Single Ended CFA

[bogdan_borko]

RB values for +45V power supply:
0.5A 47K
0.8A 51K
1A 56K
1.2A 68K
1.5A 75K

10W at 8 Ohms +45V/1.4A bias 1-NDR 2 DR (degeneration resistor)

 

[bogdan_borko]

Small signall +/-1V 20KHz, overshoot is from the crapy sqare generator, maybe adds a little bit..
No more measurements, I'm very happy about results and more important, it sounds great.

 

[analog_sa]

Fantastic results!

Did you get a chance to try 0.1ohm emitter resistors?

 

[Vunce]

Real nice work Borko!
Looking forward to assembling this amp. Even though it’s summertime and I really don’t want another heater in the house, I couldn’t resist.😀

 

[gary s]

Hi Vunce, that is OK for your Summer, but come Winter you will be looking for all the Class A amps you can find. Looking forward to your summary and thoughts once you get the amp built.

I might just get some pcb's made for a future project - looks promising indeed.

 

[bogdan_borko]

Fantastic results!

Did you get a chance to try 0.1ohm emitter resistors?

Yes, look at latest schematic. Sorry for messy thread I'll organize all the data in a few days.

 

[gary s]

That will be good if you can do that as it will make it much easier for prospective builders like me to gather all the relevant data in one post. I have prasi's gerbers to get the pcb's done. Final as tested schematics, pcb layouts and BOM will be perfect along with any other important details to build the amps will be much appreciated by the members here - thanks.

 

[bogdan_borko]

Ok I'll do that tomorrow.
Cheers.

 

[gary s]

No rush at all, get all the info together and members will be OK with that I am sure.

 

[bogdan_borko]

I think it will be in a form of short article with all data needed.

 

[Vunce]

Look what the Yellow and red truck delivered today. Simply amazing....5 days from placing the order to them arriving at my front door from halfway around the world!!! Now to order parts......

Sweet layout Prasi 😉

 

[r_jik45]

Nice clean work!
Not sure yet how the capacitor bank is used though.

 

[bogdan_borko]

Great Vunce, your 're fast!
Capacitor bank pcb is optional, instead of using onboard output cap.

 

[gary s]

Looks good Vunce, waiting for your impressions.

Thanks for all the time and effort you have put into this design Bogdan - very impressive.

 

[AKSA]

Me too, Vunce, I have high hopes for this design and really interested in your comparisons with your fine stable........

Hugh

 

[Vunce]

Hi Hugh!

Yes, the stable keeps growing. It’s an uncontrollable sickness! 😀
But, I guess if your going to have a vise, this is pretty safe and the family enjoys the fruit it bears.
I’m looking forward to this build also, the board is very compact. I definitely could go the CPU cooler/Noctua fan route, or keep it simple with a conventional AL heatsink.

Cheers,
Vunce

 

[gary s]

Have you thought about seeing a doctor Vunce.😉

 

[bogdan_borko]

Dr. Mouser or dr. Farnell? 😊

 

[AKSA]

Most doctors I know are very keen on audio.........
No help them. They would increase your meds.

Hugh

 

[r_jik45]

Capacitor bank pcb is optional, instead of using onboard output cap.

Mostly heard about input capacitor (or no input cap for direct input), so was asking about the output ones on the board 😱
At least it saves space for those not using this option.