My RG100HT hums quite a bit..any clues???

I really like this amp...despite the fact it has no footswitch and a weird jack for th footswitch that is from HELL.
But I cant do much till I get rid of the hum..any clues?
Its always there..even with no wire hooked up to the input. Even withtthe revrb off.
Anybody go thru this?

might be worth checking the bias, as if it is unequal on the output valves it causes hum

..I never opened it...but it well known to be a SS amp.
But if anyones got another suggestion Im game.

try a noise gate it worked for my amp

The hum is not coming from the input, so a noise gate wont help.
Its internal....so I am not sure what to do.
Anybody else go thru this? What did you do?

It could be the electrical jack that your plugging into. I have the same problem when I use the amp at work, not wiried properly is my guess. :?

nah..it hums wherever I take it.
I used it 3 days ago at a rehearsal (my rack gear is troubled right now)..and it was plenty loud but....still a hum was ever present. My tube gear is less noisy..and that is saying something.

GtrGeorge! said:

nah..it hums wherever I take it.
I used it 3 days ago at a rehearsal (my rack gear is troubled right now)..and it was plenty loud but....still a hum was ever present. My tube gear is less noisy..and that is saying something.

Click to expand...

first off, are your audio cables near an outlet? you can get massive hum if they are too close and your cable is not shielded properly.

is the ground where you live or where your currently plugged into okay?

check the grounding on the amp cord the trace it to the internal for a look if/when you look inside.

try blowing the pots out with some canned air from a computer store. then if that didn't help

try taking apart the unit, but start very slow with just the cover plate. i have never used this particular unit but most rack equipment has a top cover plate for ease or access during the build as they are typically assembled then put in the rack unit case then to a rack holding case during use.

as you do this, use the canned air but just bend the hose down a bit and point it around rather then tip the can and freeze all your internal parts for no good reason i have done this, generally never hurts anything but never a great idea.

then put the unit back together and try again. if then a hum still continues, take the top off again. now this time look around to see if any random piece of "something' might be causing a small short or bridge. maybe a connection has come distant but not completely apart enough to short but just damage the sound quality.

maybe a capacitor is going or a fuse is on it's last leg. check the fuse for sure... lol.

try these things and get back to me.

good luck

Thanks for the suggestions..
I did check my cables and the ground at my outlet is fine.
Now I MUST open the box. But tim,e is tight ,,so I will ahve to wait till my next day off...next week.
Thank you again for the ideas..its a cool amp!

Im gonna get it repaired
know anyone you'd recomend for this job in NY (Im on Long Island).
GtrGeorge

Ferrite Core 1/4" Cord Noise Suppressor

these do work, i have them on everything, including my Tv's and dvd players. It may help your amp, it may not, it helps my rg200es and it also helps everything in my rack, I have them on everything that has a power cable, they are only a couple bucks a piece.

Black plastic enclosed ferrite core for 1/4" AC power cords. Easy to install, simply snap around cord. Helps reduce EMI on AC power lines. Cable core filter will provide common-mode filtering for multi-strand cables and differential mode filtering for single conductors



you may also want to check out a hush IIC or IICX in the FX loop, that also helps a lot but is a pain as i have to turn it down at low volume levels or it will cut off your sustain... turn down the hush,,, here comes the hummmmmmmmm, but not annoyingly so....

Hope that helps.

I still own it..and wish I knew a good repair guy in NY/Long Island..
anybody?????

I had that in my RH150G3. Take it to any electronics place and describe your issue. It's an easy fix, It cost me 80 CAD with tax, so it should cost you $50, all labour.

It's a case ground issue.

Yep, it's most likely an internal ground problem, actually a transistor shorting to ground when it shouldn't be. I had an old Randall combo that did this and it was an easy fix when I found it.

I am getting the amp back in a week or so. I spoke the repair guy today..and I have my fingers crossed.
This same guy just repaired my Ampeg SVT100 combo bass amp. he said the solder joints had oxidized and just needed to be reheated...
doesnt that seem like a "pat answer" to you?
seems that way to me..but what do I know..i am not a repair guy.
So we will see..hopefully this guy knows his stuff and he can fix my Randall RGHT100..its quite a cool sounding solid state head. really is.
i am a tube guy and I am impressed.
George

so they want 175 to fix my randall RG100Ht...kind of a drag. I am not sure if I am gonna go for it. i already have like $125 into it.
I think the repair cost is inflated...i was told it just needs some power caps...That doesnt cost THAT much.
anyone want to buy it? Let me know.
GtrGeorge

Pm'd