Mark IV B head noise - is it normal? needs repair?

[Bobby Marshall]

Just started playing in a band again. Other guitar player says my Mark IV short head makes too much noise and I can't use it at the upcoming gig because the sound guy will go nuts. Needless to say if you are reading this but I am not pretty upset that I will be going to this gig without my Mesa Boogie. I always wanted a Mesa Boogie Mark Series amp and this is my first one. I love it's sound when I am playing.

I figured out the noise was in the preamp (ran effects loop send directly to another power amp and the noise was still there) and replaced all of the preamp tubes. Still had the noise. Used DeoxIT to clean the pots and tube slots per a suggestion on this forum and still have the noise (only much clearer!).

The noise is always there. Reverb on or off. EQ on or off. Even if I unplug the cable from the input. Noise is louder when I turn up treble, switch to rhythm 2, switch to lead.

Is some noise "normal" or should the amp be dead quiet when I am not playing? Should it be dead quiet when no signal is going to the input?

If this is not "normal", any suggestions? There is an "Authorized" Boogie repair shop in Chicago per the Mesa Boogie website but not sure if "Authorized" means I can trust them or if it just means they will charge more for a repair that I may or may not need.

Any help would be appreciated.

BTW - new member but have read this board off and on for several years. Nice to know there are others that love the Boogie.

 

[ToneAddictJon]

Welcome!!!
Try unplugging the fan and see if that helps. How high up do you have your treble?? The treble is like another gain control on the MK IV. I keep mine at 5 or lower and use the geq and presence controls to dial in more high frequencies if needed. Also, try plugging into a regulated power supply (power conditioner) as well instead of power out of an outlet. Power tubes can cause noise as well so if you can replace them that's something else to try. Good luck

 

[eltrain858]

it should be dead freaking silent on the rhythm 1 channel, mine only makes noise on the lead channel with the gain way up

 

[MusicManJP6]

it should be dead freaking silent on the rhythm 1 channel, mine only makes noise on the lead channel with the gain way up

+1!

FWIW, I once had a reverb tube go south on me and it was creating the most aweful amount of white noise, EVEN IN RHYTHM 1!! Needless to say, I was baffled until I found the culprit: The 12AT7 reverb tube...

 

[Bobby Marshall]

Welcome!!!
Try unplugging the fan and see if that helps. How high up do you have your treble?? The treble is like another gain control on the MK IV. I keep mine at 5 or lower and use the geq and presence controls to dial in more high frequencies if needed. Also, try plugging into a regulated power supply (power conditioner) as well instead of power out of an outlet. Power tubes can cause noise as well so if you can replace them that's something else to try. Good luck

Unplugged the fan, no help. I use a Furman Power Pro Rack power conditioner, no help. Power tubes not problem as noise still there if I just use preamp section of the Mark IV and run FX loop send to another power amp. I did lower the treble controls and turned off all the "fat" and "bright" switches. This has brought down the impact of the noise significantly. Probably enough to get by this gig. It still bugs me that the noise is still there. There still must be a problem right????

 

[Bobby Marshall]

it should be dead freaking silent on the rhythm 1 channel, mine only makes noise on the lead channel with the gain way up

+1!

FWIW, I once had a reverb tube go south on me and it was creating the most aweful amount of white noise, EVEN IN RHYTHM 1!! Needless to say, I was baffled until I found the culprit: The 12AT7 reverb tube...

I am using 12AX7s and I replaced all of them and still the noise. I reduced the treble and it hides it well but it is still there. Just doesn't make sense. There still must be a problem that I am missing.

 

[JOEY B.]

Is it a hissing or buzzing noise without anything plugged into the input jack?

 

[fpoon]

Your most likely playing or connected too close to electrical appliances or something is wrong with your house's wiring. Today I moved one of my amps upstairs and it was dead silent on distortion when it usually hisses downstairs close to my T.V etc. Get a noise gate if you can't fix the problem.

 

[ToneAddictJon]

Sounds like tech time to me. Mines dead quiet, and even with high gain on it's not noisy at all. I can't stand excess hiss or noise in amps, if your guitar isn't plugged in and the noise is there it's definitely a tech issue. Good luck, and if you find what it is let us know!!!

 

[eltrain858]

FWIW, I once had a reverb tube go south on me and it was creating the most aweful amount of white noise, EVEN IN RHYTHM 1!! Needless to say, I was baffled until I found the culprit: The 12AT7 reverb tube...

