Thin sound, some crack noises, and the right channel is barely audible [solved]

[xiawei]

I just finished building my new crack! However, when I couldn’t wait and turned it on, the sound is very thin, with some crack noises, and the right channel is barely audible. It’s much worse than just directly plugging it into my macbook pro headphone jack! 

The resistance check all passed with almost exactly the same values. But the voltage check all showed negative values with very close values? Is that possible? Also there were several things I wasn’t sure about during the building. One is that the power switch is not the same as pictured in the manual, I’m not sure if I put it in the right direction. But I doubt this could affect the sound.

Second thing is about the direction of the capacitors. Which are the 220uF/250V and the 100uF/160V ones. I don’t understand what the “striped side” mean? Sorry English is not my native language.  For 220uF/250V, does it mean the side that has grid grooves on the root of the lead? For 100uF/160V, does it mean the side that has the shorter lead?

Sorry for writing so much, I was desperate to find it our but can’t find answers from this forums.

Thank you very much for your time!

[Paul Birkeland]

Hello Xiawei,

If you are not getting the correct voltages, then do not plug your headphones or any source into the Crack.  (That is what the voltage checks are for, they are a safety precaution)

The striped side of each capacitor is the side that has the marking running along the capacitor.  (See image)
(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fwww.haydnallbutt.com.au%2Fimages%2F43_electrolytic_capacitor.jpg&hash=3262f1cec5bf66434e92b894847e00519be23540)

If you have negative voltage values, you may need to reverse your meter probes. 

If the right channel is barely audible, there is likely a voltage that is incorrect or a bad solder joint somewhere in the circuit.

Sincerely,
Paul

[xiawei]

Thank you very much for the quick reply! The probes of my meter were connected correctly. Do you think the voltages could be all negative from some errors made during the soldering? All the values are indeed very close to what were written in the manual.

I'll double check the capacitors. Can't wait to get off from work. this is really addicting 

[Doc B.]

Did the tubes light up?

[xiawei]

Did the tubes light up?

Yes, they both light up. Just the smaller one is not as bright as the bigger one. Also the two red LEDs are lighting too. Does it sound like I made reversed capacitor(s)? If
I did, could the caps already been damaged? Sorry I know nothing about electronics.

[Doc B.]

If the LEDs are lighting up then the voltages mustd be reading positive, not negative. If the test leads can be unplugged from your meter, maybe they are reversed at that end? If you can post the terminal numbers and the voltages you are reading here we might be able to figure out where the problem is.

[xiawei]

Problem solved! I accidentally forgot to trim the lead from the cap connected to 7U, which touches B1. Can't believe I did that!

I trimmed it and beautiful music flew into my headphone.

Thanks for the lightening speed response! What a great experience here!

Have a great weekend!