Bottlehead Crack 1.1 OTL Does it pan? [resolved]

[jlaba92]

Hello everyone,
I recently assembled my Crack 1.1 OTL and it sounds great. The only issue I am having is that when I try to pan anything within a DAW the headphones do not reflect the changes. When I pan hard right the track continues to play in both L and R. When I pan hard Left the audio cuts out completely. I repeated this with my monitors and the panning works. I am running my DAW to a Focusrite scarlet, then the headphone out from the Scarlett is going stereo L and R input of Crack 1.1 OTL. Any ideas?

[oguinn]

Try a different source (like a phone into the RCAs) to see if it’s a wiring issue or something with the DAW

[bernieclub]

Sounds like you may getting one channel through both inputs.   Make sure the jack is pushed all the way in.

[jlaba92]

I tried using alternative sources and only pan hard left cuts off audio completely. I think its wiring with the unit, but that sounds exhausting to troubleshoot....... I just don't understand. The fact that I can hear audio perfectly in both L and R is fine, only when panning comes into factor the audio gets messed up.

[Paul Birkeland]

Can you post some build photos?

[jlaba92]

Is there any specific area of the board that I should focus on when taking pictures?

[Paul Birkeland]

The volume pot, input wiring, and output wiring.

[Doc B.]

You need to isolate where the problem is happening. You should probably test the Focusrite headphone jack with headphones plugged in directly to verify that it pans correctly. If that headphone out pans OK do some tests of the individual channels of the Crack. Just run signal into the right channel input of the Crack (no cable connected to the left input) and see if it plays only on the right side. Then move the signal cable to the left input and do the same test on the left.

If the problem is isolated to the Crack you should look at your wiring of the input jacks, the volume pot and the headphone jack to make sure nothing has been wired to the wrong terminal. It sounds like you maybe have the two channels shorted together at the Crack headphone jack and maybe an open at the left input jack.

[jlaba92]

I narrowed it down to the Crack. I am going over the instructions again to see what I did wrong. I uploaded some pictures as well.

[jlaba92]

When I plug the Right RCA cable in, there is audio on Right only. When I only plug in Left RCA only there is no audio. When I plug both L and R there is stereo output on both L and R. Also, I tested the Focusrite alone and it is able to pan properly.

[Doc B.]

Are you sure that when you have left and right working that it is stereo and not just mono (right) playing on both channels?

Try swapping the cables at the inputs of the Crack. See if the dead channel moves with the left cable.

[Paul Birkeland]

Some general build problems that you have revolve around how you're making your connections.  When the manual says "attach", that means to poke a lead through and at least bend it up against the terminal.  This is explained in bright red text on page 20.  I would go through your amp and remedy this.

You also have lots of long leads poking out of terminals.  Often this happens when builders don't have proper side cutters. 

Can you post your voltages on terminals 1-10?

[Paul Birkeland]

When I plug the Right RCA cable in, there is audio on Right only. When I only plug in Left RCA only there is no audio. When I plug both L and R there is stereo output on both L and R.

It's hard to tell from your photos, but do you have the jumper connected between the upper and lower levels of the volume pot?

[jlaba92]

Are you sure that when you have left and right working that it is stereo and not just mono (right) playing on both channels?

Try swapping the cables at the inputs of the Crack. See if the dead channel moves with the left cable.

in

I plugged in each RCA cable individually again. Now I notice a faint sound coming from L when a cable is plugged in L only. This occurs when either L or R RCA cable is plugged into L input of Crack. This is leading me to think stereo works, it is just some kerfuffle of my amateur soldering.

[jlaba92]

sorry for the poor quality