100W Ultimate Fidelity Amplifier

[joeyt]

hello sir apex, can i replace with this transistor the bd139, bc639,and bc640? this are the available parts in our place. i am going to build your ax11 for home listening music

bd139- mje340, bd135, bd137
bc639- 2sd667, 2sc2383
bc640- 2sb647, 2sa1013, bc327

thanks,joeyt

 

[joeyt]

got it sir apex, those are available here thank you very much for your quick reply.



thanks .joeyt

 

[shravanth]

Hello apex sir, do I need to add NFB for ax-14, or no need ?

 

[joeyt]

hello sir apex,
can i use a 10 amperes bridge rectifier diode for 1 channel? for ax11

thanks,joeyt

 

[apexaudio]

hello sir apex,
can i use a 10 amperes bridge rectifier diode for 1 channel? for ax11

thanks,joeyt

Yes, 10A is ok for stereo with +/-35V rail.

 

[shravanth]

hello apex sir i need add 0.1uf and 10 ohm 5watt resister in series at APEX AX-14 speaker terminal or no need

 

[apexaudio]

hello apex sir i need add 0.1uf and 10 ohm 5watt resister in series at APEX AX-14 speaker terminal or no need

Yes, zobel network must be add

 

[ridelperez34]

Sir Apex can i use irfp640 in nx-14? and if i can use, how much max voltage supply? Thanks

 

[apexaudio]

Sir Apex can i use irfp640 in nx-14? and if i can use, how much max voltage supply? Thanks

Use IRF540 with +/-40V maximum rail voltage.

 

[ridelperez34]

Sorry Mr mile its irf640, i have 8pcs of these and i want to use these in nx-14 if possible. thanks Mr. Mile.

 

[cjkpkg]

Woo Hoo...got my AX-11 TO-3 boards etched last night and my Mouser order will get delivered today.

Should be up and running tonight or this weekend sometime...

 

[clovi_kate]

Yes shematic in this point is wrong but pcb is o.k.
By the way this is shematic for AX11.

and what would be the effect if its connected?..i saw those other design emitter of driver transistors are connected in output stage..

 

[cjkpkg]

Nice Willy very nice. hey my man I'm putting together your version of AX-11 MKII and well if some one can help me out I will really appreciated, 😀 today I'm putting together must of the component I have on hand I just need to get me the transistor MPSA-92,BD679A,MJ15003/4,MJE15030/1, and resistors 4R7/1W and the emitter resistors 0.22/5W, so far is going well 🙂, here my question I do not have 331 caps, can I use 220pF or 180pF instead ?


Regards
Vargas

ok I am using Willy's TO-3 version PCB but for the use of 2n5551 I think the silkscreen file is wrong. The originally spec'd BC546 goes C(1)B(2)E(3) but all the datasheets for 2n5551 go E(1)B(2)C(3) when looking at the flat side as "front"

Has anyone built the AX-11 TO-3 version with 2n5551 at the front end and can verify this?

 

[AndrewT]

Yes, BC is reverse of 2N.

Just turn around if a swap BC to 2N or 2N to BC is required.

There are some specials, BC L for example.
It is always worth checking each new batch that you buy and writing on the package/envelope what pin layout they are.

 

[cjkpkg]

Thanks Andrew...always good to have a second set of eyes...

 

[kandimba]

AX14P

P { margin-bottom: 0.21cm; } Hi Dear mister Mile ! I have changed a little beat my initial plans, because I decided to give a gift to my nephew and I did your AX14P first, for him. I should say something for you, the world needs persons like you to go further, because you teach and share your knowledge. I changed a litlle beat your design about AX14 PCB, and I put the protection there, C7 33pF, C9 C10 22pF, Q1, Q2, Q3 2SA970.


For those wants to do de same amplifire here is, this PCB only needs a correct components on the correct place, nothing more nothing less... No PCB errors, no hummms, no noises, no nothing... the only thing is a very good sound, everything is OK, good and natural healthy bass, very clear and sweet midle and crystalline high. Next project, is AX20 for me.


Thanks Mister Mile

 

[apexaudio]

P { margin-bottom: 0.21cm; } Hi Dear mister Mile ! I have changed a little beat my initial plans, because I decided to give a gift to my nephew and I did your AX14P first, for him. I should say something for you, the world needs persons like you to go further, because you teach and share your knowledge. I changed a litlle beat your design about AX14 PCB, and I put the protection there, C7 33pF, C9 C10 22pF, Q1, Q2, Q3 2SA970.


For those wants to do de same amplifire here is, this PCB only needs a correct components on the correct place, nothing more nothing less... No PCB errors, no hummms, no noises, no nothing... the only thing is a very good sound, everything is OK, good and natural healthy bass, very clear and sweet midle and crystalline high. Next project, is AX20 for me.


Thanks Mister Mile

Nice work,
Regards

 

[MasPaimin]

Hi Mr. Mile..
can u upload Layout this shematic..

Pre-amp for ultimate fidelity.

very thank before..

sory, my grammar is bad

 

[cjkpkg]

ok I am using Willy's TO-3 version PCB but for the use of 2n5551 I think the silkscreen file is wrong. The originally spec'd BC546 goes C(1)B(2)E(3) but all the datasheets for 2n5551 go E(1)B(2)C(3) when looking at the flat side as "front"

Has anyone built the AX-11 TO-3 version with 2n5551 at the front end and can verify this?

OK,

Got my 2n5551's all straightened out and in the correct way.

Both channels just fired up and all is well!!!

V+/- = 34V
dropping 34mV across the 0.22R resistors = 154mA
3k3R across the bias network was obviously way to high
funny though...2K2 wouldnt bias up...I had to play with some parallel resistors across the 3k3 to get it to bias...ended up somewhere around 2K7 for the above values.

I thought I blew a fuse when I turned it on - it is that darn quiet.

Still need to get a couple more pieces of hardware and clean the wiring up a bit but for now its good to go!

Thanks for the circuit and PCB design guys!

 

[apexaudio]

OK,

Got my 2n5551's all straightened out and in the correct way.

Both channels just fired up and all is well!!!

V+/- = 34V
dropping 34mV across the 0.22R resistors = 154mA
3k3R across the bias network was obviously way to high
funny though...2K2 wouldnt bias up...I had to play with some parallel resistors across the 3k3 to get it to bias...ended up somewhere around 2K7 for the above values.

I thought I blew a fuse when I turned it on - it is that darn quiet.

Still need to get a couple more pieces of hardware and clean the wiring up a bit but for now its good to go!

Thanks for the circuit and PCB design guys!

Nice work, what about sound?
Regards