peavey 5150 sounds bad

[torpedoted]

hey I was talking to my amp tech and he said I could put new transformers in my amp and that would give it more high end. Im guessing that would ad to the treble I dont know but also he replaced the filter caps only in the power supply, do you think replacing the other filter caps would make it sound better?

[axpro]

I think a new set of transformers is WAY overboard for an amp like the 5150. there are other places you could add a bit of brightness to the circuit without resorting to a transformer swap.

What is the history of the amp? was it new when you got it? has it been modded? I only ask cause i know a few people who got me to do tube swaps on 5150's trying to calm down the excessive gain a bit, and most of the guys i knew were trying to warm them up... could be that you got someone's mod???

[torpedoted]

well I bought the amp off ebay from some guy and he didnt say anything about the amp being modded, the only thing he said was he had the tubes replaced and he let the amp sit untouched or not even turned on for 3 years. Now I dont know as far as if it was sitting in a cold damp environment such as a garage or a basement but if thats the case maybe somthing in the amp was really effected by that. My amp tech did look it over and he would have told me if the amp was modded considering he does mods himself. But you dont think new transformers would give it more treble cause I know they do cost like 200 a pop but hey if it makes a big difference as far as overall tone than it could be a good investment. Do you think maybe replacing the other old filter caps give it a brighter tone?

[axpro]

I don't think filter caps are going to change your treble response appreciably.

What are you using guitar wise? listening to some of the songs on youtube, it's not my cup of tea, but since i used to work guitar sales (now i work repairs!!!) I am used to having people come in looking for "the sound"

Understandably, they are using active pickups. and tuning down a LOT. downtuning that much can rob your guitar of a lot of response, especially if you are using light strings. There is a lot of compression on there, and the lead breaks sound processed. the only rig info i can find all points to 5150 type amps, but pod xt's as well. which will explain part of the tone changes.

As tot he transformer? I Truly don't think it is going to be the thing that "clicks" and makes this perfect.

Also, on choice of tubes for the retube. Chinese ax7's in the first stage would probably give you aharder edge to the sound, if thats not what you used already.

[torpedoted]

well my amp tech also told me that yea new transformers would give it more high end but he said the transformers in the 5150 are good. His only beef was the power supply on the 5150. So I will keep the transformers as far as tubes go I just checked out the preamp tubes he put two jj ecc83 tubes on the right side, one jj ecc83 tube on the left side and the two tubes in the middle are jj ecc803 tubes. my old tubes that were in the amp were sovtek. I guess it does make a difference with pickups cause my lespaul with emgs sound the best with the peavey 5150, my other two guitars sound kinda flabby compaired to the lespaul. I have an ibanez with dimarzio d sonic pickups and I have a dean dimebag guitar with bill lawrence 500xl pickups. well like I said if it comes down to it im going to save my money and get an engl fireball cause I think thats the tone im looking for

[Steve Conner]

I think Peavey made changes to brighten up the tone for the 5150 Mk2 and onwards. I agree that swapping transformers is a waste of time/money. If your tech really knew what he was doing, he could snip out some little capacitor somewhere and give you all the ear-bleeding treble you wanted.

I'd suggest contacting Jerry at FJA Mods for advice. He sometimes drops by this forum.

FJA Mods

5150 VS 5150II < his explanation of differences between the 5150 and 5150 2

[torpedoted]

So if I do get the other capacitors replaced that would give me more treble. My tech just so you know didnt tell me I should get new transformers he just suggested that I could but overall he told that its just a waste of money and that the transformers in the 5150 are good, he looked at my other capacitors and said that they are still good but hey if getting new replacement capacitors will give more treble than I might just go for it.

[JerryP]

Don't touch the transformers, total waste for what you're looking for. Dump the JJ 12AX7's. I don't care for the JJ 6L6's either, but they should work OK. I would try some new Mullard 12AX7's or Sovtek 12AX7LPS in the preamp. If you like the bright buzzy tone have the bias set on the cold side. I usually bias 5150's 28-30 ma per tube.
Jerry

[Steve Conner]

he looked at my other capacitors and said that they are still good but hey if getting new replacement capacitors will give more treble than I might just go for it.

I don't think there's anything wrong with your amp. It's probably sounding the way a 5150 Mk1 was designed to sound. The other ones that you heard and liked better were probably Mk2s, 6505s, or whatever: Peavey changed the circuit to give the later models less gain and a brighter tone, as explained on the FJA Mods site.

So by "snip a capacitor out" I don't mean remove a faulty capacitor, I mean modify the circuit to filter off less high end.

