hi
can i use 2sa1708 and 2sc4488 instead 2n5401 and bc547 in this circuit?and use 2sa1708 instead bc557
voltage of psu is +/-45 volts
can i use 2sa1708 and 2sc4488 instead 2n5401 and bc547 in this circuit?and use 2sa1708 instead bc557
voltage of psu is +/-45 volts
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You could but running at +/-45V you could use much better low noise made for audio BJT,s in the long-tail pair.
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why you say those SANYO pair isn't low noise?
which parameter is different from 2n5401/bc547?
Quote:
Originally Posted by duncan2
You could but running at +/-45V you could use much better low noise made for audio BJT,s in the long-tail pair.
why you say those SANYO pair isn't low noise?
Because Sanyo don't class --2SA1708 as "low noise " but as (for )=high voltage switching applications.
ÿþ[url]http://www.DataSheet4U.com - 2sa1708.pdf[/URL]
Normally in cases of BJT,s designed for low noise this is specifically stated in the data sheet or in equivalent books ,at least the 2N5401 quotes a noise figure of= 8.0 db .
As an input pair this can be much bettered .
2N5401 - PNP Amplifier Transistors - 2N5401-D.PDF
Originally Posted by duncan2
You could but running at +/-45V you could use much better low noise made for audio BJT,s in the long-tail pair.
why you say those SANYO pair isn't low noise?
Because Sanyo don't class --2SA1708 as "low noise " but as (for )=high voltage switching applications.
ÿþ[url]http://www.DataSheet4U.com - 2sa1708.pdf[/URL]
Normally in cases of BJT,s designed for low noise this is specifically stated in the data sheet or in equivalent books ,at least the 2N5401 quotes a noise figure of= 8.0 db .
As an input pair this can be much bettered .
2N5401 - PNP Amplifier Transistors - 2N5401-D.PDF
zobel in another board
but i have a question about zobel
i want to use this amp to drive a woofer and tweeter which have a cross over(including capacitor and inductor) like this image
in this situation how should i use zobel and how should be zobel?
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I think duncan might have been referring to BC550C's and 560C's, respectively, which indeed are low noise.
Best regards!