--Be sure to feed your devices, as
--each added device draws
--addditional current.
This is the part I need to understand
so bear with me - hehe
I'm looking at this schematic for reference.
http://www.aussieamplifiers.com/downloads/AV800.pdf
Do you mean each mosfet draws
additional gate current and
the "bias and buffer" stage needs
to be re-designed to supply more
current to feed the mosfets?
Or do you mean there is so much
input gate capacitance using 50
output stage mosfets which would
cause side-effects when sending
an AC signal which would require the
'bias and buffer" stage to have lower
output impedance to minimize the
effects?
AV800 schematic -
Is potentiometer "P1" in the schematic the bias adjustment?
What exactly am I thinking (lol) ?
Bipolar output stage questions -
Is this true/false statement --
In a bipolar design, the "pre-driver"
stage needs to be "beefed" up
since addition bipolars will draw
more base current so paralling
50 bipolars would be more work
since the pre-drive stage would
have to supply alot more current?
is this correct?
Last question for now ....
I thought mosfets didn't draw gate current so I was thinking that the original pre-drive stage in any
mosfet would be sufficient?
Thanks for any tips/comments,
I'm just compiling data, ideas,
trying to understand basic concepts
before I tackle a project. I built
a monster amp over 10 years ago
from Mark 5 electronics, it was
a 150w mosfet that I "beefed" up
using a 2KVA powersupply, 16 pairs
of mosfet outputs per channel with
240kuf of power supply capacitance.
I didn't really understand what
I was doing, it was more or less
"electronics hacking"... but it worked quite well. I was load testing it with 0.5 ohm load resistors in a bucket
of water - haha!
Also, I did something back then
that was kinda odd. The amplifier
had too much hiss.. what I mean is
when you placed your ear close to
the tweeters you can hear some hiss.
Back then I thought the amplifer had
too much gain so I cheated to reduce
the hiss. I changed the feedback
resistor so there was less gain,
to offest this, I made a single ended input pre-amp circuit using the 5534 opamp with gain = 2 (I think).. This
gave me similar input sensitivity
but with no hiss at all. What exactly
happened here? What is wrong
with doing this?
Instead of blindly working on my
next project, this time I'd like to
better understand on the inner workings of the circuit instead of
"hacking"......