Jerry has a point, the JJ 12AX7s are supposed to be quite smooth and dark sounding, and if the amp was lacking highs then this choice of tubes would only make it worse.

[axpro]

As is usual, Jerry and Steve have it down.
You seem to be confusing modding the circuit, with replacing a faulty component. Without hearing a sound sample, we can't be 100% sure, but i do remember my 5150 being a little dark and overly gainy.

Transformers are a waste of money for this project, and i don't know if an Engl is going to fix your problem either. Trying a preamp tube in pos 1+2 that is known to be a little bright might be your thing.

As for the changes to your amp. I am not sure what all would be needed (been a long time since i looked at the schematic) but even changing out the slope resistor in the eq will give you a big change. or go old school and add a bright cap!

it's going to take you (or your tech) some trial and error. to mod it for brightness, and then let you hear the changes. and undo/change values.

[torpedoted]

well I try some new preamp tubes, I guess this amp just doesnt have the tone im looking for but hey guys I want to say thanks for all the info on the 5150 it helped me alot.

[axpro]

ROFL!


DON"T GIVE UP!!!!!!!

try some new tubes, something a little brighter, but as a few have said, modding that amp doesn't NEED to be a huge undertaking. changing a single resistor (like the slope resistor in the tone stack) will make MASSIVE changes. I don't reccomend going crazy rebuilding it from scratch with all the best parts, but subbing out a part or 2 is realtively easy, and reversable.

[torpedoted]

well for now ill keep what I have in their but later on in the future I will try out new tubes and changing out a resistor or two Im sure my amp tech can do it he actually did amp repairs for hawthorne heights so Im sure he knows what hes doin. I think the problem is with me ive been playing those line 6 amps for so long that I dont know what real tube tone sounds like. But hey man thanks again seriously I really needed all this info otherwise I probably would have done somthing stupid like selling the 5150 or what ever. but yea thanks again

[C.N.]

I know this thread is several months old, but I really have to add here…
I AM HAVING THE EXACT SAME PROBLEM AS TORPEDOTED!!! Every single symptom is exactly the same as he has described.

The presence only responds when cranked and the highs and upper mids are not as clear. The amp sounds scooped and not very articulate. Basically, the sound isn’t anywhere near as “present” or “forward” sounding as a 6505+ in the store running through the exact same cab. I actually did a side by side comparison at guitar center just to be sure!

I also have to run an EQ pedal to try to make up for this difference, but I still don’t get good results. The EQing tends to make the sound harsher and I still don’t get the amp to sound as forward.

****Sorry but I don’t believe any of the suggestions or input so far will work or have any bearing at all…***

To add, I have owned this 5150 for nearly 10 years. My situation is also similar in that I let the amp sit for several years (always indoors and in air conditioning; however, I live in Florida, so the humidity is vicious even indoors).

It used to sound waaaay different. It was much brighter and present such as a 6505+ is. Maybe the character was slightly different than the 6505+ due to the different circuits, but let me tell you… The difference right now is so far off it’s unbelievable. It’s not like a 5% … 10%... or 20% difference... it’s more like a 50-60% difference that it’s almost a completely different beast altogether.

I have tried to replace the power tubes AND the preamp tube TWICE! Mullards, Tung Sols, Gold Pin Tun Sols, Shuguang Chinese, RUBY, JJ’s – THE WORKS!
In-fact, changing the tubes hardly makes a sonic difference at all! I would consider it a 2-5% change in the tone. Also, running my Maxxon VOP9 in front of the amp barely causes a tonal change. It only increases the gain. Moving the tone knob from far left to far right should have a much larger effect on the sound, but barely anything happens. It’s as if something is choking the amp from singing the way it used to.

The only possible solution anyone has offered is the bias change/mod, but given the extent of trying out different tubes, I don’t think that it will make much of a difference since I should have been in the ball park of the intended bias/tube combination at some point. NO LUCK!

The only think that I can think of is that one or multiple components are damaged. This could be from corrosion or the output transformer or something being damaged.

Anyone have any other ideas? This particular amp is very historically valuable to me so I cannot toss it and get another one. I might just break down and contact Peavey.

Sorry for the caps here and there... Just getting kinda emotional about this problem

[CoopDaKill]

I know this is a very old thread, but here’s a (most likely) simple fix. Spray some DeOxit D5 contact cleaner in the FX loop jacks, and all other jacks. And take a 1/4” cable plug and work it in and out of every jack. The contacts get corroded over time. I’ve owned my 5150 head since they first came out. Bought it new. And I have to do this a few times a year. Same symptoms. Loss of gain is my first issue. Hell I sold a 6505 head once with same symptoms, because I thought it needed recapped. lol