Nice 50W Amp

[tony]

Oo nga eh.
Kaya lang baka gusto rin ng iba gumawa, pwede kaming magtulungan.

why don't you start another thread about class G? get engel dela pena chime in, lumalabas he is the expert in class G now.....link mo yung threads nya sa diysudio....

[Johannah Aleksandria]

why don't you start another thread about class G? get engel dela pena chime in, lumalabas he is the expert in class G now.....link mo yung threads nya sa diysudio....

Meron na nga akong thread sa Class-G eh, tingnan mo.
It was termed "working".

 

[TinTopHack]

Build and be satisfied.

ito nga yung blameless amp by doug self, nababasa ko ito sa DIYaudio

more info on this amp: http://douglas-self.com/ampins/dipa/dipa.htm#6

It is interesting to note that all the ideas presented by Douglas Self in his Blameless Amp were used by Randy Slone in his amp designs.

[danny]

douglas self and randy slone
are both great audio engineers
too bad, nawala na si randy
sayang talga, nabawasan ng beterano 

[Johannah Aleksandria]

It is interesting to note that all the ideas presented by Douglas Self in his Blameless Amp were used by Randy Slone in his amp designs.

With these ckt sir will it be possible that i would raise the voltage to +/- 80vdc and change the output to a triple stage emitter follower?

[tony]

douglas self and randy slone
are both great audio engineers
too bad, nawala na si randy
sayang talga, nabawasan ng beterano 

there is also robert cordell, william marshal leach, john curl, and walter jung among my favorites....
for tubes, there is norman crowhurst, david hafler, john broskie and others.....

[kulit06]

bakit pa? gawin mo na lang....ikaw ang nangmention, ikaw ang gumawa....

wala bang like dito tulad sa fb?

[j a y k e z]

wala bang like dito tulad sa fb?

pa tag po este pa sub pala hehehe

[danny]

there is also robert cordell, william marshal leach, john curl, and walter jung among my favorites....
for tubes, there is norman crowhurst, david hafler, john broskie and others.....

yup agree.
its just too many to mention sir tony 

[TinTopHack]

With these ckt sir will it be possible that i would raise the voltage to +/- 80vdc and change the output to a triple stage emitter follower?

It will not be a straightforward thing to do. It will require recalc of circuit values. But yes it is is possible.

[Johannah Aleksandria]

It will not be a straightforward thing to do. It will require recalc of circuit values. But yes it is is possible.

I have tried the P3A which is designed for +/- 35vdc to +/-58vdc with yet no problem. But i change the output stage to a force sharing parallel for 4 output tranny and used it to a 4-ohm load, got no problem.
But for this ckt, i am really not sure it wud work knowing the huge increase in voltage. +/- 37 to +/-80vdc.
Plan ko kasi para sa trafo ko na 55-0-55vac.

[tony]

^if you want to use +/-80 volt rails, see to it that the Vceo ratings of your devices are rated at least 170 volts, 200volts rating is even better....

[gorex]

parang may similarity sa dx amp st:

http://users.tpg.com.au/users/gerskine/dxamp/DX%20Blame%20ST%20Schematic.pdf

[tony]

parang may similarity sa dx amp st:

http://users.tpg.com.au/users/gerskine/dxamp/DX%20Blame%20ST%20Schematic.pdf

the difference is in the VAS, instead of a CCS, a bootstrapping network was used as VAS collector load....

variation on the same theme.....topologies are quite easy to figure out.....typical bjt ss amp consists of 3 stages...

1. input stage, can be common emitter, or ltp, can be single ended or complimentary-symmetrical, ltp's can be either npn's or pnp's...loading can be thru using plain resistor, or current mirrors or ccs....

2. voltage amplifying stage or VAS, can be single ended or push-pull, this is the stage that produces the voltage swing sent to the speakers..

3. Output stage, more often than not push-pull, can be a quasi-complimentary or complimentary symmetry....can be a simple Darlington, or a triple Darlington....this is the stage that delivers current to the speaker....

knowing the basic building blocks of a bjt amp, it is easy to see what the designer has in mind in coming up with such a circuit....

[jiggins20]

ilan po gain ng amp?...paano po pgcompute pag meron nkaparallel 330 doon sa 10k feedback resistor

[tony]

ilan po gain ng amp?...paano po pgcompute pag meron nkaparallel 330 doon sa 10k feedback resistor

good question......voltage gain = R8/R9 = 10000/500 = 20 at midband,
the corner frequency formed by the shunt leg of the feedback network R9/C2 = 1.45hz, http://www.sengpielaudio.com/calculator-RCpad.htm

the R30 in series with C7 has a corner frequency of 32mhz......i am not sure why the designer chose this value, the fT of the output devices are at best 2mhz...but at 20khz a 15pf cap has an impedance of about 530k so that we can ignore it...http://www.kusashi.com/reactance-c.php

[gorex]

Thanks Sir Tony plus 1 .yung sa P3A same procedure din sa pag compute ng gain sa feedback? at yung frequency?

[tony]

Thanks Sir Tony plus 1 .yung sa P3A same procedure din sa pag compute ng gain sa feedback? at yung frequency?

thanks, same din ang computations for gain and frequency, you can use the links i posted to calculate on your own.......

[???]

Makikibasa uli.

[jiggins20]

maraming salamat po sir tony...