Fresh Crack - No sound from left channel.

[Isak]

I finished building my crack and seemed to pass both resistance and voltage checks (I think). Plugged in my headphones and only got sound from the Right channel. If I unplug the right RCA cable and leave the left one in, I can hear very low music in the right ear, but not the left.

I tried searching for related topics but didn't find anything with my exact problem, but I did try some of the advice given.
I just redid my resistance checks, and everything matched except T13. It never rose until it hit the 270k peak, it kind of fluctuated up and down on my multimeter.
I measured the center pin of the RCA jacks and they were both about 100k ohm.
I measured the tip and ring terminal on the headphone jack and they were 2.46k and 2.47k.
I tried re-doing the soldering on the left center pin, the two white wires on the volume control unit and the white wire on A2.
Both LEDs light up.
I checked the RCA cables, they work. The headphones work when I plug them directly into my computer. (Brand new HD650)

I re-did my voltage checks and the numbers seemed a bit off.

1   79
2   154
3   0
4   154
5   82
6   0
7   99
8   0
9   153
10   0
11   0
12   0
13   153
14   0
15   178
20   0
21   203

A1   82   
A2   0
A4   0
A5   0
A6   79
A7   0
A9   0

B1   79
B2   153
B3   99
B4   82
B5   153
B6   153
B7   0
B8   0

I can take pictures of anything specific if that would help. I appreciate the help!

[Paul Birkeland]

Your voltage at 9 is way off, is the 3K resistor well connected there? (Maybe you have it connected to 10 by accident?)

[Isak]

Your voltage at 9 is way off, is the 3K resistor well connected there? (Maybe you have it connected to 10 by accident?)

http://imgur.com/h12GZVk
It is connected at 9L, I might try to re-solder 9L if that might fix the voltages.

[Isak]

uhh, I tried re-soldering 9L, and now the top of T9 is reading 175v 

[Paul Birkeland]

If the white wire going to B4 is connected to T4 instead of T5, I could also imagine something like this happening, but your voltages don't support that idea.

Can you confirm that you're seeing 3K from terminal 9 to ground?

[Isak]

Sorry for the late reply. I'm in Europe (GMT).

Terminal 9 measures 2.91k ohm, T7 is 2.94

[Paul Birkeland]

It's slightly possible that the 6080 didn't travel well, and that there may be an internal short in the tube.  If you can find a different 6080 or 6AS7 to plug into the amp, that would at least eliminate the 6080 tube as the issue.   

[Isak]

I'm not even sure where to start looking for another tube locally.    the 6080 does seem to glow from top to bottom, if that makes any difference. The 12AU7 on the other hand only seems to have a faint glow at the top. Not sure if that's intended or not.

The tubes were quite well packaged imo. However, 2 of the terminal strips were broken in half, but I just superglued them back together. (I assume that shouldn't cause a problem.)

[Paul Birkeland]

Yeah, the terminal strips shouldn't be an issue.  Your 12AU7 is working quite well by the indicated measurements.

1/2 of the 6080 is also working as specified, and the other half has the correct bias being applied to get the results we expect, but is drawing too much current.  This is confirmed by the shared power supply voltages from both channels, which indicate that about 30mA extra is being drawn.  This could be explained by a short inside the 6080 from plate to cathode, which is very, very rare. 

[Isak]

Well, if it can happen, then it can happen I guess.

Do you have any other ideas on what might be the issue? It's my first soldering project so I just figured that I messed something up, although I never went to the next step without triple checking what went where.

On page 19 in the manual, I connected the power transformer terminal 4 to 14U instead of 22L as suggested. Just something I thought to mention

EDIT: Looking at the 6080 socket, the soldering doesn't look very shiny, is it possible that there is some sort of interference, although I did manage to get voltage readings off the B sockets? Here's a picture of the socket http://imgur.com/Lcp3nnt

[Paul Birkeland]

Well yes, actually, I hadn't thought of this before, but I do have something you can check.

With the amp powered down and the power supply reading 0V, measure the resistance between B5 and B6.  Also triple check that there isn't any conducting debris between those pins.

[Isak]

with the power cable unplugged (been that way since yesterday) it seems to read 00.7 when I measure between B5 and B6, with the multimeter set to 200 (not 200k). Not sure if that reads as  7 ohm or 0.7 .

And there is nothing that can conduct between B5 and B6 (you can see B5 and B6 in the picture I posted above)

[Paul Birkeland]

Yeah, 7 or 0.7 are both equally bad.  This means that the plate and cathode are somehow touching, but without touching the grid.  I've seen similar things happen when the welds fail that connect the tube pins to the tube guts.  To absolutely rule out debris, you can yank the tube and measure the pins themselves.

-PB

[Isak]

I'm not 100% sure what you just said, but I pulled the 6080 out and measured B5 and B6 again, but didn't seem to be able to get a reading. Just, nothing came up.

[Paul Birkeland]

I mean to measure the tube pins themselves, with the tube out of the socket.