Amplifier cut outs

[cisc]

Hello glad I found this place hopefully I can get figured out whats going on with my amp.
I have a Crate FXT120, it is about 4 years old.
It is cutting out randomly while I am playing, and I have to hit the top of the amp to get it to come back.
When it cuts out it does not go out completely, it loses volume and distorts the tone. Im sure there is something loose inside. I have taken it apart 2 times and looked for anything loose or anywhere that looks like the solder is broken. I find nothing.
Have any of you experienced this and were able to repair it yourself? any idea what could be wrong?

Im stuck using my toneport and gearbox. I dont like using that unless im recording.
Thanks!
chris

[booj]

Look at it again with a magnifying glass. Check out the input jacks. Check any effects loop jacks. Also see if the filter caps are secure. Re-flow the solder on all that stuff.

[Enzo]

First, take a spare cord and plug it into the effects send jack, then the other end right back into the effects return jack. If this external bypass restores the sound, then the return jack needs service.

If it has a pair of jacks marked preamp out and power amp in, do the same test there.

[cisc]

IT has input, insert, and speaker out.

[Enzo]

OK< then the insert jack. Next time it cuts out, plug something in and out of the insert jack a couple times. Does it wake back up? Or while it is still OK, plug something into teh insert jack briefly and see if it triggers the symptom. The insert jack is the same thing as a pair of effects loop jacks except it is in one jack.

If you were real industrious, you could take a bare TRS plug and wire Tip and Ring together inside, then plug that into the insert. Do not wire them to the ground terminal.

[mac1amps]

If it's a Crate. It needs resoldering (always).

[cisc]

well I checked all the inputs and didnt get it fixed.
What needs resoldering?

[tubeswell]

This would appear to be a solid state amp right? See if you can locate a schematic and layout.

Could be a loose wire - going by the intermittent nature of the problem. Have you pulled the chassis out yet? Check that all the wires have secure connections. Modern PCB amps use lugs to connet wires to the PCB. Check that the wires aren't broken/loose. I fixed an el-cheapo Laney a week or so ago, where one of the speaker wire lugs had gotten so loose it had slipped right off the PCB terminal - how badly made was that?

[mac1amps]

Crates are NOTORIUS for needing resoldering throughout the P.C. board. ESPECIALLY at all jacks, controls, and connector pins. Even those connections that are "intact" are often "cold", which is why I always resolder EVERYTHING when I get one of those in my shop. In addition to eliminating cutting out, it always helps the amp sound its best.

[Enzo]

Yes, resolder the jacks and controls, also resolder all those large rectangular cement power resistors.

[acorkos]

with the chassis out, plug your ipod into the input and start poking around all the components while the music's playing. use a wooden stick.

i would check the largest, tallest, heaviest looking components first....sand block resistors, electrolytic caps, especially those with radial leads standing tall. the loose component will reveal itself with a little prodding.

[schaan]

Crates are NOTORIUS for needing resoldering throughout the P.C. board. ESPECIALLY at all jacks, controls, and connector pins. Even those connections that are "intact" are often "cold", which is why I always resolder EVERYTHING when I get one of those in my shop. In addition to eliminating cutting out, it always helps the amp sound its best.

Joined the forum looking for why my Crate GX60-D cuts out and likely found the answer in 60 seconds of searching. Thanks !!!

I purchased this at a Pawn Broker for my daughter as shes taking up guitar and the Amp just cuts out randomly for very brief periods and Id like to use it for an old Roland D70 I havent touched in years.

Schaan in Kansas