'Goldmund' don't use baxandall pair, just simple differential with current mirror in VAS like in my http://www.diyaudio.com/forums/solid-state/162081-dc-servo-mosfet-amplifier-13.html but without DC servo circuit.
Hiyass,
Mamak and Chlorofille, welcome aboard, you both from Malaysia too, Mamak you cannot do step down voltage from 230@240 to 110 with this regulator, i`m understand you want to make step down transformer to have 110v, This is not transformer and this is regulator, and i you do that u made very big mistake and smokes generator it self.
You used those words "super baxandall" for VAS on Goldmund.
On the other side I think it's better not to use DC servo if you can, and no cap on feedback either. That's what Luxman and Goldmund also had in common.
Set bias to 100mA, and use this circuit for leds.
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hi apex sir,
is this circuit work with any amp?
for 50vdc rails any changes?
is this method correct?
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.......
hello, What is the + and - of the capacitors 10uf /63v and 1uf /63v
For testing purpose i will be using 37-0-37 v 5 amp transformer, do i need to make any changes to the components value. and the resistor is it Or68 or zero R 68.
thank you
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This capacitors , you mentioned are nonpolarized , like MKP, MKT .....Wima
Resistors are 0.68 ohm / 2W (zero point sixty eight ) in parallel .
Alex.
Hi Alex,
Can I use two 0.33 1 watt resistor in series in place of 0.68 2 watt.
.... use only one resistor ,with value 0.33 ohm/ 4W or 5W se schematic
Alex.
My bad , i should have seen the schematic, thank you so much.
what will be the optimum power supply to utilize the amp to its full power in both 8 ohms and 4 ohms.
if I use 2sc2922-2sa1216 transistors instead of 2sc5200-2sa1943, what will be the difference in audio quality, will pcb component need any changes.
Can i use 2sk1530-2sj201 transistor with this amp.
thanks a lot.
Hello,
Finished assembling most of the amp pcb, except the transistors.
Please check before i finalize it.
My test psu is 37-0-37 3 amperes, is it fine. What test measures should i take for proper running of the amp.
How to set the bias for each transistor , I have never done before
I did not get 10uf bipolar 63v, so 50 v is mounted.
did not get e33 5w so e33 1w series mounted.
To both the Alex Sir's Please tell what would be the difference in sound quality if i used 2sc2922-2sa1216 in place of 2sc5200-2sa1943
Finished assembling most of the amp pcb, except the transistors.
Please check before i finalize it.
My test psu is 37-0-37 3 amperes, is it fine. What test measures should i take for proper running of the amp.
How to set the bias for each transistor , I have never done before
I did not get 10uf bipolar 63v, so 50 v is mounted.
did not get e33 5w so e33 1w series mounted.
To both the Alex Sir's Please tell what would be the difference in sound quality if i used 2sc2922-2sa1216 in place of 2sc5200-2sa1943
Attachments
Hi ,
Very nice board , but please change resistors to correct value 0.33 ohm /4-5W .
It's only one way to find how will affect by replacement , but pakage MT200 are a little to big for this . IMO not will affect the sound ..... You cannot set bias for each transistor , just for all tranies from one rail , positiv /negativ adjusting 1Kohm trim potentiometer (wich is missing from PCB )
Alex.
Very nice board , but please change resistors to correct value 0.33 ohm /4-5W .
It's only one way to find how will affect by replacement , but pakage MT200 are a little to big for this . IMO not will affect the sound .....
You cannot set bias for each transistor , just for all tranies from one rail , positiv /negativ adjusting 1Kohm trim potentiometer (wich is missing from PCB )Alex.
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Hi ,
Very nice board , but please change resistors to correct value 0.33 ohm /4-5W .
It's only one way to find how will affect by replacement , but pakage MT200 are a little to big for this . IMO not will affect the sound .....
Alex.
Hello,
Got the trim potentiometer mounted, 0.68 ohms 2w resistors mounted, Coil at speaker out.
Alex what is the purpose of coil at speaker out.
Should i keep 10r 1w which is connecting Input gnd and Psu gnd, or remove it.
Is it possible the output will distort at high volumes if not using protection board
Will mount transistors today after your review.
