100W Ultimate Fidelity Amplifier

[alex mm]

Let me present my new headphone amplifier based on SR PP12 schematic , not tested yet ,but tomorow will be ......🙂
Regards,Alex

 

[AKSA]

What beautiful work....... elegant, compact, exquisitely laid out.

Bloody genius, Alex, congratulations!

Hugh

 

[vargasmongo3435]

amazing ! Alex

 

[thole]

Ask For schematic

VAS from AX-14 can work with +/-120V DC rail voltage without change, with output stage upgrade U can get 500W/8R. I also use MOSFETs for some versions...
I made this class H version ' Ultimate 500' for test, and work great with +/-120V,+/-60V,0V rail votages.
Regards

Mr. Mile, can you share this Amp Schematic. AX14 with Stepper. It's very interested. Simple component & high voltage...!!


Regards

 

[alex mm]

What beautiful work....... elegant, compact, exquisitely laid out.

Bloody genius, Alex, congratulations!

Hugh

Thank you ,to kind 🙂

 

[alex mm]

amazing ! Alex

Thank you 🙂

 

[olafk]

Let me present my new headphone amplifier based on SR PP12 schematic , not tested yet ,but tomorow will be ......🙂
Regards,Alex

Looks great. Very cool !!! 😎

regards Olaf

 

[rombe570]

Apex AX14,chanel 2 almost ready, missing a few parts i'll buy them tomorrow.
What type of transistors can be used instead of 2sc5200/2sa1943.

Alex, nice work congratulations.

An externally hosted image should be here but it was not working when we last tested it.

how to do a screen shot

[img=http://s21.postimg.org/84rw3qgnb/20150329_181446_1.jpg]
image sharing

 

[thimios]

Let me present my new headphone amplifier based on SR PP12 schematic , not tested yet ,but tomorow will be ......🙂
Regards,Alex

My hat out!
Waiting for pcb 🙂🙂

 

[mihailo]

Apex AX14,chanel 2 almost ready, missing a few parts i'll buy them tomorrow.
What type of transistors can be used instead of 2sc5200/2sa1943.

[img=http://s21.postimg.org/84rw3qgnb/20150329_181446_1.jpg]
image sharing

Good substitutes are: 2SC3858/2SA1494, 2SD1047/2SB817, 2SC3263/2SA1294, 2SC3519/2SA1386, 2SC3855/2SA1491...
All 2SC/2SA, 2SB/2SD are good.
I even used a BD249C/250C with a little lower voltage, +/-45V MAX.

 

[still4given]

Apex AX14,chanel 2 almost ready, missing a few parts i'll buy them tomorrow.
What type of transistors can be used instead of 2sc5200/2sa1943.

I used MJL4281/4302. MJL3281/1302 will work well too.

 

[apexaudio]

Let me present my new headphone amplifier based on SR PP12 schematic , not tested yet ,but tomorow will be ......🙂
Regards,Alex

Nice work, is it tested?
Regards

 

[rombe570]

Today I finished the second chanel, and it doesn't work, i have 28vcc, and i can't set the bias. The first chanel has the same problem. Can someone help me please, i already change all transistors.

 

[apexaudio]

Today I finished the second chanel, and it doesn't work, i have 28vcc, and i can't set the bias. The first chanel has the same problem. Can someone help me please, i already change all transistors.

Conect input gnd to psu gnd...

 

[rombe570]

i already did it, but I still can't set the bias

 

[still4given]

Apex AX14,chanel 2 almost ready, missing a few parts i'll buy them tomorrow.
What type of transistors can be used instead of 2sc5200/2sa1943.

Alex, nice work congratulations.

An externally hosted image should be here but it was not working when we last tested it.

how to do a screen shot

[img=http://s21.postimg.org/84rw3qgnb/20150329_181446_1.jpg]
image sharing

I can't help noticing that your silk screen says BC547 and you have a BC546 there. Which one is wrong?

 

[apexaudio]

i already did it, but I still can't set the bias

Can you post some voltage measurements?

 

[AndrewT]

I can't help noticing that your silk screen says BC547 and you have a BC546 there. Which one is wrong?

does not affect amp operation.
The BC5xx range are graded for different duties.
546 is the higher Vce version.
547 is the medium Vce
548 is the basic.
549 is the low noise version.
560 is the low noise and medium Vce version.
Add 10 for the PNP versions, 556, 559, 560

But they are all much the same.

 

[still4given]

My mistake

 

[rombe570]

I test al transistors, they all seem ok, the amp worked for a few minutes then it died, i'll post some measurements tonight.