Peavey Classic series amps.
The Classic series amps have got to be one of the best working man’s amps ever built. For a production made amp they are built well and sound great. These amps are fixed bias and use EL84 power tubes. They provide a crisp, warm tone when using tubes with a moderate natural plate current draw. If it’s a good blues tone your after then a fairly hot set of EL84’s will give a nice greasy tone with an early saturation. The drive channel is pretty good adding a nice smooth distortion when using good tubes. With the stock Chinese 12AX7’s or sovteks (the EH and new tungsol tubes included, as they are sovteks) it has a nasty honk!
Peavey has started to use some of the JJ Electronic tubes and later JSX amps have been showing up with the JJ EL34’s and even a few JJ ECC83S’s!
If your looking for Pawn shop treasures make sure you keep your eyes open for the discontinued Rockmaster preamps and the little Classic 20. Bob has one of each of these in his collection. The RM preamp is one of the nicest and most versatile preamps for the price. The Classic 20 is a gem for a small cheap combo. It’s very much like the Fender Pro Jr. Bob purchased a Weber AlNico P10N for his C20 (he paid more for the Weber than he paid for the C20!) When the Weber arrived he realized it wouldn’t fit! The magnet on the P10N is huge! So he had to take off the bell cover and remove the speaker board from the amp and saw off 3/8″ from the bottom of it to drop the speaker down. Now the EL84’s clear the magnet by 1/8″. As for the tone? It was very well worth the money and effort. The P10N is an excellent speaker with a top end chime second to none. The bottom end is extended and very tight and the breakup is oh so smooth!
Peavey Butcher, Ranger, Roadmaster, Triumph and Ultra amps.
These are all early Peavey amps that are 6L6 based and steadily progressed ending up with the Ultra and Ultra plus. These are all fixed bias amps and need warmer grades of tubes to sound good. They have plenty of gain for a classic rock and early metal styles and they are well built and roadworthy.
Peavey 5150 and 6505 amps.
The 5150 and the 6505 are the same amps and they have an insane amount of gain in the preamp section. Players who only play gained up are usually pretty happy with the 5150 heads in stock trim, but players looking for warmth and anything near a decent clean tone will be left wanting. The power tubes while running just under 500 plate volts are only drawing about 10 to 12 milliamps of plate current. This means the amp is producing what is called crossover distortion and cannot produce a good warm clean tone to start with. It also causes the amp to be sluggish and lack dynamic response.
The 5150 combo and the Ultra combo are another story. For some reason PV got it right and although the combo amps are also fixed bias they are fixed MUCH warmer and we can supply you with power tubes that will get the bias between 38 to 42mA which is right where they belong with NO bias mod.
If you check a stock 5150 100 watt or an Ultra plus 100 watt head using an oscilloscope and a signal generator which is the classic old school method of biasing a tube amp, you can plainly see crossover distortion in the wave forms until you get to about 33 to 34 milliamps of plate current then the sine waves look perfect. We like them set at 40 to 42mA per tube. Now you 5150 players who have played or own the 5150 combo don’t have this problem, for some reason the combo’s are biased much warmer and with the correct grade of power tubes they will bias up to a very nice 38 to 42mA with no need to modify them. This is why most players who have tried both the head and the combo, like the clean tone and the combo’s dynamic response better.
There are a lot of amp techs out there that have attended technical trade schools or have taken a couple college courses and have no real understanding of how and why vacuum tubes work. They for the most part have never read or studied any of the classic tube manuals but most of them will be very quick to say, “Bias? No, you don’t have to worry about that, it’s fixed bias.” So if you’re looking for a tech to bias your amp properly and you get this answer say, “Gee thanks!” and quickly move on to the next tech because they obviously know nothing about tube amps.
For you 5150 players who want to venture into “integrated Quad” territory without doing a bias mod, we have you covered! This is a stock 5150! There are NO mods necessary to run this setup. Now it will sound better with a bias mod but it’s NOT necessary. We put this combination together especially for you guys who don’t want to hassle with the bias mod or do not have anyone you trust to do it.
