Newbe, witch Aleph should i build..?

[Magne]

I'm new to audio build, so i need some advice..
I want to build an Aleph BOSOZ and an Aleph amplifier, but i need some more info.
I have been searching a lot in the forum but not found answers for all my questions.

What is the difference (soundwise) between the Aleph 2/4/5/X?
Can I use a 42v 800VA transformator for Aleph 4/2? it is designed for 40v/37v, is the voltage critical?

I want an amplifier who has power and very good sound (as most of you ) from 20 - 20kHz. witch Aleph has the best compromise?

[kilowattski]

The 42 volt 800 VA is usable but you would need four of them for Aleph 2/4 monoblocks. The best solution would be to get two 800VA to 1000VA toroidal transformers each with dual 37 volt to 42 volt secondaries. You need one transformer for each monoblock. The biggest expense will be heatsinks large enough (rated at least 0.11K/W per monoblock) to dissapate the heat generated by the gain and css transistors.

I wish I could tell you which one sounded best but sound is in the ears of the beholder and is very subjective. I can tell you that they all sound good to me, but that is my ears.

[steenoe]

No chance you can use those trafo's for an X. Too high voltage. The easy way around it, would be to join the Mini aleph GP, and build yourself an Aleph 5. Like I intend to, whenever I get the time Seems like all my old pal's need's new equipment!!
Check this site: http://www.diyamps.com/aleph/
The BosoZ is a nice companion for that amp. This approach would demand some new trafo's though I never based a project on stuff I had already. If it is worth building for you, it will pay to get a pair of suitable trafos Just my thoughts

Steen

[kilowattski]

Originally posted by Magne
Can I use a 42v 800VA transformator for Aleph 4/2? it is designed for 40v/37v, is the voltage critical?

I thought he was just asking about the Aleph 2 and Aleph 4. Anyway, he really can't use the transformer on any of the amps he mentioned except the Aleph 2 or Aleph 4.

[steenoe]

Guy, he asked a lot of questions:

What is the difference (soundwise) between the Aleph 2/4/5/X?

Well, he did mention the X, in there I just said as I did, to keep him from going for the X, with those trafo's Soundwise, I do not have a clue What I have heard so far from Pass, is top class. All of them This goes all the way back to the A8000 From the late 70's Stasis, Aleph, whatever They all sounds great to me

Steen.

BTW No attempt to dismiss any of your sayings, whatsoever You are quite serious as allways, Guy

[kilowattski]

Steenoe,

Just keeping you on your toes on a rainy afternoon in New York......But as usual you are as sharp as a tack....

[steenoe]

Just keeping you on your toes on a rainy afternoon in New York......But as usual you are as sharp as a tack....

Thanks a lot, Kilowattski Rainy?? I was under the impression that we globally had a tropical summer Just listen to JH Maybe the rain is the Monsoon, moving up to the middle states Nonetheless, we are enjoying the best beach weather for years, here in Denmark

Steen (cool, but somewhat overheated anyways )

[Magne]

Originally posted by kilowattski
The 42 volt 800 VA is usable but you would need four of them for Aleph 2/4 monoblocks. The best solution would be to get two 800VA to 1000VA toroidal transformers each with dual 37 volt to 42 volt secondaries. You need one transformer for each monoblock. The biggest expense will be heatsinks large enough (rated at least 0.11K/W per monoblock) to dissapate the heat generated by the gain and css transistors.

I wish I could tell you which one sounded best but sound is in the ears of the beholder and is very subjective. I can tell you that they all sound good to me, but that is my ears.

Oh God! Four of them.. that will be a too large construction, they would be HUGE..

You say the heatsinks need to be at lest 0.11K/W, what do the K stand for? I have some rated [0.3C/W at 300W] (300mmX100mm with 83mm fins) they will be about 60deg. Celsius at 200w, so by using 2 for each monoblock that would be 60deg@400w
is this usable for any of the Aleph's? std X maybe?
with a 18v 600VA trafo.

By sound i was thinking mostly about some saying that one Aleph has good bass but not so detailed mid-treble, and another Aleph had exelent detail etc. but do not have that powerful bass, if you know what i mean..?

Originally posted by steenoe
Guy, he asked a lot of questions:
Well, he did mention the X, in there I just said as I did, to keep him from going for the X, with those trafo's Soundwise, I do not have a clue What I have heard so far from Pass, is top class. All of them This goes all the way back to the A8000 From the late 70's Stasis, Aleph, whatever They all sounds great to me

I only thougt about the 2and4 with the 42v trafo.

Thank you all for your replys!

[wuffwaff]

Hi,

K stands for Kelvin and can be substituted by °C in this case.

200 watts and 0,3°C/W means 63°C ABOVE ambient so around 80-90°C wich is a bit too much

Before you build an Aleph first look at your speakers impedance and see if you need more power at high or low impedances.

William

[kilowattski]

I don't know about your heat sink calculations. If you use two of them, each sharing the 260 watts of dissapation per monoblock for an Aleph 2, using 0.3 c/w at 130 watts of dissapation the heatsink will be at 20+(130 x 0.3)=59 degrees c per heat sink. I think you forgot to add the 20 degrees c ambient temperature. Don't forget they are rated in rise above ambient. I agree with William that at 60 c you need much more heatsink. I recommend the Siefert KL-271 rated at .18 c/w which would put you at 47 degrees c. They are about $70 USD/sink x 4=$280 USD to do both monoblocks.