TeleWreck - Liverpool 15 W

[El_Martin]

Hi!

some new (for me) findings...or: getting used to TW style amps

Amp is stable
loud as heck
cleans up well
When volume of the amp is totally down, there's a silent signal of the guitar. Sounds a bit buzzy. crosstalk into gate 3? crappy vol pot?

With vol over 12 o'clock, bass gets muddy/knda farting. Blocking distortion or just the small tubes/lo voltage ps?

Actually I'd would have expected it to have a bit more gain.
Probably misconcentption by me.

Guess I have to work 'round the third gain stage. Or simply try a Sovtek 12AX WA as V1.

Any comments or ideas?

Ciao
Martin
PS: hopefully my boring monologues can be useful for future Liverpool 15W builders

[El_Martin]

Hi there!

...this little bugger drives me mad...

Redid the grounding scheme pretty much like Franchesca.
Now hum is nearly twice as big...10 mV

I'm close to switching back to a single star ground like before.
Currently running new tubes in it, gain should be a bit higher (and hum ).
Btw: Had to insert some more rectifiers, since PT had no CT .
FREDs: UF4007

some bad solder joints?

Any ideas from the more experienced TW soldering artists ?

Ciao
Martin

[riscado]

Glen if you don't mind me asking, which clones are you using?

[El_Martin]

update:

- redid grounding scheme several times, currently like Francesca (again)
- EL84 cathode resistor is 150 Ohms
- added another 22uF to first filter cap (very close to bridge rectifiers, sums up to a total of 55uF 1st cap)
- cut some cables to minimal length, adid bit of lead dressing
(edit: voltages pretty much within 5% according to:
http://www.undustrialdesign.com/guitara ... erpool.jpg)

Now it is actually silent at idle, hiss&hum are OK for the amount of gain W/o master.

Left to do:
optimize tube sets
adjust cap over PI (currently 50 pF )
Eventually check alternative OT(s), loudspeakers
edit: (powerscaling, wooden frontplate&housing for the 19" rack, alternative 3rd gainstage, EF86 input stage, cascode input stage,...)


Ciao
Martin
PS: next TW style amp will be finished in a few days. Will report.

[El_Martin]

Hi folks,

did some kind of wooden plate, for cosmetics

See the open space on top?
Dunno if I put in a fan of a graphics card or fit in some profile to include some LEDs for illumination (blasphemy?)

Ciao
Martin