200w Aleph-X equals Aleph 1.2

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Following Nelson's previous 'advice' I'm assuming that'll whether it's an Aleph 1.2 or a 200W Aleph-X. The beg, borrow, and or otherwise apply as much heatsink as you can find rule will apply!

The lower rail voltages may make it easier to find large doses of capacitance 'lying around'. I still have 28 of the 68,000uf Stubby's leftover from my Aleph 5 project. As soon as I complete my Aleph ala Kristijan's board and power supply design I'll see how the CLC works and go from there.

Regards,
Dan

P.S. Thanks for the input Nelson.
 
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Following Nelson's previous 'advice' I'm assuming that'll whether it's an Aleph 1.2 or a 200W Aleph-X. The beg, borrow, and or otherwise apply as much heatsink as you can find rule will apply!

The lower rail voltages may make it easier to find large doses of capacitance 'lying around'. I still have 28 of the 68,000uf Stubby's leftover from my Aleph 5 project. As soon as I complete my Aleph ala Kristijan's board and power supply design I'll see how the CLC works and go from there.

Regards,
Dan

P.S. Thanks for the input Nelson.
 
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After finishing my Aleph 5 in the near future. I may be enticed into starting to prototype a 200W Aleph-X power supply. It looks like the 1500VA Plitron toroid will be about $200CAN/$155USD. I think I have enough surplus capacitance and heatsinks to mock up a single monoblock. Anyone interested this particular experiement?

Regards,
Dan
 
What I would like to know is how does N.P. get double the power at 4 ohms out of the production amps? I would assume that they must be designed to deliver however much power at 4 ohms and then you just end up with less, or about half that at 8 ohms. He's got to be building huge high current supplies, much larger than anyone here has thought about building as of yet.......
Doesnt his 200 WPC XA use two 1.5 kva trannies?

Mark
 
I think the trick used by many amp producers is to under state the 8 ohm power so it is half of the 4 ohm power. Except for pure class A and amps with fully regulated power supplies, there will always be some voltage sag.
With SE class A amps, the voltage sag is already there at idle. As long as the bias current is there, the amp will double its output when the imp is halfed.
 
Mark,

In the case of the XA 200 my understanding from the literature is that it will not deliver more power into an impedance lower than 8 ohms.

You would need to refer to Passlabs for for specific information regards power/load deliver factors.

This issue is however not the case with the Aleph series which driver more power into lower impedances, but not double the power for 1/2 the load.

My your own point of view, design the class A bias/max volts output aound your speaker parameters and be a little conservative so as to allow for losses in the design.

There are plently of refererences and useful spreadsheets in the various X Aleph threads to assist here.


macka
 
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. He's got to be building huge high current supplies, much larger than anyone here has thought about building as of yet.......
Doesnt his 200 WPC XA use two 1.5 kva trannies?

Mark

To counter Mark's statement. I am seriously thinking of pursuing a 200W Aleph-X and I see the power supply as the least of my challenges. The 1.5kva transformers are readily available at Plitron who are only 30 minutes from where I live. I have enough surplus capacitance kicking around to get going. I would probably get some of the 68A IXYS bridge rectifiers from Percy Audio (ouch! $100USD). I have access to some nice oscilloscopes and mult-kilowatt load resistors. And I'm sure Nelson would keep dropping crumbs along the trail to make sure we wouldn't get too lost in the woods. He's already 'hinted', and I quote,
"It will generally have 1/2 the rail voltages, and twice the
current draw, otherwise the amount of hardware tends
to be about the same. The XA200 also has twice as much
capacitance, in an RCLC filter set.

The power supply aside. The 200w Aleph-X facinates me for a number of reasons. Not the least of which being it is well beyond my particular abilities at this time. To complete just such a project by I would need a number of things including the support of the forum. It would be a risky personal challenge thing for myself. I would setting a goal well above anything I've done before and rolling the dice. But, I guess that's the part that intrigues me the most. Without taking any risks I will never find out just how far I can go.......

Regards,
Dan
 
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