As you can see by the bias meters on the left even very hot 6L6GC’s only pull about 10 milliamps of plate current where they should be pulling about 40mA ( the far left bias meter ).
The KT88’s are pulling about 32mA ( the right bias meter ) where they should be pulling about 60mA. But, for you guys who are happy with the stock tone or just don’t want to mod the amp then this Integrated quad with the JJ KT88’s in the outside sockets and the JJ 6L6GC’s in the inside sockets will get you even more low end thunder and a very fat and punchy all around tone. The only thing necessary to install these is to clip the rather useless tube retainers from the two outside sockets so the big bases on the KT88’s will fit. ( Note the clipped retainer halves sitting on the amp.)
This Integrated quads are plug and play, we repeat PLUG AND PLAY!!
In July of 1999 Bob tubed a 5150 for a local guy named Jeff Miesen, better known as Jeffytune on the Peavey forum. The Peavey amp forum used to be one of the only real open forums on the net, but unfortunately this changed the summer of 2001 and now if you post something that Peavey doesn’t like your post will be deleted. Jeff was real happy with the JJ Electronic 6L6’s and ECC83’s that we loaded his amp with, but we felt the amp could be improved with a bias mod. Jeff was leery about the mod and didn’t want to part with the $40.00. A few weeks went by and curiosity got the best of us. We really wanted to hear what a 5150 sounded like with the power tubes biased properly so I called Jeff and offered to pick up his 5150 and mod the bias free of charge! Jeff said yes! With the bias dialed in to about 34 to 35 mA on the plates which was just out of crossover distortion the amp was much improved! It now had a good warm clean tone and the dynamic response was much improved. We promptly called Jeff to come get his amp. After hearing it he was impressed, a total success!
In August of 2000 Bob decided to mod a 5150 using an idea he was going to use on a 100 watt Marshall. The mod consists of a split dual bias circuit allowing the amp to run all 6L6’s or a pair of KT88’s in the outside sockets and 6L6’s in the inside sockets or any combination of EL34’s, 6L6’s and KT88’s. He called it the 5150ex for experimental. There are now two bias pots on the back panel for easy access, a reworked front panel and hard wired milliamp meters, one for the two inner tubes and one for the two outer tubes.
After trying all of the above tube combinations at lots of different bias settings (this thing is a great test bed!) The favorite combination was a pair of JJ E34L’s in the center sockets set at plate current draw of 44mA and a pair of JJ KT88’s drawing 65mA in the outer sockets. At these settings the amp makes 113 watts before any clipping. In stock trim a 5150 is well into clipping at 100 watts. This amp gets run hard multiple times a week since August of 2000 with NO problems what so ever.
The 5150 ex is a beast! It also exhibits a very fat, warm clean tone. The distortion in the clean channel alone is more than most players need! The lead channel is just simply over the top, way over the top! With it’s Zebra wood front panel and snake-skin covering it’s not bad looking either! Just about every local player that comes in for tubes wants to play it and we never say no because it’s great to see and hear their reactions. The Marshall players seem to be most impressed.
On 07/24/01 the second Peavey 5150ex was born! The proud owner is Steve Frost a local guitar hero here in Portland Or. Notice the two trim pot stems just to the right of the right hand KT88. The amp is still creating smiles and running strong!
Peavey 5150 II and 6505+
The 5150 II and 6505+ are the same amps and fall into the love it or hate it category. We get calls and emails all the time from players who sold or traded their original 5150’s off for the 5150 II or 6505+ and the question is always, “how do I get my 5150 II or 6505+ to have the balls my 5150 had?” Unfortunately the answer is you can’t get there from here… The voicing on these amps is totally different than the original 5150 and Peavey chose to basically neuter the 5150 II. It simply does not have the low end grunt and raw sound that the original had. This is not bad, its just different and you will find plenty of players who love the 5150 II.
