Another Aleph finished!

Hello,

Here 4 pictures of my almost finished Aleph 4. Is it an 4 which has a bit higher bias and a change in the current source gain, to get a bit more punce in the bass department!

The inside is still a bit of a mess, because I ordered some professional made PCB boards which I will build with blackgates and holco's in the future. So I did not put much effort in cable guiding and stuff like this!

I sounds wunderfull and an absolute minimal of hiss and hum.

[IMGDEAD]http://www.xs4all.nl/~edwind/aa.jpg[/IMGDEAD]

[IMGDEAD]http://www.xs4all.nl/~edwind/bb.jpg[/IMGDEAD]

[IMGDEAD]http://www.xs4all.nl/~edwind/cc.jpg[/IMGDEAD]

[IMGDEAD]http://www.xs4all.nl/~edwind/dd.jpg[/IMGDEAD]

Thanks,

Edwin
 
Now that's a seriously good looking amp. Silver and black always look better than one colour. Have some questions:

I see you used thermistors in series, what's the reason?
What about those fans on a side?

I finally see properly done output stage wiring. No PCB and p2p, that's the best way to do it.;) Nice looking switch on front panel too. Where is it sourced from?
 
I am in the process of typing a piece of text for the diypass website! But here are some battle stats ;-)

2x 1000VA 40-0-40
16x 22000uf 63V

which gives about + / - 49.8V of loaded voltage, 52V unloaded!

P2P done with silver wire. The other pieces of wire are not very good but will be replaced with silver when kristian's PCB's are ready. I still have to find a good source for holco's where I can buy with creditcard.

I could not find 10 ohm thermistors, so 2x 5 ohm in serie.

The fans are there for safety. It is about > 33 degree celcius here at the moment :-(

I am very very happy with the switch. It is a vandal prove RVS switch with a micro-switch behind it. I use a bi-stable relais to switch it on and off with each click. I bought both at www.conrad.nl ! It looks like the same switch ( I think ) Nelson uses for his X150 amps! :)))
 
Peter Daniel said:
It's more like a temperature meter. How those heat sinks behave, seem kind of small for Aleph 4 with incresed bias.;)

it is a temperature meter! They are fischer SK435 blocks. Four of them! 200mm x 215mm x 80mm with a 18mm base plate!

So they are not that small :)

They behave good, but indeed a bit too hot. about 62C with a room temperature of 26C ..

Edwin
 

lieven

Member
2002-08-11 4:42 pm
Belgium
how does it sounds compared to the luxman in the background?

Where did you get those trafo's and heat-sinks???

Verry nice, my complements!!!

As Peter mentioned, don't change output-stage wiring, it can't be nicer. (pcb is a way to have equal quality, not better...smd is even worse)

Got a ESS amp wired that way, even a Soundcraftsmen ma 5002a wire-wrapped, still working (both lightly modified)
 
lieven said:
how does it sounds compared to the luxman in the background?

Where did you get those trafo's and heat-sinks???

Verry nice, my complements!!!

As Peter mentioned, don't change output-stage wiring, it can't be nicer. (pcb is a way to have equal quality, not better...smd is even worse)

Got a ESS amp wired that way, even a Soundcraftsmen ma 5002a wire-wrapped, still working (both lightly modified)

The amp on the back is a Denon AVR3801. Only used for DVD movies which drives my back and center speakers. I use pre-out to my Aleph P for the front speakers.

My precious amp was a Classe CAP-151 integrated. The Aleph P + Aleph 4 wins ... ;-)

I bought the heatsinks from Texim, haaksbergen and the trafo's from Amplimo.

Edwin
 

trigon

Member
2002-05-09 4:35 am
Canada
Excellent job.

All compliments. Very impressive and I hope as well excellent sounding engine?

I have PCB's for Aleph 4 (mono block version) which I have ordered from PCB-Design (Kristijan) and they really look excellent.

Slowly completing my Aleph 4 but way far from finishing. May I ask you kindly if you can measure Voltages on 220uf capacitors, just curious as I have asked in an earlier post if I can use FK Series Black Gate capacitors 220uf/25V. ;) Thank you in advance.

Congratulation one more time, looking forward to see DIYPass web site with additional Aleph 4.

Trigon.:)
 
Peter Daniel said:
What kind of rectifying bridges are you using? I'm asking because I had some problems in the past when bridges blew because thermistors didn't provide enough inrush protection. I also tried puting them in series because of that. You seem to have a lot of capacitance to deal with thou.

I used 2 times 25A 600V bridges. One for each channel, with all diodes of the bridges bypassed with a .47uf MKP. They are bolted to the floor of the amp.

Edwin