ok let`s try:
I had the same questions. looked in the Service Manuals & some members told me that:
Aleph 3 & 30 pretty much the same
-both mosfet frontend
-aleph 3 -unbal Input, -2 Output pairs, -2.1A bias
-aleph 30 -Bal/unbal Input, -3output pairs, -1,6A bias
Aleph J
-jfet frontend -bal/unbal Input, -2output pairs, -bias in schematics not specified but 1,6A-2A bias should be ok.
The most difference in Sound is because the use of jfets / mosfets
in the frontend.
Mosfets- darker, more dynamic, Little bit more bass than J,
Jfets -more detailed, better top end, not so good bass.
Never heard a mosfet frontend Aleph, so not my own experience.
Hopefully i could help you
I had the same questions. looked in the Service Manuals & some members told me that:
Aleph 3 & 30 pretty much the same
-both mosfet frontend
-aleph 3 -unbal Input, -2 Output pairs, -2.1A bias
-aleph 30 -Bal/unbal Input, -3output pairs, -1,6A bias
Aleph J
-jfet frontend -bal/unbal Input, -2output pairs, -bias in schematics not specified but 1,6A-2A bias should be ok.
The most difference in Sound is because the use of jfets / mosfets
in the frontend.
Mosfets- darker, more dynamic, Little bit more bass than J,
Jfets -more detailed, better top end, not so good bass.
Never heard a mosfet frontend Aleph, so not my own experience.
Hopefully i could help you
I need your advice please about power supply for aleph 3. I intend to build it as bridge-CRC-voltage stabilizer. So i plan to output 35 V from CRC filter and than to decrease it by tl431+Mosfet in order to obtain +-25V. What are the disadvantages of this approach except power dissipation of 10 watts? Which electrolytic capacitors (model, brand) for the reasonable price will be ok in this power supply (22 000 uf) as it tends to be the most expensive part overall?
how you got to power dissipation of 10W ?
skimming - using (existing?) power transformer then caps with increased voltage, then decreasing voltage is recipe for bigger expenses than using proper xformer and caps from the start
18Vac secondaries will give you something as 22V5dc at caps , loaded onditions
to shave 35V to 25V , there is difference of 10V , multiplied with Iq ( at least 3A for two channels) and that's 30W per rail , 60W for both rails
that , not disputing way how you got starting figure of 35Vdc
don't get me wrong - I certainly tried more than zillion times either to skim expenses or simply to be smartjack , but sometimes most effective and most rewarding way is to do things as smarter guys are doing it
skimming - using (existing?) power transformer then caps with increased voltage, then decreasing voltage is recipe for bigger expenses than using proper xformer and caps from the start
18Vac secondaries will give you something as 22V5dc at caps , loaded onditions
to shave 35V to 25V , there is difference of 10V , multiplied with Iq ( at least 3A for two channels) and that's 30W per rail , 60W for both rails
that , not disputing way how you got starting figure of 35Vdc
don't get me wrong - I certainly tried more than zillion times either to skim expenses or simply to be smartjack , but sometimes most effective and most rewarding way is to do things as smarter guys are doing it
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first you need to chosse between snap-in and computer grade caps
first one are in economic range , second in expensive range
brands - usual suspects and you choose by availability ( price and level of complication)
Panasonic , Philips , F&T etc.
just go to mouser , digikey, Buerklin , TME ....... choose electrolytic caps , put 25V or 35V in filter , capacitance of your liking ( I prefer 33mF) .......say 15mF to 47mF (mF being miliFarad) then observe
according to these information you get there , you can look more locally , or buy from there
if in doubt , post here
first one are in economic range , second in expensive range
brands - usual suspects and you choose by availability ( price and level of complication)
Panasonic , Philips , F&T etc.
just go to mouser , digikey, Buerklin , TME ....... choose electrolytic caps , put 25V or 35V in filter , capacitance of your liking ( I prefer 33mF) .......say 15mF to 47mF (mF being miliFarad) then observe
according to these information you get there , you can look more locally , or buy from there
if in doubt , post here
....So i plan to output 35 V from CRC ...
If you have a trafo with enough VA (Watt) you can make a Aleph 60? It will have 35V rails
not so simple
room - speakers - how much watts and what type of amp
then - dissipation , so what case , what xformer , what caps , what bridges , what wires
can't have approach as with icecream - 2 or 3 or 4 spoons , big cornet or small one
there is a huge difference in hardware (kilos , money , size) between Aleph 3(0) and Aleph 60
room - speakers - how much watts and what type of amp
then - dissipation , so what case , what xformer , what caps , what bridges , what wires
can't have approach as with icecream - 2 or 3 or 4 spoons , big cornet or small one
there is a huge difference in hardware (kilos , money , size) between Aleph 3(0) and Aleph 60
Mine are still working, but still no face plate.
At last, My Aleph 2+
Build them and you'll be a happy man, but maybe with a not so happy wife.
At last, My Aleph 2+
Build them and you'll be a happy man, but maybe with a not so happy wife.
Hi. Some wrong when i try test aleph 2 with load 8 Ohm, look the sine wave form is not good. Did some one get problem like that ? what wrong with circuit?
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What's the amplitude on pics/test and post some pics of your build
Hi! thank .
Oh I build up Aleph 3 . at present i been outside now, i will post some pics when i back to try modify it...
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