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Old 22nd September 2010, 02:23 AM   #1
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Default Power output into 4 ohms

I'm confused , which sadly happens more then I'd like to admit. I'v searched though many threads and through google, but still the answer eludes me. If both the Aleph 3 and Aleph J operate in single ended class-a mode, why does one double it's power into 4 ohms and the other halve it's power.

Aleph 3 60w into 4 ohms

Aleph J 13w into 4 ohms

Thanks for any input

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Old 22nd September 2010, 02:37 AM   #2
tinitus is offline tinitus  Europe
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Originally Posted by habsrock93 View Post

Aleph 3 60w into 4 ohms
maybe only in AB, and not classA
sometimes we know very little, and sometimes we know too much
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Old 22nd September 2010, 03:01 AM   #3
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Its all in the Aleph current source setup.

You can adjust it if you want.
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Old 22nd September 2010, 06:31 AM   #4
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Ok, great. Thanks for pointing me in the right direction. I found the article "Zen Variations - Part 2, The Penultimate Zenís Current Source" It's a little late for a read now, but the title sounds promising
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Old 22nd September 2010, 10:22 AM   #5
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Location: Central Florida
The different sections of the Aleph amps are quite interchangable if you understand the different functions being used. I've just finished up a pair of monoblocks optimized for 4 ohms using the front end of the J and the output section quite like the 30 except with 3.6A bias and 55% AC current gain. It's quite easily done but does change the original design parameters so I just call them Alephs. They have bags of current capacity for difficult loads.
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Old 22nd September 2010, 05:04 PM   #6
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You can make an Aleph deliver beyond the Class A region,
but it's not pretty.

Wensan built a follower version that does the job - maybe he
will comment here for you.

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Old 24th September 2010, 06:09 AM   #7
wensan is offline wensan  United States
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Location: Milpitas
Here are the schematic and distortion curves of my SRPP power buffer what I built.
The bias current is about 0.75A.
The AC gain is about 85% in order to let it work in Class AB mode.
If the AC gain is 50%, it cannot work in Calss AB mode.
Attached Images
File Type: gif SRPP Power buffer.gif (14.5 KB, 181 views)
File Type: gif srpp damp.gif (4.8 KB, 173 views)
File Type: gif srpp dfrq.gif (5.3 KB, 173 views)
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Old 24th September 2010, 09:07 PM   #8
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Thanks Wensan

The other option worth considering is connecting up Aleph J with BA 2 Output stage.
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