Well, I do. I just hauled Alephj upstairs where vinyl system lives. BA3 FE, Pearl 2...this is where M2 resides. Fierce battle taking place. Tough two to judge, two delicious flavors.😎 This will take some time.
First blush, too early in contest really, but seems M2 more controlled, J being flavor of edging towards more bloated in a very pleasurable way. Both warm amps and my two favs.
While all First Watts are great, F5 a little sterile, not overly so, it was amp that made me see my way to sell beloved McIntosh 225. F6 excellent, but to me, and maybe me only, least enjoyable, but...very enjoyable all things considered. These are not criticisms, just tonal observations held up against my opinions, nothing more. If I was "stuck" with F6 that would not be bad at all. I really like my BA3, really like it fine. That said, M2 and Aleph j are very special. M2 not as soft on top, not bright, very warm in fact. Aleph j slightly softer on top, but nothing missing, just in comparison. Aleph J has a magic, in different way than M2. Slightly overblown, perhaps it Aleph single ended nature which I am finding addictive.
Yes Zenmod, all should own both. Now I wonder about Bablefish, and J2....it's outputs waiting in drawer until schematic released.
Russellc
First blush, too early in contest really, but seems M2 more controlled, J being flavor of edging towards more bloated in a very pleasurable way. Both warm amps and my two favs.
While all First Watts are great, F5 a little sterile, not overly so, it was amp that made me see my way to sell beloved McIntosh 225. F6 excellent, but to me, and maybe me only, least enjoyable, but...very enjoyable all things considered. These are not criticisms, just tonal observations held up against my opinions, nothing more. If I was "stuck" with F6 that would not be bad at all. I really like my BA3, really like it fine. That said, M2 and Aleph j are very special. M2 not as soft on top, not bright, very warm in fact. Aleph j slightly softer on top, but nothing missing, just in comparison. Aleph J has a magic, in different way than M2. Slightly overblown, perhaps it Aleph single ended nature which I am finding addictive.
Yes Zenmod, all should own both. Now I wonder about Bablefish, and J2....it's outputs waiting in drawer until schematic released.
Russellc
Hi there, I'm ordering parts for my AlephJ.
R30 - Resistor or jumper?
I see it's a jumper in the build photos. When might it need to be a resistor and how is the value determined?
Thanks, Andrew
R30 - Resistor or jumper?
I see it's a jumper in the build photos. When might it need to be a resistor and how is the value determined?
Thanks, Andrew
The hardware usually comes with the transformer (at least from Antek). What transformer are you using?
Edit: Oops I though you meant the transformer.
Edit: Oops I though you meant the transformer.
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I have a Toroidy unit which came with a mounting plate but no screws. Looks like I can source some type of standoff then screw them down. Was hoping to use something similar for the universal ps board as well
For Aleph fans - a new variant called the ALPHA, that has stellar performance is described over in SS forum.
Aksa Lender P-mos Hybrid Aleph (ALPHA) Amplifier
Here is 20W version (UMS heatsink compliant):
First measurement at 2.87vrms into 8ohms with 1.3amps bias looks very promising. A 52W version is in the works.
Oh, and don’t worry, you can still use flying leads (big pad provided) as the spade connectors are optional. Big plus is also fact that components are as cheap as chips. No unobtanium JFETs here, just KSA992,KSC1845, BC547 and IRFP240/9240 or similar for outputs.
Aksa Lender P-mos Hybrid Aleph (ALPHA) Amplifier
Here is 20W version (UMS heatsink compliant):
First measurement at 2.87vrms into 8ohms with 1.3amps bias looks very promising. A 52W version is in the works.
Oh, and don’t worry, you can still use flying leads (big pad provided) as the spade connectors are optional. Big plus is also fact that components are as cheap as chips. No unobtanium JFETs here, just KSA992,KSC1845, BC547 and IRFP240/9240 or similar for outputs.
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now , make it without source resistors , and inform here
that would be news
🙂
as I remember , Juma tried and made BJT input Aleph several years ago
that would be news
🙂
as I remember , Juma tried and made BJT input Aleph several years ago
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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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
btw. R132 , as shown on your schm. , is resistor important for Aleph CCS modulation ;
R131 is "just" source resistor
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
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
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
MKP2D031001F00KI00 WIMA | Mouser
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?
I have an older E-core (?) transformer 2x21,5V, about 500VA. Can this be used with the Aleph J?
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
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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