100W Ultimate Fidelity Amplifier

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hi.

i check voltages from 5200 to c4793, mje350, bc547
and from 1943 to a1837, mje340, bc557

bc547 Vbe: 32V
bc557 Vbe: 557mV !!!!??????

i think bc557 gone i am not sure but i cannot test it cause i dont have that transistor right now.

can i use 2n551 and 5401 For bc547 and bc557 ?

Here is the PDF Still4given posted with voltages (based on +/-32vDC thought, so factor accordingly). Very helpful.
 

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Come on guys...no one to comment on sound quality of the AX14?? ...i am sure many of you have built it..so please come forward and share your experience.

OK, some brief words re SQ in my system, bearing in mind this is an active 3-way with the AX14 powering the mid-range panel from 450hz to 4500hz.

I find the amp very neutral, adding nothing I can perceive to the sound. Great dynamics, detail and imaging. Very happy with its performance in my system with no thought to returning to the previous mid-range amp which is also a strong performer. Also very well behaved with no turn on or off thump.

Cheers
 
Well, this morning while I was waiting for answers I went ahead and etched the dobrivoje layout. I wanted to try it with different transistors and I had a pile of BC456C/556C transistors so I populated this one with those. I haven't tested yet but here are some pics.

Blessings, Terry

hello, does it have something or affects the polarity of the capacitors at the input and output
 
OK, some brief words re SQ in my system, bearing in mind this is an active 3-way with the AX14 powering the mid-range panel from 450hz to 4500hz.

I find the amp very neutral, adding nothing I can perceive to the sound. Great dynamics, detail and imaging. Very happy with its performance in my system with no thought to returning to the previous mid-range amp which is also a strong performer. Also very well behaved with no turn on or off thump.

Cheers

Thanks a lot for your response
 
I collected and listened to the so-called APEX AX-20,
about which I want to share here. In fact, this is a classic amplifier
with all the improvements from Douglas Self’s textbook (and recommendations from local colleagues).
Compared to Apex AX-14, this amplifier sounds much more adult:
More dynamic sound, excellent control of 4 pieces 8 "bass. Bass is excellent.
Clear low. In the 14th, in comparison, a little tightened, just a little because of what
it seems that it’s even a little more.
who whant to do (gerbers) Apex_AX_20
 
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This is protect from my PA amps, can be used for Hi-Fi amps also.

hi i want to use this protect on ax14. but ax14 dont have protection out.
so i try to take it from b500 schematic but i am not good on it and need to some one check it please

the resistor values and capasitor is right? and if i make mistake pls tell me where. thank you
 

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  • APEX H900 Protect Component layout  apexden.jpg
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  • APEX PA PROTECT (1).jpg
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