Peavey Triumph 60 Head

[plexi50]

I picked this Peavey Triumph 60 head yesterday for cheap. I did the mod to allow the EQ to function in the Crunch and Ultra channels. Also shorted C1 & C2 diodes to remove the premature clipping in the preamp. Amp is much more open now and sounds pretty decent. The clean channel is very good i think.  Reverb is smooth and not overbearing. Question:

How can i determine if the PT in this amplifier can handel EL34 power tubes? I have no PT spec's

[phsyconoodler]

You could put some in after you modify the socket wiring,and check the before and after heater voltages.If they drop too much then the PT is being taxed too much on the heater winding.
  It may have a stout PT in it but I would leave nothing to chance.

[birt]

if you really want you can always add a small heater transformer in about 10 minutes

[plexi50]

Both good ideas. I will work with it tommorrow. I just love EL34's.

[phsyconoodler]

Bet they won't sound a whole lot different than the 6L6's in that amp.

[plexi50]

You are probably right. I may just leave well enough alone. It sounds decent now
Im wondering if adding a 5 henry choke in place of the resistor might smooth out the tone of the crunch and ultra gain channels a little better?

[Jack1962]

I have one of this myself and have done those mods as well , mine sounds pretty good too , however , if you add the choke let us know how it works out.

                                                        
                                                               Rock On

[plexi50]

The changes i just made really make this amp a jewel to keep

The Fuzz / Buzz is gone and the amps Crunch and Ultra channels have a very nice and smooth growl to them

Each channel as well is totally different sounding than the other. Before the changes both the C & U channels sounded almost identical with no noticable difference between them so to speak

I changed the 220K 12AT7 plate from 220K to 100K. I changed the plate of V1B from 150K to 100K. V1A stayed the same at 150K

I changed the PI to the standard Mashall / Fender LT PI using .022 coupling caps

I used a  Classic Tone 5 henry choke in place of the 400 ohm resistor / What a huge diff in overdrive quality

The grid bias resistor was 68K and now is 27K. The grid is -51.00 VDC / It calls for -56 VDC but it sound good enough to me

The Clean channel is very excellent as it was before making any changes / My job is done. It really has character and is a smoothie

Im finding that Classic Tone transformers are pretty darn good sounding and look well made / There prices are dirt cheap

This is the 4th  transformer i have used from them. A JCM 800,Peavey Delta Blues,Mig 60 and now this choke from them





 

[Jack1962]

that's great what power tubes are you using , I'm using Ruby's

                                                    Rock On

[plexi50]

I am using a pair of Sovtek 6L6GWB tubes for now. The amp board did not follow the schematic 100%. There were many different resistor values other than what shows on the schematic. They are factory installed /

I changed some more parts:

I removed C7 .015, Removed and bussed R9. Changed R6 100K slope to 33K. Changed V2B from .47 to .68

It continues to get better. These are the final touches. I am using EL34 power tubes now

I can hear a more hollow and woody tone using them over the Sovtek 5881/6L6GWGC tubes

I am pleased with the results so far. Much better than stock

Just changed R86 V2B grid divider from 220K to 470K. Even smoother now. Compression is  insane but smoother and well defined

If you make any changes to this amplifier be sure to use the schematic. The preamp tubes are scattered throughout the amp and not wired as you might think starting with V1A on down the line

In other words each tube has two halves to it but they are not wired parallel to one another or even operating the same channel

  

[gmoon]

plexi50, I'm reading about your mods with great interest. I picked up a Triumph 60 a week ago (combo version), mainly 'cause I enjoy it's younger brother (Peavey Bravo head conversion).

This one already has the tone stack and diode-bypass mods. Speaker was replaced with a Patriot "Texas Heat" speaker.

You're right on about this amp and humbuckers. The guitar I've owned the longest is a Les Paul from my high school days (had to good sense to hold on to it), and although I almost never play it, it really sounds great with the Triumph / TH speaker. Really fat middle, fairly bright overtones but not brittle. Tons of overdrive and a nice clean channel, too. Although the TH speaker is not quite my taste with single coils (but those sound good with a 2X12 cab).

