Peavey Ultra 212 questions - mod or sell?

[tedmich]

mystery solved, this is undoubtedly the wrong amp for you, explore a Peavey Valveking or better yet Classic 50, or much of Fender's lineup.

[mushy]

I might as well have some fun with this thing while it's sitting here: https://app.box.com/s/wwfllal21shs5v1o34hk

[nashvillebill]

I understand your situation. I've got a Triumph 60 sitting here (the original version not the PAG). When I got it, it occasionally had volume dropouts, and also it was very noisy (hiss) at idle. I solved the volume dropouts by soldering all the connections between boards, but had only a little luck getting it to a point where it would idle more quietly--though on stage, nobody would ever notice that little bit of hiss, it just bugs me at home.

The sound though...well, cleans are OK. Not "stunning" but good enough. The overdrive channels aren't really what I'm after though: my choices are Crunch and Ultra. I don't play high-gain lead so the Ultra channel is basically useless for me. The Crunch channel is OK for "classic rock" power chords but it's not a great tone for blues or just-slightly-overdriven stuff. What I really wanted was something that would let me choose between a) a great clean tone, b) a slightly-overdriven blues tone, and c) a power chord crunch tone.

Could my Triumph be modified into such an amp? In theory, yes, but it's not practical; the Triumph has these stacked boards to try to compress all the stuff into as tight an area as possible. With the sockets on relatively flimsy PC boards and traces that are easily lifted, it's not a good platform for experimentation--and that was before I soldered all the connectors between the boards. (That solved the dropout issue but made it very difficult to service).

Maybe the best answer for me would be to build such an amp. If I only had more time and money...

[silverfox]

Upon further investigation and comfirmation from a post below, yes, they are noise gate diodes. Thanks for the correction.

Silverfox.

[silverfox]

Speaking of Guitar Center I have had some really good experiences recently selling used gear and the prices have come down on some decent stuff. I'm sure it depends on the demographics but you might give it a try if your going to sell the amp.

Silverfox.

[mushy]

What I really wanted was something that would let me choose between a) a great clean tone, b) a slightly-overdriven blues tone, and c) a power chord crunch tone.

That is pretty much what I need, too. Nothing fancy; just good basic clean'ish to crunch that can get loud enough for gigs. I'm wondering what a good circuit might be for the current transformers and speakers. Maybe something in the fender camp? I don't know that I would describe typical fender overdrive as 'crunch', though. Are there any 6L6 circuits that do crunch?

Maybe the best answer for me would be to build such an amp. If I only had more time and money...

I have it in the back of my mind that this amp already has the most expensive components for putting together something that I would enjoy playing: speakers, cab, transformers, tubes, and a few other usable bits. I could probably even use the old chassis, with a new face plate for the new controls. It seems very doable.

...now I'm pulling the chassis again to take a look at what kind of room is in there and what else might be usable.

[Enzo]

I don't look to the power tubes for crunch. Pretty much they are clean until you overdrive them, and if you are looking for an amp that is "loud enough" it doesn't sound like you want it cranked to the sky.

To me the Fender is the guitar amp, I don;t care for Marshalls. I like small PV tubers, not so much 5150. You sound really like a candidate for the common Fender with a pedal. I like the sound of the Hot Rod series amps, DeVille, Deluxe, but the dirt channel on them sounds like crap. I have yet to hear a Fender overdrive channel I thought was worth a second listen. But the clean channel sounds great to my ear. So plug a stomp box up front for overdrive, clean channel, good to go. One objection to that is they don;t want a pedal out there to trip over. But they want to have channel switching on the amp, which means... a stomp pedal for that anyway.


And that is consistent with my leaving the power amp alone and finding crunch in the preamp.

[mushy]

I don't look to the power tubes for crunch. Pretty much they are clean until you overdrive them, and if you are looking for an amp that is "loud enough" it doesn't sound like you want it cranked to the sky.

To me the Fender is the guitar amp, I don;t care for Marshalls. I like small PV tubers, not so much 5150. You sound really like a candidate for the common Fender with a pedal. I like the sound of the Hot Rod series amps, DeVille, Deluxe, but the dirt channel on them sounds like crap. I have yet to hear a Fender overdrive channel I thought was worth a second listen. But the clean channel sounds great to my ear. So plug a stomp box up front for overdrive, clean channel, good to go. One objection to that is they don;t want a pedal out there to trip over. But they want to have channel switching on the amp, which means... a stomp pedal for that anyway.


And that is consistent with my leaving the power amp alone and finding crunch in the preamp.

Enzo, I know exactly what you mean on Fender overdrive, but I think it is very dependent on how the amp is set up. I have played deluxes and twins that sounded like doo doo, and I have played others that were great. Of all of those amps, the overdrive has been on the mushy and darker side (no correlation with my screen name). Those amps aren't hard rock amps, imo. Rock n roll, blues, and country? Yes. Hard rock? Marshall, Hiwatt, etc.

If I were stuck with a single amp of my liking, it would probably be something in the Marshall or Hiwatt camp, although I love fender clean and dirty and reverb. But I like Marshall semi-clean, too. Hell, I like good sounding amps [not of the metal variety], period. I owned a Mesa dual rec when I was younger, and I never could get myself to like that thing, although everyone else loved it. I was phasing out of metal at that point, though, and I wanted the crunch channel on that thing to do some rock n roll, but it always sound/felt lifeless to me.