I’m questioned a lot as to the bias adjustment on the 5150 II and 6505+. This amp does have an adjustable bias but the available sweep is pretty narrow and the only way to get the power tubes out of crossover distortion is to lower the resistance to the circuit and once again this is a very easy mod and well worth it. Inside the amp there is a small circuit board that has the bias trim pot mounted on it and the final bias resister which is a 12K 1/4 watt resister. All that’s necessary is to replace that resister with a 6.8K 1/4 watt resister which will increase the window of available bias adjustment. A final bias setting of between 36 to 40mA of plate current per tube measured with a bias probe is a good setting. You only need to probe one tube, set the bias for it and you’re done.
The bias pot is located right next to the power tubes so if you use a short bias probe you don’t even have to remove the amp from the chassis. We have our own Eurotubes bias probes which can be used with any multimeter that will do this for 25.00
Peavey XXX , JSX and 3120 amps.
Enter the Triple X. Peavey was listening… The bias sweep on this amp can get either a quad of 6L6’s or E34L’s up to the proper bias level and if you really want to know what the bias is set at we would suggest you get a bias probe to check it with because the test points on the amp are measuring voltage and not plate current. We cannot stress enough how inaccurate the test points are! We just tubed a pair of JSX heads that were modded by Voodoo amps including the Mercury Magnetics VA-JSX-0 output tranny’s and because we get asked about the bias test points almost everyday we decided to document the readings for you. Running KT77’s in the EL34 mode with a probe installed and the bias set to 36mA the test points measured 45 volts. Then we turned the bias down to a cold 20mA and the voltage at the test points read 48 volts. So a difference of 16 milliamps measured with a bias probe only showed a 3 volt difference at the test points!
An update 10/09/07 We just measured the bias on a XXX in the EL34 mode and with the bias set at 42 volts using the factory test points (Peavey recommends 42.5) the bias was a whopping 57mA which is over 100% of dissipation! You will burn up your tubes with all but the coldest grades of EL34’s or KT77’s. With the bias set to 45 volts at the factory test points the bias went way down to a very acceptable 37mA. So in this particular amp a variation of only 3 volts at the factory test points made an incredible 20mA difference in bias!!
Do NOT bias your XXX ,JSX or 3120 for any EL34 type tube including the JJ KT77’s using the test points! The 55 volts that Peavey recommends at the test points for 6L6GC’s is on the other hand, on the cool side but using the test points is so completely inaccurate we simply cannot warranty tubes to players who use the test points to bias these amps!
It was brought to our attention that there was a post on the Peavey forum and it stated that the bias on the XXX did not have enough range to get the power tubes too hot. This is not true!! There is plenty of adjustment especially in the EL34 mode to fry any tube!
Moral of the story? PLEASE do not rely on the test points to bias your amp! You will be lucky to get in the same neighborhood as the ballpark, let alone in the ballpark. These are not cheap amps and the bias is SO easy to set accurately that you owe it to yourself, your amp and your tone to do it right! There are short bias probes available on Ebay and from several other sources including our own Eurotubes bias probe for 25.00 so it’s a VERY cheap tool, very accurate and very easy to use.
We have been asked by our XXX ,JSX and 3120 customers to do a bias video on these amps and we finally got around to it. You can see the video here, You don’t need to measure the plate voltage you can simply bias EL34’s, KT77’s or 6L6’s between 34 to 40mA. Most players like them right at 36 to 38mA.
