Sound like a fly trapped in my amp

BintyTwanger77

Just recently, I’ve been sporadically getting a strange anaemic buzz sound like a sickly fly coming from my amp. The amp is a 65 Deluxe Reverb Reissue, mostly use the vibrato channel (input 1), and I’ve heard the noise whether I’m plugged in or not. 

Any ideas? 

NB. It’s not an actual fly, I’m pretty sure of that.

SunDevil

Some things to try:

It might be worth looking at the valves - swapping out one of the input, drivers or PI positions on that signal path (maybe swap with unused valves on the normal channel?)

It might also be worth ensuring the jacks for the reverb tank are well connected?

Dominic

loose baffle ?

John_A

Power valves rattling is my guess, how old are they?

BintyTwanger77

John_A said:

Power valves rattling is my guess, how old are they?

Not old at all, amp bought within the last 6 months, not cranked beyond loud-for-home levels.

dindude

Has it had the Marshall mod?

BintyTwanger77

dindude said:

Has it had the Marshall mod?

Nope, all stock, no mods.

dindude

BintyTwanger77 said:

dindude said:

Has it had the Marshall mod?

Nope, all stock, no mods.

You missed my joke me thinks. You’re probably a bigger Marshal fan than me!

BintyTwanger77

dindude said:

BintyTwanger77 said:

dindude said:

Has it had the Marshall mod?

Nope, all stock, no mods.

You missed my joke me thinks. You’re probably a bigger Marshal fan than me!

I'm shit with jokes like that... I've never owned a Marshall and don't think I will. Devoted member of the BF Fender fanclub.

richardhomer

dindude said:
You missed my joke me thinks. You’re probably a bigger Marshal fan than me!

I was the one who ‘lol’d’ it...

dindude

richardhomer said:

dindude said:
You missed my joke me thinks. You’re probably a bigger Marshal fan than me!

I was the one who ‘lol’d’ it...

Shit, does that mean we are on the same wavelength! Or do you just feel sorry for me?

dindude

BintyTwanger77 said:

dindude said:

BintyTwanger77 said:

dindude said:

Has it had the Marshall mod?

Nope, all stock, no mods.

You missed my joke me thinks. You’re probably a bigger Marshal fan than me!

I'm shit with jokes like that... I've never owned a Marshall and don't think I will. Devoted member of the BF Fender fanclub.

It's the way I tell 'em. It's just "anaemic buzz" sounded like a pretty good description of the Marshall tone. Anyway, I'll try not to derail your thread any more!

BintyTwanger77

dindude said:

BintyTwanger77 said:

dindude said:

BintyTwanger77 said:

dindude said:

Has it had the Marshall mod?

Nope, all stock, no mods.

You missed my joke me thinks. You’re probably a bigger Marshal fan than me!

I'm shit with jokes like that... I've never owned a Marshall and don't think I will. Devoted member of the BF Fender fanclub.

It's the way I tell 'em. It's just "anaemic buzz" sounded like a pretty good description of the Marshall tone. Anyway, I'll try not to derail your thread any more!

No problem, I don't mind the odd diversion.

ICBM

@camf has a Princeton which is doing something similar, although it only comes out on certain notes. We haven't completely identified what's causing it yet, but it seems to be coming from the grille cloth along the top edge of the frame under the chassis.

richardhomer

dindude said:
Shit, does that mean we are on the same wavelength! Or do you just feel sorry for me?

Same wavelength - I’ve  never ‘got’ Marshalls....

camf

ICBM said:

@camf has a Princeton which is doing something similar, although it only comes out on certain notes. We haven't completely identified what's causing it yet, but it seems to be coming from the grille cloth along the top edge of the frame under the chassis.

Although @BintyTwanger77 says the noise is still there when unplugged whereas mine is definitely noise related.

ecc83

By "not plugged in" I take it you mean guitar? You do have it powered up?

If the buzz is there with all the pots at zero suspect the PI valve but incredibly I saw microphonic POWER valves for the first time in 60 years when I came back to V amps!

If access is practical when running, a gentle tap of the valves with a pencil should reveal the culprit.

Dave.

Lebarque

Are you using a Metal Zone with it?

ICBM

Lebarque said:

Are you using a Metal Zone with it?

It can't be that or it would sound like an entire nest of very angry hornets .

BintyTwanger77

Lebarque said:

Are you using a Metal Zone with it?

No, but I can dream... *sigh*

BintyTwanger77

ecc83 said:

By "not plugged in" I take it you mean guitar? You do have it powered up?

If the buzz is there with all the pots at zero suspect the PI valve but incredibly I saw microphonic POWER valves for the first time in 60 years when I came back to V amps!

If access is practical when running, a gentle tap of the valves with a pencil should reveal the culprit.

Dave.

Yep, I'm getting the noise when amp is on and plugged in but guitar isn't. I'm beginning to suspect a loose valve.