5150 retubing and tube retailers

The original is only 1/4W from memory isn't it? (I honestly can't remember)

I put a 6k8 in series with a 10k pot from memory, can't recall the Wattages. After some tweaking and burning out Grid resistors, tubes and flyback diodes, I went back to stock biasing. The difference is far from huge overall. If the standard bias is good enough for Mr Sneap, well I am convinced. Have you heard what he can do with a 5150? New Devildriver for instance...........
:headbang:

All those things that failed for you weren't due to the bias mod. Those were more likely caused by tube issues. Where were you setting your bias? I hear a huge difference with the bias mod. The difference you hear will depend on where the tubes you are using are biased at with the stock bias circuit. I have seen amps biased anywhere from 7 ma per tube to 22 ma per tube with the stock circuit. For metal tones I generally bias around 28-30 ma per tube.
Jerry
 
Firstly, Jerry I am not trying to argue with you here (or you Sickan or anybody else for that matter), your experience with 5150/6505 (amps in general) is far more substantial than my tinkering.

I should have been a bit clearer with my earlier post. I was biasing very hot and had 2 grid Resistors fail. I replaced them and then had a Ruby 6L6 fail which was what caused the diode to short.

With the Original fixed bias with a Plate Voltage of 507V I had anywhere between 16mA - 26mA (balanced tubes, I think not) so roughly 8 - 13 Watts. I aimed for around a 60% average after the bias mod, so roughly 35mA or around 18 Watts. Quite a difference numberswise.

I quickly threw the mic at the cab and dialled in a quick tone before the mod and recorded a sample (far from a stellar tone :heh:). After I made the mod (about 1 hour later than the original clip), I reamped the same DI's with the same mic position and settings. I had heard (still do hear) many people saying that the bias mod does amazing things so i wanted to hear the actual difference. Well it was not night and day for me.

Samples and photo's are here:
http://dl.getdropbox.com/u/437070/Bias Mod Samples.rar

Yes the tone isn't great (as mentioned) but it should allow any difference to be heard. Yes, I did fix the nasty looking solder job on the cap :).

Again, Jerry or Sickan, not aimed at you. I just find it interesting when all the "bulletin board internet experts" say things like "Bias mod is a huge improvement" or that "preamp tube Brand A sound hugely different than Brand B"........or the like, without any examples to substantiate, when the differences are in fact subtle. I always A/B between preamp tube swaps, powertube swaps, mic preamp's, etc... so I know what the ACTUAL difference's are rather than suffering the placebo effect, or believe internet speculation, or somebody's opinion that they just read off another bulletin board without any actual experience and claimed as their own. I like to quantify things. I am sure I spend too much time proving or comparing, but at least I actually know what the differences are in the end. Long story short, I try not to believe all the hype. There's a lot of exaggerated bullshit out there. Sure, there may be differences, but sometimes the differences aren't as large as you may have been led to believe.

"Clips or it didn't happen" :lol:
 
Thanks for the clips GH!
Maybe I am biased :)goggly:) but I think the bias clip sounds fuller in some way, if you did a blind test I would probably have a harder time telling which I liked better.
I like both tones btw, what is that riffing? I recognize it but I don't know from where.
 
Thanks for the clips GH!
Maybe I am biased :)goggly:) but I think the bias clip sounds fuller in some way, if you did a blind test I would probably have a harder time telling which I liked better.
I like both tones btw, what is that riffing? I recognize it but I don't know from where.

It's not a Night and Day difference though is it? That is all I was getting at.

Riffs are from Machinated, I think (it's been almost 6 months, can't remember exactly).

In the pics, the 6k8 resistor is inside the heatshrink soldered to one of the legs of the Pot in case you were wondering.
 
It's not a Night and Day difference though is it? That is all I was getting at.

Riffs are from Machinated, I think (it's been almost 6 months, can't remember exactly).

In the pics, the 6k8 resistor is inside the heatshrink soldered to one of the legs of the Pot in case you were wondering.

Absolutly not Night and Day there, maybe Jerry have something with bigger difference - it would be interesting to hear a before and after test by him aswell.

Is there a specific reason why you made mod like that? Are you changing the bias more often than you change tubes?
 
Do you mean why is the pot through a hole in the chassis top? If so, for ease of biasing and safety. Otherwise the amp needs to be turned upside down which can be tricky with tubes and bias probes in it. This way I also have no danger of touching the potentially lethal 500+ Volts present inside the chasis.
 