We find more often than not that the JSX ,XXX and 3120 amps are hot in the EL34 mode and some are pretty cold in the 6L6 mode. So if you’re biasing 6L6’s and the bias will not get up above 34mA then adjust it down to about 20mA and put the amp in standby. Then set the bias select switch to the EL34 mode. YES YOU READ RIGHT! We said to put the bias switch into the EL34 mode if the bias will not exceed 34mA with 6L6’s, or if you just want to run a little higher up to about 40mA. Then switch the amp back into the play mode and the bias will jump up from about 20mA to about 35mA and you will have plenty of adjustment to get even the coldest 6L6’s biased properly. This is completely safe to do. Now for all you guys who do this and then ask us if you should switch back to the 6L6 mode the answer is NO, NO, NO!!! If you bias 6L6’s in the EL34 mode then you MUST leave the amp in the EL34 mode.
The bias pot is located right next to the power tubes so if you use a short bias probe you don’t even have to remove the amp from the chassis. We have our own Eurotubes bias probes which can be used with any multimeter that will do this for 25.00 Here is a pic of a probe in one of the sockets of a XXX that shows the bias trim pot and selector.
Here is a bit of information from August 2007: Here is the latest on the screen grid resister problems with the XXX and now the JSX amps.
The XXX amps can use either a quad of 6L6’s or supposedly EL34’s. For the first two years of XXX production our customers (a little over three hundred of them) were all using the JJ E34L’s because they sounded so good in these amps and there were no problems of any kind. About two years into production PV started using sub par screen grid resisters and players started having problems using the E34L’s and even standard EL34’s. PV made a design change in late 2004 going to 700 ohm SG resisters but using the E34L’s is still something we do not recommend because we have had a couple customers now that have blown SG resisters in the new XXX and JSX amps with the E34L’s.
PV has of course blamed the JJ E34L saying it’s the problem but we happen to see it another way. We tube hundreds of Marshall, Mesa, Laney, Ampeg, Crate, Engl, Bogner, Carvin, Gibson, Hughes & Kettner, Orange, Rivera, Traynor and VHT amps just to name a few and none of these amps have any problems what so ever using the E34L’s so we think this speaks for it’s self… PV can not tell you by serial number if your amp has the upgraded SG resisters but it seems to be moot, because there are still problems with the new amps.
If all of this is too much information, the bottom line is that we do not recommend using E34L’s in the XXX or JSX amps. In other words use at your own risk!! This is a shame because the XXX and JSX amps sound great using the E34L’s.
These amps sound great using the JJ EL34 and Peavey has finally taken time to listen! They have swung a deal with JJ and a lot of the new JSX amps are coming straight from the factory with JJ EL34’s. Another option is running the JJ KT77’s in the XXX and JSX amps. These tubes do not draw any more current than EL34’s do so no resistor issues and they sound great with a big chunky low end and a very harmonically rich mid and high end.
If you do want to run the E34L’s and run the amp hard ( who doesn’t ) then we would highly recommend having the SG resistors swapped out for good high quality 700 ohm 5 watts wire wound or sandblock resistors (not parts supplied by PV) which any decent tech can do for about 50.00 and then you will have piece of mind about this.
Back in August of 2000 Bob modified a 5150 to run a pair of KT88’s and a pair of E34L’s at the same. This amp was showcased at the first North West Peavey gathering (Jam, party and Micro Brew celebration for Peavey players) which Eurotubes hosted in late 2000. The news about this amp traveled fast and when Peavey heard about this they said “This can and will not work. The amp will blow up!” Well this amp has been played about every other day now since 2000 and it gets ridden VERY hard and all the components other than the bias circuit including the 100 ohm screen grid resisters and transformers are stock so this is testament that it’s not so much the value of the screen grid resisters, it’s whether or not they are quality parts!
So closing this with Bob’s favorite Confucius quote seems appropriate.
“Man who says it can not be done should not interrupt man who is doing it.”
You can find a page Bob wrote years ago about Roger Crimm’s response at the bottom of this page.
