Various pre valve substitutions failed to rid my Kelly (72 built in kings cross) of the light distortion until I remembered that the only work done on this amp was a good set of JJ power tubes taken from the amp's older brother. Is it possible that the jjs are the problem (no problem in the other amp) or did the amp tech (whose reputation as the best in the county has dropped to one who no longer cares about his work) set the bias too hot? I had the impression that the tech favoured the 80s rock side of things so it could explain the problem.
The amp has two El34 and all I want is clean. I get my drive from pedals hitting the amp.
I guess changing the bias by myself is out of the question.
Comments
Changing the bias yourself isn't too difficult - assuming the amp has an adjustment trimmer, many older amps don't - if you can handle simple tools and are aware of the potential dangers.
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
http://www.vintagehofner.co.uk/selmer/kelly/kel3.html
I found another site (and lost it!) with a user manual that referred biasing to 'qualified personnel' Fair enough. In the link above you can I think make out a bias pre set but I cannot see a cathode I sense resistor?
ICBM is a busy man Luke but if you are prepared to buy a modest test meter and a couple of croc leads, PM me and I will walk you through the procedure. Will need some decent gut shots of amp.
The amps seem to be of Selmer derivation? Perhaps IC could suggest a bias current? I would set for 25-30mA per valve.
Dave.
I'm not 100% behind this amp. As mentioned, I have the amp's older brother, the Kelly sound master which has the most incredible body. The (black) kelly gets close but not enough. It's volume has more control.
From what I understand, the kelly amps are tidier version of seller treble and bass. mine came from a primary school in North london.
Has anyone had any other experience of the kelly amps, specifically the sound master? I would love to be able to bring it as close as possible to the sound master's tone.