HELP!!

[Ace]

OK, I LOVE the tone that I get from my MP-1. The problem is noise. It's as loud as a four-year-old's first trip the dentist. I am planning on getting it modded by voodooamps, but that won't be until March. In the meantime my band can't even talk at practice because of how loud my amp is humming. I have a noise gate in front of it, but that only helps a little, and it cuts off my decay too soon. Is there any temporary fix?

[lerxstcat]

Re: HELP!!

The noise gate's in front of it? Shouldn't it be after it, between the preamp and power amp, to do its thing? Also, what kind of noise gate do you have? If you set the noise gate to a minimal setting and turn your guitar volume down when not playing, seems like that'd help. Are you sure your power amp's not contributing some of the hum as well?

[Ace]

Re: HELP!!

Positive it's not the power amp. If I switch to a clean channel on the MP1 the power amp is silent as hell(it's a 2150). I use an Alesis 3630 for my gate, and if I put it after the preamp the threshold isn't high enough to stop the noise unless I turn the output VU on the MP1 REAL low(like 8 o'clock), which keeps me from being able to crank it.

[Twisteramps]

Re: HELP!!

Have you tried changing out the preamp tubes? If you're not running the preamp full out, try a 5751 instead of 12ax7s, or even a single 5751. It has 70% of the gain of a 12ax7, and is MUCH quieter.

Pete

[Newc]

Re: HELP!!

Have you tried bypassing the 3630? You might have it set too far into the Compression function, or it's crapping out. My MP-1 isn't very noisy at all, and it's unmodded with a 12AX7.

Of course, I run the main Volume knob about 9'o clock on it, and then into another unit which I crank the volume of.

Try turning the MP1's volume down (knob) and the power amp's volume up. Does your power amp have input AND output volume knobs? If so, try turning the MP1 down, and turn the amp's Input volume up a bit (not much), then crank the Output of the amp.

Newc

[Ace]

Re: HELP!!

[ QUOTE ]
Have you tried changing out the preamp tubes? If you're not running the preamp full out, try a 5751 instead of 12ax7s, or even a single 5751. It has 70% of the gain of a 12ax7, and is MUCH quieter.

Pete

[/ QUOTE ]

My next step was to switch out the preamp tubes, I was waiting until I got it modded, but I'm sure I can pick up a pair of 12AX7's somewhere very cheap if not free. I run the preamp about as hot as I can stand the noise, which is about 80%.

My 2150 only has a master VU knob, but the back has a "lo/high" sensitivity switch, which I have in the "Lo" position. I've bypassed everything except the ADA and the power amp before, and it was STILL noisy.

I think it might well be time for new tubes. Thanks guys!!

[RacerX]

Re: HELP!!

Ace, do you have a tube tester?

[Ace]

Re: HELP!!

Nope.

[Twisteramps]

Re: HELP!!

Most tube testers will only show transconductance or shorts... I can only think of one that tests for noise, and those are $599 (vacuum valley tester, I think.)

Pete