The XXX, 3120 and JSX amps are quite similar with the JSX having a stronger mid and voiced differently in the high end. The XXX has the damping feature on the rear panel but we have found that the tight and medium settings are pretty useless for a big full sound, so you guys that have never tried the loose setting you should give it a shot. As far as the bias goes they are the same. As we mentioned above we had a pair of Voodoo modded JSX heads in (pictured below) and the difference seemed to be that they were a little tighter in general than a stock JSX and the definition was better in the mid and upper mid range which is what we expected from the Mercury Magnetics output tranny compared to the stock unit. The overall difference was subtle but noticeable over a stock JSX. The KT77’s really shine in both the XXX and the JSX amps filling in the low end nicely while supplying a rich and harmonically complex mid. With standard EL34’s these amps lack the low end that most players want now days.
We do get a lot of calls from JSX owners who are disappointed in the amp because they are playing scooped mid metal style so if you fall into this category then I recommend switching over to the JJ 6L6GC’s for power because they have a bigger low end than EL34’s and even more low end than the JJ KT77’s and the mids are not as pushed.
Peavey Valve King:
The Valve King series amps are a cheaply made chinese amp but they do fill a void for players who want to get into a high gain amp for cheap. None of our VK customers have reported problems with them and we get a lot of positive comments about the improvements with the JJ 6L6GC’s and the ECC83S preamp tubes. If you’re moving up from a solid state amp to a tube amp then the VK is a nice stepping stone on your way up. If you’re considering one of these amps we recommend playing one first.
OK PV fans here is a picture of a guitar collection of an internet buddy and customer of mine that I’ve know for a number of years. You PV forum guys ( I miss you ) will know him as PVholic. I thought this needed to be posted simply because, well you’ll see.
You know the old saying “Birds of a feather?” Well here’s proof. This PV collection is owned by Ed Taylor who is ( yup, you guessed it ) a good friend of Charlie, alias Mr. PVholic.
A word about Integrated quads and a rebuttal for Roger Crimm
An article written by Bob Pletka in 2005A few of my customers have brought it to my attention that Roger Crimm from Peavey has written an article about Integrated quads. He has not named Eurotubes as the supplier for this particular set of tubes but he STRONGLY insinuates it and states many things that are false. You can read his article at the bottom of this page. Roger also accuses “this” tube vendor of selling sub par tubes that are not matched and of poor quality.
(I would also like the thank Roger Crimm for his endorsement of Eurotubes! Roger states on his personal website on his tech page, and I quote ” Eurotubes – Don’t buy tubes from this guy”. Anyway, Thanks Roger! It goes to your integrity, and plenty of my customers have acknowledged this!)First I would like to go over a little history. I participated on the PV forum for a couple of years up until August of 2001 which I enjoyed very much. The PV forum was open and no topic was off limits. The players who were regulars there were outstanding people and definitely some of the nicest folks I’ve meet.
It was during this time that I started tubing lots of 5150 and Ultra amps which I found to be biased VERY cold and in July of 1999 I first experienced a 5150 that was actually biased correctly. To me the difference was amazing, taking a cold sounding amp which is known world wide as having a horrible clean channel and a real lack of dynamic response and turning it into an amp worth playing.
I started spreading the news about this on the PV forum at which time I was contacted by Roger Crimm asking me to stop because he was fielding too many questions about bias and why PV had biased their 5150’s incorrectly. My question was the same as everyone else’s, why?? Of course the answer was that I was incorrect and they were correct but the ears of all the 5150 players who were modding their amps and experiencing the difference was undeniable. There were also lots of players of all models of PV amps who were finding out that the JJ Electronic tubes sounded better to them than the chinese and sovtek tubes PV uses.
