Mesa Boogie TT800 hum

[agedhorse]

I'm glad to see this was easily rectified. I've got a Mesa M6 Carbine and PH610 but I've been looking to switch to the subway series (maybe the WD800) but I definitely have some concerns about the reliability of the amps, mostly due to a bad experience with the customer service for my M6 Carbine when I bought it used so I'd definitely like to not have to deal with that again.

Understood, that’s one reason I was brought on board to design the Subway line.

The MOSFET amps were a vision of an earlier design team, based on new lateral FET devices that unfortunately underwent multiple revisions and changes of manufacturers as the lateral technology evolved. The amps evolved as the devices evolved, but ultimately the technology just wasn’t reliable enough and the designers ended up trying to hit a moving target (which unfortunately they missed at times).

Because of this, the Subway amps were designed with reliability as one of the primary goals. There were several in depth discussions here on TB about this very subject before the D-800 was introduced.

The results of the Subway amps, their reliability and the model evolutions have been discussed here on TB very transparently.

 

[jeff7bass]

Sounds like a fan.

 

[agedhorse]

Appears not to be a fault with the amp after all, based on the OP’s additional information.

 

[Al Kraft]

Sounds like a fan.

That's what we all suspected at first until the OP tried another outlet in his house....amp noise gone, but some household electrical wiring/outlet troubleshooting is likely on the agenda in near future.

 

[jeff7bass]

That's what we all suspected at first until the OP tried another outlet in his house....amp noise gone, but some household electrical wiring/outlet troubleshooting is likely on the agenda in near future.

No I meant he's a fan of the amp....

 

[Jon McBass]

Before I contact and test Mesa's post Gibson buyout customer service, I thought I'd throw this video up for a reality check. Bought this used late last year, and it was pretty dead quiet. But, a couple of days ago, I fired up the TT800 and (to my ears) a loudish hum started happening. Nothing effects the hum, it's there even with nothing plugged into the input jack.

Check it out... @agedhorse

Gibson bought Mesa/Boogie?? Nooooooooo! Is this going to be another CBS buys Fender? Fender buys SWR? Marshall buys Eden? Tell me they’re not going to kill Mesa/Boogie!

And if they do, will that make my pre-Gibson D800+ a collector’s item?

 

[NeonVomit]

Maybe it was humming because it didn't know the words

 

[Dp1363]

Before I contact and test Mesa's post Gibson buyout customer service, I thought I'd throw this video up for a reality check. Bought this used late last year, and it was pretty dead quiet. But, a couple of days ago, I fired up the TT800 and (to my ears) a loudish hum started happening. Nothing effects the hum, it's there even with nothing plugged into the input jack.

Check it out... @agedhorse

I just sent my D800+ in for repair for the same problem and it turned out to be the fan.

 

[bassinflorida]

Before I contact and test Mesa's post Gibson buyout customer service, I thought I'd throw this video up for a reality check. Bought this used late last year, and it was pretty dead quiet. But, a couple of days ago, I fired up the TT800 and (to my ears) a loudish hum started happening. Nothing effects the hum, it's there even with nothing plugged into the input jack.

Check it out... @agedhorse

Try attaching a "J" neck to it, somewhere.

 

[Jeff Hughes]

I have owned three used Mesa amps and ne’er a problem have I encountered. Of course, one looks like it has been through the war.

 

[Al Kraft]

No I meant he's a fan of the amp....

...oops! And this is why they say a sense of context is so important when listening to someone...at least I provided a good "bad example" to reinforce that point.

 

[Slevage]

Ok, I was under the assumption that it had been working fine there and something changed with the amp.

If that solved the problem, be sure to let the service dept. know.

One power fault that can cause this is when the neutral and ground are bonded at the receptacle or elsewhere other than at the service entrance.

This happens too often.
Sub panels are often the culprit.
At the receptacle is a bit harder to accomplish, but is often an over tightened Romex connector biting through the neutral and shorting it to the bare conductor.

 

[MultiScaleMale]

That's good to hear. I've read most of the threads about the SW series gear when it comes up and I haven't seen many issues but I feel like I'll always have that worry in the back of my mind unfortunately. Fortunately the Mesa cab I have has always been great and reliable and I love the sound of it.

Nobody starts a thread saying, "Day 837 and my amp is working great. No noises, no buzzes, no hum."

 

[DJ Bebop]

Used mesa subway series heads have a reputation of having issues and/or dying out like that.

Customer service is your best bet unfortunately.

Best of luck!

Perhaps you mean abused and not used?
No indications of what you said are true

 

[agedhorse]

I just sent my D800+ in for repair for the same problem and it turned out to be the fan.

Every once in a while we see a failure of the electronic commutator circuit inside the fan itself. This is common to all DC fans on the market and when they fail the fan still works but can induce noise into audio circuitry. When this happens, we replace the fan.

This is simply a defective part. Every amp manufacturer runs into this problem occasionally and repairs their product under warranty. The difference is that we do this for 5 years since our warranty is longer than most.

 

[N4860]

Nobody starts a thread saying, "Day 837 and my amp is working great. No noises, no buzzes, no hum."

I'm sorry but what is your point? Should one not read threads about gear that I am interested in purchasing?

 

[agedhorse]

This happens too often.
Sub panels are often the culprit.
At the receptacle is a bit harder to accomplish, but is often an over tightened Romex connector biting through the neutral and shorting it to the bare conductor.

The most common causes of current (and this voltage drop) on the grounding conductor is reversing the ground and neutral on a receptacle, installing a jumper on an ungrounded branch circuit from the neutral to ground and illegal bonding of neutral to ground on a sub panel.

 

[MultiScaleMale]

I'm sorry but what is your point? Should one not read threads about gear that I am interested in purchasing?

The point was that negative feedback is 95% of feedback. Don't be so defensive.

 

[DJ Bebop]

Understood, that’s one reason I was brought on board to design the Subway line.

Because of this, the Subway amps were designed with reliability as one of the primary goals. There were several in depth discussions here on TB about this very subject before the D-800 was introduced.

The results of the Subway amps, their reliability and the model evolutions have been discussed here on TB very transparently.

 

[Al Kraft]

The point was that negative feedback is 95% of feedback.

IME you can't argue with that...very few people take time to stop to say thanks or offer a word of encouragement, but most can always somehow make the time to whine on endlessly. Not an accusation, just an observation from my own life experiences.