100W Ultimate Fidelity Amplifier

[mihailo]

Thanks Apex.

[apexaudio]

AX14 and D14

[sudhir kumar]

Originally Posted by remle114

This is my 1st post here
I woud like to say thank you to sir Mile for sharing those amplifier design
I build your AX- 14 TEF with 7 pair output and +/- 75V rail and compare to my existing
Crown XLS clone same power supply same output board bias set at 50ma.
For me AX-14 TEF is the clear winner

Would you please share your ax-14 TEF project along with pcb layouts??
Thanks in advance.

[Kei]

Been looking at building a power amp, quite interested in the AX-20 design. Made up a pcb drawing for sanken 2sa1295/2sc3264 from Qq12e5k1's original. Not sure if it's correct yet though. (not had time to double check it) This is by far the worlds neatest pcb but as its my first time doing this it wasn't necessarily going to look beautiful.


Labels on the Q12/14/19/20 are still 2sa1943/2sc5200. Q20 label is missing)

[apexaudio]

Kei
I suggest to add DC protect circuit with NE555 and overload detect like in AX16, there is lot of space on your pcb.
Regards

[keantoken]

I'm wondering, are the MT-200 cases really so good that it isn't better just to use two TO-3P devices for both screws?

[apexaudio]

Originally Posted by keantoken

I'm wondering, are the MT-200 cases really so good that it isn't better just to use two TO-3P devices for both screws?

I use SanKen 2SA1295/2SC3264 and replace with SanKen 2SA1294/2SC3263.

[keantoken]

Would there be any gain at listening volumes from using the 2SA1186/2SC2837 in the same way, for greater speed (<20MHz@100mA) and lower Capacitance (750pF/340pF)?

Also is there a good place I can get legitimate Sankens in America? Ten Four LTD seems legitimate, but I cannot buy small quantities.

- keantoken

[Kei]

The original design of the pcb seems to include some protection circuitry but it doesn't match the original schematic.




Would the PSU-7 design with the integrated protection circuitry work with this or will i need to adapt the amp pcb to make it work?

Originally Posted by apexaudio

Simple Soft-start, DC, Thermal and Overload Protect with NE555. Use single 12vac for suply.

Was this the NE555 protection you referred to? Presumably i'd use this instead of the triac/zobel based speaker protection terminals found earlier in this thread.

[Kei]

Would 2SA1859A & 2SC4883A be suitable alternatives for the toshiba 2SA1837 & 2SC4793 parts. (can't seem to find them at any of the usual UK suppliers) Have seen a post somewhere on here that said MJE15034G/15035G were suitable. (RS have them in stock but no brand is listed, datasheet is ONsemi)