#1
I recently bought a Peavey Valve King 50 amp. While I love the amp for it's versatility, features, quality and the clean channel; I'm not so in love with the dirty channel. It's too gainy for what I most like to play - classic rock. I find myself setting the gain between 1-2(anything higher is too much) and with that narrow of a window it's very hard to nail down a good classic rock tone. The gain nob very sensitive to the tiniest adjustment. I'm relatively new to electric guitar and this is my first tube amp. In short I think I'd like to tame it down a little. After some research I'm gonna try switching the V2 preamp tube from the stock Ruby 12AX7 to either a 5751 or a JJ 12AX7-MG. Which one would be best? I'm leaning toward the MG for fear that the 5751 might be too mellow. Like I said, I like to play classic rock mostly but I go as hard as old school metal - Maiden, Priest, Sabbath, maybe some Metallica or Megadeth but nothing heavier. Which is the best tube for this? Good classic rock tones(Rush, Zeppelin, Aerosmith) is the most important thing to me. 5751 or 12AX7-MG? Any advice is appreciated.

PS I'm currently using an tube OD pedal(CM-2) on the clean channel or else on the dirty channel with the amp gain turned down as low as I can get it(and still have sound). That's because the gain nob on the pedal is more controllable than the gain on the amp. Not really sure if this is the best way to go but it works.
#2
Quote by hotrodney71
I recently bought a Peavey Valve King 50 amp. While I love the amp for it's versatility, features, quality and the clean channel; I'm not so in love with the dirty channel. It's too gainy for what I most like to play - classic rock. I find myself setting the gain between 1-2(anything higher is too much) and with that narrow of a window it's very hard to nail down a good classic rock tone. The gain nob very sensitive to the tiniest adjustment. I'm relatively new to electric guitar and this is my first tube amp. In short I think I'd like to tame it down a little. After some research I'm gonna try switching the V2 preamp tube from the stock Ruby 12AX7 to either a 5751 or a JJ 12AX7-MG. Which one would be best? I'm leaning toward the MG for fear that the 5751 might be too mellow. Like I said, I like to play classic rock mostly but I go as hard as old school metal - Maiden, Priest, Sabbath, maybe some Metallica or Megadeth but nothing heavier. Which is the best tube for this? Good classic rock tones(Rush, Zeppelin, Aerosmith) is the most important thing to me. 5751 or 12AX7-MG? Any advice is appreciated.

PS I'm currently using an tube OD pedal(CM-2) on the clean channel or else on the dirty channel with the amp gain turned down as low as I can get it(and still have sound). That's because the gain nob on the pedal is more controllable than the gain on the amp. Not really sure if this is the best way to go but it works.


ok I use a VK 50 myself for practice but have a different approach than you are using (have a CM-2 as well) try using the overdrive as boost instead of as your source for gain. by this I mean turn the volume knob up most or all the way and the gain down to maybe 1. this will slam the front of the amp with a signal and let the amp do the distorting. also if you are using the boost button turn it off as that may be where your problem lies. of course you can replace one of the 12ax7 with a 12au7 for less gain as well. I run my gain around 3-4 depending on what guitar I'm using. you really should have no problem getting classic rock distortion form the amp as that is one of the things it's good for.
#3
If you are playing with the gain that low I would go lower than a 5751. I'd think about a 5751 in V1 and a 12AT7 in V2, perhaps even a 12AY7.
You could try the mid-gain JJ in V1 but I wouldn't expect much difference out of it in V2.
#4
It might seem simple but I second making sure the 'boost' button isn't engaged, the regular gain on the dirt channel should give you a much wider window of use for rock then you are describing, at least that was my experience when I had a VK 112
#5
Quote by Roc8995
If you are playing with the gain that low I would go lower than a 5751. I'd think about a 5751 in V1 and a 12AT7 in V2, perhaps even a 12AY7.
You could try the mid-gain JJ in V1 but I wouldn't expect much difference out of it in V2.
I thought the V2 was the tube that generated the gain signal. Am I wrong on that?
#6
monwobobbo Boost is off. I'll try using the OD pedal like that. I should mention that so far I've only played on the 2W low power setting. Perhaps the amp has completely different characteristics at 12 and 50W? I need to wait for my u[stairs neighbors to be away until I can crank it. I need to break in the new retro 30 speaker too.
#7
Quote by hotrodney71
I thought the V2 was the tube that generated the gain signal. Am I wrong on that?

Yes. The first four gain stages when you're on the lead channel are V1A, V1B, then V2A and V2B. These are cascaded, so while it is true that V2 is used only on the gain channel, it's totally backwards to say that it "generates" that signal. When you're on the lead channel, your signal goes through both halves of V1 first, and since each stage multiplies the gain of the earlier one, V1 is going to make a bigger difference in how that sounds than V2. This is true of nearly every amp, and in general the later the gain stage the smaller the effect of the tube on the overall sound. It's like a game of telephone - the third and fourth people in line can talk as clearly as they like, but if the first guy in line mumbles badly, it's too late to fix the problem.

