upgrades/mod ???? 5150 content

[ashesofphoenix]

so I keep reading about upgrades and mods for the 5150 heads and I was wondering what everyone here likes? I love my original head, but if there are ways to improve it I'd like to take advantage of it? I'm still new to any internal amp stuff and was looking for clarification on what the changes do to the sound? any input would be great!!! thanks all

 

[JakeAC5253]

I'm a minimalist with the 5150 because I really love the way it sounds and it only needs a little tap to get truly "there" IMO. All you really need to do is put a full round of new tubes in (the 5150's are supposedly really sensitive to tube swaps, so you have lots of tweaking power just from this alone) and replacing filter caps if needed (If it's coming close to that 20 year mark, you should probably replace them. Past 20 years, definitely replace them) The 10pF cap mod from Psychodave's thread is up to taste and whether or not YOU personally think the amp needs it. It kills a lot of the fizz and extra "noise" going on in the circuit at higher gain levels and really sort of focuses the amp a bit especially on the red channel, makes it sound more along the lines of a SLO I think. Just makes the gain and presence ranges more usable and a bit more 'polite' sounding. Really nothing else is needed if you ask me, these are just tweaks and/or maintenance, I wouldn't consider them mods as they don't change the voicing of the amp.

 

[JakeAC5253]

I'm a minimalist with the 5150 because I really love the way it sounds and it only needs a little tap to get truly "there" IMO. All you really need to do is put a full round of new tubes in (the 5150's are supposedly really sensitive to tube swaps, so you have lots of tweaking power just from this alone) and replacing filter caps if needed (If it's coming close to that 20 year mark, you should probably replace them. Past 20 years, definitely replace them) The 10pF cap mod from Psychodave's thread is up to taste and whether or not YOU personally think the amp needs it. It kills a lot of the fizz and extra "noise" going on in the circuit at higher gain levels and really sort of focuses the amp a bit especially on the red channel, makes it sound more along the lines of a SLO I think. Just makes the gain and presence ranges more usable and a bit more 'polite' sounding. Really nothing else is needed if you ask me, these are just tweaks and/or maintenance, I wouldn't consider them mods as they don't change the voicing of the amp.

Ya know, maybe I should change out the filter caps in mine...

Me too Haven't done mine yet, darn car maintenance

 

[155]

just bias mod it thats it,,

 

[droptrd]

I'm a minimalist with the 5150 because I really love the way it sounds and it only needs a little tap to get truly "there" IMO. All you really need to do is put a full round of new tubes in (the 5150's are supposedly really sensitive to tube swaps, so you have lots of tweaking power just from this alone) and replacing filter caps if needed (If it's coming close to that 20 year mark, you should probably replace them. Past 20 years, definitely replace them) The 10pF cap mod from Psychodave's thread is up to taste and whether or not YOU personally think the amp needs it. It kills a lot of the fizz and extra "noise" going on in the circuit at higher gain levels and really sort of focuses the amp a bit especially on the red channel, makes it sound more along the lines of a SLO I think. Just makes the gain and presence ranges more usable and a bit more 'polite' sounding. Really nothing else is needed if you ask me, these are just tweaks and/or maintenance, I wouldn't consider them mods as they don't change the voicing of the amp.

Ya know, maybe I should change out the filter caps in mine...

Me too Haven't done mine yet, darn car maintenance

I was going to do that to mine but I was unable to find caps to fit the board and the chasis. I didnt call Peavey though.

 

[mikehickey]

I like mine stock, I have always been happy with the sound since day one.