Only problem so far is the reverb didn't work. Subing the V3 tube fixed it initially, but would randomly fail, and sometimes the whole amp would cut-out. If I'm reading the schematic correctly I don't understand how a bad V3 would kill all the channels--it's the reverb recovery and second stage of the clean channel. Unless the schematic is off on labeling tube pairs... (?)

Anyways--no matter. It quickly became apparent that the V3 pin sockets were WAY loose, so after a little attention the amp is fully functional now. Haven't run it for more than 30 minutes at a time yet, though.

One more mod done by the last owner--apparently the OT has a 16 ohm tap that's unused on the combo but not the head. An additional jack was added for a 16 ohm load (the Texas Heat is a 16).

OK, techie question time--
What's the deal with V2A on the crunch/ultra channel? It looks like a normal inverting gain stage, but the plate resistor is a voltage divider, and a large ratio to boot (1:10, 10K : 100K). I've never seen this before...

[gmoon]

Yeah, now the clean channel & reverb works well, but the crunch/ultra cuts out. Should have expected it...

Opened 'er up, and there's some of the worst soldering I've ever seen. Lots of modding and "repair" on it. New switchcraft-type jacks, so that's a plus.



Ah, well. One thing--the preamp tubes are difficult to access, as is the tube cover that PV uses to secure the tubes. Good idea in theory, but if both the tubes and the cover are crooked when it's screwed on, it would seriously stress the sockets.

Here's a pic of the last crunch/ultra gain stage with the plate resistor as a divider. If anyone can enlighten me, I'd appreciate it.

[plexi50]

The clean channel is amazingly very nice. The Crunch and Ultra channels need some work. If i remember right they are using 50K pots which are bringing the volume in way to fast and is overly sensative trying to get the OD channel dialed in. Looking back it does not sound as good as the Bravo though but pretty close. Close has never been enough for me so i spin my wheels trying to figure out why some amplifiers with a pretty much identical preamp can sound so different. The OT is the part in an amp that makes the biggest differences to me.  I will look for my Triumph folder and see what all i did and post it

[gmoon]

Thanks, Plexi50. If you get the chance, any info is mucho appreciated. I know for sure I need to reflow some solder joints...

I do agree about the Bravo. Great little amp!

[plexi50]

One fast thing i found out about one Triumph i worked on. It had bad preamp sockets period and all the solder in the world would not fix them. Some times a socket is just better off being replaced

[gmoon]

Yeah.  The current sockets are ceramic, and I suspect they were already swapped out. And should be again.

[eleventeen]

That's some seriously bad soldering you got there. Easily fixed, however. You'll need to jumper one or more of those connections as it appears that foils/traces have separated from the board in places. To me, tube sockets on PC boards are somewhat problematical, concept wise. Not that they can't or won't work, and I have no great prejudice against PC board construction in general, except where relatively high-mass items (like tubes) get plugged into the board repeatedly.

[gmoon]

It's sitting on the bench, waiting for me and my iron.

The amp hasn't cut-out since I removed the chassis, set it upside down (tubes up, like the head) and removed the preamp tube cover.

I'm thinking the Triumph is probably why Peavey went with the whole PAG (parallel axis geometry) thing.... Unlike this one, the PAG amps have easy access to the tubes. In all honesty that seems to work well in the Bravo-- the tube PCB is separate, and has only a few additional components. Of course, PV eventually dropped PAG in favor of a traditional layout, which works OK for everyone else if it's designed well (with the usual caveats about PC boards in tube amps, of course).

I've noticed with this design that the preamp tube cover presses down on both the tube/socket AND the PCB...while in a typical shielded socket, the spring pushes the tube into the socket, but doesn't exert any pressure on the circuit board. If it needs new sockets I'll see if the shielded type fit, and ditch the cover.

[plexi50]

Here are some pics i dug out. Definatley short CR1 & CR2 clipping diodes

[gmoon]

Cool, that will help for sure.

