[sdiy] mached transistors

[Theo]

On thin ice here cause I never matched all pair my self,
but some pp say ladders with all pairs matched sound better.
Maybe the poles move more evenly, don't know really.

Theo


From: Tom May <tom at tommay.net>

> "Theo" <t.hogers at home.nl> writes:
>
> > Only the pairs have to be matched, the closer the better.
> > For a ladder its enough to have the top and bottom pairs matched.
> > But matching all pairs does give slight a improvement.
>
> Certainly matching the transistors in the top and bottom pairs is
> necessary for minimizing control voltage feed-through, but what does
> matching the other pairs improve?
>
> > Using LM3046 ICs is also an alternative,
> > each IC contains one matched pair and 3 separate transistors.
> >
> > Theo
> >
> >
> >
> > From: Terje Winther <terje.winther at notam02.no>
> >
> > > Hello,
> > > I am measuring some transistors to get "mached transistors" needed for
> > some
> > > VCFs (moog-ladders) and VCAs.
> > > How close do they have to be to be called "matched"?
> > > totally equal? 1% apart? 2% 3-5%?
> > > Also, for the moog-ladder filters; do they have to be matched between
the
> > > ladder "staps", or is it enough to have the two transitors of each
"step"
> > > to be matched?
> > >
> > >
> > > tw.  :)
> > >
> > >
>
> Tom.