Got a Peavey Classic 50. Can I use trannies for 36w conv?

[Gr8Scott]

I've got a peavy classic 2x12 that I like but don't love. It sounds like poop next to my boutique JTM-45. I can either mod the existing platform to better suit my tastes or I can scrap most of it and use the nice enclosure and trannies to make something better. I can't seem to off the amp even though I consider my price to be quite low. Can I use the trannies for this amp to make a 36w with a half power switch? It's got a reverb tank on it, so that might not be a bad thing to use also. I don't have to use the reverb, because it adds complexity though.

[krash]

that's an SS-driven reverb right? If so, then you prob. can't use it with a tube-drive reverb (presuming that's what you'd want in a boutique-ish or custom amp). impedance is all wrong.

Classic 50 is 6L6's, I think the B+ is probably way too high for EL84s but maybe you could work out a 36-ish-watt design with it using 2xEL34s in the power section instead of the EL84s like a 36W. It would sound very different from a EL84 36W.

[Dynaflow_Donnie]

You should be able to tame the B+ voltages enough to use it, use some Zeners or resistors to get enough of a drop to where you need it. The 50 watt OT probably should be ok too, I think Richie said that Nik at Ceriatone uses what looks like a 50 watt OT. I'm planning on probably doing likewise with a crate stealth 50 watt head, it uses 4 6v6's and about 4 preamp tubes I believe. I'd sell it, but I couldn't even buy the iron, head cabinet and chassis for what I could get from it. Its got the same issue for a 50 watt head it's real weak unless your using the higher gain side which isn't what I do.
Anyway, sure, what you got to lose. Only deal is you may have to use solid state rectification now that I think about it as it probably doesn't have rectifier taps on it, not a huge issue, just zeners and stuff like I mentioned. Good luck with it.

Regards,

Dyna

Ps: He may be right on the reverb, maybe the tank, but its impedence is probably not right, but hey its a good excuse to build a stand alone fender reverb with a 6k6, its one of the best anyway IMHO.

[Gr8Scott]

Nope. This classic 50 has 4 EL-84's. I don't know how they are supposed to be generating 50 watts (they sure don't sound like 50 watts as my Sovtek Mig 50 and JTM-45 are both way louder). I know the power tranny will work with 4 EL-84's, but will I be able to make something that sounds like a good 36w amp?

The Classic-50 lacks output stage distortion and balls. I can mod in a bit more balls, but output stage distortion isn't going to happen with this design. I'd like to have a bright channel that is like my JTM-45 and a severly dirty plexi type channel for my humbuckers.

This amp currently pushes three 12AX7's and four EL-84's. What can I do with this configuration? Can I have tube reverb? The reverb is solid state currently, but I can rewire it with help. Or can I hard wire in a couple more gain stages for channel 2 for an insane distortion on that channel? Or could I do an additional gain stage and additional tone stack for channel 2? I've got a schematic for my version of the classic 50 for anyone who wants to view it. It's from blueguitar.com.

I know that I'd need a whole new board, new sockets, new pots, new caps/resisters and a new custom bent chassis (no problem as I have access to a brake, wire welder and a plasma cutter at work). What else will I need?

You folks are phenominal here and all the help you give is greatly appreciated.

[Dynaflow_Donnie]

I'm envious of those tools at work. When I was a welder I had access to that sort of thing, sure would have made things nice now. Plasma cutters rock, that was one of my favorite gadgets in the shop, we used plywood for templates, some plate and bam, its a done deal. Thats cool!

Regards,

Dyna

Ps: Others will chime in I'm sure, I'd try that output tranny, but if it doesn't give the 'good housekeeping seal of approval' 36 watt sound, you could always just get the 36 watt output tranny, be a few dollars, but it sounds like you won't have alot into it anyway in the grand scheme of things.

[Gr8Scott]

Did a bit of research. I understand that I was mistaken about the tube config on the 36w. Can't have extras. I can do a more or less normal build except for the SS rect. This simplifies things at least.

[krash]

something is not right. I have a Classic 30 and it definitely keeps up (for volume) with my 18W, but it would probably not be in the hunt with a JTM45. I would say the C30 sounds pretty danged good all things considered, especially considering the price. The only thing it really needed were decent preamp tubes and a good speaker.

I have gigged a lot with my C30 and it's probably still my main gig amp altho I plan to rebuild it "one of these days".

