Amp Circuit Types?? What is a Peavey Classic 50 based on?

[BPSUL]

So I am 106 pages into the "eminence speaker" monstrosity of a thread and I keep reading over and over about such and such speaker will sound good on amps with fender type circuits or on marshall type circuits or vox type circuits....

So what type of circuit is a peavey classic 50?

Im talking about the modern classic 50 - the one that comes in 2x12 or 4x10 not the 70's model "Peavey Classic" that is a hybrid design.

Can someone clear this up for me? I believe I have read that the Classic 30/50s are based off the Vox AC30 design. Is this true?

This knowledge would maybe help me interpret the huge eminence speaker thread. Thanks in advance...

[phsyconoodler]

I think there are some similarities to a vox but it stops at 4-EL84's.They don't sound anything alike and the Peavey has all kinds of typical peavey stuff like pre and post gain structures,reverb and it's fixed bias.It runs the power tubes at high voltage and throttles back on the current so they live.An AC30 is cathode biased.
Really,the only thing it shares with the AC30 is it's 4-EL84 power tubes.
Not a bad sounding amp,but it cooks the tubes,has undersized transformers,uses DC heaters and is a circuit board nightmare.

[BPSUL]

Not a bad sounding amp,but it cooks the tubes,has undersized transformers,uses DC heaters and is a circuit board nightmare.



Thanks for the info.

The quote above sparks 3 questions:

Cooks the tubes? Which ones specifically? Preamp tubes, I assume? Anything I can do to minimize this?

Undersized Transformers - does this mean that a transformer upgrade could be a good "bang for the buck" upgrade?

Circuit board nightmare: This makes it hard to mod, I guess? The blue guitar page has lots of common classic 50 mods and I was thinking of trying one myself (the simple one that puts the lows back into the drive "channel") would I be better off taking this to an experienced tech? My experience is limited to building pedals (and yes I know all about draining the caps)


Thanks for your info.
Brian...

[phsyconoodler]

They have a fan in these amps which is a nice touch.The power tubes are the ones that get hot.
I would not suggest modding these amps unless you are well versed in tube amps and PC boards.You could ened up with a pile of worthless PC boards.
If you have very detailed instructions and are very careful with your soldering iron and have a solder sucker or wick,you can do the mods.The schematics are hard to read and not easy for the average joe to decipher.

[Gatorman352]

Most people who mod / build amps start with amp kits because I it is usually PTP construction with clear instructions and visual layouts. I would suggest building a kit first to build your confidence then move to building amps without a kit getting support from a forum like 18 watt.com. I would build a simple fender circuit or marshall 18 watt TMB before you attempt say a SLOCOLONE. Then I would look into moding your main amps that have PCBs. You will find that tube amps are simply devices. The real talent lies in designing unique circuits. Good luck if you take the plunge it can get additive.