I find it VERY amusing that PV responded to the 5150 bias question for several years by saying it was absolutely not necessary for the best tone and dynamic response and then decided to make the 5150 II an adjustable bias amp as is the Triple X… This may seem very arrogant but I think I may have had an influence. In the fall of 2000 I decided to mod a 5150 to be able to run more than one type of power tube with a separate bias control for the inside tubes and the outside tubes. I had volunteered to host the first Northwest PV gathering and I wanted to have something different to play and for others to play. The 5150ex was born and after trying several tube combination my favorite was running two JJ KT88’s in the outside two sockets and two JJ E34L’s in the inside two sockets. It turned out to be a monster! All of the players who played the 5150ex at the PV bash loved it and were very surprised at the tone and the response. Pic’s were posted on the PV forum and players posted their praise for it. Roger posted that this could not be done, would not work and would cause the amp to blow up in very short order…
Well it’s been four years now and the 5150ex gets about 8 hours of hard use every week. It still has the original KT88’s and E34L’s in it and they have not drifted more than one milliamp. The amp simply screams. It has absolutely no other mods to any internal components other than the split bias mod and the addition of the twin bias meters. There are now four 5150ex amps out in the world and all are in excellent health! There are approximately fifty 5150 amps out there belonging to my customers that have had simple bias mods done and are using Integrated quads and the players love them. On top of these there are another 200 plus amps including Triple X’s, Mesa’s, Carvins and Marshalls using the Integrated quads. We all know that the internet makes the world a VERY small place and if the Integrated quads did not sound good or were causing problems it would be all over the net in very short order so I find it amusing that Roger seems to be the only source for the old “It can’t be done”… Even Myles Rose from groove tubes posted on harmony central several times about the amazing sounds that the Integrated quads provided and the matching was to “medical standards”.
Now I usually wait until the end of a page to quote my most favorite saying of all time but I think it’s appropriate to do this right now so here it is! “Man who says it can not be done should not interrupt man who is doing it.” Well, everyone has opinions on tone which in short makes the world go round, it would be a very boring place if we all liked exactly the same thing, but if it’s one thing I have it’s respect for everyone’s opinion about tone and tubes, there is no right and wrong. I even have a couple customers who request tubes that are way out of match because they like the sound of them, I don’t like the sound of out of matched tubes but they do and that is more important.
In August of 2001 Roger sent out an email to quite a few of the long time regulars which did not set well with them as it was basically telling them that the tubes they liked were “not all that”. Rogers email was posted on the forum and one the internet so now that the gloves are off and Roger has seen fit to attack my business and my creditability here it is.
Rogers email
“I am going to ask you and a few others to cooperate with me. The guitar amp forum is turning into an ad for JJ tubes, which we don’t use anymore for VERY good reasons which I will not discuss here. I have word from higher up, to tone it down or get it off the forum.
I know you guys like those tubes, and Bob is a nice guy and you guys are friends, but give me a break. The same few people are posting every other post about how great JJ tubes are, and what a great guy Bob is. I like Bob too, but enough is enough. I have used plenty of JJs and they ain’t all that! Let’s be real here.
If you like them, fine. If you want to use them and recommend them (and Eurotubes) that is fine. But do it somewhere else (why doesn’t Bob get a forum?), or at least tone it down. I would really appreciate it. Starting next week I will have to be a little more strict about what gets posted. Thanks for your support,
Thank You
Roger Crimm
Regional Service Mngr. Peavey Electronics”
After this happened a lot of the long time regulars were very angry and threatened to leave the forum. I felt responsible for stirring the proverbial dodo so I made a farewell post to lots of good friends and ceased being involved on the PV forum.
Anyway, I will go over the points from Rogers article one at a time.
#1. “Sorry, but this has to be one of the wackiest ideas I have ever seen”. Well I’m sure that this has been said about millions of innovations and inventions. A closed mind will get you know where…. Oh, I forgot to bring up the fact that all of the Mesa Boogie Simuclass amps which are designed to run EL34 and 6L6’s together and are coveted for their tone are just “whacky” aren’t they??
#2. Plate current is not the only thing that matters and well made and burned in tubes will not drift more than a couple milliamps over time.
#3. “Sounds like a good way to move some tubes which you otherwise couldn’t sell to me”. Hmm.. A real insult? Slander? Maybe jealousy??
