my trilogy squeels

[Davey]

:o  :o  :o


when i turn the amp up (both gain and vol) the trilogy starts to squeel abnormaly =/

not something i like.

could it be from the sheer volume of volume, it's squeeling, or something else?

now, i havent got the amp insanely loud, but it's pretty loud, for home use.
i'm guessing it's microphonic feedback, cos it squeels all of the time, i'm not playing (even during playing, when i'm not hitting strings.. at a point, when the signal gets too low, it starts squeeling)

any pointers, ho to make it go away?
the warpig is dead quiet though

[Fourth Feline]

Two or three things come to mind Davey:

1)
A microphonic pre-amp valve. they do tend to oscillate internally if going a little 'dicky'. If so a gentle tap on the culprit should stop/start the 'whistle'.

2)
The EQ on the amp may need a slight adjustent to compensate for the specific acoustics of the smaller room. Our sound man used to turn up all the tone controls on the PA till the tone sounded nice - but was just beginning to feedback. He would then back off the lows, mids and highs a little (one at a time) - till he found out which frequency band was overly sensitive to microphonic feedback in the given room.

3) To identify it as pickup/amp feedback (or not) - turn round with your sides or back to the amp and see if it fades. If it seems to remain constant and seems to have 'a mind of it's own' - then a pre-amp valve on the blink is more likely.

Hope that helps.  

 :D

[Davey]

Two or three things come to mind Davey:

1)
A microphonic pre-amp valve. they do tend to oscillate internally if going a little 'dicky'. If so a gentle tap on the culprit should stop/start the 'whistle'.

2)
The EQ on the amp may need a slight adjustent to compensate for the specific acoustics of the smaller room. Our sound man used to turn up all the tone controls on the PA till the tone sounded nice - but was just beginning to feedback. He would then back off the lows, mids and highs a little (one at a time) - till he found out which frequency band was overly sensitive to microphonic feedback in the given room.

3) To identify it as pickup/amp feedback (or not) - turn round with your sides or back to the amp and see if it fades. If it seems to remain constant and seems to have 'a mind of it's own' - then a pre-amp valve on the blink is more likely.

Hope that helps.  

 :D

thanks.

it isnt the amp feedback, as it's constant, no matter where i am..

but if it's a microphonic tube, wouldnt the pig squeel too?

[dave_mc]

^ yes. it sounds like it's microphonic.

another thing that might do it (though it's unlikely) is if the actual pickup isn't sitting in the guitar solidly and is able to vibrate (i.e. if the screws holding in the pickup aren't holding it steady enough).

Though I suspect it's more likely to be microphonic.

[Fourth Feline]

... If it is a microphonic tube, the Pig would not be part of the cause/effect chain. As the valve would be oscillating internally and generating it's own whistle down to the other valves, even with the guitar unplugged. If in doubt tap gently with the side of a plastic pen and it will crackle / whistle and then stop etc.

 :D

[Davey]

^ yes. it sounds like it's microphonic.

another thing that might do it (though it's unlikely) is if the actual pickup isn't sitting in the guitar solidly and is able to vibrate (i.e. if the screws holding in the pickup aren't holding it steady enough).

that was the case with the SD JB i had in there before.
but might be with this one too, since it's sitting on the last thread, as the screws are too short

Though I suspect it's more likely to be microphonic.

can't hurt to try both

[dave_mc]

ah, forgot about this! did the TS squeal with your old amp?

[Davey]

ah, forgot about this! did the TS squeal with your old amp?

not that i know of.. but lately i didnt try it very loud.. i'll report about that tomorrow

[TwilightOdyssey]

Could be a shielding issue ... single coil pickups ... computers close by ... powered speakers ... lots of volume and gain ... not a good combo!!

[Davey]

Could be a shielding issue ... single coil pickups ... computers close by ... powered speakers ... lots of volume and gain ... not a good combo!!

the comp wasnt turned on at the moment.. and i left the room too, just to be sure it's not some interference, near my desk

[FELINEGUITARS]

I would try the longer mounting screws and put some foam under the pickup too Davey to see if it goes away.

If it still occurs - maybe shoot Tim/Steve an email or PM

Microphonic feedback can be a real bitch
It seems so much worse when playing in a small enclosed space as there is nowhere to hide.
Many of the players that suffer from it are either playing at home (loud or with mega gain) or in a smallish rehearsal room

The symptoms do seem to be less when they get on-stage in a bigger space.

We do a fair bit of wax potting of pickups (as does Tim and the BKP guys)

[Davey]

it's not a tube, that's for sure now.

i think it is the fact, that the pup isnt rock solid in the cavity

[WITH FULL DISTORTION]

Complete!
Q:p

[WITH FULL DISTORTION]

davey,please, send some pics right on the spot of the problem
i´m fiting my trilogy too and i´m anxious to see if i´m fitting it right or wrong.
JP
hope you fix this problem as soon as a rabbits $%&#.
ahahahahahahha

[Davey]

what do you need pics for? you cant see anything.







oh cr@p.. i just made an order @ thomann and didnt add the screws for the trilogy!! eep..