100W Ultimate Fidelity Amplifier

[a.wayne]

AX14 is 'Ultimate Fidelity Amp', FX14 and NX14 are MOSFET and QUASI (NMOS) variation with same VAS, all work great. In many threads people argue BJT vs MOSFET or vs QUASI, but with different VAS, speakers... I build and test AX14,FX14 and NX14 listen and compare sound on same speakers with same PSU, and I don't want share expiriance about that, it's your own to find.
Regards

Hello Apex,

How much "ultimate fidelity" is the ax14, what are you comparing it 2 , what is your reference ?

Regards,

 

[apexaudio]

Hello Apex,

How much "ultimate fidelity" is the ax14, what are you comparing it 2 , what is your reference ?

Regards,

Go to posts #48, #179, #216...
Regards

 

[mihailo]

Hi Apex i want to build your amplifier in post #135 send me PCB and dimensions please.
Regards

 

[mihailo]

Hi Maouna.
CAn you post me PSU pcb dimensions please.
Regards

 

[apexaudio]

Hi Apex i want to build your amplifier in post #135 send me PCB and dimensions please.
Regards

I try to find this pcb file, for protect go to thread:
http://www.diyaudio.com/forums/solid-state/162081-dc-servo-mosfet-amplifier-3.html
post #23,
Regards

 

[mihailo]

Thanks Apex.
Regards

 

[apexaudio]

Hi Apex i want to build your amplifier in post #135 send me PCB and dimensions please.
Regards

PCB from post #135 size: 47,5x82,5mm
Regards

 

[a.wayne]

Go to posts #48, #179, #216...
Regards

Hello Apex,

I did , that did not answer my question , you are claiming "ultimate fidelity "
i need a reference from you to get an clarification , ultimate fidelity compared to what ?

As good as Levinson ? better ? or just better than typical diy stuff ? can it drive an ESL?

regards,

 

[apexaudio]

Hello Apex,

I did , that did not answer my question , you are claiming "ultimate fidelity "
i need a reference from you to get an clarification , ultimate fidelity compared to what ?

As good as Levinson ? better ? or just better than typical diy stuff ? can it drive an ESL?

regards,

Better than typical brand about 100w, better than typical diy stuff, can be compared with any amp without embarrassment...
I can't give quick, short, easy answer, see thread:
http://www.diyaudio.com/forums/solid-state/165024-best-amplifier-world.html
Regards

 

[apexaudio]

Hi Apex i want to build your amplifier in post #135 send me PCB and dimensions please.
Regards

This also can help you to build 100W Hi-Fi amp,
Regards

 

[apexaudio]

2SC2240 for bias compensate was replaced with BD139 on this component layout.

 

[apexaudio]

Someone ask me for pcb of this amplifier. I test this amplifier with modern OP and Sanken darlingtons, and then I will share pcb design,
Regards

 

[apexaudio]

Hi Apex i want to build your amplifier in post #135 send me PCB and dimensions please.
Regards

If you have hum and noise problem put 10R resistor in input GND.

 

[apexaudio]

Fx14

2SK1529 and 2SJ200 can be use for FX14

 

[Rising Sun]

Hello apexaudio,

Can you please post the BOM for your Ultimate Fidelity amplifier?

What's the THD, slew rate and damping factor to expect?

Sounds good?

Thank you!🙂

 

[Rising Sun]

Can you please post the BOM for your Ultimate Fidelity amplifier?

I mean the IRFP240/9240 mosfet version - FX14. 😎

Do you have the pcb for it? I can´t find it in the thread...😕

Thanks!

 

[Rising Sun]

I'm building the AX14. After that I'll build the FX14 and compare the sound. 😎

I have some questions:

Does the BD139 be fixed to an output transistor for thermal compensation?

What's the bias I should use?

Thanks! 🙂

 

[Rising Sun]

my pcbs

This is the pcb I made for testing the AX14.

I allways have problems in getting the tonner to pass completely to the boards!
Well, this is what came out.

Regards,

Paulo.

 

[apexaudio]

This is the pcb I made for testing the AX14.

I allways have problems in getting the tonner to pass completely to the boards!
Well, this is what came out.

Regards,

Paulo.

You have mirror reverted pcb sides top and botom, you must put components on cooper side of pcb,
Regards

 

[apexaudio]

I'm building the AX14. After that I'll build the FX14 and compare the sound. 😎

I have some questions:

Does the BD139 be fixed to an output transistor for thermal compensation?

What's the bias I should use?

Thanks! 🙂

I use same pcb for AX14 and FX14, BD139 is fixed direct to heatsink, thermal compensation is "too good", on FX14 bias decrease from 200mA to 120mA when amp warm.
Regards