More TSL Whoas!!!!

[SG standard]

hello,

i joined in hopes of finding some solutions to my marshall whoas. everything so far has been pretty helpful as far as tips go but i haven't tried them yet. my setup is a jcm 2000 tsl 100 head on a 1960a cab. i run my pedal board which consists of a podxt live and various other stomp boxes right into the input on the front. i play on the 100 watt channel always unless in a really small venue. and i play on average 3 gigs a week. when i engage the crunch or lead channels there is a loud hiss or hum but playing drowns it out. the clean channel is very quiet until recently. the other night at a gig, the hum on the lead and crunch channels seemed to be louder than usual and when i selected a particular patch in my pod that was set to a rat some noise gate and some delay. which is usuall extremely quiet played through the clean channel was noisy as if i had one of the overdrive channels selected. other pedals on my board were fine though. does this sound like a bad tube or another problem. i am an experienced electronic tech but i am new to tubes and tube amps. i know its not my sg or my les paul they are fine through other amps. if it is a tube can i just change it out or should i do the whole byass thing and if so where can i find a guide for that seeing as how i have never performed a bias adjustment.

any help is much appreciated.

SG standard

[Ptron]

Use the process of elimination, my dear Watson. Does the amp make noise with nothing plugged in? does it make the noise with just the guitar plugged in? Does it make noise with only pedal A? pedal B? A different cord? so on and so on.

All that said, if a noise happens only with certain settings on your pedal, then that noise isn't coming from your amp (Your amp may have it's own noises, though). Are sure it isn't your everyday high gain noise? With high gain settings on your amp, not to mention your fx, you're taking every bit of noise your pickups pick up, effects create, and poorly sheilded cables absorb, and amplifiying it hundreds of times.

Also, was your gig at a bar with neon signs? Those are notorious noise generators.

[SG standard]

My cords are all good and on the gain channel it is your normal everyday high gain hiss but i usaull don't have it on the clean channel with that patch. yes i was playing at a bowling alley and i don't know whether or not there were neon signs or not but i have a gig tonight at a church and im gonna see if it is still doing it or not. is it better to run my effects through the effects loop?

[bob p]

if you suffer from the woes of channel hiss, the first thing i would to is get rid of all of your effects. if you still have hiss in a specific channel, swap-out your preamp tubes. give that a shot and report back to us.

[Amp Kat]

I agree with the fellows above that process of elimination is your best friend. As for the effects loop time based boxes work the best in the loop and an EQ but gain devices work best in front however if your loop jacks are corroded or making bad contact a small guitar cable plugged from send to return will work until you can fix them if, you like the pedals in the front better. After changing tubes you may want to take the guitar signal out of the send jack and route that to another amp input or return of another amp. If the problems continues at least you know it's in the preamp and you can eliminate everything after the return in.

[Ptron]

Turn your all your guitar volumes all the way down when you're getting this noise. What happens?

Also, you call it hum in one post and hiss in another. They are different things with different causes. Hum, buzz and hiss are the most common categories of noise. Would you describe it as one (or maybe some combination) of these?

[SG standard]

ok i've done some testing with all things considered. i would best describe it as a buzz not a hum or hiss. if i plug straight in to the input from my guitar and switch to the crunch or lead channels there is a high gain buzz because my gain is at 8 or 10 depending on which channel. i have learned to accept this because it has always been there and i know it will never leave. it was when it started on the clean channel that i was loosing my mind over. the other night at the gig, however, it was back during sound check so i stepped on the expression pedal of the PODxt Live, which i have assigned to volume, to put it in the heel down(silence) position and i heard a pop. suddenly the noise was gone, so i popped it again and it reappeared. then once more and woudn't you know it, it dissappeared. so far it has not come back but i know if i get a little too physical with the volume pedal, it will prbably be back so i keep that in the back of my mind.

now as far as the effects loop goes, i have heard that it is better to run your effects through it and your distortion/overdrive pedals through the front input. i know that this is especially true with delay because if i turn on my delay while on the crunch or lead channels, it sounds as if i am playing in the grand canyon after the walls have been freshly decked out in tile! i use the PODxt Live mainly for effects but i do use some of the distortions within it as well, although my main distortion is the amp's crunch and lead channels. should i run this through the loop or the front input? other than the PODxt Live, i have 6 other stompboxes, a wah and the marshall footswitch on my board(i know what you're thinking and yes, my pedal board is huge-40" x 34"-overkill?.........absolutely!!!! te he he). 5 of the 6 stampboxes are overdrive or distortion and the other is a chorus. can you run a wah pedal through the loop or should it be run through the front? will the volume pedal work through the loop? any suggestions on how i should route my effects? also, the PODxt has noise gate built into it which works like a champ.

thanks for all the help.

[bob p]

ok i've done some testing with all things considered. i would best describe it as a buzz not a hum or hiss.

to me the terms buzz, hum, and hiss all describe different problems. sometimes its difficult to understand what someone's trying to tell you if they don't use the workds i the same way that you do.

... it was back during sound check so i stepped on the expression pedal of the PODxt Live, which i have assigned to volume, to put it in the heel down(silence) position and i heard a pop. suddenly the noise was gone, so i popped it again and it reappeared. then once more and woudn't you know it, it dissappeared. so far it has not come back but i know if i get a little too physical with the volume pedal, it will prbably be back so i keep that in the back of my mind.

if you could describe this a little better, that might help. is this a random event, or does it occur systematically with every other click of the pedal? if it occurs every other time the pedal is clicked, that would sound like a problem with the circuit being switched in and out. if it occurs randomly, you could have capacitance building up on the switch that gets grounded when the device is switched in/out. in that case, a 1M reference of the signal to ground at the input and output might help.

[SG standard]

ok its like im maxing out the potentiometer when i rock the pedal all the way back and maybe going past the last tooth on it and it's making it pop almost causing a bad connection or something and then i do it again and it reverses itself. i think i was just being a little too physical with it because sometimes when i end a song really quickly, i will kind of stomp on it to kill the sound really quickly. i mean im not jumping on it or anything but it's like a controlled stomp and sometimes i might be hitting it just a little too hard maxing out the potentiometer in the expression pedal causing it to do that.

[bob p]

i had a cheap-ass volume pedal that died that way -- if i rolled the pedal back far enough it forced the sweeper of the pot to exceed its rotational limit. that falls into the category of gear that was broken because it was abused.