Mark 3 noise and hum

[Fastforded]

concerning noise and hum from the amp...some questions...i got some hum, and it really made me wonder

"how do i determine whats a normal noise or hum and whats bad?" i guess experience...

Should I start by getting a good power conditioner? think one is good to have? i traced my power and it goes from 3 outlets to the breaker. all i have plugged in now is the amp.

and i saw this:

"Mike Soldano suggestion...turn your gain/preamp volume way up, and slowly turn your master/poweramp volume down. If the noise stops when master is turned down, your in luck, preamp(s). If the noise persists, output tubes or worse."

gain/preamp volume is labeled " volume" ? its sets the gain level of the pre amp tubes? like V1 and V2?

master/poweramp volume is labeled "master" ? this controls the power tubes?

and NOW with the guitar and cables disconnected, the amp is pretty quiet with no noise or hum
and in stand-by mode all i can hear is the fan...

plug the guitar in, no hum yet.

seems to be in the pedals or cable... someone once told me wire is wire... i tried to explain its not, but it was useless. I guess thats why he works in a hardware store and I build things...

thanks for any suggestions, going to get 2 new cables for the amp.

thanks

 

[Markedman]

Cables, effects, guitar pick ups, they all make noise. Start with a new, quality cable, I like the Live Wire Elite cables, and just your guitar. If you have hiss, try a different guitar and move the position of the guitar around the room. From what you've wrote, it doesn't sound like it's the tubes, but the tube in the V1 position can be changed to an 12at7 to give the amp less gain, and therefore, less hiss.

 

[Fastforded]

Cables, effects, guitar pick ups, they all make noise. Start with a new, quality cable, I like the Live Wire Elite cables, and just your guitar. If you have hiss, try a different guitar and move the position of the guitar around the room. From what you've wrote, it doesn't sound like it's the tubes, but the tube in the V1 position can be changed to an 12at7 to give the amp less gain, and therefore, less hiss.

Just got 2 new fender custom shop cables 20 and 15 foot

I tried just the guitar and it was clean on the rhythm mode 1 and 2

Ill try with the pedal tonight...

Curious question...seems like my clean rhythm 1 channel is a lot louder than the crunchy rhythm 2 channel... Is there a way to get the clean and crunch channel levels close so it's not one channel significantly louder than the other?

Thanks

Is this normal?

 

[OamrG]

Cables, effects, guitar pick ups, they all make noise. Start with a new, quality cable, I like the Live Wire Elite cables, and just your guitar. If you have hiss, try a different guitar and move the position of the guitar around the room. From what you've wrote, it doesn't sound like it's the tubes, but the tube in the V1 position can be changed to an 12at7 to give the amp less gain, and therefore, less hiss.

Just got 2 new fender custom shop cables 20 and 15 foot

I tried just the guitar and it was clean on the rhythm mode 1 and 2

Ill try with the pedal tonight...

Curious question...seems like my clean rhythm 1 channel is a lot louder than the crunchy rhythm 2 channel... Is there a way to get the clean and crunch channel levels close so it's not one channel significantly louder than the other?

Thanks

Is this normal?

A lot of Mark III's had the issue of severe volume loss between ch1 and ch2. I believe you can send the amp in to Mike and have a mod done where your reverb pot is turned into a ch2 pot, so you can independently control the volumes of the clean and crunch channels. This can't be done on short heads though, only medium and long because the short heads have a different circuitry that doesn't allow for the mod, or something like that. As for the hum and noise, I'm legitimately in the dark. Good luck on your quest!

 

[Fastforded]

Cables, effects, guitar pick ups, they all make noise. Start with a new, quality cable, I like the Live Wire Elite cables, and just your guitar. If you have hiss, try a different guitar and move the position of the guitar around the room. From what you've wrote, it doesn't sound like it's the tubes, but the tube in the V1 position can be changed to an 12at7 to give the amp less gain, and therefore, less hiss.

Just got 2 new fender custom shop cables 20 and 15 foot

I tried just the guitar and it was clean on the rhythm mode 1 and 2

Ill try with the pedal tonight...

Curious question...seems like my clean rhythm 1 channel is a lot louder than the crunchy rhythm 2 channel... Is there a way to get the clean and crunch channel levels close so it's not one channel significantly louder than the other?

Thanks

Is this normal?

