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Aleph J illustrated build guide
Aleph J illustrated build guide
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Old 12th February 2018, 05:59 PM   #2471
xrk971 is offline xrk971  United States
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Aleph J illustrated build guide
Quote:
now , make it without source resistors , and inform here

that would be news
Isn't the source resistor (R131), the Aleph current sensing monitor? It wouldn't be an Aleph without one. This one uses a P-channel on the bottom and Aksa Lender LNP (Long Neck Pair) input vs regular LTP.

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Last edited by xrk971; 12th February 2018 at 06:03 PM.
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Old 12th February 2018, 06:08 PM   #2472
Zen Mod is offline Zen Mod  Serbia
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I was (half) joking ........ I saw twists in that amp

btw. R132 , as shown on your schm. , is resistor important for Aleph CCS modulation ;

R131 is "just" source resistor
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Old 14th February 2018, 02:32 AM   #2473
Roo2 is offline Roo2  Australia
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Hello there,
I've ordered my Aleph J parts via Mouser. The BOM listed capacitor for C6, C7 has gone out of stock after I placed my order..
WIMA MKP2D031001F00JSSD, Mouser part number 505-MKP20.1/100/5
Could someone advise a suitable alternative that's in stock I could switch to?
If not, they're going to be back in stock early March so its not too long to wait.
Thanks
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Old 14th February 2018, 03:57 AM   #2474
6L6 is offline 6L6  United States
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Aleph J illustrated build guide
Roo2 - Honestly you can leave them empty and it not make any difference, those were added to assuage audiophile worries about un-bypassed electrolytic coupling caps, but if you want it won't hurt anything;

MKP2D031001F00KI00 WIMA | Mouser
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Old 14th February 2018, 09:36 AM   #2475
Roo2 is offline Roo2  Australia
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Thanks 6L6.
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Old 14th February 2018, 10:36 AM   #2476
Cyberkul is offline Cyberkul  Norway
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Hi! Thanks for these nice building threads :-)
I have an older E-core (?) transformer 2x21,5V, about 500VA. Can this be used with the Aleph J?
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Old 14th February 2018, 07:19 PM   #2477
Zen Mod is offline Zen Mod  Serbia
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oh yes !
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Old 14th February 2018, 07:58 PM   #2478
Mark Johnson is offline Mark Johnson  United States
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6L6, you have private message
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Old 14th February 2018, 09:55 PM   #2479
Cyberkul is offline Cyberkul  Norway
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Quote:
Originally Posted by Zen Mod View Post
oh yes !
Thanks!
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Old 18th February 2018, 09:13 AM   #2480
tommydoan84 is offline tommydoan84  United States
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Aleph J illustrated build guide
hi Jim and ZM,

I just bought gigantic heavy duty heatsinks. Much bigger than 5U deluxe heatsink that can keep things cool for higher bias. My DC rail supply is around 24.5 V (Using 500VA Antek toroid 20V-0-20V).

Do you foresee any issues if I crank up the bias to have 650mV across output resistor. This will give around 1.38 A to 33.8W/device. If my heatsink can keep output transistor thermal in check with this bias, should everything else be okay ?

Ultimately, is there a limit to how much biasing we can go achieve? I read from Alelph J manual, Nelson mentioned that max output current +/- 2.5A. What would happen if we exceed 2.5A ? I would assume there must be a very good reason that Nelson listed the max output current at +/- 2.5A

I'm curious to find out if higher biasing can result in better sound quality since distortion should ideally go lower based on your earlier measurement.

Let me know your thoughts and feedbacks
Thanks,
Tom
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Last edited by tommydoan84; 18th February 2018 at 09:39 AM.
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