SS amp but there are several issues why it might not sound identical to 100W amp running on its own and most obiously it would be totally pointless to dissipate 100 watts of nothing but waste power when signal processing can be done in low current high impedance realm where waste power is reduced to couple of watts.

That, BTW, is done by several manufacturers that have introduced their own takes of "tube power amp emulation".
 
#7
KablesP said:
Would I still have to have the tube amp running into a cabinet? Or would it be better to use a dummy load so only the amplified signal is heard?
Click to expand...

It has to be run with a load but I would run a dummy load if I was attempting something like this as I would only want to power one cabinet.

You could slave the tube head, couldn't you? I know my SVT could be slaved. (I only know enough about this to steer you in the wrong direction)
 
#8
Very good thread. I have often seen threads on this board that state you can use use one amps out, to another amps pre amp in. Why is that not right in this case?Please don't flame me. This is a question. When using a tube amps line out would that not constitute a load, or would you still need a dummy load?
 
#9
oleskool said:
When using a tube amps line out would that not constitute a load, or would you still need a dummy load?
Click to expand...
The line out is only coming from the preamp section, not the power section. It would work, but you wouldn't be getting whatever contribution the power section makes to the sound. You'd essentially have a tube pre / ss power, like many of the hybrid amps on the market.

To get the power section of the tube amp working, you need to connect it to a load, either a real speaker or a speaker siumlator / dummy load.

So if the question is "how do I get the sound of a 100 watt all tube amp, only louder" I'd say the options are:
1. Mic the cab into the PA, as someone suggested
2. Use two or more 100 watt all tube amps
3. Use a dummy load and run the output to an SS power amp
4. Use a modeling amp or software

True tube aficionados will say that option 4 isn't the same sound, but as far as I'm concerned it's close enough for live performace and it's a lot simpler.

My $.02
 
#10
oleskool said:
Very good thread. I have often seen threads on this board that state you can use use one amps out, to another amps pre amp in. Why is that not right in this case?Please don't flame me. This is a question. When using a tube amps line out would that not constitute a load, or would you still need a dummy load?
Click to expand...

The line out is before the amp output section (in most cases). Even in circuits where the "line out" is taped off of the output transformer it will not present a sufficient load for the output circuit. Line outs are 600 to 10,000 ohms and not the needed 8 ohm to 2 ohm load required.
While we are on the subject a dummy load is purely resistive, not reactive like a speaker. Hence the "dummy" part. The way a speaker interacts with the tube amps output is an important sound characteristic.
 
#11
Jim Nazium said:
The line out is only coming from the preamp section, not the power section. It would work, but you wouldn't be getting whatever contribution the power section makes to the sound. You'd essentially have a tube pre / ss power, like many of the hybrid amps on the market.

To get the power section of the tube amp working, you need to connect it to a load, either a real speaker or a speaker siumlator / dummy load.

So if the question is "how do I get the sound of a 100 watt all tube amp, only louder" I'd say the options are:
1. Mic the cab into the PA, as someone suggested
2. Use two or more 100 watt all tube amps
3. Use a dummy load and run the output to an SS power amp
4. Use a modeling amp or software

True tube aficionados will say that option 4 isn't the same sound, but as far as I'm concerned it's close enough for live performace and it's a lot simpler.

My $.02
Click to expand...

Would that be post poweramp? Not the same as a tube pre/SS power amp. Would you get that power amp sound?
 
#12
You could use something like this inbetween your tube amp and a small cab then take the signal out into a SS power amp and some big speaker systems.

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I've used this with my P.A. for my guitarists ultra boutique tube amp combo that doesn't have a signal out. It's much cleaner than a Mic and much easier to connect. It really works well and sounds amazing.
 
#14
B-Sring has a great point about resistive vs. reactive load and tone.

For something like this I would use as small of tube amp as I could and one speaker I really liked the sound of. Forget about volume and just get tone, then mic that and run mixer to poweramp to big rig. The tube amp and speaker would essentially be a "tone generator". At gig volumes its output would be pretty much insignificant. Could stack it with or set it beside the big rig to have access to its tone controls and mic placement, or even hide it behind the rig facing backwards or off sidestage somewhere like a sidefill for stage monitoring.

It's just like micing an amp for the PA. You're just using the big SS bass rig as a sort of personal PA sitting on stage. Could send the same signal to the big FOH PA as well.
 
#16
Being that a mixer is part of the setup, you could blend all that with a DI taken straight off the bass and use that to fill in cleanly the stuff under 100-200hz or so. Should sound pretty darn good.

I've messed with stuff like this using my Valve Jr., bass rig and PA system and it can indeed sound awesome. Haven't run like that at a gig though, already got enough stuff to keep track of with mixing the whole band. I would be inclined to do it though if I ever get into a situation where I don't have to mess with anything other than my own bass gear/tone.
 
#17
I did variations of this in the early 80's. First I ran my modified Fender Bassman into a dummy load I built, used a line out which was a signal padded down from the speaker out, and ran that into an EQ and SS power amp. Worked fine, but I wanted more.

So into my Bassman, I wired in a preamp out, and power amp in. I had a Peavey MK III and had wired in an adjustable aux in.

I ran the preamp of the Bassman into the Aux in on the PV. (The EQ also worked on the Aux)

I used the crossover in the PV, ran the high out to the power amp of the Bassman into 10" speakers (crossed at 300-500Hz) and ran the low end into the PV power amp (driving 15's and later 18's.)

Worked great. Oh for the great bi-amped days of the 80's.
 
#18
Isn't this what Van Halen did in the '70s?

Using an old plexi Marshall firing into a dummy load resistor instead of speakers. The dummy load had a voltage divider and that was used as a line-out. that signal was sent to a flanger, phaser, and echoplex, and then to a solid state H&H or Crown amplifier? There is so much legend, lore, and raw BS, bit I think this part is true.

Though, mic into a PA seems like a easy solution that is known to work.
 
#19
if you REALLY want the sound of your tube amp.. I've read that you can use a Tom Scholz Powersoak at its lowest levels to power headphones or direct into a board... which means you could use that output into a powerful transistor amp. My guess is that at those volumes you might be better off with an amp modeling preamp.. but this should work..

As long as the tube amp was within the power limits of the powersoak.
http://www.rockman.fr/Reviews/Power_Soak.htm
 
#20
KablesP said:
So could I put the SS power amp between the palmer and the cabinet? Or would I have to take the XLR out and put that into the SS amp and then into a cab?
Click to expand...

Let's back up a sec.
First, You can't run a power amp into another power amp, because you'll immediately blow up the input stage of the second amp. Input stages are designed to handle line level(small)signals only, not speaker level power.

Second, a tube amp, such as you're suggesting, MUST drive a load at all times or it will blow up. The load must be a speaker or a large resistor. Such resistors exist but only up to about 100 watt capacity, as far as I know.

Running the small tube amp into a large resistor and picking up the signal from the amp(at the speaker output) is possible. The Countryman 85 would work, for example. You could then take the signal from the Countryman and feed it to the larger, second amp.
HOWEVER not using an actual speaker does change the sound. It's not the same, because the resistor isn't a dynamic, reactive load like a speaker is. But it would work.

But is it worthwhile? Probably not, given the array of simulations and drive pedals and such available today.
 

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