Newbe, witch Aleph should i build..?

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Magne

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Joined 2005
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

kilowattski

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Joined 2003
woodworkersweb.com
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

steenoe

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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:xeye: 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:xeye: 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:cool:
 
steenoe

steenoe

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Joined 2004
Guy, he asked a lot of questions:
What is the difference (soundwise) between the Aleph 2/4/5/X?
Click to expand...
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:D This goes all the way back to the A8000:) From the late 70's;) Stasis, Aleph, whatever;) They all sounds great to me:)

Steen.:cool:

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

steenoe

Member
Joined 2004
Just keeping you on your toes on a rainy afternoon in New York......But as usual you are as sharp as a tack....
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Thanks a lot, Kilowattski:D Rainy?? I was under the impression that we globally had a tropical summer:D Just listen to JH;) Maybe the rain is the Monsoon, moving up to the middle states:D :D Nonetheless, we are enjoying the best beach weather for years, here in Denmark:) :)

Steen:cool: (cool, but somewhat overheated anyways:D )
 
M

Magne

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Joined 2005
Re: Re: Newbe, witch Aleph should i build..?

kilowattski said:
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.
Click to expand...

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..?


steenoe said:
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:D This goes all the way back to the A8000:) From the late 70's;) Stasis, Aleph, whatever;) They all sounds great to me:)
Click to expand...

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

Thank you all for your replys!
 
wuffwaff

wuffwaff

Member
Joined 2001
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:hot: :hot: :hot:

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

kilowattski

Member
Joined 2003
woodworkersweb.com
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.
 
M

Magne

Member
Joined 2005
yeah, that would be nice. about 50°C then, but the amps will be a bit big too.
Need them to be a bit "wife friendly" :D

From what I have been reading so far i guess my setup will be something like this:

22v rail
5-6A bias (so 22x6/2=66w out and 132x2=264w tot correct?)
600VA 18v trafo
200x300x83mm heatsinks

what do you think?
sounds nice to me :) 50°C fins and enough power (i think).
Will most likely be used in a 20-25square meter room with some 2x6,5" SEAS magnesium elements in each speaker.
 
kilowattski

kilowattski

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Joined 2003
woodworkersweb.com
If that is what you are aiming for build an Aleph 5 which is 60 watts per channel. Your sinks may still not be enough even for an Aleph 5. You want to keep those Gain and CSS transistors as cool as possible for long life and don't forget they must be matched. I think that 0.3 c/w would be good for an Aleph 3 or Aleph 30. You can buy PC boards for either Aleph 5 or Aleph 30 at http://web.vip.hr/pcb-design.vip. Kristijan also has the power supply schematics for each one on the site. If you really need to keep it small maybe a Class AB design or Mini Aleph is what you are looking for. The Aleph's are not terribly efficient amplifiers but they sound oh so sweet.
 
M

Magne

Member
Joined 2005
kilowattski said:
If that is what you are aiming for build an Aleph 5 which is 60 watts per channel. Your sinks may still not be enough even for an Aleph 5. You want to keep those Gain and CSS transistors as cool as possible for long life and don't forget they must be matched. I think that 0.3 c/w would be good for an Aleph 3 or Aleph 30. You can buy PC boards for either Aleph 5 or Aleph 30 http://web.vip.hr/pcb-design.vip].
Click to expand...

I was thinking of the Aleph-X because it is balanced, so i can get full use of the BOSOZ. AND the caps will be MUCH cheaper because the do not have to be "hi" voltage..
I don't need to use the 100mm heatsinks, i have noe problem bying new 200mm heigth ones. It just dont look so brutal with 100mm :)

so i think i will go for X with 200mm heatsink (aiming for 50deg.)
unless the 5 of some reason is a better choice..?

I have been looking at Kristijan's site and thinking of bying pcb's from him. looks good
 
kilowattski

kilowattski

Member
Joined 2003
woodworkersweb.com
That is fine. I really don't hear much of a difference between the Aleph X that I built and the Aleph 5 I built. I don't want to scare you away from an Aleph X but the Aleph X is a difficult project for a newbie. There is alot of tweaking involved with the Aleph X and you will need some test equipment to do it (o'scope etc.). Read the following thread: http://www.diyaudio.com/forums/showthread.php?s=&threadid=49528. William (wuffwaff) is an experienced builder with 20 years of DIY under his belt and he has done alot of testing and tweaking to get the amp just right. The regular Alephs can simply be built exactly to print without all the tweaking. The regular Alephs are a much simpler build for a newbie.
 
M

Magne

Member
Joined 2005
kilowattski said:
Have a look at Siefert KL-271 heatsinks @ 0.18 c/w.
Click to expand...

Where can I get the Siefert heatsinks?

kilowattski said:
I don't want to scare you away from an Aleph X but the Aleph X is a difficult project for a newbie.
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Ok, so I should go for an Aleph5 then, and maybe try an Aleph-X later.
Need to think about this for a few days.. :)
I have some electronic skills (2yr electronics school), so I'm not afraid of getting lost in an Aleph-X but it would be nice to make something that works without problems. :D
 
M

Magne

Member
Joined 2005
I will go for a BOSOZ and 2 Aleph-5!
and when I feel like making an X, I can use the X's for front speakers and the 5's for rear in my home-cinema project :D
something tells me I'm never going to need heating in that room :rolleyes:

I will post pictures as this project moves om, but i guess it will be a long term project :)
 
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