Bottlehead Forum

Bottlehead Kits => Crack => Topic started by: revolverxz on May 02, 2017, 05:50:01 PM

Title: Crack producing noise? (not from headphone)
Post by: revolverxz on May 02, 2017, 05:50:01 PM
Sometimes I can hear the crack (I think it's the power tube) making a hiss type of noise. I can easily hear it when I move my head close to the amplifier, but sometimes it's loud enough for me to hear the sound just by sitting next to it. Is it a solder problem or a tube problem?
Title: Re: Crack producing noise? (not from headphone)
Post by: Doc B. on May 02, 2017, 08:15:49 PM
Make sure your capacitors are all mounted correctly, with the stripe in the proper position.
Title: Re: Crack producing noise? (not from headphone)
Post by: revolverxz on May 03, 2017, 07:14:10 AM
I think I have the stripes in the proper position. Here's a picture of the crack
Title: Re: Crack producing noise? (not from headphone)
Post by: revolverxz on May 03, 2017, 07:15:36 AM
I did notice that the 2 brown ones are slightly  touching the wood base. Could that be the source of the noise?
Title: Re: Crack producing noise? (not from headphone)
Post by: Doc B. on May 03, 2017, 07:33:18 AM
No, that's not really a problem. But if they were mounted backwards they could vent, which makes a hissing sound and usually a mess under the chassis. It would be helpful if you could narrow down where in the chassis this hiss is coming from. Airborne amp noises are usually a hum or a buzz from a loosely mounted power transformer or arcing sounds from a loose connection.
Title: Re: Crack producing noise? (not from headphone)
Post by: revolverxz on May 03, 2017, 07:36:34 AM
It sounds like the hiss is coming from the big tube(power tube?). I sometimes hear it on my headphones. The hiss goes away for a few seconds when I tap the chassis or the power tube.
Title: Re: Crack producing noise? (not from headphone)
Post by: Doc B. on May 03, 2017, 08:45:45 AM
OK, sounds like the tube is the problem. Is this a recent build?
Title: Re: Crack producing noise? (not from headphone)
Post by: revolverxz on May 03, 2017, 08:50:46 AM
Yes I finished building it last month (around april 7) and I started hearing a hiss after a week or something(don't remember exact number).