Crack heat and noise [resolved]

[Zniper]

Hi everyone, I've got the amazing Crack + Speedball 1.1 for about two months. Everything works fine except the heat (on chassis) is pretty high. I'm sure that I couldn't leave my finger there for more than 2 seconds. I know the amp with tubes generate lot of heat, however not sure which would be the "normal" range?

Another small issue is kind of inconsistent background noise after running it for 3hrs continuously. The noise completely disappears after I turning off > waiting for ~20s > turning back on the Crack. Same phenomenon with different tubes, could it be the cold solder(s) or any possible causes?

 

[Paul Birkeland]

If your voltages are correct then the amount of heat generated by the amp is OK.

The noise you're describing could be environmental, is your Crack near any wireless devices?  It might not hurt to go over the hardware on the amp and be sure that all the screws are tight.

 

[Zniper]

Yeah, all the voltages are in acceptable range.

There are indeed some wireless devices around but I did some tests of moving/disabling those but nothing change. Thing is noise will disappear after a quick reset, and the whole device are still warm/hot.

 

[Zniper]

Hi there, now it has new issue. After normally running (with all LEDs light up) for few minutes:
- There is a loud pop on the headphone and the left channel goes muted
- One LED (at A3) doesn't light up.
- Resistances: Terminals 7, 8, B3, B6 (which should be 2.9K) read */1
- I'm using 220V AC input, the voltages are:
1: 70
2: 211
3: 0
4: 212
5: 205
6: 0
7: 110
8: 0
9: 204
10: 0

OA: 210
OB: 110
G: 0
B+: 205


I'm not sure if I need to replace that LED or resolder the connection points next. Any advice is greatly appreciated.

 

[Paul Birkeland]

The LED at A3 doesn't look to be all the way soldered to A3.  I would try reheating that joint first, then let us know what happens.

-PB

 

[Zniper]

The LED at A3 doesn't look to be all the way soldered to A3.  I would try reheating that joint first, then let us know what happens.

-PB

Thanks much for the advice, I think that's correct as after reheating A3 and few other suspicious ones, the Crack normally works. I'm still keeping an eye on this though.