Hey guys. I've decided to do this with my Aleph 5. Does anyone have anyone in the Bay Area to recommend doing this? I have a good tube guy who does work for me now and then but not so much for transistors. I suppose I could ask him. I've also worked with L&M Electronics and could try that.
Also, if I'm doing this I saw the recommendation on the clipping mod, any other relatively simple recommendations?
Is anyone replacing the caps with anything more exotic to good effect? If I'm having the thing ripped open this is the chance to do other things, I likely won't do this again.
I assume Pass Labs doesn't do this, and I'm not sure if Reno Hi Fi does mods, but I could get it over there if that was a route to get it done.
I'm driving Maggie 3.6qr's and perhaps 3.7s in a bit for context. I assume there is no easy way to add more output devices and leave the rest the same to help with 4-ohm high current handling
?
Also, if I'm doing this I saw the recommendation on the clipping mod, any other relatively simple recommendations?
Is anyone replacing the caps with anything more exotic to good effect? If I'm having the thing ripped open this is the chance to do other things, I likely won't do this again.
I assume Pass Labs doesn't do this, and I'm not sure if Reno Hi Fi does mods, but I could get it over there if that was a route to get it done.
I'm driving Maggie 3.6qr's and perhaps 3.7s in a bit for context. I assume there is no easy way to add more output devices and leave the rest the same to help with 4-ohm high current handling
?
sorry , I'm away of Bay Area in recent time , so my old contacts are sorta lost ..... 
..... but , besides techie thingy , I'll try to help :
clipping mod - nothing else than 5V6 zenner diode across C-E of Aleph CCS governing bjt (see attachment)
caps - huh , plenty of examples , even threads with same Aleph question ; answer would be - use good ones , as big as you can squeeze in ; bypass Aleph CCS modulation cap with something proper and fast (1uF MKC Philips being my Wild West Miracle Elixir thingie )
more cojones in output - that's more matter of heatsink and PSU capacity than matter of easiness
..... but , besides techie thingy , I'll try to help :clipping mod - nothing else than 5V6 zenner diode across C-E of Aleph CCS governing bjt (see attachment)
caps - huh , plenty of examples , even threads with same Aleph question ; answer would be - use good ones , as big as you can squeeze in ; bypass Aleph CCS modulation cap with something proper and fast (1uF MKC Philips being my Wild West Miracle Elixir thingie )
more cojones in output - that's more matter of heatsink and PSU capacity than matter of easiness
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I'm getting traction at L&M Electronics and will let you guys know how it goes. ZenMod - thanks for the info. I will poke around some more, and have done so. Thought there might be a simple consensus, i.e., get same value Deulands and be done with it. I'm not interested in a long journey there, and will take a good suggestion.
Nelson, if you are still there, would be curious if you have a recommendation on caps if the difference of a few hundred bucks here or there doesn't matter - mostly focusing on sound quality. I understand this is probably your least favourite kind of question, so I will expect it will be ignored, but if you wanted to chime in in regards to Aleph 5 it would be nice to know your opinion.
Nelson, if you are still there, would be curious if you have a recommendation on caps if the difference of a few hundred bucks here or there doesn't matter - mostly focusing on sound quality. I understand this is probably your least favourite kind of question, so I will expect it will be ignored, but if you wanted to chime in in regards to Aleph 5 it would be nice to know your opinion.
Also see http://www.diyaudio.com/forums/pass-labs/12923-top-ten-ways-better-aleph.html in this regard.
Great thread and I had forgotten about it. I particularly like #7 on
Mr. Pass' list:
http://www.diyaudio.com/forums/pass-labs/12923-top-ten-ways-better-aleph-2.html#post151736
Dennis
Yes - I eventually saw those caps recommended there and did indeed end up on the 10 things thread.
I was looking at Dueland for my Maggie Crossover and man, that comes out to thousands of dollars.... The one's mentioned seem reasonable. I don't mind some hundreds, but several thousands just for caps.... Oh man....
I was looking at Dueland for my Maggie Crossover and man, that comes out to thousands of dollars.... The one's mentioned seem reasonable. I don't mind some hundreds, but several thousands just for caps.... Oh man....
OK, here we go.
Last month I collected some "junk" Aleph 30's and 60's from the back shelves
of the storage space (the same one you remember from Raiders of the Lost Ark)
with the intention of salvaging the heat sinks drilled for TO-3 devices for use in
another project (yet another Sony SIT amplifier).
Opening them up, I discovered that they were in good enough shape that they
were worth keeping with a little cleaning and repair.
You will perhaps remember that I previously posted an update to the Aleph 3
which incorporated Toshiba 2SJ109 Jfets on the input stage, and while this
is still a worthy update there are two problems with it; first, it's difficult to
get these parts, and second, they only work on the lower voltage amplifiers
which leaves out most of the other Alephs.
However on these I decided to try my favorite small power Mosfets, the
Toshiba 2SJ313's. Apart from a different package and pin-out in some
amplifier models, they will drop right in as replacements, and they need to
be matched for Vgs at 10 mA.
The Toshiba's are preferred, but you can make do with other comparable
modern Mosfets if you can't get these parts.
Noting that some units had zener noise with R105 at 4.7K, I dropped that
value to 3.3K, and you will note that I optionally deleted Q104, the over-
current protection. Also, I moved the chassis ground connection directly
to the AC Earth ground.
The addition of the Toshiba Mosfets made for an immediate improvement
in power supply noise rejection, dropping it typically by a factor of 4 to 6, to
as low as 50 uV unweighted output. This alone justified the effort.
Also, as a tweak, you can replace the 220 uF caps with the silk caps from Elna.
Listening tests showed a significant improvement over the originals, and I
gave copies of these to my business partners for Xmas.
Hello everyone
,This version 2sj313 - is valid for Aleph2?
I would like to try in my amplifier.
Thank you!
Best regards.
Help to understand the feedback network
I made two aleph 3 monoblocks, they sound terrific.
I know that the relation between R104/R102 (10K/1K) sets the gain. I would like to understand why in the Aleph 30 Mr. Pass changed the relatives components to 100K/10K and in the Aleph J to 221K/21K.
I will thank if someone can teach me what more is involved with these two components.
Is there something with bandwith, linearity and dumping factor?
If so, could you explain how do they interact?
If is difficult to explaing here, could you link me to some reading that could help me to understand?
Thank you all
I made two aleph 3 monoblocks, they sound terrific.
I know that the relation between R104/R102 (10K/1K) sets the gain. I would like to understand why in the Aleph 30 Mr. Pass changed the relatives components to 100K/10K and in the Aleph J to 221K/21K.
I will thank if someone can teach me what more is involved with these two components.
Is there something with bandwith, linearity and dumping factor?
If so, could you explain how do they interact?
If is difficult to explaing here, could you link me to some reading that could help me to understand?
Thank you all