Peavey Triumph 60

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Hello All!

I procured a Peavey Tube amp head about two weeks ago. I have been experimenting with adjustments, tried a different set of 6L6GC (Currently has 6L6GCW's from Tube Depot with original Peavey brand 12AX7's and a12AT7)

I read last night on a post that you can take one of the power tubes out and it won't hurt anything. I am curious if this is true. I don't want to do something stupid and cause myself some heartache.
It makes sense to me because if one of the power tube is missing, there is no potential for current. But then again if there is current needing a place to go because the system is designed to need both tube, then I could see this being a problem too. Can someone clarify please?

Also:
This amp has MAJOR overdrive. Even with the drive backed off so far that the volume drops off to nothing, the overdrive is too much. I was doing some reading on the eurotube.com site and they have a retube kit that will drop the over drive by about 40%. I am wondering if someone here has done something like this? I would really like to drop back on the overdrive and work towards something more usable: something well below the "Head Banger" mode this amp seems to be stuck in.

I have read about a couple of mods that are supposed to make a nice difference in this amp. 1 mod makes it so you have tone control on the drive channels. This mod was already done. The second mod is bypassing CR1 and CR2. This mod appears to be done already as well.

Honestly I am wishing I could find someone with a tube amp that is too tame for them and make a trade. But I doubt that's gonna happen before I do some mods of my own.

Lastly, I found that lowing the bias in my solid state amp I got much better tone. I am wondering if I can make the bias adjustable in this amp so I can try lowering it to see if it improves the tone like the SS did.


Thanks for your help!

Jeff
 
eyoung thanks for the reply. The schematic shows 6L6gc tubes and the chassis is labeled the same. I think these are what was designed into the amp.

I think EL34's are going to produce even more overdrive aren't they? Or do I have that backwards?

The Triumph 60 only has two power tubes. The 120 is the one with the quad of tubes.

Thanks!
Jeff
 
BR, I think you have a couple things confused.

If you remove one power tube from a pair, it won't hurt anything, but it also won't work right. I think what you have in your mind is when people talk about the 120w version, they suggest removing one PAIR of tubes from the amp, leaving the remaining pair, and causing the amp to become the 60 watt version of itself.

This is a push pull amp, and if you remove one power tube, all you have is push (or maybe only the pull). Since it is class AB, at lower volumes you might get all the waveform, but at higher levels, you start to lose the part that slips into class B territory. If you are hearing "overdrive" at low levels, perhaps it is this missing power tube you are hearing.

Think of it as a choir group, and none of the altos show up to sing.

Before you remotely start looking to modify the amp, do yourself a huge favor. Get the amp working correctly, THEN think about modifications. It makes no sense top start changing a bunch of stuff w3hen the basic underlying amplifier isn't even working right. And besides, once it is correct, you might just LIKE the way it sounds. If you have a stone in your shoe, do you think about ways to put padding around it so you don't feel it, or do you think about removing the stone?

The biasing of a solid state amp is really not much like biasing in the tube amp. This is one of the things to leave for later, it is not going to do what you expect.


Power tube overdrive only occurs when you overdrive them. In this 60 watt amp, if you are lazing along at 20 watts, the4 power tubes are not overdriving. It won't matter 6L6, EL34 or 6550, they won't be overdriving until the amp is fully maxed out. SO changing to EL34 is not going to change the amount of overdrive.


This amp is 100% designed around 6L6 tubes. 500v may be high according to the book, but it is dead on stock in this amp, and in MANY MANY other 6L6 guitar amps.

The stock bias is not adjustable, and is -56v by design. (Within the normal voltage variations in a typical amp) The supply can be easily enough be modified to reduce the bias voltage to run the tubes hotter, but if you want higher voltage on the bias you will have to add a voltage multiplier or reconfigure the supply in some other fashion. If we were to engineer EL34 into this amp, you would want to drop the bias to about -42v.

BUT BE CAREFUL. If you want to use EL34 in this amp, then you DO need to make changes. The 60 watt Triumph has no screen resistors, and your EL34s would want them. Cut traces and add them to the power tube board. The bias would have to change. Pin 8 is the cathode and is already grounded, but the EL34 also needs pin 1 to be grounded. Pin 1 in a 6L6 is not used, so Peavey was free to use pin1 for other conveniences, which they did. The heater current to pin 7 passes through pin 1 on this board. You'd need to cut traces and rewire the heater pins 7 plus rewire pins 1 to the adjacent pin 8 of each socket. The other major concern would be that the EL34 wants 600ma more heater current per tube, so we are asking the power transformer for another 1.2 amps. Peavey did not use the same power transformer for both 120w and 60w models. But fortunately, Peavey power transformers are generally made very robust, and should at least have no trouble with more heaters.
 