On Fender amps, the kid that I got this Ultra from had a Fender Prosonic. I had never heard one until that point. That thing had a somewhat bright, bitey, reedy kind of overdrive. It caught me by surprise. It wasn't an overdrive sound that I would want for a daily player, but as a semi-clean amp, it was very cool.

Would you by any chance happen to know the specs of the Ultra 60 output transformer? I'm measuring this thing with my dvom and not getting what I expect to see. The speaker side is reading 0.4, 0.5, 0.7 ohms.

Btw, I think that an overdrive in front of the clean channel, as it stands, would not be something I would like. The clean sounds very mid focused and hard, lacking both lower and higher frequencies, and it doesn't have any give. And it's too clean to begin with! I have an od pedal stashed around here somewhere. I'll have to pick up a battery and give it a go any way, just to see.

[Enzo]

Ultra 60 output transformer? Whatever it says om the rear panel and schematic is what I know.

Remember, your ohm meter measures resistance, not impedance. You are measuring the wire resistance in the winding. Transformers have no intrinsic impedance, they only have ratios. That 5600 ohms (or whatever) at the tube plates is only there if the rated secondary load is present. I would assume your OT has 4-8-16 ohm taps.

Btw, I think that an overdrive in front of the clean channel, as it stands, would not be something I would like. The clean sounds very mid focused and hard, lacking both lower and higher frequencies, and it doesn't have any give. And it's too clean to begin with!

Clean channel of what, your Ultra? I was thinking more like an OD pedal in front of the clean channel of a HotRod DeVille. Or HR Deluxe.

[mushy]

Ultra 60 output transformer? Whatever it says om the rear panel and schematic is what I know.

Remember, your ohm meter measures resistance, not impedance. You are measuring the wire resistance in the winding. Transformers have no intrinsic impedance, they only have ratios. That 5600 ohms (or whatever) at the tube plates is only there if the rated secondary load is present. I would assume your OT has 4-8-16 ohm taps.



Clean channel of what, your Ultra? I was thinking more like an OD pedal in front of the clean channel of a HotRod DeVille. Or HR Deluxe.

I have never measured an output transformer before, and I was expecting a higher resistance than what I'm seeing.

I caught what you meant, but it got me thinking of trying a pedal in front of the Ultra as is, which I did. It's a Danelectro overdrive. Not a great pedal, but it can sound ok. In front of the Ultra's clean channel, it sounds like one of those old solid-state Peavey Auditorium amps...pretty nasty and ugly. I saw that one coming, so no loss there. The pedal was better for the crunch channel with the channel set at lower gain, but it just sounded like the amp's overdrive with the gain up a bit. No surprise there, either.

[Enzo]

The speaker winding of an output transformer is by its nature a heavy wire and relatively few turns of it. You are measuring simple wire resistance. Most meters lack the resolution at low resistances to even read it.


To measure impedances, we usually apply an AC voltage to the secondary and see what comes out the primary. From that we can calculate the turns ratio and from that the impedance at the tubes for a given load.

[mushy]

The speaker winding of an output transformer is by its nature a heavy wire and relatively few turns of it. You are measuring simple wire resistance. Most meters lack the resolution at low resistances to even read it.

To measure impedances, we usually apply an AC voltage to the secondary and see what comes out the primary. From that we can calculate the turns ratio and from that the impedance at the tubes for a given load.

Thanks for the info, Enzo. I remember reading about that, now. I think it was 1V for ease of calculation, but I assume that 9-12V from an old wall wart should be fine, too, with a little more calculation. Am I guessing right that the number of turns, as opposed to the ratio, is to do with current handling?

Obviously, my understanding of electronics and how amps work is shallow. I'm currently reviewing circuit basics from an old book, while also rewatching a video series by Uncle Doug on how tube amps work. I had a few electronics classes a couple of years back, but the classes exstinguished my interests in electronics for a while. There was too much unnecessary busy work and worrying about grades for much of any practical application and hands on experience. I'm guessing that you're a tech or ee?

[Enzo]

A wall wart is fine, but remember it will load down, so what matters is the actual voltage present, not the rated voltage.


Or just get the schematic from PV, the winding wires are listed.


Yes, I operate a pro audio repair shop. I have been in electronics for 60 years. In rock and roll for 45 years, at the shop 28 years. I almost have it figured out.

[mushy]

A wall wart is fine, but remember it will load down, so what matters is the actual voltage present, not the rated voltage.


Or just get the schematic from PV, the winding wires are listed.


Yes, I operate a pro audio repair shop. I have been in electronics for 60 years. In rock and roll for 45 years, at the shop 28 years. I almost have it figured out.

I'm looking for the voltage under load, then?

Hey, I have something to look forward to when I get old: Fixin' amps for punks...Here's your amp.

Now get off my lawn! Seriously though, thanks for helping us punks out.

[g1]

Here's your amp.
Now get off my lawn!

That's funny, I'm thinkin' Gran Torino. Oddly, it was set in Michigan, just like Enzo.