Well Here is another Aleph 2 proect nearing completion.
Just a quick look before they are painted and engraved
It was a bit scary to start with, all the heat and power, but I'm getting use to it now! The pair of them take the chill off the room quite nicely!
As you can see I went for the rectangular aluminum chassis like many of the other Aleph 2 clones.
The design however evolved (with the help of my father - a retired engineer) is based on heat and size requirements for the internals and uses alumimium 3mm plate and L section, the heat sinks used tapped with M3 stainless bolts, the rest uses M4 stainless hardware.
The boxes measure 400mm long, 260mm high and 400 wide (incl heatsinks). My guess is they are about 28 KG in mass.
There are a couple of nice features, some venting at the sides using slots of about 4 x 400 mm above and below the heatsinks,and the lower box to enbles the power supply to benefit from the cooler air .
The heatsinks are Conrad 0.21C /watt and run at about 48C, the internal temperature in the upper chassis is about 43C and the lower chassis about 30C.
Most of the parts are stock Digi-key as you can see, the small caps are Silmics. The power supply uses E Bay NOS SAMHWA
8 x 15,000 uf 63 volt 85c which seem fine, with a 1KVA toroidal from Antrim and the Elector soft start circuit which is great. The transformers are a bit noisy at times due to mains born noise and their high flux, but with the lid on its quite reasonable.
The power supply uses 1mm copper sheet and in some areas I used teflon coated 20 amp silver plated standed cable. I after 1 hour or so warmup I have trimmed the bias for 3.00 amp with the lid on (using the blue trimmers) and have trimmed the current share for 50%.
I tried to keep the wiring to a minimum and with some symmetry to the layout. The project was an interesting and valuable journey, and certainly a valuable learning curve.
Please thanks to Mr Pass for his assistance and re assurance.
They perform very well and are appear very accurate and perhaps more so than Aleph 5 I made earlier, namely in the bass which is more defined and they also seem to have a more neutral and accurate tonal structure.
Cheers
macka
Just a quick look before they are painted and engraved
It was a bit scary to start with, all the heat and power, but I'm getting use to it now! The pair of them take the chill off the room quite nicely!
As you can see I went for the rectangular aluminum chassis like many of the other Aleph 2 clones.
The design however evolved (with the help of my father - a retired engineer) is based on heat and size requirements for the internals and uses alumimium 3mm plate and L section, the heat sinks used tapped with M3 stainless bolts, the rest uses M4 stainless hardware.
The boxes measure 400mm long, 260mm high and 400 wide (incl heatsinks). My guess is they are about 28 KG in mass.
There are a couple of nice features, some venting at the sides using slots of about 4 x 400 mm above and below the heatsinks,and the lower box to enbles the power supply to benefit from the cooler air .
The heatsinks are Conrad 0.21C /watt and run at about 48C, the internal temperature in the upper chassis is about 43C and the lower chassis about 30C.
Most of the parts are stock Digi-key as you can see, the small caps are Silmics. The power supply uses E Bay NOS SAMHWA
8 x 15,000 uf 63 volt 85c which seem fine, with a 1KVA toroidal from Antrim and the Elector soft start circuit which is great. The transformers are a bit noisy at times due to mains born noise and their high flux, but with the lid on its quite reasonable.
The power supply uses 1mm copper sheet and in some areas I used teflon coated 20 amp silver plated standed cable. I after 1 hour or so warmup I have trimmed the bias for 3.00 amp with the lid on (using the blue trimmers) and have trimmed the current share for 50%.
I tried to keep the wiring to a minimum and with some symmetry to the layout. The project was an interesting and valuable journey, and certainly a valuable learning curve.
Please thanks to Mr Pass for his assistance and re assurance.
They perform very well and are appear very accurate and perhaps more so than Aleph 5 I made earlier, namely in the bass which is more defined and they also seem to have a more neutral and accurate tonal structure.
Cheers
macka
