No sound in left cup

[Doltero]

Hello crack heads,

Just purchased a very clean bottlehead with the speedball upgrade, it worked beautifully with my beyer t1 and hd650, well if you forget the fact that it took roughly 10 minutes to warm up and get rid of the hummming sound in the right cup (which I'm not sure if its normal). Anyway, and then I decided to turn it off. Waited a couple hours and turned it back on (Forgot to unplug my hp during power on-off process as stated by the seller but nothing about this seem to be necessary from what I gather with my research) Anyhow, now after the hummming process I only get sound in the right cup, or in both if I don't plug the 1/4 inch all the way down but with poor quality...

The crack was built in 2013 by an engineer and I tried moving all the wires and every joints are rock solid. Does it have something to do with the tubes?

much love, and thanks, I did not have much time with it yet but it seemed a massive upgrade from my objective2

edit: I just noticed the input tube (2a07a) is not on the list https://bottlehead.com/smf/index.php?topic=663.0 [nofollow]

[Doc B.]

We try our best to advise sellers to give buyers a copy of the PDF assembly manual when they sell a kit, assuming that the seller is not going to offer you tech support. In that case I'll give him the benefit of the doubt and also assume that he is maybe a railroad engineer rather than an electrical engineer.  If you have that manual you can use the test procedures in it to check the voltages and from those we could help you sort out what is going on.

For starters pull the tubes out and reseat them, then try turning it on again. If you are lucky that might solve what appears to be a bad connection. You are probably reading 12AU7A printed on a tube where the lettering is partly missing. I might guess that if it is a tube issue that would be a preexisting problem that the seller would have informed you of. So that would leave a bad connection somewhere besides at the tube pins as the most likely scenario. We can sell you a new manual download for $15 that has the test procedure and other information to help you troubleshoot the amp. Eileen and I are away at some functions this weekend, but we can set that up for you early next week. Contact Eileen at queen at bottlehead dot com and she can help you out with purchasing the manual.

If you would rather have us take care of it for you you can use our repair service

https://bottlehead.com/?product=repair-service

[Doltero]

We try our best to advise sellers to give buyers a copy of the PDF assembly manual when they sell a kit, assuming that the seller is not going to offer you tech support. In that case I'll give him the benefit of the doubt and also assume that he is maybe a railroad engineer rather than an electrical engineer.  If you have that manual you can use the test procedures in it to check the voltages and from those we could help you sort out what is going on.

For starters pull the tubes out and reseat them, then try turning it on again. If you are lucky that might solve what appears to be a bad connection. You are probably reading 12AU7A printed on a tube where the lettering is partly missing. I might guess that if it is a tube issue that would be a preexisting problem that the seller would have informed you of. So that would leave a bad connection somewhere besides at the tube pins as the most likely scenario. We can sell you a new manual download for $15 that has the test procedure and other information to help you troubleshoot the amp. Eileen and I are away at some functions this weekend, but we can set that up for you early next week. Contact Eileen at queen at bottlehead dot com and she can help you out with purchasing the manual.

If you would rather have us take care of it for you you can use our repair service

Amazing, thank you for the thorough reply. I will check with the seller if he still has the manual or else I will contact the queen. 

[Paul Birkeland]

I only get sound in the right cup, or in both if I don't plug the 1/4 inch all the way down but with poor quality...

If you only plug in the headphones part way, you can send the right channel to both the left and the right drivers. 

[Doltero]

If you only plug in the headphones part way, you can send the right channel to both the left and the right drivers.

oh I see, hence why it sounds weird

[Alonzo]

...waiting on the railroad engineer riot with popcorn...

[Doc B.]

My brother drove trains for years, so I have practice abusing railroad engineers.