Help Needed on the Aleph 1.2 Mechanical Layout

[jewilson]

I need help to locate a picture of the inside layout of the Aleph 1.2 or even the 2 amps. I'm a little confused that the power MOSFET's are located on all four sides of the amp. Therefore, I very interested to know what are the wiring and layout pits falls before I began my project.

This method obviously is different that other amps where the transistors or located on the right and left side. Maybe some one
can help me with my out with my confusion and a Picture. I have purchased surplus Passlabs heart sinks, so I want them to be close to the original mechanical layout.

Thanks
Jim

[jewilson]

Dear Mr. Pass,

Perhaps you have a JPEG image of the in side of your Aleph 1.2
you could share with us. We are using some surplus heat sinks
of your and would like to follow you original internal layout and
mechanical implementation.

Thanks for your Help

Thanks
Jw

[Peter Daniel]

Here's pic of Aleph 3: Aleph3

[Peter Daniel]

And here are some noce pics of Aleph 0. Those are not exactly what you are looking for, nevetherless can be a good source of inspiration
Naked pictures of Pass

[jewilson]

Originally posted by Peter Daniel
And here are some noce pics of Aleph 0. Those are not exactly what you are looking for, nevetherless can be a good source of inspiration
Naked pictures of Pass

Thanks Peter,

Does the Aleph 1.2 have the transformer located underneath the amp in it's only box. One of my concerns is the wiring distribution mess this could create. After closer examination, it looks like Nelson has a mother board which carries power and signals and hold the input circuitry. This seems to be the way to go if replicating the amp internal design. However, it seems like the square amplifier with transistor on all sides is more of a hindrance to the layout. Of course, the stray capacitance to outputs would seem to increase with this implementation. Any help is greatly appreciated.

Thanks
Jim

[Peter Daniel]

It all depends on available heatsinks. If they are big enough, using heatsinks on both sides only is much easier, considering layout and construction, although may not be as much appealing visually You might try Pass Gallery as well for some ideas.

Personally, I like Aleph 0 chassiss very much and consider it a classic. The later Alephs show more of a convenience reasons applied to construction. Of course the later designes provided more heatsink area

[jewilson]

We are using the same heat sinks that Nelson Pass used. A friend found these in a surplus metal shop in Calf. However, I did not know their was a bottom section for the transformer and extra hardware till you listed the link. So are the larger (1.2 and 2] amps built with the same concept, the transformer located underneath the main chassis? That would make sense. I like the way you laid out your amp out it make a lot of sense. Also, as you noted there are some very good ideas on the site, but I'm locked in to the original design concept because 3 of us are building them.

Now I'm wondering if I will need to layout board for power and signal distribution to make the layout clean. Maybe
I can unwrap some flat inductors to carry the power and out put of the main input board to make it simple.

Thanks
Jim

[LBHajdu]

Here you go :

[jewilson]

Thanks LBHajdu,

Peter Daniel has already sent me a link to this. Looks like the Aleph 1.2 is just and over grown Aleph 0 amp.

Peter, I know you've have built a version of the Aleph 2 using a more conventional layout method. Do you see any problems using the MOSFET on all side of the amp be side the length of signal runs. The Aleph sure is a different approach, it's also interesting that Nelson newer amps have gone back to the traditional layout method.

Maybe, not sure, it would be worth the effort to layout a PCB for the power supply, and signal and power runs, any ideas?

Regards
JW