Hey guys,
Recently got into messing around with my 2350. Basic facts to start out:
She gives off a high pitched noise at idle and also when the bass hits.
At the 3 minute mark there is a rattle from the other amp I have attached to the box.
My quick research is leading me to think it is capacitor whine, but let me know what you guys think.
[YOUTUBE]2350 - YouTube[/YOUTUBE]
Recently got into messing around with my 2350. Basic facts to start out:
- Had multiple PPI serial numbers, must have been sent back to PPI to be repaired a couple times
- Broke the warranty seal to open her up for these pictures
- Pulling just over 3 amps idle
- Still gives off whine when RCA leads are disconnected
She gives off a high pitched noise at idle and also when the bass hits.
At the 3 minute mark there is a rattle from the other amp I have attached to the box.
My quick research is leading me to think it is capacitor whine, but let me know what you guys think.
[YOUTUBE]2350 - YouTube[/YOUTUBE]
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An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
It could simply be a noisy transformer (which isn't really a problem).
Do NOT operate this amp without having the transistors clamped down. When you reassemble it, you need to clean all of the old heatsink compound from all components, insulators and heatsink and reapply new compound.
Do NOT operate this amp without having the transistors clamped down. When you reassemble it, you need to clean all of the old heatsink compound from all components, insulators and heatsink and reapply new compound.
Ok, is it common for a "noisy transformer" noise to go along with the music? is there anything I can do to fix this?
I already have some kapton tape I ordered as an insulator. What is the best way to clean off the old compound? Also, is there a special kind of compund I should buy for the new stuff?
Thanks.
I already have some kapton tape I ordered as an insulator. What is the best way to clean off the old compound? Also, is there a special kind of compund I should buy for the new stuff?
Thanks.
Also, what is the brown crap on the bottom of the board on the some of the solder points?
Do you reccomend me replacing any of the caps?
Do you reccomend me replacing any of the caps?
I recommend Dow Corning 340 for heatsink compound but it's not critical.
Use a piece of plastic or stiff cardboard to clean off the majority of the compound. Rubbing alcohol and a paper towel will work to remove anything that remains.
The noise will sometimes vary with the pulse width in a regulated amp. Load, output level or DC input voltage can cause the pulse width to vary and therefore cause the noise to change.
Use a piece of plastic or stiff cardboard to clean off the majority of the compound. Rubbing alcohol and a paper towel will work to remove anything that remains.
The noise will sometimes vary with the pulse width in a regulated amp. Load, output level or DC input voltage can cause the pulse width to vary and therefore cause the noise to change.
Sometimes slightly twisting or moving the windings on the transformer will work.
Remember... do NOT power up this amp without having all transistors clamped to the heatsink.
Remember... do NOT power up this amp without having all transistors clamped to the heatsink.
Thank you. I am waiting onthe compound, so in the mean time, ill be able to fashion up some clamps.
I am begiining to think this is typical of some PPI amps. I have the same problem with a PC4100. Perry was helping me previously. My toroid seem to be modulated to the music also. Out of frustration I put the project aside for awhile. The last thing I did was to unsolder and tip the toroid up on posts to find the offending area and then coat it with Super Corona Dope (MG Chemicals). I don't suggest this as a remedy. Maybe as a a last resort. As soon as I have it back out I will let you know the outcome.
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