Aleph X transformer thread

[roddyama]

Brian,

In one of the previous AlephX threads you said that VM would do the quantity discount even if we wanted different output voltages. That VM was more concerned about the core size. If this is still true, the 600VA @ 2X40Vct (-20-0-+20) would be workable for stereo Aleph 3 or 30 and 500VA @ 54Vct (-27-0-+27) would work for one channel of an Aleph 5 or 60. This could bring in more orders toward the quantity discount.

What is the range of outputs that VM will accept for these orders?

Rodd Yamashita

[BrianGT]

Originally posted by roddyama
Brian,

In one of the previous AlephX threads you said that VM would do the quantity discount even if we wanted different output voltages. That VM was more concerned about the core size. If this is still true, the 600VA @ 2X40Vct (-20-0-+20) would be workable for stereo Aleph 3 or 30 and 500VA @ 54Vct (-27-0-+27) would work for one channel of an Aleph 5 or 60. This could bring in more orders toward the quantity discount.

What is the range of outputs that VM will accept for these orders?

Rodd Yamashita

I will talk to John about this tommorrow. For the 500VA, it is $68 for one and $62 for 10 or more. 600VA is a few dollars more, due to the extra wire.

I will ask him tommorrow about the different voltages, and power.

I picked up a 4x25 1kVA for my Aleph5 that I am planning on building (one Aleph2 chassis for the AlephX and the other for the Aleph5 )


One more thing, if we get a large order of the exact same specs for a transformer, we can get a 500VA custom one made by Plitron for about $52 each, but they all would have to be the same specs, and would have the canadian shipping charges.


--
Brian

[roddyama]

I pick up a surplus 1000VA @ 35-0-35 from Plitron a while back. If I recall correctly, shipping was a little more then $15USD to the Detroit area. Not bad, but it could offset the price difference.

Rodd Yamashita

[BrianGT]

Originally posted by roddyama
I pick up a surplus 1000VA @ 35-0-35 from Plitron a while back. If I recall correctly, shipping was a little more then $15USD to the Detroit area. Not bad, but it could offset the price difference.

Rodd Yamashita

Interesting. I just found their surplus page myself:
http://www.plitron.com/pages/surplus.htm

The 1.5kVA 4 x 18vac x 21A would be interesting to use if you want to make a stereo high powered aleph-x... I couldn't imagine the heatsinks, but if you went for active cooling, it would be possible.

Speaking of active cooling, are there any interesting solutions out there for high dissipation? I have a friend with a couple of intercoolers laying around from his turbo projects for his car....

--
Brian

[roddyama]

Originally posted by BrianGT


Interesting. I just found their surplus page myself:
http://www.plitron.com/pages/surplus.htm

The 1.5kVA 4 x 18vac x 21A would be interesting to use if you want to make a stereo high powered aleph-x... I couldn't imagine the heatsinks, but if you went for active cooling, it would be possible.

You could also do a separate central PSU enclosure with dual amp enclosures, then the heat sinks get a little smaller per enclosure.

Rodd Yamashita

[macka]

For forum members building the Aleph x in Australia Harbuch Electronics sell the 15+15 volt transformer @300 va for A$48.00 plus gst each, and they have them in stock at the moment.

macka

[wuffwaff]

just some food for thought,


I´ve calculated a few PSU´s with psudesigner to see what transformer I should order for my Aleph X. With those low voltages and high currents the Vdc = Vac x 1.2-1.4 rule doesn´t work that well anymore.

For a 16v supply with a pi filter and 10A of total bias I would need a 16V transformer.
With those currents every 10th of an Ohm gives a voltage drop of 1V!

So what I would like to point out is that one should be really carefull ordering 12V trafos and such. With a healthy bias this will give only 12V dc wich will give + and - 9V output i.e. only 20watts into 8 ohms.

william

[AudioFreak]

Yes, at 12 Vac the AC --> DC multiplier is down to 1.1 at best. Stick the inductor in there for the pi filter and 1:1 is looking quite realistic indeed.

[UrSv]

European warning!

Reichelt has 12, 15 and 18 V at 330, 500 and even 800 VA. Prices are cheap at EUR 39 for 500 VA and EUR 56 for 800 VA.

Elfa has 12/15(only up to 300 VA)/18 up to 500 VA.

http://www.reichelt.de/
http://www.elfa.se/

[wuffwaff]

forgot another thing:

those nice ultra fast recovery diodes have a forward voltage drop of 1.4-1.7 volts (HFA08TB60).

william