static/crackling in left channel

[atom631]

It's entirely possible it has to do with the jack. Usually the black wires there are normally the culprit. Maybe try moving them around, adjusting them while the heat is on. Plus make sure all the wires at terminal 3 are secured well.

i reflowed all the black wires, including the LEDs and the switch. no change. also had my wife take a listen to make sure im not losing my mind and she hears it too.

here are some pics. i tried to get as close as possible and capture every joint.

part 1

[atom631]

part 2

[atom631]

part 3

[atom631]

part 4

[Paul Birkeland]

The left RCA jack ground lug and the chassis earth lug by the power entry module do not look adequately soldered, just as an example.

[atom631]

The left RCA jack ground lug and the chassis earth lug by the power entry module do not look adequately soldered, just as an example.

reflowed those 2 connections. pics attached. didn't change anything. then tried to go over a bunch of joints and reflow them and now i actually think it sounds worse. so it probably is something to do with a soldering joint but short of redoing the entire thing, not sure how i can isolate it.

[Deluk]

The last "flow" pic basically hasn't. I use Cardas solder and it flows easily and gives a smooth finish. I use #7 bits in my old Weller solder station. It has no adjustment. If this pic shows a joint similar to others in your build I would say that upping your technique would be a useful move.

[atom631]

Im resurrecting this thread since I never resolved my issue and had just shelved the BHC until now. Id really like to get it working. I added this mod: https://forum.bottlehead.com/index.php?topic=11676.0 and it didnt solve the issue. Snapshot attached.

I was able to grab a voice memo recording of the crackle from my iphone. I held the phone about 1" from the driver. There are no RCAs hooked up to the BHC during this recording. 

[hmbscott]

This looks like a poor solder joint to me. I don't see much of a fillet. It might just be the pic. But if it does accurately capture the joint, I would add solder here until a nice fillet is visible.

[atom631]

I finally solved the issue!!! It turns out it was a bad 22.1K Ω resistor that is soldered to terminals 4 and 5. I replaced the resistor and there is zero crackle, zero static. Dead silence until the music kicks in! I can finally enjoy some Crack! Now Im going to give it a few months and then I will do the speedball upgrade.

I do have a question. I bought the replacement resistor from digikey.  It appears to be rated the same and has the same color banding..but it is considerably smaller. See pics below. Is this OK?

[Paul Birkeland]

It's a funny thing about that resistor, as it dissipates a bit under 1/2 a watt in the amp.  On that basis, you'd want to opt for a 2W resistor for optimal operation (PR-02/RR-02 are good for this).  The resistor we use is extremely conservatively rated, so it won't cause problems.  In practice, what you bought should run just fine for 2-5 years.