slight popping sound in aksa 55

zachslc · « **on:** 1 Aug 2004, 09:18 pm »

I have just assembled my second pair of AKSA 55s. They tested fine and worked beautifully right out of the gate, but I have noticed that one channel makes a bit of a "pop" every few minutes or so. It is not cyclical or volume dependent. It is not so much a problem as a mystery to me. I have tried switching channels in the PS and switching transformers and the same board still does it. Any ideas? Thanks.

Malcolm Fear · « **Reply #1 on:** 1 Aug 2004, 09:24 pm »

It's not a washing machine or fridge type noise?

zachslc · « **Reply #2 on:** 1 Aug 2004, 09:33 pm »

That is what I thought at first and that is what it sounds like, but it is only in one channel of the new amp and not at all in the identical old amp. since I have changed everything around and the sound follows the same circuit board I am pretty convinced it is independent.

AKSA · « **Reply #3 on:** 1 Aug 2004, 10:34 pm »

Zach,

Try running the iron over and refluxing the input capacitor, diff pair and voltage amplifier. Also include R1, R2, R3 and R4.

Cheers,

Hugh

Lost81 · « **Reply #4 on:** 2 Aug 2004, 12:31 am »

Cold solder joints are one of my nightmares.
Everytime I connect and disconnect the spades to the AKSA boards, I hear this crinkly sound (I try to be as gentle as I can be by holding the corner of the PCB also, so that it doesn't flex too much).

I have taken to putting ProGold on the connectors so that they slide on and off easier.

Speaking of solder.
I wished I used the solder Hugh supplied from the get-go.
It would have made the construction of the PCBs 50% easier (I swear!).
In my limited experience, the only solder that works better is the Cardas solder. It melts at a low temperature, and it flows like water.

Never tried WBT's proprietry solder though.... Anyone?

Good luck!

-Lost81

zachslc · « **Reply #5 on:** 2 Aug 2004, 04:10 am »

Thanks for the replies. I did what I should have done before posting--ran the iron back over all the critical joints. The noise seems to have gone away. Thanks again.

Lost81 · « **Reply #6 on:** 2 Aug 2004, 11:39 pm »

Quote from: AKSA

Try running the iron over and refluxing the input capacitor, diff pair and voltage amplifier. Also include R1, R2, R3 and R4.

How sensitive to heat are the input capacitors, diff pair, and voltage amplifiers?

I got a little 2 second distortion (20 minutes into playing from one amp during a 2nd round of testing yesterday).
Should I do this too?

I don't want to fry something from heat damage unnecessarily.

Cheers,
-Lost81