Germanium?

[Tony Hardie-Bick]

On 06/02/2019 05:10, Michael Zacherl wrote:
>>> the original moog ladder filters used germanium transistors, iirc.
>>>
>>> that gives them a lower Vbe of around ~ 0.4V?
>>>
>>> this was mentioned by Uli Behringer, where he was discussing the
>>> circuits in-depth (on a mailing list, iirc)
>>
>> Tony, you got a source for this?

pretty sure it was somewhere on gearslutz, but couldn't find it just now
in a quick search.

>> The presumably oldest type I could find was TIS97.
>> And the patent isn’t specific about the type and make of the transistors.

the patent protected the ladder structure, which works with any kind of
bipolar transistor.

> I did find this from 1965 
> 
> https://moogfoundation.org/wp-content/uploads/462.jpg
> 
> which uses an SFT337 germanium transistor.
> 
> Curious, curious … ;)  m.

the transistors change, but the sound remains.

t :)