weird things happening on 5150

god · #1 10.03.06, 3:44 PM

Some weird things are happening on my 5150, does anyone know what could be causing them?

When I turn the amp on from standby(I ususually give it atleast a minute to warm up) there is a loud static noise that last about 2 or 3 seconds and gradually goes away. Its approx the same volume no matter what channel im on or how loud the channel post volume is on.

When I have the amp real loud and play for more than a few seconds then stop suddenly there is a small, not too loud but noticable pop sound.

Also at random times it seems like my 5150 is missing half of its volume. I will have the 5150 on 10, and our other guitarist amp will be so much louder, like to the point where everyone is asking me whats wrong with my amp. I have higher sensativity speakers in my cab also.

If anyone has an insight to any of these problems that would be great.

thanks

Moo · #2 10.03.06, 4:19 PM

check the tubes

god · #3 10.03.06, 4:25 PM

just got new power amp tubes, does the same thing with these as the old ones.

crimsonsteel · #4 10.03.06, 4:49 PM

are the ohms on the cab the same as the head?

also, maybe its the mod?

Elkvis · #5 10.03.06, 5:17 PM

It is very common on the 5150 series for the effects loop jacks to go bad. put a patch cable from the send to the return jack and see if that solves the problem. the things you have described could all be attributable to a problem with those two jacks.

god · #6 10.04.06, 12:11 AM

Quote:

It is very common on the 5150 series for the effects loop jacks to go bad. put a patch cable from the send to the return jack and see if that solves the problem. the things you have described could all be attributable to a problem with those two jacks.

That did not solve the static noise. It is alittle late to see if it does anything for the popping or drop in volume, but I have a feeeling that all three things are connected.

indytruckboy · #7 10.04.06, 3:44 AM

And I have a feeling it may be your mod. WHy would you want 34s in a 5150?

god · #8 10.04.06, 10:27 PM

Quote:

And I have a feeling it may be your mod.

The mod is just a bias mod. It was done by a professional who now builds custom amps.
It could be the mod, but I do not think it is any more likely than anything else.

Quote:

WHy would you want 34s in a 5150?

It makes for a unique sound.

OWHHROG · #9 10.07.06, 5:55 PM

I was recently looking for tubes and I found information on symptoms to look for before replacing tubes.

It sounds like you need to replace your preamp tubes not the power tubes.

Don't do It yourself take it to a pro.

Hope that helps.

Elkvis · #10 10.07.06, 7:14 PM

there's no reason why he needs to take it to a pro just to replace preamp tubes. they don't need to be biased, so there's no problem doing it yourself.

Sunset_West · #11 10.07.06, 8:19 PM

Quote:

Originally posted by OWHHROG
[B]
It sounds like you need to replace your preamp tubes not the power tubes.
B]

+1. Thats the first thing that came to my mind too. That would also explain why the patch going from the Send to Return didn't help anything either.

Barfly · #12 10.08.06, 7:56 AM

Quote:

Originally posted by Elkvis
there's no reason why he needs to take it to a pro just to replace preamp tubes. they don't need to be biased, so there's no problem doing it yourself.

+1