Which power-amp for ATCs

[busoni]

Hello everyone,

I' m reading this excellent forum some months now and I feel that time has come to build my first amp. Since I have no experience in amp building, I need your help making the right choice. The requirements would be something like this

- capable of driving 84-86dB speakers(possibly a pair of ATC SCM-11s or SCM-19s )
- pairing with NAD 320BEE's preamp stage at first. Poweramp stage has 20k input resistance
- being as easy as it gets
- being a Pass Labs design(...obviously the reason I opened the thread here)

Waiting for your replies

[MEGA-amp]

Whats your budget?

[Blues]

Our friend Babowana is building an F5 and he has an SCM7, you might want to hold-off and wait for his results...here's the link:
ATC SCM7 . . . with Papa's diy amp?

[busoni]

Blues, thanks for the link. I have already checked it. I just don't know if something
like 2x15W(e.g. Zen V9) would be enough for the ATCs, level-wise: it's only 93dBs at 2m,

Mega Amp, I don't want to spend more than 300 Euros(that's about $430).

[MEGA-amp]

I'd recommend an Aleph 5, 60W into 8R. Your budget is reasonable; costly items in order: heatsinks, big transformer (600VA min), power supply capacitors; for these items, the surplus market would be a good start to stay within budget.

Take a look HERE>>Misc Gallery>>Misc Amplifiers


-john

[busoni]

Thanks Mega-Amp. Is there any Aleph 5 build thread? Just to take an idea of how difficult the construction is... My search for one didn't turn out with something.

Also, any other ideas for a simple Pass Labs poweramp, even at lower wattage, would be heartily welcome!

[MEGA-amp]

Here's a good Aleph 5 build:

http://www.penguinlovers.net/audio/aleph5_proj.html

The biggest obstacle with any of these class A designs is building the chassis. If you build it very big, you can start out at lower wattages and go up from there. Build that first, as its usually the most time consuming. F5 might be a good start as well, although with your speakers, it may not be a good match, depends on your listening taste.

-john

[busoni]

Finally decided to build the Aleph 5 and have already started collecting
the parts. So some questions arise:
1. Are BHC slit foil electrolytics a good choice for power supply caps?
2. Nelson Pass' schematic suggests 4x25,000uF per channel. Would 10x10,000uF be a problem? I think that it's better since total ESR gets lower.

Also, where could I find Aleph 5 PCBs?

[busoni]

No answer?

[karajak]

hi i have two aleph 5 pcb s spare .its the mark finnis version.post me your e mail so i can conduct you .regards from athens! JOHN