I am using 12AX7s and I replaced all of them and still the noise. I reduced the treble and it hides it well but it is still there. Just doesn't make sense. There still must be a problem that I am missing.

hmm... is that the problem? 12AX7 tube in the reverb position?

 

[Aart]

No, Mark IV B's have a 12ax7 for the reverb, the Mk 4 A uses the 12at7 for the reverb. Yours should work fine with a 12ax7.

I would go to a tech, your amp should be quiet in rhy 1.

 

[Living_justice]

noise gate needed for hi gain playing when loud, but the rhy 1 should be quite loud.

 

[danyeo1]

What kind of guitar are you using? If you're using a Strat with high gain at loud volumes then yeah, you're going to get some noise. If you use a Strat get a Decimator pedal, it will kill all that annoying noise.

If you don't use a Strat, just try another guitar. Make sure your guitar has the ground wire connected to the bridge, if that wire comes loose then your guitar will sound like a waterfall at loud levels with gain.

Also, mid gain adds some noise. But i can turn up my MarkIV without a noise gain at high gain levels and it's tolerable.

Plus, if your other guitar player told you to jump off a bridge would you listen to him? Just asking!

 

[Bobby Marshall]

What kind of guitar are you using? If you're using a Strat with high gain at loud volumes then yeah, you're going to get some noise. If you use a Strat get a Decimator pedal, it will kill all that annoying noise.

If you don't use a Strat, just try another guitar. Make sure your guitar has the ground wire connected to the bridge, if that wire comes loose then your guitar will sound like a waterfall at loud levels with gain.

Also, mid gain adds some noise. But i can turn up my MarkIV without a noise gain at high gain levels and it's tolerable.

Plus, if your other guitar player told you to jump off a bridge would you listen to him? Just asking!

Not off a bridge, no. Some people say being in a band is like being married. It is not quite like that because at least your wife loves you. Bandmates are even harder to work with, especially when you don't have a friendship. This guy has extensive live experience and I trust him when he says the amp is not suitable for our gig. It is a 1,000 seat gig and all our equipment will be mic'd for the house PA.

Different guitars and cables don't effect hiss much. Single coil, humbucker, same hiss. It is even there when the amp is on but no cable is plugged in the input.

I am going to put up another post to see if anyone in my area knows a tech with Mesa experience.

Thanks for the feedback.

 

[Living_justice]

get a ss amp then.

 

[MusicManJP6]

Noise gate is the only way to make your bandmate happy it sounds like. There is going to be some noise from the Lead channel in most cases unless you have perfect wiring in your house. Get a noise gate and be done with it!

My guess is that you will take it to the tech and either it won't do it, or he'll tell you it's 'normal'. Just make sure you aren't sitting too close to the amp when you are diagnosing the noise. It can cause hum/noise if your guitar is too close to the transformer in the amp...

 

[Bobby Marshall]

Noise gate is the only way to make your bandmate happy it sounds like. There is going to be some noise from the Lead channel in most cases unless you have perfect wiring in your house. Get a noise gate and be done with it!

My guess is that you will take it to the tech and either it won't do it, or he'll tell you it's 'normal'. Just make sure you aren't sitting too close to the amp when you are diagnosing the noise. It can cause hum/noise if your guitar is too close to the transformer in the amp...

I will try the noise gate as well for now. I also use a Furman Power Pro to clean up the power. The noise is there no matter how close I am to the amp. And it is there when the amp is on and no cable plugged into the input. Based on that, I don't think it is feedback from the guitar and/or a problem with the cable.

Thanks for your suggestion. Hopefully that will satisfy my bandmate and the sound guy at our gig Saturday night.

 

[Bobby Marshall]

get a ss amp then.

LJ, where's the love?

A solid state amp?? Why not just tell me to jump off a bridge??

Why would anyone on this board want to dump a Mesa tube amp to go solely with a SS amp set up?

Why would anyone on this board bad mouth someone for asking a question about whether his Mesa amp is in need of repair? If you have been reading the other posts, some others on the board seem to agree that there is a tech issue and that there should not be noise even in lead mode.

I will use a noise gate for now but I want my Mesa to be in perfect working condition and it would seem it is not in perfect condition right now. Seems most in search of ultimate tone want the least amount of gear in their signal paths so why not fix the amp so it works properly? I want my amp to scream when I make it scream. It seems that is how they should work, high gain or not.

Hope you can use your Mesa without a noise gate someday.