[Gr8Scott]

My main gripes about the classic 50 is the lack of output tube distortion and the tendancy to not work well with pedals. If this is something that can be corrected via mods to the existing amp, I'm all ears. If not, I would prefer to scrap the guts and part the boards/chassis out on ebay after I get the newly configured board ready to install.

[rjgtr]

I think the Classic 50 is a different animal than the Classic 30. The CLassic 30 was a really good day at Peavey R&D. The power amp is more like an AC30 or 36 watter. The Classic 50 is fixed biased (and like a lot of Peaveys too optimistic on output - 40 is probably closer) and while that's not bad, I think they were trying to get max power from it. Unfortunately, too much plate voltage in a fixed biased arrangement can make an amp really sterile (think late 70s SF Fenders).

You could probably use the transformers for a new build, even a 36 watt. You'd need to check the specs and make sure they fall in line. You might also need to tame the B+ a little to get the amp to breath more.

[johnnypig]

I hated my classic 50 so I very hapily junked everything but the trannies and a few electrolytics. Just don't use the PT for an 18w like I did at first, cos you'll get 420VDC on the plates for lack of current draw.

I think the OT sounds horrid and at some point it'll get replaced or used to experiment with learning how to wind my own. With 4 el84's it's ok, but once you get the volume up at aound 5 or 6 the OT is basically saturated beyond use (for anything wanting headroom that is) and it's a pretty nasty bite even for el84's. Like a bee's nest. Not just with the 18w circuit, but with a number of preamp circuits like JCM800, vox etc.

Here's someone else who reused a classic 50 (el84) : http://maza.fi/gear.php

I hope you have fun and don't cut up your fingers too bad!

-jp

p.s. drilling the chassis for new sockets is wicked painful! That thing is THICK... I settled on a metal use hole-saw and clean up with a dremel. I don't think punches would work at all.

[allynmey]

Same advice I gave today of a classic 30. Sell it. There are many people that will give you about $400 for it. Buy the proper parts to make a 36 watt. If you have trouble with the amp made with peavey parts or some sort of frankenstein amp therein, it is harder to diagnose and get info on the part. Peavey will not be sending you a wiring diagram or impedance chart if you use their trannys! Sell them and buy a heyboer!

Allynmey

[Gr8Scott]

Maybe I should just fleabay the whole affair. This would free up some cash for this venture and get an 18w project off the ground. I don't need a 36w amp really anyway. I really need an 18 watter. If you have a JTM-45, you don't really need a 36 watt clone of one. Maybe I'll do that and just make an 18 watt TMB or sIII. I'm mainly looking for a lower wattage clone of the JTM-45 that will allow me to practice at less than ear splitting volumes. If I could make a 5 watt version that has the same tone, I'd be all over that. By having a clone of the JMT-45, I could use all the same pedals at all the same settings. Consistancy in this respect isn't necessarily a bad thing, but it would also be nice to have something with a little variety to it.

[krash]

I think I'm the guy you gave that advice to...

And I think I'm going to take it.

I really like the form-factor of the C30 but probably would get enough money for the whole shootin' match on ebay to finance another cabinet, chassis and transformers, or at least come close. I may even have other transformers kicking around that would do the job, make it much easier!

now off to find a cheap cabinet

[ZOEnIain]

Same advice I gave today of a classic 30. Sell it. There are many people that will give you about $400 for it. Buy the proper parts to make a 36 watt. If you have trouble with the amp made with peavey parts or some sort of frankenstein amp therein, it is harder to diagnose and get info on the part. Peavey will not be sending you a wiring diagram or impedance chart if you use their trannys! Sell them and buy a heyboer!

Allynmey

Actually, Peavey will fall over themselves to help you out with technical information. I've rung their UK tech department a bunch of times and they'll happily Email me PDFs of anything I want, except for brand new models. Anything over 2 years old seems to be fine.

Possibly Peavey US are less accomodating but the UK brnach are super helpful.

[krash]

well I'm still going back and forth... I could probably get 4 bills for the C30 and that's enough for a chassis, transformers & parts to build a cab, but I still would want a different chassis layout and the C30 cabinet is just really ideally-sized for a "gig" amp for a guy with a Miata.

So I think for now, I'm going to stick with the C30 chassis & cab for my sleeper 36W.