ditch this design for an Aleph2?

[cHoc]

hi all, i'm new here' and lurked around for a few days now, and registered.

And I have an question;
I'm now builing an amp (4x mono amps) from this design http://www.arky.ru/audio/shem/igbt/igbt.htm, and i've reached the point where i now have the 4 pcb's with all the resistors an capacitors and so on, but still need the transformers, the IGBT's and two more heatsinks and the housing for it, so also rather expencive material to finish it.
And i'm wondering if i better ditch it in favour of an Aleph 2 now, or go on building it for experiance, althow this amp and the Aleph are totally different in design.

And what could or might i learn from it what i can use when i will start building an Aleph.

fyi: if i deside to continu building this amp it will be ditched directly for the Aleph 2 when ready (and Aleph P)

I myself are leaning towards ditching it and start directly with the Aleph.

someone who can help me decide??

[Mark A. Gulbrandsen]

I'd say in the long run go ahead and build both of them. Finish one of these in a stereo config. first, and then build a pair of Aleph 2's. You gain experience in both of them and in building things. Remember this can still be somewhat expensive to do. Nothing thats really good is cheap, even if you DIY. You do save alot of $$ though, and its also possible to build it better than the production version of what ever it isd you are building. Thats a big advantage!

I've owned alot of amps in my life so far and the DIY Aleph 2's blow all the other amps to heck. That includes KSA 80, BAT VK-60, Several ARC tube jobs...and yes, an S-300 Threshold. The Aleph experience is quite different than anything you've ever listened to.....
Mark

[cHoc]

Thanx for your reply Mark,

I thought it over for a while, and desided to make it after all,
but not with the IGBT's, Elektor also made this design for the IGBT's but they were not available for them at that time so they desided to take a pair of Hexfet's instead, and later with the IGBT's.
This design also fits on the same pcb, so no worry there, and it's slightly cheaper because of the hexfet's price and a smaller transformator (160VA instead of an 225VA).
The only differences are some minor cheap elements to replace for the hexfet version.

so it will be finished faster, so i can start on the new project.

[Samuel Jayaraj]

I'd be very happy for you if you get this amp to work reliably with IRF9540 and IRF540 (as per Elektor's earlier publication). I have four assembled PCBs lying with me. I don't intend to look into the problem with this amp for the time being.

This amp sounds reasonably good but will certainly not match any of the Alephs. However, the problem is that the amp, while in operation suddenly goes into a burst of oscillation, damaging the tweeter. If you do have a peak indicator or protection circuit, this gets triggered on and the amp needs to be switch off. When switched on again, all is well. This has happened in two of my boards and I didn't care to try the other two. It has repeatedly happened to a friend of mine who also built this amp. Perhaps, the IGBT version is better. In any case, give it a try. You need the experience of building something as simple as this before you venture to build Aleph2s.

[cHoc]

maybe that has to do with the coupling of the BC550 and BC560, in an earlier design of Elektor, they mention that trying in this direction does not give good results.
Maybe you could switch them for an SSM2210 and SSM2220 wich has two BC550 cq BC560 in one neat DIL8 housing with for this design don't need any power, just implement them and ready you are.
I did not test this yet, so don't know if it would be an solution, but it will surely inprove over couppeld BC550/560.

or also, if you don't like DIL packages, take MAT02/03 instead but more expensive