All-Tube Power Amp? (sans pre-amp)

[lowend1]

Depends on what you need and how much you want to spend. If I had to choose a hybrid, I'd want the tubes in the preamp, because thats where most of your tone shaping happens. In a guitar amp, the power tubes are more crucial than in a bass application, IMHO.

 

[john b carvalho]

I second on what RC said,Mesa Boogie M-180 or Strategy 400/500.Hard to find either,but they do come up once in awhile.

John

 

[JPMcGuire]

I have tried just about all options and ended up with the following over this 10 year process which I have and use today:

1). 76 Ampeg V4B with 6550's. It has "the tone" at a suprising volume for 120 watts or so. I actually prefer this head to my 71 SVT Blueline I just sold.
2). Aguilar DB750 - a true cross bread between an svt and a solid state head IMO. Lot's of girth to this head.
3). Little Mark III - great little head for convience, practices, small gigs.

There is definately a difference in all tube for the feel when you play to the tone. No SS I have ever played can copy it.... Save up and get both

 

[Gatortail1]

I've got a Peavey Classic 400 that's pretty bad a$$, but I've been using an old Acoustic most of the time. Anyone interested in a Peavey?

 

[mikeswals]

You simply need more output in the heads department. Simul295 not nearly enough. If that's the route you're trying to do, then the Strategy 400 or 500 is the way to go.

 

[77PBass]

Usually the purpose of a power amp is to make louder what you have. I won't deny that there are probably specialized ones out there with their own characteristics. (I'm looking at stuff like the SVT power amp which was just the rack mounted output section of an SVT IIRC.)

Huh?

You want SVT tone? You need the SVT pre and power circuits to achieve it. The choice of power tubes is an integral part of a tube amps sound. Some power sections are designed for minimal distortion while others happily distort and sag (compress) and do magical things.

On another note....try and find an old Dynaco Stereo 70 power amp. These can be run in mono and sound awesome. I run a SVP-CL into a Dynakit Stereo 70 ( the version you had to put together yourself) and it sounds great.

http://cgi.ebay.com/Vintage-DYNACO-...ctronics_R2&hash=item3f07d319ac#ht_889wt_1141

 

[Mr. Foxen]

The term 'Slave' was used a lot to describe valve power amps, if you are looking vintage, that is the term to use.

Also, the Mesa Strategy is another valve power amp, I think there are a few power options, I have a 400 spare.

 

[Bassman822]

There is always the McIntosh MC3500. However, IF you can find one, it will run you 20 to 30 BIG ones

 

[m.oreilly]

i'm using one of those peavey classic (60 watts) tube power amps between my pre and ss power amp. with the input of the peavey on full, the direct out just barely up, i'm getting a giant thick tight warm completely controllable sound i have never experienced. now i just need a dummy load on the speaker out of the classic.

 

[pablomigraine]

That's funny, most people say that it's the power tubes that give you that tube tone.

I too scratch my head at this.......

 

[77PBass]

I too scratch my head at this.......

Why do Class A power sections sound different than Class AB? Why does a power circuit with a negative feedback loop sound different than one without? Why do KT88's sound different than 6550's?

 

[m.oreilly]

with all the chest pounding re tubes, i confess i would never want to use/depend on a tube anything. clunky unreliable lead sled expensive over the top...loves me some overdriven warm tube OD though...

 

[Korladis]

I still think that if someone wants a tube power amp, they may as well just buy a tube head and bypass the preamp. They're the same size and weight, or close enough, anyway.

 

[Calaverasgrande]

with all the chest pounding re tubes, i confess i would never want to use/depend on a tube anything. clunky unreliable lead sled expensive over the top...loves me some overdriven warm tube OD though...

I have never experienced less reliability from tbe heads. I have experienced less mobility. Those things are heavy! I've broken a toe and a thumb from my heavy tube heads.
But as far as reliability, every show stopping problem I have had with my tube heads was always been user error. Pluggin in the wrong loads, or not pluggin in a load. Solid state heads I simply blew the hell up. Acoustic POOOF! GK , POOF! Ampeg mega ka-POOOF!
Not that tube heads dont blow up, but niether are they inherently unreliable.

 

[77PBass]

with all the chest pounding re tubes, i confess i would never want to use/depend on a tube anything. clunky unreliable lead sled expensive over the top...loves me some overdriven warm tube OD though...

Some people like a Mazda Miata...some people like a 1970 Ford Mustang Boss 302....different strokes for different folks.

I am thankful that there is so much choice, and after many years of the same-old same-old, manufacturers are bringing us new technologies (tube pre's hooked to class D power amps) and old technologies reimagined (orange isobaric cabs with neo speakers)

 

[coreyfyfe]

Where is this picture from? Early promo? It just struck me that there are top handles on that SVT. I'm not sure what would be worse, those or the side handles that they came with...

 

[bobcruz]

Mesa makes/made a few, peavey, I think carvin makes one, and then there's always the aguilar DB728...

Carvin TS100--excellent stereo power amp with 50 watts per side, bridgeable to 100 watts into 8 ohms: Invalid Link Removed

 

[seamonkey]

There's just no market for high powered all tube power amps is there?

 

[Bassman12350]

Why do Class A power sections sound different than Class AB? Why does a power circuit with a negative feedback loop sound different than one without? Why do KT88's sound different than 6550's?

Class A power amps are biased so the output stages are always at full current operation. That means an amp like an SVT would be drawing full load current as if it were putting out it's full rated 300 watts RMS all the time. That would make it very expensive to run. Additionally class A amps are more expensive to design than class AB push-pull amps. As a general rule, no bias in the output circuitry runs a set of output tubes harder, produces more gain, and can give an "edgy" or slightly distorted tone at higher volumes. Circuits providing negative bias tend to be cleaner sounding, have less gain, ( though the preamps can get that for you) and drive the output tubes less hard. Last but not least a 6550 and KT88 tube are exactly the same. The 6550 is the "industrial" equivalent of the KT88. Hope this explanation helps.

 

[tombowlus]

In addition to options from Mesa, Ampeg, Peavey, & Carvin, there is also the (discontinued) Aguilar DB728, and the (still available) Demeter VTHF-300M.

Tom.