#4. “Using an “Integrated Quad”, you start out with two sets of tubes, which are already at the extremes of their designed specs.” False, #1 JJ Electronic has strict guidelines for what is acceptable and in spec for plate current and transconductance and the tubes I use in the Integrated quads while not exactly in the middle of their design specs are WELL within tolerance and actually not on the extreme ends. By making this statement Roger is basically telling you that when you purchase tubes from groove tubes that are #1’s or #10’s that these tubes are also of poor quality. If I believed what Roger says then I guess that I should throw out several of my NOS quads of Mullard EL34’s that draw less current than the E34L’s I use in the Integrated quads and those RCA and Philips 6L6’s I have that are hotter than the JJ 6L6GC’s I use in the Integrated quads are also junk…. Hmm…
#5. “This is especially silly if you have an amp which gets most of it’s tone from the preamp anyway.” Once again, HELLO, Roger, are you even taking the time to listen to the difference that power tubes make? Your statement tells me otherwise, or maybe a tin ear??In closing I cannot state that Roger is talking about a set of tubes that came from me that caused a problem in a particular amp but since I am the only tube guy I know of that is doing Integrated quads I do take everything that Roger says as a direct hit to me.
So there you go! Just remember that roger says it can’t be done, it’s wacky, it’s stupid, the sonic benefits are dubious, it’s foolishness, and most of all remember that Roger is the guy who “told ya so.
“So once again I would like to close with my most favorite Confucius quote of all time.
“Man who says it can not be done should not interrupt man who is doing it.”
I invite you to search thru over three hundred of the reviews on my customer review page and do a search for Integrated quads, you will find quite a few. Here are a couple I just received from my customers.. boB
Here is what Steven Frank thought about the Integrated sextet in his Triple Rec along with a few other reviews on Integrated Quads.—–
Original Message —– From: “Steven Frank” <simkinmesiotic@yahoo.com> To: “Eurotubes” <eurotubes@cnnw.net> Sent: Tuesday, January 11, 2005 6:00 PM Subject: Re: Tubes!
once i got those tubes, i played from 10pm til about 3am straight. The sustain, the enhanced pick dynamics, the flexibility of all three channels, the actual now usability of chan 1, the killer gain…. I cant thank you enough for making this all possible. My amp is like a screaming hell beast now. The simplicity of the install was entirely more than worthy of the new amazing tones i can get out of my Triple Rec. It turned from a cold crap sovtek doorstop to creamy ‘satriani meets satan’ beast. I love the enhanced sustain, the amazing new responsiveness when i switch channels, the high high high gain, the chime of the JJ’s, and the warmth added to every aspect of the amp. I dropped these tubes in an WHAMO! i didnt even have to touch a setting, and my amp sounded like something that i dream of in my mind. The sonic possibilities are now endless rather than restrained for this amp. I am a sold out lifetime customer.
Thanks Bob!
—– Original Message —– From: matto To: eurotubes@cnnw.net Sent: Tuesday, January 18, 2005 12:47 PM
Subject: integrated quads
Bob, i’ve had my triple XXX head set up with your integrated quad set since april 2004.I took them out and put the original sovtek 6L6’s just to remind myself how it sounded with them in. I can’t tell in words how much better it sounds with your integrated quads!!! I haven’t had any trouble of any kind.
Thanks, matt.
—– Original Message —– From: “Pierre Veronneau” <pn1@tampabay.rr.com> To: “Eurotubes” <eurotubes@cnnw.net> Sent: Wednesday, December 29, 2004 6:14 PM
Subject: RE: Dual Rectifier Mesa Boogie I just read the article from Roger at Peavey.
As you know, I used your integrated quad in my Peavey XXX combo 2X12 and used two ECC832 to tame the gain.
The original EL34s from Peavey were fine but the gain on the amp was useless after 5. The reverb sounded very good but the clean channel would break up too fast. Replacing the EL34s by 6L6s increased the headroom but the clean channel sounded dry and lifeless.