The only difference that I hear is that the "after bias" clip is slightly louder (which it would obviously be if nothing else in the chain was changed, due to the amp outputting more wattage). Other than that it is extremely subtle.
 
Since I pull the chassis anyway when I set the bias I used a multi-turn mini pot and mounted it to the board.

DSCN0188.jpg
 
The bias mod itself doesn't sacrifice more highs does it? You can always just bias the tubes back to how they were, and the tone should be exactly the same as before, right?

the mod istelf does not sacrifice the highs, running the tubes hotter will since you are removing the crossover distortion. However when you compensate by turning up the presence, the highs that are there will be more musical and a hell of a lot smoother. Not as harsh or brittle.

Is there a specific reason why you made mod like that? Are you changing the bias more often than you change tubes?

*facepalm*

That was the way i was describing the mod and stated to get the larger rotary pots so that you could drill it to the chassis and relieve you from having to take the amp out of the box everytime you get new tubes. Also new tubes or tubes that have never been fully burnt in, like an tubes that is in a stock 5150 will drift bad for awhile and you need to monitor your bias all the time. I had mine set and waited without playing for about 20 minutes, and noticed that still almost 3 days later that the tubes would drift over 100%, and they would even drop down below 50% at times. About a week in they finally settled in one place.

I am a mad man and run mine pretty hot, 70% which would be 42mA at 500 plate volts. Bigger difference in tone, its a little less subtle and more noticable when you get it that high since at that level you have removed all crossover distortion. Couldn't be happier with the tone. JJ pretube biassed at 70%, with my Boss SD-1 the tone is thick and crunchy as hell. Still i need to get the crappy Sovtek 6L6WXT+ out of there and get something better.
 
Tube Amp Doctor 6L6WGC-STR or Tungsol 6L6GC STR. I hate the JJ's.
Jerry

Jerry know's what's up get the TAD 6l6's.

If you're gonna do the preamp to I suggest a sovtek 12ax7 LPS for the phase inverter and filling the rest of the preamp section with 8th/9th generation chinese tubes (shuguang)

If you do what I just suggested and don't like the tone you get you are allowed to come to my house and punch me as hard as you can in my face 12 times.
 
btw I'm begging you, JJ's are decent powertubes (in some amps) but I really really really really dislike them in 5150's.
I would never buy JJ preamp tubes for any amp but would also never buy the JJ powertubes for a 5150.
 
So allright guys, I got the 5150 (signed by Tom in Evergrey, his old amp!) as a graduation gift (or whatever you call it) and it contains Sovtek 6L6 WXT+ 's, I'm thinking of keeping them exept if you guys think they are... bad and can recommend something noticeable better.
The preamp tubes are EH's and I'm interested in changing them, at least have some to test the difference with (the ones I stated earlier in the thread).
 
btw I'm begging you, JJ's are decent powertubes (in some amps) but I really really really really dislike them in 5150's.
I would never buy JJ preamp tubes for any amp but would also never buy the JJ powertubes for a 5150.

i really beg to differ. I have all JJ's in my 5150 preamp section. The amp has serious meat to it compared to the GT's that were in it before. Eh's are too bright and fizzy. Just my opinion though.

So allright guys, I got the 5150 (signed by Tom in Evergrey, his old amp!) as a graduation gift (or whatever you call it) and it contains Sovtek 6L6 WXT+ 's, I'm thinking of keeping them exept if you guys think they are... bad and can recommend something noticeable better.
The preamp tubes are EH's and I'm interested in changing them, at least have some to test the difference with (the ones I stated earlier in the thread).

Damn lucky catch how did you manage to get Tom's 5150? The sovtek 6L6 WTX+ are stock to 5150's they are just meh imo, kind of boxy, don't produce enough clarity and meat in the low end, but they get the job done. EH's are possibly the brightest preamp tubes you can get, although they are of high quality, if you find the amp too bright, you can experiemnt and find what darker tubes match to help balance the amp. I woudn't get the chinese tubes since they are virtually as bright as the EH, you would be better off going the polar opposite and looking into Penta Labs and JJ, Pentas being warmer and JJ's being darker. IF you like the way it sounds I wound't change a thing. That explainsa a lot about evergrey's tone throught most of their albums minus torn, extremely bright, not much bass and real boxy and cardboard sounding (the result of those tube combos), I always remember watching videos of them in the studio and Tom bitching about how the guitar tone sucks lol.
 
