Valve amp help

normal. sometimes I hear a radio like it is a million miles away.
my all valve Fender Vibrolux makes noises. never loud but there.

ah right. I was a bit worried for a second. The noise is quite loud tho. is there NO way to reduce its volume?

Loud crackling and popping noise isn't normal. In an amp that's sat unused for a while, or an older amp, it's often due to the electrolytic filter capacitors in the power supply having their aluminum oxide film on the foil thinned out so current is actually "sparking" through it when the high voltage is applied. That makes loud pops, crackles, and sometimes a "thunder" noise. It may improve after the high voltage has been on the caps for a while, allowing the oxide film to electrolytically re-form, but if it doesn't quieten down they may need replacing. There are other causes of crackling including bad tubes, loose connections, bad resistors, intermittent shorts...

Also, your amp or guitar could be picking up external interference, and you could have a bad signal cable. Does it do it with no guitar or cable plugged into it?

thanks Ricochete.
I was addressing the subtle mumurs and static amps can sometimes recieve and transmit.
a loud pop and crackle is problematic.
I think your ideas are worth investigating.

thanks Ricochet, I think it may be the filter capacitors like you said, cos the more I play it, the less the noise seems to occur. Maybe the amp was in storage for a while before delivery & that was what caused it

Could be. I go around and turn on my valve devices (old radios and such) for a minute every month or two, just to keep the caps formed up.

Ricochet is probably right. When I bought my Hot Rod Deluxe 4 years ago, I think it made a few little pops and crackles at first. But now it is perfectly silent. I also found an old '58 Premier Twin 8 amp at an antiques store and picked it up. It is all original including the tubes and in remarkably great shape. I think this thing spent 40 years in someone's attic. It also made some pops and crackles at first, and some of the pots were a little scratchy. But now it plays fine, just played it a couple of hours ago.

I've just fired up my 1967 Hammond H-182 organ after it's been down for a while. Its caps have gotten pretty noisy, as they have a right to be. I'm going to have to replace them before long.

What brand name is the amp, how old is the amp? I'll agree with the cap's also. Couple of other thing could range from bad pre-amp tubes can also cause a crackling sound sometimes all the time or sporadically. Power supplies can also cause popping or cracking sounds. Popping can almost always be an arcing problem. Also an intermittent breakdown of the output transformer or choke. Resistors, particularly carbon composition ones, sometimes develop internal pops. let add a broken resistor or capacitor or R/C lead/ wire.

You may want to turn all the lights off and in the dark turn the amp on and watch for arcing. " BE VERY CAREFUL OF HAZARDOUS VOLTAGES ". Their just as powerfull as they are in the light.

Joe

its a peavey valve king 212. Its brand new off the shelf.

Im guessin it IS them tubes though, cos the longer I play it for, the less the noise is. also it aint affected by volume. the crackling is the same loudness if the amps on 10 as it is on 2

Tubes can cause crackling, by having high-resistance internal shorts or arcing. Bad resistors can cause it, plate load resistors being especially notorious. Tubes (valves) are in a socket for a reason. You can try substituting them.

The noise being unaffected by the volume control means it's in a stage after the volume pot. That narrows things down a lot.

This looked like a good thread for me to bring up MY problem of late:

I have a Fender HRD that did something rather unusual last night. I was playing along joyfully and after about 4 hours of being on (long jam session at a buddies) the amp was noticably more noisy. Low grade hum. At first I could silence the hum by turning down the volume on the guitar and I thought the axe was the problem. Well after another half hour or so, the noise was much more pronounced and was present when nothing but a cable was plugged in (attached to nothing else).

I then figured that there may be some grounding issue and plugged the amp into other light sockets but the noise persisted. I also noticed that the red power light was rather dim and would flicker from time to time. I turned off the amp, went home and plugged it in there.... Dim light and noise.

This morning I bring the amp into work and plug it in, Light is bright and no noise. I am leaving it plugged in as we speak to see if I can replicate the event (long run time)

If the problem persists, I guess I need to bring the amp into the shop again (I just got it back last week, they changed two of my preamp tubes).

Anyone have any input on what may be going on?

Would it hum without a cable plugged in? Wonder if it'll hum again when you get it back home?