Aleph 5 Monobloc Or Not

[george a]

Hi All

I am soon to commence (i hope)my Aleph 5's but am unsure as to which way to go with power supply.
i have the following bits

4 off 80000uF caps + 2 chokes
2 off Tranformers each 25-0-25 @ 50A

The dilemna, do I go single supply with total 160000uF per rail (320000Uf total) with either 1 transformer or 2 in parallel?

This would also involve use of chokes between caps( for a pi? filter??).

or

dual mon supply with i transformer per channel and 80000uF caps per rail for a total of 160000uf per amp. - no chokes though

Any comments welcome..
Thanks in advance

[george a]

Or I could do this to power subs as well (plus P1.7 Preamp)....

[george a]

actually -correct wiring of the diodes and caps would work ebven betterer! ....doh!

I'm sure you all get the idea..

[Taco]

The production Aleph's don't use a coil in the powersupply. So I would suggest to use 1 trafo+ 160.000 uF a channel. I would not recommend to power also your preamp from the same supply, The P1.7 needs a 60 Volts (dual 30V secundair for your trannies) I don't see how you want to get this wiht transformers with 25V secundair voltage.

[george a]

Taco
thanks for reply
if you at posted schematic you will see wher i'll get higher voltage from, which can then be regulated for the P1.7.

[Taco]

Now I see what you'r doing :P, this only works with 1 common supply but don't you get an uneven load on those trannies. Don't know of this matters.

[MikeW]

It depends on how you are going to cool them. If they are built in as stereo you will not be able to lift them unless there are fans. The stereo A-30 that I built with the R-theta heatsinks is 72 pounds. It has a 20 degrees rise. The mono blocks will be more work but easier to move.

[george a]

Taco

Transformers each rated at 2.5kva , preamp load probably.
not an issue
I beleive alpeh 5 draw constant current and hopeffuly wont react with supply to preamp.
Subs supply (feeding Hafler dh200 clone) may be a different story though. if this proves a problem then i have a spare Hafler to use as a stand alone bass amp.
Am just trying to get the poewr for the preamp from somewhere without having to by another transformer.
Also trying to keep things a bit more compact

[george a]

MikeW

I am thinking of fan cooling + 2 boxes -
one for Power supply and one for power amp.
Will probably still weigh in at about 70 pounds anyway....
Transformers currently power hafler clone and I can carry it short distances only.
I will probably also need some hefty cables for linking the 2 boxes- may put half of caps in amp box...(160000uF)

[Taco]

Originally posted by george a
MikeW

I am thinking of fan cooling + 2 boxes -
one for Power supply and one for power amp.
Will probably still weigh in at about 70 pounds anyway....
Transformers currently power hafler clone and I can carry it short distances only.
I will probably also need some hefty cables for linking the 2 boxes- may put half of caps in amp box...(160000uF)

It's a good idea to put some of the filtercaps in your ampcase. And now realizing that you use 2,5kVa trannies I think it's no problem at all using 1 supply for both.