100W Ultimate Fidelity Amplifier

[ivanlukic]

Yes, use 22k for R10 and 10k for R6. No need to use cap accross R10. I prefer to use higher value of C7 and C8 to solve the problem of instability. In my AX11 builds I used 100pF for these two caps and have only very small overshoot on square waves. This circuit is AX11 without output transistors so I expect it to work even with 100pF. If you want to play safe use 220pF.

 

[bimo]

Should i change R10 from 10K to 22K as R2 for minimum output offset?Also could i use a 10p cap across R10 or from T6 collector to base of T3 to improve stability?

This is my simulation with slightly modification.

 

[sajti]

It can be even better to use another output devices, such as KSC3503/KSA1381...

Sajti

 

[bimo]

It can be even better to use another output devices, such as KSC3503/KSA1381...

Sajti

Agree.

 

[masood251]

In this 2pic.what is correct about the direction of zeners

 

[DevilDrums]

Your google translate question made no sense.

the Apex amplifier 33 ... I put together a second channel . Output voltage rise to 4.7 Volt. It doesn't heated. looks like an amplifier excitation.

 

[apexaudio]

In this 2pic.what is correct about the direction of zeners

Second picture is correct direction of zeners.

 

[Bangla H]

FH9 Zener orientation

masood, thank you for watching with eagle eye.
Don't know who it happens to that. I have saved correct File FH9 by Sonal.

Sorry for my bad view...arrrgh!!! .

 

[shabusf]

Hi Mr. Mile,
Thank you for correcting me. My impression was like P30ZF is the right choice for A40. Now I understand that I was wrong

Thank you
Sha

P30

 

[masood251]

Sonal Kunal - thanks! Looks fantastic.

https://www.diyaudio.com/forums/attachments/solid-state/560703d1468819884-100w-ultimate-fidelity-amplifier-fh11-
ver1.02.png

It's very convenient that pin outs for BD139/140, KSC3503/KSA1831, MJE340/350 are the same. Note that on VHEX+ amp, vzaichenko drives a pair of IRFP's with a single KSC/KSA just fine so it may still be suitable to use those drivers. I believe they may have slightly better noise/performance figures over the MJE's.

I have both so it's not an issue - just wondering which will give best performance.

Dear kunal in fh9 how maximum dc voltage.i have 35..0..35 vac trafo .can i use it in fh9 ampl.thanks

 

[kandimba]

Dear kunal in fh9 how maximum dc voltage.i have 35..0..35 vac trafo .can i use it in fh9 ampl.thanks

Hi, yes you can, 35-0-35 VAC it means 48-0-48 VDC

 

[masood251]

Thanks dear

 

[masood251]

Sir i want to speaker connection in above said ampl.i connect spek.out and ground but not sound.plz help me thanks

 

[kandimba]

Sir i want to speaker connection in above said ampl.i connect spek.out and ground but not sound.plz help me thanks

You should chek the electronic components. Can you post fotos.

 

[svinx]

Please share the file for order on the PCB way gerber

 

[kandimba]

If you want this, AX14P.

 

[svinx]

Thanks for answering! Need to gerber file ax14 and ax11, ax14p does not fit

 

[rehman]

hellow everyone. i need a digital source selector for amplifier with default output or previous source output the amplifier was turned off but i dont find the suitable schematic . i need help.

 

[eliasib]

It is a scheme well known from Apex.. but I see Vbe multiplier transistor was replaced by a pair of diodes. I don't like that idea but it can work.

 

[aliskamjad]

Want to build a Stereo Amplifier with Apex AX-14P + TB1 + TB3 + Apex 2x24V PSU.
Can someone help me with TB1 & TB3 toner transfer pdf.
Do I need PSU 5 for for AX-14?
Is this transformer (40Vac-0-40Vac @6 Amp) ok for Apex AX-14 Stereo Amplifier, please suggest.