100W Ultimate Fidelity Amplifier

These just came in the mail. Great layout by Prasi on AX11 Bimo mod.

Thanks Prasi!

This will be my first Apex BJT output amp.

563276d1470355326-100w-ultimate-fidelity-amplifier-image.jpeg

Yes, I also remember Mr. Mile saying next amp is always the best amp. Almost summarizes the thing we do here everyday- build new amps😀. all the best for your build. here is the stuffing guide that i had sent you long ago, in case you dont find it.
reg
Prasi
 

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Congratulation. 😎

Can you share the components that you changed?
How about sound impression?[/QUOTE

I slightly lowered the current through VAS transistors (R12, R16), using 68R instead of 47R.
R1 = 750R
C2 = 220pF
R22, R23 = 0R33

I am short of time at the moment so I shall share subjective impressions later.🙂

prasi, we are waiting for gerber, pdf 🙄
 

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I could be wrong but it seems to me that Q7 (MPSA18) is oriented in the wrong way on both Bimo's and Prasi's pcb. MPSA18 has ebc pinout. Either MPSA18 should be rotated or some other transistor with cbe pinout should be used.

I don't think so,prasi pcb is ok.

Emiter of MPSA18 goes to base of BD139 on the pcb, but in the schematic emiter of MPSA goes to base of BD140. Bimo's pcb has positive side of circuit on the right side while on most versions of AX11 pcb positive side is on the left.

PCB is OK if you use transistor with reverted pins like BC517 instead MPSA18.

Q7 orientation should be reversed by 180 deg if using MPSA18 (EBC) in the above PCB. or use BC517 (CBE) with orientation as per silk.
is the PCB correct, or not?
 
Thanks for confirming the PCB is WRONG !
Get it sorted before a stream of Builders start posting "my amp does not work" .
Remove the reference to MPSA18 and swap the E and C labels on the outer pins.

No need to type in capital letters. read forum rules!:nownow:.
 

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which rule states that capitals cannot be used to emphasis the point?
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