I just had a reply from Zing Studio (Adam D's studio) about the 5150 they use on their recordings.

They said each 5150 doesn't sound the same, you have to find a good one ; they generally use stock preamp tubes (Groove Tubes from what he said), then having it biased correctly.

I had JJ tubes in the power section for a while, they are great (lotsa low mids) but do not sound as tight and agressive as SED "Winged C" (love them) or Sovtek tubes. For recording purposes, agressive tubes seem to be the way to go so that your guitars have definition in the high mids and will match in your mix better.
As for preamp tubes, I liked a combination of Sovtek LPS, EH, and Groove Tubes. I'm currently trying a Tung Sol in V1, sounds cool but I want to try an Ei Elite or chinese Shuguang in there.
 
I spent a fair amount of time and effort fiddling with Gian Pyres's 5150
and a big box of NOS tubes, from what I remember the best pre amp tubes
where mil spec Mullard CV4004's and the best output tube's without bias mod where a set of Mesa badged 6L6's that came with a mesa dual rec Paul Allender used, we changed that to Mullard EL34's much better!.
but with the bias mod done on the 5150 I think you really need RCA JAN 6L6 or maybe these:
http://cgi.ebay.com/6-Western-Electric-6L6-Metal-JAN-VT-115-NOS-WWII_W0QQitemZ250438865079QQcmdZViewItemQQptZVintage_Electronics_R2?hash=item3a4f51d0b7&_trksid=p3286.c0.m14&_trkparms=65%3A12%7C66%3A2%7C39%3A1%7C72%3A1234%7C240%3A1318%7C301%3A1%7C293%3A1%7C294%3A50
for metal:headbang:
But also what we didn't try where the fabulous GEC KT66 or Mullard EL34's or Mullard EL37's which would have been very very reliable and sound great with the bias mod.:Smokin:
 
Damn lucky catch how did you manage to get Tom's 5150? The sovtek 6L6 WTX+ are stock to 5150's they are just meh imo, kind of boxy, don't produce enough clarity and meat in the low end, but they get the job done. EH's are possibly the brightest preamp tubes you can get, although they are of high quality, if you find the amp too bright, you can experiemnt and find what darker tubes match to help balance the amp. I woudn't get the chinese tubes since they are virtually as bright as the EH, you would be better off going the polar opposite and looking into Penta Labs and JJ, Pentas being warmer and JJ's being darker. IF you like the way it sounds I wound't change a thing. That explainsa a lot about evergrey's tone throught most of their albums minus torn, extremely bright, not much bass and real boxy and cardboard sounding (the result of those tube combos), I always remember watching videos of them in the studio and Tom bitching about how the guitar tone sucks lol.

They (Evergrey) made a competition when they changed to 6505's last year, which I participated in but didn't win. The guy who won Tom's 5150 already had another 5150 so he put it out on a trading site. I talked to the guy selling it and when I was satisfied I told my parents I wanted it as a graduation gift, and as spoiled as I am - I got it :headbang:
fiddy.jpg


I tested it out in a studio the day before yesterday and I noticed the brightness you are talking about.

I had JJ tubes in the power section for a while, they are great (lotsa low mids) but do not sound as tight and agressive as SED "Winged C" (love them) or Sovtek tubes. For recording purposes, agressive tubes seem to be the way to go so that your guitars have definition in the high mids and will match in your mix better.

It seems like everyone like the SED "Winged C"'s and that's what I'm leaning against now! (Not a big fan of lowmids, big fan of defined highmids :loco:)
Just to confirm it, this is a Winged C right? It says SED 6L6 and on the picture I see some kind of a Winged C :oops:
 
Winged C's and JJ's seem pretty popular choice for powertubes among 5150/6505 users, I think the SED have more popularity though. The SED'd are known for being sharp and agressive and the JJ's have more bass, tighter bass with more low mid warmth without being muddy. As it is obvious I like JJ's becuase the 5150 is naturally a pretty bright amp and i think that JJ's all across the board balance out the amp, enhance the hollowness of nothing in the lower mids, making it warmer without sacfricing the musical highs and without being muddy.

But not trying to advertise them by all means, nor do I beleive they are an end all say all, every tube serves a purpouse and it comes down to which one or which combos work. I think with what you are looking into tonewise, a tungsol in the V1, Shuguang or Penta Labs in the middle positions and a balanced JJ in the V4, with Winged C's. However ultimately it is up to you to test out different tubes and see what works for you, its a trial and error scenario that eveyone has to go through.