Bottlehead Forum

Bottlehead Kits => Crack => Topic started by: hpjun on May 30, 2013, 11:06:07 AM

Title: Added speedball and added a hum.
Post by: hpjun on May 30, 2013, 11:06:07 AM

before speedball my crack had a very black background with volume pot maxed out i heard nothing.

I installed the speedball and everything checks out and I noticed an improvement but also added a buzzy hum that gets louder when the volume pot is cranked passed 6 o clock where zero volume is 12 o clock i normally lesson to music at 2 o clock levels.

not sure what it can be. i checked all the speedball joints and they looked very clean.

Also I used the left over thicker wires from the crack kit instead of using the thin ones supplied with the speedball kit not sure if it caused the buzzing.

Title: Re: Added speedball and added a hum.
Post by: Laudanum on May 31, 2013, 12:46:44 AM

I'll let the gurus help with the Buzz.  The included wires with Speedball are teflon insulated, the insulation is thinner but "tougher" and more solder/heat resistant.   The wire itself, I think, is maybe one gauge smaller.  But anyway, I doubt the wire has anything to do with the buzz.

Title: Re: Added speedball and added a hum.
Post by: Paul Birkeland on May 31, 2013, 04:27:50 AM

Are all the voltages approximately in spec?

-PB

Title: Re: Added speedball and added a hum.
Post by: hpjun on May 31, 2013, 07:56:15 AM

I noticed the buzz on the left speaker louder than the right speaker they both have a buzz.

I noticed the left MJE350 transistor is running hotter than the right MJE350.

So I think it could be the transistor or that I am feeding it incorrect voltage.

My dad noticed the phase is a little off. I didn't notice it at first but now I do.

I will make the volt measurements later.

Title: Re: Added speedball and added a hum.
Post by: Paul Birkeland on May 31, 2013, 08:04:40 AM

Also look to be sure both MJE-350's are oritented correctly.

-PB

(But one runnig much hotter indicates that you will find a voltage issue most likely)