Aleph 60 instead of Aleph 2(newbie)

[mats73]

Hi all!
I recently purchased Aleph boards from "harvardian" and set out to build a pair of Aleph 2s.
My partsourcing has been a little so-so however.
But.
I could quite easily acquire all the parts needed for the Aleph 60s instead and wonder if it would be a possible to build these instead, but still use the same boards.
I have, of course, looked at the schematics for both models and there are a few things that are different.....and since I am a newbie it doesn´t take a lot to confuse me......

Has anyone else tried to build the 60s from these boards, and maybe done a parts list that I could look at?

I also wonder what voltage rating that is needed for the 220uF caps?

[UrSv]

Originally posted by mats73
Hi all!
I recently purchased Aleph boards from "harvardian" and set out to build a pair of Aleph 2s.
My partsourcing has been a little so-so however.
But.
I could quite easily acquire all the parts needed for the Aleph 60s instead and wonder if it would be a possible to build these instead, but still use the same boards.
I have, of course, looked at the schematics for both models and there are a few things that are different.....and since I am a newbie it doesn´t take a lot to confuse me......

Has anyone else tried to build the 60s from these boards, and maybe done a parts list that I could look at?

I also wonder what voltage rating that is needed for the 220uF caps?

Since they use the same components basically it would be interesting to know what you could not source. Are you thinking about the MPSA18s which can be substituted easily by almost anything?

[mats73]

No, I was referring to heatsinks and transformer, that I would prefer to purchase locally.

[UrSv]

Originally posted by mats73
No, I was referring to heatsinks and transformer, that I would prefer to purchase locally.

OK. For the heatsinks there is not much difference. A60 needs sinking for 200 W and Aleph 2 for 300 W meaning roughly 0.15 K/W for A60 and 0.1 for Aleph 2 and figures are per channel. Same kind of figures. As for teh transformers a 2*28 VAC for the A60 and 2*33-35 V for the Aleph 2 would probably do just fine and those are all standard. You can't source them?

You asked TEMA Elektronik to get them for you?

[mats73]

Hi again!
Well, I guess that they are kind of similar but since 60 Watt is going to be more than sufficent for my needs I thought I could save some money by choosing the Aleph 60.
The heatsinks however are a bit of a problem since finding ones rated at 0,3 C/W is easy(sold by ELFA). "Better"(as in bigger) than that I have to purchase from abroad.
I haven´t spoken to TEMA however and shall try to do so tomorrow and see what they can supply.
Thanks for the tip!

My original question still stands however, if anyone knows if it is possible to build the Aleph60 with "harvardians" boards?

And also the voltage rating for the 220uF caps!

Cheers
Mats

[Mad_K]

Big tip for you buying HS from Elfa: Buy 1000mm of the KS160, then get them cut to say 8pcs 125mm

220uF= Use the same as the rail-voltage (35V?).

[wuffwaff]

Mats,

yes you can use the boards. The amps are basically the same.

220uF caps are 6.3V or above for the one at -IN and the one in the current source. The bootstrapping C should be rated at 25V or above (the one parallel to the small bipolar transistor)

william

Oh and you could also do a search on this topic. This´ll help to make you a specialist in no time

[mats73]

Mads K: Yes I thought about that! Just have to see what the charge is for cutting the big HS for me.

Wuffwaff: Thank you! I have searched this forum a lot, but haven´t found "that" much info about the Aleph60.
When I look at both schematics I see a few thing that are different(aside from some componentvalues) however.
The capacitor marked C6 on the A2 schematic isn´t on the 60 schematic.

There is also no resistor on the input of the unbalanced connection on the A60.



Cheers
Mats

[Mad_K]

I got my KS160 cut for free at a local spray-paint/metalworkshop (Next time I will bring some ice-cream since they seemed crazy about that)

[wuffwaff]

Mats,

well C6 is easy......just leave it out when you build the 60.

The input configuration of the 60 and 30 are a bit different to give a higher input impedance for unbalanced sources. Here you can also leave the parts out that are not used in the 60 (I also use the 30/60 input configuration on my Aleph 5).

So building the 60 on a board developed for a 2 is no problem.

William

P.S. Oh yes R1 and R8 are in the 60 and not in the 2 but unless you have the possibility to measure the effect of these you can´t use them anyway (do a search on R1 R8)