You can try a different tube in V2, and if you only wanted to effect the lead channel that would be the one to swap, but since it's farther downstream it's going to be harder to influence the distortion. I think if you are trying to knock down the gain on the lead channel you're going to want to go down to a 5751 or 12AT7 at least in V2. It's not that V2 won't effect the OD channel, it's that I don't think the mid-gain 12AX7 is going to make much difference, since you're starting at the third gain stage and trying to 'undo' the already cascaded stages of V1A and B. Much better IMO to knock down the gain right off the bat with a lower gain V1 tube, assuming you can spare the volume on the clean channel.
#8
Quote by hotrodney71
monwobobbo Boost is off. I'll try using the OD pedal like that. I should mention that so far I've only played on the 2W low power setting. Perhaps the amp has completely different characteristics at 12 and 50W? I need to wait for my u[stairs neighbors to be away until I can crank it. I need to break in the new retro 30 speaker too.


well mine only runs at 50 watts so I can't comment on that. volume does change tonal dynamics though so settings that work at bedroom practice levels don't necessarily work at band volumes. this is something you have to keep in mind and set the amp accordingly. cranking it won't suddenly make it have great tone.

I had mine out today and am still confused by your distortion issues. what tones are you going after exactly as this might help getting you advice that will work
#9
monwobobbo I'm mostly looking for classic rock tones like Rush, AC/DC, The Who, etc. I've come pretty close but I'm just surprised at how low I have to set the gain. You right about the volume, cranked at 50 amps allowed me to turn the gain up a notch to 3 before it got harsh and muddled. This amp is way more gainy than I was expecting. Update - I got a JJ 5751 and installed it into what I think is the V2 socket(they're not labeled!). The result wasn't what I expected at all. It definitely "cleaned" up the clean channel and created more headroom there(not really what I was look for) but it didn't change the gain characteristics on OD channel 1 iota. It also brightened up the amp considerably(both channels), Again - not what I was looking for! I thought JJ tubes were supposed to be dark. On the good side, I did notice a little better clarity in the overall sound with the tube change. I'll try it in the V1 next. I also have a JJ 12ax7 and some Beijing 6N4's on the way to try out. I'll figure it out the fun way I guess - trial and error. Is your amp the 2nd generation VK 50 or the original VK 112? Can you help me out on which valve is which? I'm assuming the 1 on the right, closest to the guitar input is V1, wasn't sure on the other 2. Thanks for the replies.
#10
Quote by hotrodney71
monwobobbo I'm mostly looking for classic rock tones like Rush, AC/DC, The Who, etc. I've come pretty close but I'm just surprised at how low I have to set the gain. You right about the volume, cranked at 50 amps allowed me to turn the gain up a notch to 3 before it got harsh and muddled. This amp is way more gainy than I was expecting. Update - I got a JJ 5751 and installed it into what I think is the V2 socket(they're not labeled!). The result wasn't what I expected at all. It definitely "cleaned" up the clean channel and created more headroom there(not really what I was look for) but it didn't change the gain characteristics on OD channel 1 iota. It also brightened up the amp considerably(both channels), Again - not what I was looking for! I thought JJ tubes were supposed to be dark. On the good side, I did notice a little better clarity in the overall sound with the tube change. I'll try it in the V1 next. I also have a JJ 12ax7 and some Beijing 6N4's on the way to try out. I'll figure it out the fun way I guess - trial and error. Is your amp the 2nd generation VK 50 or the original VK 112? Can you help me out on which valve is which? I'm assuming the 1 on the right, closest to the guitar input is V1, wasn't sure on the other 2. Thanks for the replies.


not really the guy to tell you much about tubes that would be Cathbard. for starters you need an overdrive as I really think that will help tighten up the sound for you. the other big thing is that you might have higher expectations for the VK. the VK is a basic amp that is low priced (in comparison to bigger name amps). because of this it really isn't meant to be able to nail the tones of far more expensive amps. close is about as good as it gets.

The Who and AC/DC don't use much gain at all so cranking the gain won't get you that sound anyways. the Who used Hiwatts and the distortion is more power tube but that requires a great deal of volume, same with AC/DC. so on the VK you would only use a bit of gain and getting kinda close is about all you can do. Rush depending on what era is doable on the VK but again you can't really expect to nail Alex's tone plus you'd need the other fx he used to really get that sound. again get an overdrive and see what happens. what guitar (s) are you using?

my VK is a 1st series but sound wise there is no difference to version 2.
#11
monwobobbo I have an OD pedal(hardwire CM-2) and it does tighten up the sound. My guitars are Epi LP standard pro and Fender Strat(texas special coils). You're probably right in that I was a little starry-eyed because this is my first tube amp. I see what you're saying with the difference in pre-amp gain and power tube distortion and I think I'm looking mostly for the latter. This is probably the best amp I'm ever gonna own so I want to get the most out of it and I don't mind investing in simple part upgrades. I've already replaced the stock speaker with a WGS retro and I think that was very worthwhile upgrade. Now I'm trying to get a tube combination that works for me(tames down the OD a little). Choosing a speaker was hard enough as I was torn between the retro 30 vet 30 and eminence guvna. Tube choices are mind boggling and some of the old stock are pricey. Overall I'm pretty happy with the VK, like it much better than my Fender mustang which is soon going up for sale.
#12
I concur with the suggestion to run a 5751 in the V1 with a 12AT7 in the V2.