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Enzo

BR, I think you have a couple things confused.
No argument there Enzo. lol
This is a push pull amp, and if you remove one power tube, all you have is push (or maybe only the pull). Since it is class AB, at lower volumes you might get all the waveform, but at higher levels, you start to lose the part that slips into class B territory. If you are hearing "overdrive" at low levels, perhaps it is this missing power tube you are hearing.
Well this is why I ask before trying something like this. I understand the push/pull concept from my research when I was working on my Fender amp. That's why I was asking because I don't see how things are going to work if I pull one power tube.
It makes sense that people with the 120 may pull two tube to make it a 60.

I'm not hearing anything funky yet (other than gobbs of overdrive) and I haven't removed a tube. The only thing I have done so far, aside from endless experimenting with settings, pedals etc, is to pull each tube, spray the contacts with cleaner and slide them in and out several times to clean the contacts and sockets.


Before you remotely start looking to modify the amp, do yourself a huge favor. Get the amp working correctly, THEN think about modifications. It makes no sense top start changing a bunch of stuff w3hen the basic underlying amplifier isn't even working right. And besides, once it is correct, you might just LIKE the way it sounds.
I don't think the amp is malfunctioning. If I were after a hard rock sound I would be happy just the way it is. This amp has a lot of body to the sound. Its way different from my Fender. I love my Fender! I am honestly very happy with the results. But after hearing some tube amps, I see there are improvements to be had. I wish I could get a fuller tone from it like this Peavey because the Fender is the sound I am after, its just missing that tube element. If I could get my Fender to produce even half the body this Peavey does, I would totally be happy.

The Peavey is certainly usable as is because it has a bitchin sound, just not what I am currently after. I was holding out for a Valve King 112 but this deal came along and I couldn't turn it down.

The biasing of a solid state amp is really not much like biasing in the tube amp. This is one of the things to leave for later, it is not going to do what you expect.
Ok. I was thinking it would produce similar results because I used to have a Carvin X100B that I modded to have adjustable bias and I experimented with with bias settings and it made a difference. It wasn't as dramatic a change as I get on my Fender but it was a noticeable difference.

BUT BE CAREFUL. If you want to use EL34 in this amp, then you DO need to make changes. The 60 watt Triumph has no screen resistors, and your EL34s would want them. Cut traces and add them to the power tube board. The bias would have to change. Pin 8 is the cathode and is already grounded, but the EL34 also needs pin 1 to be grounded. Pin 1 in a 6L6 is not used, so Peavey was free to use pin1 for other conveniences, which they did. The heater current to pin 7 passes through pin 1 on this board. You'd need to cut traces and rewire the heater pins 7 plus rewire pins 1 to the adjacent pin 8 of each socket. The other major concern would be that the EL34 wants 600ma more heater current per tube, so we are asking the power transformer for another 1.2 amps. Peavey did not use the same power transformer for both 120w and 60w models. But fortunately, Peavey power transformers are generally made very robust, and should at least have no trouble with more heaters.
I have no desire to make such big changes. I'm not interested in changes to EL34's anyway. It was just a question based upon an earlier comment.

As always, I really appreciate your teachings. You always explain things so that we can gain a working knowledge and make educated decisions.

Thank you!
 
Here's a link to the page at eurotubes.com with the Peavey tube sets.

https://www.eurotubes.com/cart/index.php?page=view_products&category_id=8&sub_category_id=93


Peavey Ultra 60 Full Low Gain Retube KitPrice: $87.00 Description: For you guys who want to tame the gain a bit in these amps. This includes a matched pair of the JJ 6L6GC's, one standard ECC83S for V1, two ECC832's for V2 and V3 which lowers the gain in the crunch and Ultra channel by about 40% and one balanced ECC83S for the phase inverter in V4.

https://www.eurotubes.com/cart/index.php?page=view_submenu&category_id=8Seems like these would get me closer to what I am looking for. That's why I was originally asking for input.

Thanks!
 
djgibson51

Just to clarify - is the clean channel clean?
Is it just the crunch and ultra channel that is too over the top for you?

The clean channel is nice. It is very similar to the clean channel on my former Carvin tube amp. Its ballsey but clean. I haven't turned it up real loud on the clean channel but I bet it sizzles at high volume.

Thanks!
 
OK. Just like mine.
If the diodes in the crunch/ultra channel haven't been removed/ jumpered then there will be distortion at any volume.
If the diodes are out of the equation then you can play with the gain from V1a, V2b, V2a.
A simple start point is in my first post, but their are lots of choices and you can tailor your own tone here, experimenting and learning as you go - carefully. That 500 plus supply scares me.
 
If they are removed/jumpered it is moot, but the diodes CR1 and CR2 are not clipping diodes, they snip out a bit of signal right at zero crossing to reduce noise. They are only in the gain channel, not the clean channel, so they have no effect on clean. Later models like the JSX added a 1M pot in parallel with them so you could dial it from fully noise reduced to no diode action, or anywhere in between.

Did you note in the gain channel, the only difference between crunch and ultra is the value of the pre gain pot? So crunch simply works with a lower level of input signal.