 

[steve_k]

The search function is your friend...

viewtopic.php?f=3&t=80183&hilit=5150+mods

what's your favorite OD pedal

 

[ashesofphoenix]

I'm a minimalist with the 5150 because I really love the way it sounds and it only needs a little tap to get truly "there" IMO. All you really need to do is put a full round of new tubes in (the 5150's are supposedly really sensitive to tube swaps, so you have lots of tweaking power just from this alone) and replacing filter caps if needed (If it's coming close to that 20 year mark, you should probably replace them. Past 20 years, definitely replace them) The 10pF cap mod from Psychodave's thread is up to taste and whether or not YOU personally think the amp needs it. It kills a lot of the fizz and extra "noise" going on in the circuit at higher gain levels and really sort of focuses the amp a bit especially on the red channel, makes it sound more along the lines of a SLO I think. Just makes the gain and presence ranges more usable and a bit more 'polite' sounding. Really nothing else is needed if you ask me, these are just tweaks and/or maintenance, I wouldn't consider them mods as they don't change the voicing of the amp.

Thanks a lot man. This is actually exactly what I was looking for. I've never done anything as far as changing caps... can u elaborate on that a little bit? ive modded pedals before, but ive never actually opened up an amp. I would like to cut down some noise and fizz going on but keep the 5150 tone and brutalness the same. sorry im a newb at this stuff

 

[drs448]

i just ordered new tubes from laura(valvequeen) and getting the bias mod
i'll post the results

 

[Black Cat]

Depends on what kind of music you like, and what you're expectations are. Typically when I mod those, I usually reduce low end between the initial gain stages to clean it up a bit/tighten it, I also play around with the supply voltage to the preamp as well depending on what the person wants, as well as increase the value of the screen resistors as just a general maintenance

If you already have it open and the amp is 10-15 years or so, I would also recommend replacing the filtration. The Illinois electrolytics Peavey used for that amp are kinda junky IMHO, and have a pretty big failure rate. You don't have to get anything crazy expensive as a replacement, although good axials are getting harder and harder to find for decent prices.

One thing though, when you do bias up the amp closer to the 60-70% percent max dissipation figure, you will notice a noise increase. That amp sort of rely's on the cross-over notch of the factory ice cold biasing, to cut down on thermionic hiss a bit.

 

[ashesofphoenix]

i just ordered new tubes from laura(valvequeen) and getting the bias mod
i'll post the results

Awesome please do!!!

 

[ashesofphoenix]

Depends on what kind of music you like, and what you're expectations are. Typically when I mod those, I usually reduce low end between the initial gain stages to clean it up a bit/tighten it, I also play around with the supply voltage to the preamp as well depending on what the person wants, as well as increase the value of the screen resistors as just a general maintenance

If you already have it open and the amp is 10-15 years or so, I would also recommend replacing the filtration. The Illinois electrolytics Peavey used for that amp are kinda junky IMHO, and have a pretty big failure rate. You don't have to get anything crazy expensive as a replacement, although good axials are getting harder and harder to find for decent prices.

One thing though, when you do bias up the amp closer to the 60-70% percent max dissipation figure, you will notice a noise increase. That amp sort of rely's on the cross-over notch of the factory ice cold biasing, to cut down on thermionic hiss a bit.

I have never really done any type of maintenence under the hood of an amp before. Mine is a 1994 script 5150. Im sure it needs some help at this point lol. Its def noisier than I like and Im aiming for a "djent" sound... really tight crisp palm mute but beefy for open chords. kinda going for a Periphery/TesseracT type of sound. I prob need tubes too. gotta talk to Valve Queen lol.

Im just so new to any upgrades sorry to sound like a moron

 

[Anonymous]

Depends on what kind of music you like, and what you're expectations are. Typically when I mod those, I usually reduce low end between the initial gain stages to clean it up a bit/tighten it, I also play around with the supply voltage to the preamp as well depending on what the person wants, as well as increase the value of the screen resistors as just a general maintenance

Would someone be willing to be patient and explain to me how to increase the value of the screen resistors on my 5150? Does this have to do with the plate voltage? Hey Black Cat... I sent you a PM and I know you dont get on here that much, but if you happen to see this please PM me.

Does anyone know how to get a hold of him? If anyone knows how to do this, can you please help me out?

Thanks, Chad