DVBjunky said:
Easy enough to anodise yourself. (+cheaper)
Some state they can run TO220 rectifier diodes at +2A without a heatsink while remaining luke warm, others say they become as hot as their g/f .
That weird Serb even got me to eat Balk-On food, strange enough for ya ?
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Hey Jacco and Choky,
what about a wooden case with the Seifert heatsinks?
I'd like to cut a large cube from MPX for my AJ monos.
40 x 40 x 40 cm.
The Seiferts are the ones from analog forum's group buy.
It should get an open bottom and a hole of 10 x 30 cm
on the top of the rear.
So the hot air should be able to convect though the casing.
Possible?
what about a wooden case with the Seifert heatsinks?
I'd like to cut a large cube from MPX for my AJ monos.
40 x 40 x 40 cm.
The Seiferts are the ones from analog forum's group buy.
It should get an open bottom and a hole of 10 x 30 cm
on the top of the rear.
So the hot air should be able to convect though the casing.
Possible?
400VA is a fat boy for a single A-J channel, and a skinny thing for stereo.
Average price difference between a 225/250VA and a 300VA is marginal (same toroid core size, etc.).
Butta a 400VA toroidal will easily cost 25% more than the 300VA model, and $25 difference buys a lot of 35V electrolytics.
Getting hit on the head by a 400VA transformer each time on entering a storage is not identical to having to order a toroidal for a single project.
TickTock,
The Seifert heatsinks have a fin spacing of ~15mm, they will not perform better in a chimney effect set-up than fully out in the open.
But it will look very pretty, with a wooden encasing even prettier than the (chromed) Neumann A300M i posted a link of at AAA.
With the heatsinks between the amp channels and built as fully dual mono it will be close to identical to having mono amps.
There's a seller at E-quack who offers rolls of copper foil at a very attractive rate, in case you fancy a bit of shielding on the inside of a multiplex woody case.
Average price difference between a 225/250VA and a 300VA is marginal (same toroid core size, etc.).
Butta a 400VA toroidal will easily cost 25% more than the 300VA model, and $25 difference buys a lot of 35V electrolytics.
Getting hit on the head by a 400VA transformer each time on entering a storage is not identical to having to order a toroidal for a single project.
TickTock,
The Seifert heatsinks have a fin spacing of ~15mm, they will not perform better in a chimney effect set-up than fully out in the open.
But it will look very pretty, with a wooden encasing even prettier than the (chromed) Neumann A300M i posted a link of at AAA.
With the heatsinks between the amp channels and built as fully dual mono it will be close to identical to having mono amps.
There's a seller at E-quack who offers rolls of copper foil at a very attractive rate, in case you fancy a bit of shielding on the inside of a multiplex woody case.
Here's something I'm playing with. It's a bridged version of the Aleph J. It's balanced and, I believe, the feedback is symmetrical.
The sim says it's output is 145 watts RMS. It seems to swing 40 volts peak to peak when I run the voltage differential on R27. The power resistor values could be halved if twice as many fets were used. My sim (free from SIMetrix) has limits on circuit size, so I can't build up the circuit to full capacity. As it stands the fets are handling 50 watts of power--a bit high, but not totally ridiculous.
The sim says it's output is 145 watts RMS. It seems to swing 40 volts peak to peak when I run the voltage differential on R27. The power resistor values could be halved if twice as many fets were used. My sim (free from SIMetrix) has limits on circuit size, so I can't build up the circuit to full capacity. As it stands the fets are handling 50 watts of power--a bit high, but not totally ridiculous.
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carpenter said:
Because I'm learning????????
there is no better reason for that , certainly ;
but - you can use LM3886 model for that (bridging) exercise ....... with lot less mouse moves and kbrd tickin'
(NB - I worship ya - I never learned to simulate .......... maybe I need to prolong my first tries ......... to more than 10 mins .......
naah ..... I'm hopeless
)
Blues said:Try with one differential front end, John. Keep the other 2 jfets for the other channel
I tried, Blues, and couldn't get the sine wave even top and bottom. Then I got the bright idea that two differentials might do the trick. Of course, I ended up with a bridge amplifier circuit, but what fun!! I now know how to build a great, balanced, powerful, bridged Aleph J...
As for my Serbian friend, Love ya, Choky.