A lot of Mark III's had the issue of severe volume loss between ch1 and ch2. I believe you can send the amp in to Mike and have a mod done where your reverb pot is turned into a ch2 pot, so you can independently control the volumes of the clean and crunch channels. This can't be done on short heads though, only medium and long because the short heads have a different circuitry that doesn't allow for the mod, or something like that. As for the hum and noise, I'm legitimately in the dark. Good luck on your quest!

Thanks I have to call and ask. I have the combo so maybe no go on that...
I wonder if it's the speaker.. It's not really any kind of Hum from the amp it kinda hums when you play notes... Almost more muddy as you get to lower notes..


Maybe the speaker is worn or tired ??

Haven't really heard a known speaker going bad...they always sounded good as far as I could tell

Any thoughts?

 

[nor]

Gained up MkIII is gonna make noise. Get a noise suppressor.
Don't make a habit of running yer amp without a guitar plugged in. Kills lesser amp brands. Marks are tough, but the majority of the components in yer amp are decades old. Be nice to it.
:wink:
NOTE: A full recap (replacing all the capacitors) did wonders for the noise floor on mine. $100-200ish.

And, yeah. The volume difference is normal. Remember, we are talking about the worlds 1st 3 channel amp. By the time they worked it out, it became the Mark 4.

 

[Fastforded]

Gained up MkIII is gonna make noise. Get a noise suppressor.
Don't make a habit of running yer amp without a guitar plugged in. Kills lesser amp brands. Marks are tough, but the majority of the components in yer amp are decades old. Be nice to it.
:wink:
NOTE: A full recap (replacing all the capacitors) did wonders for the noise floor on mine. $100-200ish.

And, yeah. The volume difference is normal. Remember, we are talking about the worlds 1st 3 channel amp. By the time they worked it out, it became the Mark 4.

Thanks noted... Caps make that big of a differene?

Gonna get some tubes for it now. Started looking at my
Choices... A lot I think

Thanks for the info

 

[nor]

Dougs Tubes has a nice tube cocktail. Just tell em what you got, he'll tell you what you need.

 

[Fastforded]

Dougs Tubes has a nice tube cocktail. Just tell em what you got, he'll tell you what you need.

Yep I was trying to figure out the different tube choices and how the effect the amp...

Mine have the oem mesa pre amps and sovtek 5881 (not the 6l6) and the valve art el34's

Thanks

 

[tony777]

A lot of Mark III's had the issue of severe volume loss between ch1 and ch2. I believe you can send the amp in to Mike and have a mod done where your reverb pot is turned into a ch2 pot, so you can independently control the volumes of the clean and crunch channels. This can't be done on short heads though, only medium and long because the short heads have a different circuitry that doesn't allow for the mod, or something like that. As for the hum and noise, I'm legitimately in the dark. Good luck on your quest!

You can do the rhythm2 volume mod on any mark III. The thing with short vs medium head is that you won't have any space for the extra knob on a fully loaded short head and you will have to compromise. I removed my direct pot on my black dot DRGX short head. Do a forum search and you will have all the info needed and it's an easy mod if you are able to handle a soldering iron.

 

[Fastforded]

A lot of Mark III's had the issue of severe volume loss between ch1 and ch2. I believe you can send the amp in to Mike and have a mod done where your reverb pot is turned into a ch2 pot, so you can independently control the volumes of the clean and crunch channels. This can't be done on short heads though, only medium and long because the short heads have a different circuitry that doesn't allow for the mod, or something like that. As for the hum and noise, I'm legitimately in the dark. Good luck on your quest!

You can do the rhythm2 volume mod on any mark III. The thing with short vs medium head is that you won't have any space for the extra knob on a fully loaded short head and you will have to compromise. I removed my direct pot on my black dot DRGX short head. Do a forum search and you will have all the info needed and it's an easy mod if you are able to handle a soldering iron.

Thanks I did see a few posts. If I understand correctly I am replacing the r130 resistor with a 250k potentiometer. I would use the direct out potentiometer spot to mount the knob


Although

I did see the hi gain mod and I would like to have that done as well...
Not sure if it can be done to my combo or if it something that can easily be done or best left to the pros...

But tht means I might actually need another spot for an additional potentiometer although like the direct out pot once the volume level is set I don't think I need to less with that much...


Ordering new tubes soon... I was thinking about getting all the caps changed out and maybe the tube bias mod... So she might be going to boogie...

Started planning on building a road case for her travel safety..
Wow can't believe how badass this amp really is...

Heard an old fender reverb last night . Wow.

Not even close