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Old 28th August 2005, 03:49 PM   #1
jeapel is offline jeapel  Canada
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Default aleph or not aleph

hi

For the mini A or aleph 3 i would like to know if
someone try just for testing to remove the 220uF
for current modulation and to get just a ccs and
hear the sound what is the difference ok the
output power is not the same but just for the sound.

thanks
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Old 28th August 2005, 05:55 PM   #2
Blues is offline Blues  United States
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I'm sure Mr. Pass has tried it and we all know he put it back in. The CCS feedback makes the Aleph have more headroom and would be more speaker friendly. We all know all speakers' impedance are not flat across the audioband and will occassionally dip depending on the program material.
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Old 28th August 2005, 08:18 PM   #3
jeapel is offline jeapel  Canada
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hi

-more power and more speaker friendly sure

-but to get no dip with frequency you need a low zout and

the global feedback give a low zout but you tell me

the ccs feedback give also a low zout
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Old 28th August 2005, 08:47 PM   #4
winslow is offline winslow  United States
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I thought that I read an old post where it was said the CCS would have benefits on the topend.
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Old 28th August 2005, 09:09 PM   #5
jeapel is offline jeapel  Canada
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hi winslow

newbie with old questions it s possible :-)

but the conclusion was ??

thanks
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Old 28th August 2005, 09:30 PM   #6
winslow is offline winslow  United States
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I'm a newb too...looking for the post now, but can't find it. I thnk the suggestion was try it and see if you like it. But I'm curious as well. Hopefully you'll have better luck with people helping you out than I have around here.

Maybe it was here-

The effect of the ac current gain in Aleph
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Old 28th August 2005, 10:07 PM   #7
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There's not that much consensus on the best setting for an Aleph
current source. We have played with it anywhere from 0 (CCS)
to 100%. The listeners we have tested with seem to have
preferences ranging from about 30% to 70%, but this figure
encompasses different speakers, music, levels, and taste.

50% gives the best efficiency figure, but the optimum gain
sonically depends on the above variables and also the bias.

As you go toward 0, you must double the bias in order to reach
the same power spec, and typically increase the feedback by
12 dB or so to maintain a similar distortion spec.

As you go toward 100, you must also double the bias to remain
in Class A, but you can get theoretically get "vanishingly low"
distortion with such an approach.

If you don't increase the bias as you increase the gain, you will
run into cutoff on the current source at higher power levels, and
it's not pretty.

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Old 29th August 2005, 12:16 AM   #8
jeapel is offline jeapel  Canada
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thanks Mr. Pass

I just print out your answer with all possible variations.

The truth is often suprising the most for me is lower
distortion with aleph current modulation.

a newbie meet a star wow! great forum :-)
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Old 29th August 2005, 01:06 AM   #9
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If you look at the current modulation as feedback, it's not too hard to see how it can lower distortion.

Grey
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Old 29th August 2005, 02:22 AM   #10
winslow is offline winslow  United States
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Doesn't the new Aleph J do away with all capacitors in the signal chain?
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