Re: Where is Graham's mixer design? (was Re: RAT Tube Mixer update?)

In article <47CFC8E9.87F70BA@[EMAIL PROTECTED]
>,
 Eeyore <rabbitsfriendsandrelations@[EMAIL PROTECTED]
> wrote:

> Ian Thompson-Bell wrote:
> 
> > Ian Iveson wrote:
> > >
> > > The first stage usually is the main culprit, in a circuit
> > > with several cascaded gain stages. But is that still the
> > > case if half way through the circuit the signal is
> > > attenuated to the same level as the input, and then
> > > restored? Is the stage that recovers the gain equally
> > > im****tant?
> >
> > It is im****tant. It's noise and head room performance are particularly
> > im****tant.
> 
> Absolutely so.
> 
> Modern mixing consoles have virtually universally moved from a series of
> fixed gain stages with level controls(s) between them to adjust the
total
> gain to a stage with continuously variable gain. This helps optimise the
> various conflicting parameters.

And a few antique mixing consoles also used variable gain amplifiers.  
IIRC the BBC had some tube amplifiers where a pot with a single 
resistance element, cleverly connected, worked to reduce the amplifier 
gain by increasing the amount of NFB at the same time that the output of 
the amplifier was being attenuated.


Regards,

John Byrns

-- 
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