#1
Whenever I turn my amp off, it starts to rumble for a few seconds then slowly fades out. It doesn't start instantly, about 2 seconds after flicking the switch and stops after about 3 seconds of rumbling. I've got a HH IC-100 combo if that helps.
#2
Rumbling as in noise or rumbling as in movement?
The information is to vague and open to interpretation.
..I was watching my death.
#3
Rumbling as in noise, also it never changes volume, if i had my amp on 4 and switched it off, then on 1 and switched it off, the volume of the rumble itself wouldn't change.
#4
Is the noise coming from the speaker or the amp in general?
Assuming it's from the speaker, I'm going to try my best in describing this sound:
Is it a sort of "Fffffffffwwp" sound? Is there a pop at the end?
If so, this is completely normal. This would be the capacitors discharging. They still hold a charge much after the amp is turned off, that's why it's not a good idea to poke around inside your amp, most of the time some of the capacitors in an amp will be high voltage.
..I was watching my death.
#5
You can get all sorts of sounds out of an amp when you power down and the capacitors discharge. The FX loop in my amp makes a little descending squeal like a theremin for about 2 secs if I hit standby.
Is this something that has suddenly started to happen that never happened before? If so it may be something minor blown in the power amp. 'Twer it mine I'd be pulling it apart and looking for torched resistors. If you don't know what you are doing, keep your mits out of there.
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#6
Quote by Cathbard
You can get all sorts of sounds out of an amp when you power down and the capacitors discharge. The FX loop in my amp makes a little descending squeal like a theremin for about 2 secs if I hit standby.
Is this something that has suddenly started to happen that never happened before? If so it may be something minor blown in the power amp. 'Twer it mine I'd be pulling it apart and looking for torched resistors. If you don't know what you are doing, keep your mits out of there.


When I turn my EQ off it makes a high pitched almost bird-like sound. It scares the hell out of people at a gig.
..I was watching my death.
#7
i think you'll get a better response if you email MAJ electronic:

http://www.majelectronic.co.uk/

they are just about the only people who still know anything at all about the old HH amps. most people on UG have never heard of them, and know nothing at all about them.

the IC100 is a nice amp though. they need to make more solid states like that.
I like analogue Solid State amps that make no effort to be "tube-like", and I'm proud of it...

...A little too proud, to be honest.
#8
Quote by Blompcube
i think you'll get a better response if you email MAJ electronic:


Hate to break it to you, but he did get a good response here already. We explained what was going on and how it's completely normal(Unless his rumbling isn't from the speakers.).
..I was watching my death.
#9
Quote by timbit2006
Hate to break it to you, but he did get a good response here already. We explained what was going on and how it's completely normal(Unless his rumbling isn't from the speakers.).

that's the key point really. he hasn't necessarily got an answer because both you and cathbard have pretty much just guessed that it's the capacitors discharging, but you don't know if it's a normal thing to happen with the IC100, whether it's actually coming from the speaker, or whether it's always done it or just suddenly started doing it.

besides, MAJ electronic know more about the inner workings of this amp than you do
I like analogue Solid State amps that make no effort to be "tube-like", and I'm proud of it...

...A little too proud, to be honest.
#10
Quote by Blompcube
that's the key point really. he hasn't necessarily got an answer because both you and cathbard have pretty much just guessed that it's the capacitors discharging, but you don't know if it's a normal thing to happen with the IC100, whether it's actually coming from the speaker, or whether it's always done it or just suddenly started doing it.

besides, MAJ electronic know more about the inner workings of this amp than you do


I don't see where else this sound could come from, unless turning off his amp causes a small shift of a tectonic plate.
By the way, Cathbard is a genius. Enough said.

Are you sure there's no Indian call center?
..I was watching my death.
#11
Quote by timbit2006
I don't see where else this sound could come from, unless turning off his amp causes a small shift of a tectonic plate.
By the way, Cathbard is a genius. Enough said.

Are you sure there's no Indian call center?

there isn't a call center if you email them

i'm not knocking anyone's knowledge or anyones suggestions as to what it could be, i'm just saying it might be more helpful to contact the guys who know these particular amps inside out.
I like analogue Solid State amps that make no effort to be "tube-like", and I'm proud of it...

...A little too proud, to be honest.