Aleph P 1.7 distortion/clipping? - diyAudio
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Old 16th May 2013, 04:48 PM   #1
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Default Aleph P 1.7 distortion/clipping?

Hi, i have a problem with my Aleph P 1.7. When i closed the input switch with 10k i get distortion sounds like clipping the amplifier. Is this effect normal? Gives modifications from Nelson for the P 1.7? Other gatestoppers? I have read this problem is not a single problem, but i did not find a solution.


With best regards
Christopher
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Old 16th May 2013, 05:24 PM   #2
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you are not alone with this problem. i have never tryed mine with bypassed 10K's. but do you have a gain pot? R36 on KK's PCB's.
i also have some noise issues with mine. but it seams to relate to the volume Control.

EDIT: my noise issues is now gone. gone like the Wind. it was a groundloop issue.

Last edited by AudioSan; 16th May 2013 at 05:39 PM.
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Old 16th May 2013, 05:30 PM   #3
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Yes, i have the gain pot but the clipping is not in correlation with the gain. A new info is, that the Aleph is clipping by 2V input and loves 0,7V input. But i have read, that Nelson has modified the gatestoppers. Is it true?
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Old 16th May 2013, 05:40 PM   #4
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i don't know. maybe nelson can answer this? or ZM
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Old 16th May 2013, 06:13 PM   #5
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Nelson? Can you help us, please? Gives mods for the Aleph P 1.7?


Best regards
Chris
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Old 16th May 2013, 07:04 PM   #6
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but do you realy need more then 9.7db gain?
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Old 16th May 2013, 07:09 PM   #7
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The gain is not my problem, but i want to know whats going on and is the clipping normal or is it a problem from the fetīs.
And its intresting to know for improvements

Last edited by chris86; 16th May 2013 at 07:15 PM.
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Old 16th May 2013, 07:58 PM   #8
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Sounds like my problem look here Aleph1.7
or here Pictures of your diy Pass amplifier

I`ve solved this with placing a 221Ohm resistor at input befor the zener diodes.

Same problem is reproducible at bosoz by delete the 221hm resistor befor the Zener (i`ve tested).
Look at the Bosoz article and read what happens if you delete R18/19.

But dont know how this is solved in origin.
I think this 221Ohm is maybe on the input selction Board and is gone lost in the service manual
or he uses friendly zener diodes

or this problem is totally different from mine... than i dont know
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Old 16th May 2013, 08:38 PM   #9
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Thanks for helping me but i canīt follow now. Can you share a schematic, please? Or we contacted in german, i think it is easier
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Old 16th May 2013, 08:49 PM   #10
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Ah now... do you mean a additional R with 221R to set behind the 10k R and than i can switch the 10k out of the system. Is it correct? It looks like same with the input from BOSOZ...?
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