Aleph 2 Board Design

[JayV]

I'm planning to build a pair of Water cooled Aleph 2. And is currently drawing the output board, and i would like some comments on the design... Will it work??

Perhaps i should give som explanation:

The blue block is the water cooling aluminium profile: http://www.elfa.se/pdf/75/07563109.pdf

(not all connections listed, it's just to get the point)
A connects to R20
B to C7
C to Q5
D to Q4
E to Q4
F to R7

With that kind of cooling.. how much power could i get out of the Aleph?

[Mark A. Gulbrandsen]

Now thats going to be one compact Aleph 2! I like the idea of water cooling but why not go one step further and include the drive components on that pcb also.......there seems to be plenty of room in the center area? It certainly seems like a logical thing to do at this point. Also, what kind of cooling system are you going to use? I'd be tempted to use a water chiller like the kind we use in large format film projection, although a bit smaller. They are not killer in price either, and can be had used for around 400 to 600.00. I'd locate the chiller in another room or the basement. Safety circuit built in so that if water flow stops the amp shuts down.......
Mark

[JayV]

Perhaps i should put the drive components on the other side of the board! Why not use the temperature switch from the original design? It should work fine connected to the water block.

My plan is to use a radiator from a car or something like that, wery cheap! and i'm thinking about running 8 alephs on the same system later (if the first pair is a success). It probobly would be a good idea to put the ratiator in another place, 2400W of heat should warm up the garage just fine

[Mark A. Gulbrandsen]

Here is one of the coolers(circulator) that we make in our shop for film projectors that require it. 10 gallon tank, 8 gallons of distilled water and one gallon of antifeeze to keep algae form growing and inprove heat transfer. Its simple and inexpensive to make. Should keep a dozen or more Aleph 2's at what ever temperature the room is at that the tank is kept in. We are removing lots of heat from projector aperatures with up to 10kw xenon lamps on them that would other wise buckle from the heat..... The aperatures run only slightly warmer than room temp! The cooling fan is really the only noise generated by the circulator...the water pump is for all practical purposes noisless. The radiator is a heater core for a car......

Indeed, the component parts can certainly be on the other side of the pcb!! Those Alephs would be tiny by comparison to others built here.
Mark

[moe29]

it's amazing how much heat you can dissapate from a heat sink
with just fans. I can imagine that this water cooling would work
really well. In fact you could probably go as far to say that the
only way you could have 6 or more channels of Aleph 2 work in
a home theatre situation would be to water cool it!

I remember reading something Mr. Pass said about air cooling his
home theatre alephs... he had pruchased a whole bunch of
computer cpu fans to implement somehow. wonder how that
worked out? : )

too bad Grey never posted pics of his water cooled Aleph 2.

it's a really cool idea, good luck, and post pics!


moe29
-----------------------------------------
Hail to the Thief is a masterpiece

[Mark A. Gulbrandsen]

I thought Grey did post some pics....at least there were some pics posted of someones water cooled Aleph something or other. What I saw was all home made and not how I would do it...nothing wrong with nomemade and I suppose it all works but this design is very elegant and simple...at least once all the primary components are mounted on the same board. If he gets it that far it'll be difficult to keep me from building 6 channels of Aleph 2's and the heat will be elsewhere!
Mark

[JayV]

I just switched from eagle to protel dxp (30 day trial), it seems to be a nice program! So i hope to have the design done in a few days for further comments

[bigparsnip]

you can get good cooling uisng just air if you have afan strapped onto the heatsink as well, al lot of CPU heatsinks are getting down to 0.2C/W or better using fans these days, so you could just about get enough cooling for seven chaneels into a normal ish sized case, but I bet there woud be a fair bit of niose comming from the fans when it was running. that is one ver good thing about water cooling, you can allways put the radiator and fans elsewhere and get rid of the niose that way, whilst still getting the benifit of the extra cooling from the fans.

[JayV]

I played around in eagle some, and tried to free some space for the drive components, and this should be enough! I belive its possible to route it all on one layer!

[JayV]

i just realized i forgot some routes between R34-R39.. but you get the point Anyway to increase the bias, is it only R19 to change or have i gotten this wrong?