Tube power amp

James Quackenbush · Post by **James Quackenbush** » 28 May 2016 3:04 am

I know a lot of you guys are concerned with the weight of your gear since we're not getting any younger ...You could always go with a tube preamp, and a solid state power amp ....This combination would save weight , and still give you a decent tube tone ...The solid state power amps today are light in weight , and can give you a LOT of power for the $$ ....Jim

admin · Post by **b0b** » 28 May 2016 7:16 am

Mark Wayne wrote:I'm new to the tones of a tube amp. What are some adjectives in general used to describe the tone in comparison to the solid state, Nashville 400's? Warmer? Thicker? More shrill? Peakier? Woofie? Etc.

It's not tone, it's dynamics. At low volumes there isn't much difference. As a tube amp approached its rated power, a natural compression sets in. You hear it in Lloyd Green's playing, as a prime example. The peaks on the attacks are softened. You can feel this effect when you play through a tube amp at stage volume. The adjectives I would use are "organic" and "natural".

admin · Post by **b0b** » 28 May 2016 7:30 am

Paul Sutherland wrote:As a follow-up question: Can anybody post a schematic of a Twin Reverb style power stage; only show the power amp; specifically leave off the preamp, reverb and tremolo wiring. I'd like to see how simple or complex it would be. Maybe I could show it around and have someone build just that.

Here's the complete schematic:

The parts you need are the power supply at the bottom (see "AC Receptacle" and follow it through the transformer), the 12AT7 and the four 6L6GC tubes.

Brooks Montgomery · Post by **Brooks Montgomery** » 28 May 2016 8:42 am

James Quackenbush wrote:I know a lot of you guys are concerned with the weight of your gear since we're not getting any younger ...You could always go with a tube preamp, and a solid state power amp ....This combination would save weight , and still give you a decent tube tone ...The solid state power amps today are light in weight , and can give you a LOT of power for the $$ ....Jim

Are you aware of any A - B comparison sound clips or youtubes that might show what a tube pre-amp can do for improving the tone of a SS amp? I'm very interested (I posted awhile back about my Old Gibson SS amp), but can't find any compelling examples--before I drop some $$ cheddar on one more box or pedal.

Mark Wayne · Post by **Mark Wayne** » 28 May 2016 9:46 am

Very interesting guys. Would an power attenuator (i.e. Rocktron) in the speaker path be appropriate for playing in low volume venues like supper clubs, etc., to bring out the tube "naturalness"?

Jonathan Mitguard · Post by **Jonathan Mitguard** » 28 May 2016 10:00 am

This is a great topic as I have been interested in the same thing. I've been using a Peavey Classic 50/50 with EL84s and it is pretty nice Bridge-able to 100w. It is heavy. The other issue with the rack mounted power amps is the cooling fan. Typically not a problem live but in a studio it needs isolation. So I'd love the possibility of a 80-100w tube amp without a fan to place in or near the speaker cabinet. I'm using a stereo steel pre now but seriously considering a Octal V-8.

Paul Sutherland · Post by **Paul Sutherland** » 28 May 2016 10:38 am

I was very surprised to see this thread has come back to life.

The Peavey Classic 60 power amp that I bought sounds wonderful with the Sarno V8 preamp. I have the amp in an SKB 4 unit rack case. The amp takes only 3 spaces so there is open space above the tubes. I use the amp with the metal top removed from the amp, so there is ample open space to dissipate the heat of the tubes. I disconnected the amp fan so it's very quiet. The fan certainly would not be an issue at stage volumes, but for playing at home or recording it is noticeable. If a Fender style amp doesn't need a fan, I don't see why this amp needs one, particularly since the tubes on this amp face up so the heat naturally rises up and away from the amp.

The sound quality of this Sarno/Peavey rig is on par with my 1970 Twin Reverb and my Milkman Mini. I would describe it as buttery and smooth, like fine milk chocolate.

I have used the Sarno with a solid state power amp, a Matrix GM50, and it sounds very good, but it's different. The power amp definitely makes a difference. I prefer the tube power amp.

James Quackenbush · Post by **James Quackenbush** » 28 May 2016 11:36 am

Bruoks ,
It's hard to tell you comparisons , because as b0b said , there is a natural compression that goes on at gig volumes .....It's all part of the feel and tone of a good tube amp ...AND they are all different in how they behave and the tone they produce ....You would really have to go out and check out the various offerings to see what you like ... You might not like the same amp that I like .... When the harmonics kick in, and the compression helps your notes sustain longer , and the general richness in tone comes into play , you will know you are there ... It's more something that you would have to experience than to have anyone trying to explain it to you ... Which is better ? ...To sky dive out of a plane , or to go 160 mph on a motorcycle ? ....... Jim

Mark Wayne · Post by **Mark Wayne** » 29 May 2016 5:28 pm

b0b wrote: I still use the 20/20 now and then.

Bob, Do you have an additional preamp for eq'ing then?