SEX 2.1 C4S LED and Voltage problem (Solved)

[mauroj]

I just installed the C4S and only the 2 led on the B side light up. The other 2 on the A side stay dark. Please help. Thanks in advance.

 

[Grainger49]

Jeremy,

That isn't much to go on.  How about you post the voltages that are +/- 15% out of spec?

 

[mauroj]

Terminal 10 and 20 are both at 423VDC. but OA is 315VDC and OB is 315VDC, which are way higher than the suggested 75 VDC. Thanks.

 

[mauroj]

Could it be something as simple as a poorly soldered joint? I double and triple checked everywhere to prevent that. Or a bad transistor, resistor?

 

[Grainger49]

Jeremy,

I don't have a manual for the SEX C4S.  (I work from schematics)  So I can't follow.  But the information you posted should get a good answer from other Bottleheads.

 

[mcandmar]

Can you post pics of the board and install, if its not a bad solder joint it could be something placed incorrectly, or wired to the wrong position.  The fact you get the same voltage (315 instead of 75) on both sides is curious.

 

[mauroj]

I am an idiot. I had the red and white wires reversed on the board but not on the amplifier, so the voltage was going backwards. I corrected my mistake and the voltages are now perfect. I hope I didn't do any permanent damage. Now comes the music portion of the evening. Thanks for the help guys.

 

[mcandmar]

Result, enjoy!

 

[mauroj]

An added benefit to installing the C4S is the lowered noise floor with my Denon D5000. The hum that was there before is almost completely gone. Now I can go without adding the 120 Ohm resistors to the headphone jack.

 

[mcandmar]

Even better