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I have a deluxe Fender Hot Rod.
It has started to make a strange constant noise, as if "frying a piece of meat with water" something strange. I send an audio so you know what I'm talking about.
Any idea what it could be ?
Thanks.
https://drive.google.com/file/d/1ggY...ew?usp=sharing
i couldn't get the media to play but from the description, it sounds like bad electrolytic capacitors. How old is the HR Deluxe?
Quote:
Originally Posted by DanTheBluesMan
Hi, friend.
I'll explain what I did:
- I have changed all the valves for new valves.
- I have isolated the audio input in sections, one by one, even isolating the power output.
- I have changed the electrolytic capacitors.
- I have checked the voltages and everything +/- ok.
I assumed it was a preamp issue, but by isolating the final stage, by de-soldering the last decoupling capacitor before the differential valve, it still does it.
I don't know what to look for anymore.
I was able to listen to your audio file. It's really difficult to diagnose problems just by listening, but it "could" be a failing resistor or a bad solder joint. Is the crackling sound constant without an instrument plugged into either input jack? Does the crackling sound increase if you turn up the volume control?
The sound is constant and does not respond to the volume control.Quote:
Originally Posted by Michael Smith
I have also resoldered all the pcb of the amp.
My 1968 Fender Bassman had a similar constant crackling sound, which did not respond to the volume control. I changed all of the filter capacitors, the resistors in the power supply, and all of the electrolytic cathode bypass capacitors and also the bias capacitor and resistor. Now it is perfectly quiet, even using the same old tubes.Quote:
Originally Posted by guajiro2000
I realize the Bassman is an entirely different amp than the Hot Rod Deluxe (and much easier to work on). My 1977 Deluxe Reverb also had a crackling sound AFTER I replaced the capacitors, and it turned out to be a bad solder joint on the eyelet board, where a component wasn't making good contact. If you tap around on your pcb board and it's components with a plastic or wooden stick, can you isolate the noise to a particular area?
Quote:
Originally Posted by Michael Smith
I have tried pressing different areas of the pcb with a plastic stick and it does not respond to any pressure.
I don't know if it could be a leak in a capacitor or maybe some cathode resistance of the power stage, of one of the 6L6.
+1Quote:
Originally Posted by Michael Smith
Also suspect are one or more of the various ribbon connectors that link the amp's stages together. Examine each of them and re-seat any that seem loose.
I've resoldered them all but I'll go over them again.Quote:
Originally Posted by phantomman
I had similar issues several times. my 2004 is still working ok but has been in shop quite a few times.
I can't recall - thinking I had resistor R22 and 23 (maybe) replaced......ceramic resistors if I am on point? It HAD to be at the shop for them to figure out which parts were bad.
Had other things done also.......
when they work they sound pretty good and get it done. when they go south - I would agree with many people that when you have more in repairs than the new purchase......it has outlived its service life.
I had a friend gift me a hot rod dlx that had died. Power transformer and parts on the board had released the magic smoke.
I had another friend who offered to build a different circuit in the enclosure and added a mercury magnetics transformer.
https://scontent-lga3-2.xx.fbcdn.net...Rw&oe=6235E73E
I still have the old one, but this one seems to be a lot of fun and sounds good.
If you have to keep repairing after this - replacing may save you money in the long run.
And to be honest.......as an afterthought - this situation is the topic of some my first post here in 2003 -04-05 I do believe.
hitting the invisible "like" button :D
+1Quote:
Originally Posted by FrankJohnson
Also a factor is the aggravation and embarrassment of having the amp go "tits up" while on-stage at a paying gig. Audiences generally take a dim view of dead air.
EXACTLY........Quote:
Originally Posted by phantomman
I REALLY tried to love the Hot Rod, and like I said - when it sounds good - its on! I like the Drive channel 3/4 up and use the gain to run it clean, or sometimes find that hard driven hair all on it king of gain, and control the output with the Master to keep it in the ballbark....... but at the end of the day, if it doesn't work most of the time for long stretches - its a home use amp - and lets face it......this isn't a bedroom level amp.
the 5E3 sequel in the HRD enclosure sounds good, but is heavy. I knew that going in.....TJ had built a similar version for a Friend, and it still kicks today! (BTW - TJ.....may want to talk with you about full on A2 platform)
There are two cement power resistors on the lower part of the main PCB that have always caused these kinds of problems in these amps:
https://www.smpartizan.com/wp-conten...4-1024x679.jpg
Look for discoloring of the board in this area. Sometimes you can just reflow some solder here, however, I usually replaced them but raised up off the board.