If you like the clean channel, consider doing what many do, leave the amp on clean and use an overdrive pedal out front as the other channel.


If you want to mess with the gain channel, tube swaps or cap changes or more, remember that V2 is only used in the gain channel, both halves, and can be changed to good effect without bothering the clean channel. V1 is used as the input stage as so affects all channel, while the other half of V1 is only used in the gain channel. SO if you change out V1 trying to tame the amp, you may also change the clean channel.

I think lower gain tubes were mentioned in earlier posts, and considering V1, you could also consider some of the combinations tubes like the 12DW7/7247 or the ECC832 or ECC823. I never remember which side of which is the low gain, but those tubes are like half 12AX& and half 12AU7,
 
It does cause a little crossover distortion, but it only is on the distortion channel anyway, and it is a small amount, so it usually gets lost. To those that hear it and prefer it gone, the mod is simple, as you can see.


Imagine it was on the clean channel and you had a large since wave passing through. Now imagine that right on the zero volts line, you snipped out a thin strip. The diodes need about a half volt to turn on, so any signal less than half a volt is blocked. That includes most noise signal. But if we have something like 30v of signal, that half volt doesn't look like so much. So after we trim off that half volt at the base of the waveform, the rest continues on.
 
JMFahey, I've watched that video you posted. That's what my amp sounds like. Though my amp is a head only. I took my Line6 SpiderJam and wired the speaker with a guitar cable and added a jack coming from the amp (Line6) to plug the speaker in. Now I just unplug and plug it into the Triumph, which has a Celestion 70/Eighty installed. It has a bitchin' sound! I can mimic Foreigner, Sammy Hargar and others to the T. For hard rockin' this is one bad *** amp, no doubt about that.
I have been experimenting with volume on my guitar. I can turn the volume back to about 3 and it kind of muffles the tone a bit and I get a rather nice Fender vintage kind of tone. This amp gets some very cool blues tones in this current configuration when I use the neck pickup.

I honestly think a master volume would be a major step in the right direction. I can adjust this thing to different settings on either of the drive channels and get something really cool but its rumbling the walls. At that point I can either drop the pre or the post knob but either way, it loses the tome that is so appealing at these settings. If I could keep the settings and just drop the over-all volume it would be awesome. I understand that dropping the volume would change the amount of air being moved by the speaker etc. but I think we would live with that part.

I tried one of those "Magic" volume boxes, I got from ebay a few years ago, that goes between the preamp out and the power amp in and it does accomplish what they say but just plugging it in is a detriment to the tone. Of course better quality parts may make a difference. I am sure these ebay sellers are using the bare minimum where quality in parts is concerned.

Is adding a master volume a reasonable upgrade on this amp? Or would that be a major pain in the butt?

Thanks!
 
Putting a volume box in the FX loop is the same thing as adding a MV.

Part of losing tone when you go from loud to soft is your ears. Look up "Fletcher-Munson curves". And your speaker is a mechanical thing, and it responds differently when it is being asked to go LOUD and when only playing quietly.

When you get some tone you really like when loud, it is really difficult to get it to come out at low levels.
 
Enzo

Enzo

Thanks for the info. I was wondering if a MV was just a volume between the pre and power amp. Thanks for filling me in!

Lowering the volume doesn't produce a bad sound from this amp. There is something I have noticed about this one, it can be choked back severely with my guitar volume and while the sound gets muffled, or slurred, it really doesn't lose the fidelity. The sound takes on a familiar tone I hear in a lot of the music I listen too. Its really interesting what I have discovered about this amp this past weekend. I think I played it for about 15 or so hours and tried every setting I could to see what I could come up with. I have found that I can get some pretty bitchin' tones by really choking the volume on the guitar and trying different amounts of drive. I imagine this is old hat for many here but for me this is a whole new avenue learning to manipulate a tube amp. I never got this far when I had my Carvin tube amp, because I wasn't at the point of being cognizant of tone. In the last year I have learned a lot more and am finally beginning to understand what to look for and how to recognize it when I get there. So you were right, experiment and you just might find that you love the amp. For the time being, I can't say I love it yet but it sure has my attention. Its amazing hearing how well this amp articulates the notes and how easy it is to bloom a note by changing the way I strike the string etc. I was beginning to find this with my Fender amp (on a much smaller scale) but this amp makes it so easy, it almost does it for me. I honestly can't see myself ever going back to a solid state amp. But that is a different post...
 
I have one of these, but haven't played it in a while. If I recall correctly, without the foot pedal connected it usually is in distortion mode (or "Ultra"). You can jumper the foot pedal jack to put it in clean mode with a bent paper clip if you don't have the pedal. I did some mods on mine a long time ago, and do remember this amp is not the easiest to work on - it has several circuit boards all kind of crammed into the chassis. If you don't have the foot pedal I'd strongly suggest you track one down if you plan to use the amp much.
 
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