Way I figure it, between picking up those tubes and the current 12ax7 tubes you have, you should be able to mix and swap enough to figure out some combination of tubes that fits your needs.

As far as what brand, I haven't had any bad luck with any specific brand lately... from what I use, that is. I have used Tung-Sol, Electro Harmonix, JJ/Tesla, and Ruby (It's a JJ with their label on it). None of them have given me any fits. Some are said to be darker or brighter than others. A Tung-Sol 5751 might work well for you. As for the 12AT7, I'd go JJ/Tesla on that (ECC81 is likely how it will be labeled online).
Gear: Gibson Les Paul Studio, Gibson SG Special, Fender Stratocaster, Fender Telecaster, Fender Jazzmaster, Gretsch Pro Jet, Carvin C350, Epiphone ES-339 P90, Epiphone ES-335 Pro. Peavey 6505, Sovtek MIG-100, Vox AC30, Peavey XXX.
Last edited by ThunderPunk at Aug 18, 2016,
#13
ThunderPunkI'll try a 12AT7. Is that a direct replacement for the 12AX7 with no modifications needed to the circuitry?
#14
Plug and play, no mods necessary.
Gear: Gibson Les Paul Studio, Gibson SG Special, Fender Stratocaster, Fender Telecaster, Fender Jazzmaster, Gretsch Pro Jet, Carvin C350, Epiphone ES-339 P90, Epiphone ES-335 Pro. Peavey 6505, Sovtek MIG-100, Vox AC30, Peavey XXX.
#15
Quote by hotrodney71
monwobobbo I have an OD pedal(hardwire CM-2) and it does tighten up the sound. My guitars are Epi LP standard pro and Fender Strat(texas special coils). You're probably right in that I was a little starry-eyed because this is my first tube amp. I see what you're saying with the difference in pre-amp gain and power tube distortion and I think I'm looking mostly for the latter. This is probably the best amp I'm ever gonna own so I want to get the most out of it and I don't mind investing in simple part upgrades. I've already replaced the stock speaker with a WGS retro and I think that was very worthwhile upgrade. Now I'm trying to get a tube combination that works for me(tames down the OD a little). Choosing a speaker was hard enough as I was torn between the retro 30 vet 30 and eminence guvna. Tube choices are mind boggling and some of the old stock are pricey. Overall I'm pretty happy with the VK, like it much better than my Fender mustang which is soon going up for sale.


nothing wrong with better tubes but the only way to get the power amp distortion you seem to want requires massive volume which isn't practical these days. look for a more practical compromise. are you using the overdrive as a boost (volume maxed, gain on maybe 1 or 2 at most, tone to taste)? despite having a "better" amp I'm fond of my VK as well. it's a solid amp just not going to be a tone of the gods amp. I'm all for getting the most out of the gear you have great way to learn just keep the expectations reasonable
#16
I like this chart for comparing preamp tubes (never used the shop, no affiliation just a cool chart) http://www.kcanostubes.com/content/preamp-tube-gain-and-compatibility-guide

I bought a bunch if different JJs trying to tame my 5150 green channel.
Guitars:
Ibanez RG1570 Prestige
Jackson Kelly KE3 - MIJ (Distortion/Jazz)
Jackson DKMGT Dinky (EMG 81/85)
ESP E-II Eclipse Custom (JB/'59)
ESP LTD EC-1001FR (EMG 81/60)
Fender MIM Strat

Amps:
Mesa/Boogie Dual Rectifier Roadster 212
Laney IronHeart IRT-Studio
Peavey Vypyr 30
Peavey ReValver Amp Sims
TOOOO many T.C. Electronic Pedals. . .
#17
Been awhile but I thought I'd give an update. After trying many tubes(new and old stock), 12ax7, 5751 and 12at7 plus a speaker change(wgs retro30), changing guitar vol and tone settings, this amp's od channel just continues to sound harsh and muddy and only usable on gains of less than 3 with the 5751's, 2 with 12ax7's. I've got a nice collection of tubes though and I discovered that one of the cheapest is also one of the best - the beijing 12ax7(nos from the 70's). The stock ruby 12ax7 ac5's actually weren't that bad(sounded better than jj's). I just bought a monoprice 15w tube amp and all I can say is WOW! Now this is what a classic rock amp is supposed to sound like! It completely blows the VK away and I paid....$188! Only 15w but that's plenty for me right now. The VK sounded best on the clean channel with the volume way up to where you get a nice break-up. It also sounded better with single coils than humbuckers. I was gonna try a smooth cone speaker(wgs g12c/s) to try to tame it down but after getting the monprice, I think I'm done with the vk. I really wanted to like it but even my gf says my new amp sounds much better. Anyone want to buy a VK 50?
#18
that's cool. not every amp is for everyone so glad you found something you like better.
#19
Yeah the VK is a well made amp with a lot of nice features but it just doesn't have the sound I was looking for. The monoprice does. For the price, I just can't believe how good this thing sounds.