AC188 Transitors?

[Leftrights]

I just got some AC188 Transistors (from Jack Orman off Ebay), and I was wondering if anyone had ever tried them.  From what I read they are low voltage versions of the AC128.  Are there any noticable differences in tone? or any other specs?

[Oliver]

I just got some AC188 Transistors (from Jack Orman off Ebay), and I was wondering if anyone had ever tried them.  From what I read they are low voltage versions of the AC128.  Are there any noticable differences in tone? or any other specs?

Hi,

I build a FuzzFace and a Rangemaster with AC188 Transistors.
I dont give much on the Vintage Hype that often is done with
ICs and Transistors - when it sounds good for my taste - its all right.
But if there is an Article on Jacque's pages about the mystery of
the AC128 and its actual produced types - perhaps its interesting for
You.... - just look on www.ts-808.com for his page, and
http://www.geocities.com/stompbox2001/ac128.htm for the AC128 Saga

have Fun

bye
Oliver

[brett]

The AC188 also has a higher range of hFEs than the AC128 (ie from 100-500).  You're probably thinking that's good, but don't forget that the higher the hFE the less treble you'll get out of a fuzzface, due to the low gain-bandwidth product (Ft=1MHz).  If the hFE is 200, you might only get to 5kHz.  250=4kHz.  I believe that's one reason why hFEs of around 100 are desirable in fuzzfaces (ie so they'll at least get to 10kHz or thereabouts).  I think RG discussed something like this in his "Technology of the FuzzFace" article.

cheers