Austin Treble blaster instructions - is it just me?

[Ballz]

Hi guys - I picked up the PDF instruxions on how to build the treble blaster from Geofex. Being a transistor newbie (I normally do tube amps), I followed the assembly & biasing instructions (the Rb & Re pots) closely. Couldn´t get any civilized readings (not even in the proverbial ballpark)from the collector voltage tests, tho - until I connected the "boost" pot - THEN everything came to life and worked properly, and I ended up with a Mullard OC44, Rb=33K and Re=3,6K at exactly -7V. ACtually, it´s no wonder - I don´t think the circuit works unless you connect that pot.

The unit works fine now, and behaves just like it should. My question: did I miss something in the manual? There´s no mention of the Boost pot until after the biasing procedure (point 12 in the assembly part of the manual) AFAIK?

Where did I go wrong, since it (the biasing procedure) didn´t work? I could have grown white hair - voltages were like millivolts and no way near what the manual says.. :lol:
Or is it simply a typo/an omission in the PDF?
Cheers /Richard

[R.G.]

If I were a native speaker of US English, you'd think I could write more clearly.  :wink:

You're correct, nothing works until the boost pot is connected. I'll take a look at the language to see if I *really* left that out.

I thought I was being clearer than that... mutter... grumble...

[Ballz]

I just came back from a testing session in the livingroom with the latest build, a 2x10" Matchless Tornado with a Spitfire preamp, and oh man, does this bad boy stompbox whip that amp into submission! Those overtones and that smooooth garbled high end from the Strat.....wow!
:shock:

I guess that settles it - I know what to do with my germanium transistor stash   ...

RG - see what your manual did? I´m hooked - boost pot mentioned or not! :lol:

Cheers /Richard, Sweden

[Fret Wire]

Congratulations on both the amp and rangemaster builds! What input cap sounded good with your Strat?

[Ballz]

Fretwire,
Thanks! I´m still shocked what this bugger did to my amp (which was quite a mean thing by itself)....I noticed the 4,7nF I started out with was a bit bright ion the already bright amp, so I currently have 22+4,7nF in it. WIth that particular amp and guitar, the combination is just right (or maybe slightly on the dark side), but I think I might have to
a) make a "range selector" à la Vox/Matchless with 5-6 different caps - this box will be used on a variety of homegrown amps and a bunch of guitars
b) look for better caps than my current industrial (crappy sounding) stuff. I have some mustards stashed away, and I´m going to try those as soon as I get the true bypass switches from Aron. The box sucks away some highs when not boosting. Small issue, not worth mentioning. :lol:

The Strat I tested just now is a cheapo Squier with Custom Shop Fat 50:s, BTW. Very balanced, and very clear/transparent - worth every penny.

The "range selector" will come in handy when it´s time to test the VanZandts and the humbuckers.

Gotta get back inside to let it rip some more before da government comes home from work :-)


Cheers /Richard

[Fret Wire]

I agree, the Rangemaster sounds great with tube amps. The stock cap value usually is a bit much for a strat. A selector switch is a good idea, lets you tune the pedal for single coils or humbuckers, plus different amps.