After installing the integrated quad and replacing the preamp tubes including 2 ECC832, the amp had a better clean sound, a bit more headroom, but still had enough of that rich EL34 sound left to make me happy. The ECC832 allowed us to control a smoother gain curve and made the gain knob actually usable from 1 to 10. This decreased the preamp noise a bit too, noticeable in the living room, but not really on stage.
This XXX combo was a very good amp, out of the factory, but for the little extra money involved, your tubes made it into an excellent performer with a bit more tonal variety.
The retubed amp performed flawlessly for nearly a year before we sold it.I always appreciate your instructions and recommendations. You always provided us with appropriate information an never pressured us into buying anything from you.
Keep up the good work,
A satisfied repeat customer, Pierre Veronneau
Here is a copy of Rogers Article:
Integrated Quad ( an article by Roger Crimm )
Sorry, but this has to be one of the wackiest ideas I have ever seen. I know there are a lot of guys who are doing this, and there is at least one tube supplier who seems to think this is a good idea. I tried to stay silent on this one, after all it’s your money. The theory here is that they pick a set of EL 34 and a set of 6L6, which draw the same exact amount of natural plate current. The danger here is in the assumption that plate current is the only spec that matters, and that the tubes will not drift from these specs as they age.
Sounds like a good way to move some tubes which you otherwise couldn’t sell to me.
Using an “Integrated Quad”, you start out with two sets of tubes, which are already at the extremes of their designed specs. That is my primary objection to this idea. I consider the sonic benefits dubious, considering the potential problems you may run into. Once these tubes are subjected to wear and tear anything can happen. I prefer tubes falling into the middle range of spec for that particular tube. That way, you are still ok as they age and slide one way or another.
Every engineer (Including the guys around here who design the stuff), and every master level tech that I have approached with this idea either thought it was the stupidest idea they had ever heard of (a quote), or simply just laughed out loud. This is especially silly if you have an amp which gets most of it’s tone from the preamp anyway. I have had a few guys come through here recently who fell for this particular sales pitch. Everything is ok at first, then you run into problems when the tubes drift away from spec. I was recently involved with servicing a Peavey Triple XXX, which had suffered from this particular bit of foolishness. The complaint was noise, low gain/output, and overall crappy sound. The owner had put an integrated quad in a few months back. All was well for a month or so, but then the amp just lost it.
He brings it in, and sure enough, the only thing wrong with the amp was the tubes. The bias measured WAY off, and couldn’t be brought to spec with the tubes that were in there. The two EL 34s I pulled out of that amp have to rank among the worst set of tubes I have ever seen that would still actually function. They aren’t even close to a current match, they rattle worse than any EL 84 I have ever heard, and are microphonic as all get out. Compounding the problem, the preamp tubes he had in there were no better. They were low in gain and the amp sounded muffled and flat even after we cured the other stuff.
Replaced the crappy tubes, and the amp came back to life. Guy left with a big smile on his face, and promised me he wouldn’t make that mistake again. He got lucky this time, no other damage done (other than to his pocket book).
Yes, I know some of you are doing this with no problems. You are pushing your luck I say, and remember who told ya so.
“Roger Crimm”
A 2014 update:
So yes, while Roger along with all of his “engineer” friends laughed and called all of us stupid and idiots for mixing different pairs of tubes, it has been a pleasure to get so many positive comments from those of you who have experienced the expanded tonal palette of Integrated Quads. Your kind words about the tubes and this page are very much appreciated!
I do find it odd though that over all these years there have been no amp failures and the number of our returning customers using Integrated Quads just seems to mysteriously keep growing. Thanks Roger!
.boB
PS; my 5150ex which has been running Integrated Quads since 1999 is still going strong. A pair of JJ KT88’s and a pair of JJ KT77 reside in it now. It still has the stock tranny’s and screen grid resistors. A nice amp (thanks PV) and a real dragon slayer with these tubes, we just shook the studio with it a few minutes ago!