Earlier today I removed the solder, cleaned and resoldered two of the tube sockets. Unfortunately there are 5 partial pads on the one (pictured in the previous post). I did what I could, but might have to wire those pins to the traces instead.

It's a long shot, but I know they make small PCB eyelets for this type of repair.

The gain channel is cutting out again, but there are some weird associated symptoms--when it cuts out, stomping the switch repeatedly will sometimes awake the channel, plus the switching gets noisy (thump) with the channel cutting in/out. That might be an issue with the relays...or maybe the molex connectors that lead to the control board, since the relays are located there.

Thanks again, plexi50.

[tricky]

I realize I'm years late to this topic, but I have just procured a triumph 60 head and am considering some mods. I wanted to ask plexi50 about the values of the plate resistors in the pre-amp - you say "I changed the 220K 12AT7 plate from 220K to 100K. I changed the plate of V1B from 150K to 100K. V1A stayed the same at 150K" and then later on refer to many of the resister values being out of line with the schematic ("The amp board did not follow the schematic 100%"). From the schematic I see, the plate resisters for V1A, V2B, and V2A are all supposed to be 100k from the factory (R20, R21, and R23). Am I reading the schematic wrong, or is the production amp that much different from the published schematic?

Thanks!

Patrick

[alerich]

I bought a Peavey Triumph 120 combo for cheap ($125) on Craigslist as a fun mod platform. These are the mods I ended up doing. Some I got here at Hoffman from people, others on other forums and a few I came up with myself. I can't honestly recall what each mod did - I'd have to go back and look at the schematic. Made the amp a bit more Marshallesque on the overdrive side and a lot less Peaveyeqsue. Didn't impact the clean channel. After I finished the mods I gave it to my girlfriend's son. Oh, the amp had a quad of Sylvania 6L6GC STR 387 power tubes in it when I bought it. Schawing! A duet of those now resides in my Soldano Hot Rod 50 and the other set are sandbagged for spares.

Peavey Triumph 120 mods:

EQ Mod: remove jumper between relay and C62/R11 junction.
Remove R11/C62 (ground path at top of tone stack).
Diode Mod: Remove CR1 and CR2 and replace them with a jumper.
Remove C17 between diodes CR1/CR2 (removed above) and ground.
Remove R5 150K and replace with 100K. V1B (first stage) plate resistor.
Remove C7 (top of mid control to wiper of mid control).
Remove R9 10K and replace with jumper.
Remove Normal bright cap 470pf and replace with 120pf.
Install 65pf "always on" cap across bright switch.
Remove C14 22uf cathode bypass cap and replace with 4.7uf (V1A cathode Crunch/Ultra first stage).
Bypass R36 1M with a 10pf cap. Install switchable 1M in parallel with R36 - gain boost.
Remove R39 220K and replace with 100K (V4A plate resistor).
Remove Hum Balance control. Install 100 ohm resistors off each heater leg to ground.
Install 1 ohm 1W precision resistors in pin 8 of power tubes. Connect Pin 1 to Pin 8 on power tubes in case I ever want to install a duet of EL34s.
Mod bias circuit for fully adjustable bias.
Remove preamp out wire and attach 16ohm OT tap to same.
Disconnect line out.

[eleventeen]

I have seen these amps for sale cheap ($125 is darn good!) and under $200 or so, they are awesome sources for plenty of parts. I saw one for $160 a few months ago, and I probably would have bought it except it was 150 miles away (and gas was > $4 then!) and it was in a store so sales tax would apply. It was still a very decent deal.

[alerich]

With the stock circuit these amps sound pretty honky. The OD channel reminded me of a saxophone. The open back combo format with a 150 watt Peavey Scorpion didn't help matters. After I finished modding it (and it was fairly easy to work on for a Peavey) the tone opened up and it really sounded pretty nice - particularly into a nice closed back 4x12. My 5150 was the same way. A good amp stock that came to life with only a handful of small tweaks.