Aleph 3 Upgrade

[juanitox]

Hi all,
i have a stock aleph 3 in my garage ( still working ) i really love it's look and think of use it again in my main rig for a 8ohm medium/bass driver.
is there a benefit if put my hands on the engine or will it be a "sacrilege" 😀

i was thinking of changing the C power supply with CRC for start.
any other ideas ?

An externally hosted image should be here but it was not working when we last tested it.

 

[Zen Mod]

just replace all electrolytics with new ones

if you eager to search for some upgrade , look for it elsewhere , not CRC

read Aleph reloaded thread

 

[coolnose]

You could sell me that Aleph as well instead of butchering it...😎

 

[Zen Mod]

or just send it to OPLDF

🙂

 

[juanitox]

You could sell me that Aleph as well instead of butchering it...😎

you have no idea , i have killed so many , shame on me 😀

i will replace only stock electrolyte .... for the moment 🙂

 

[juanitox]

thanks to ZM , it's more clear for me now.

1 : changing 22000uf PS caps with 33000uf new ones
2 : changing stock C101 C102 C103 220uf with 470uf 100V Nichicon FG ( my favorite cap for porn) with 10nf mica or MKP bypass cap
3: delete TH1 ( chassis direct to ground)
4: and delete optional Q104

 

[Zen Mod]

if you can obtain Toshiba mosfets for LTP , change them too

of course , you'll need to recheck Iq and offset

I'm doing exactly that routinely , here in OPLDF , prior to tossing them in Da Presssssssssss

 

[juanitox]

if i want to go with the Input JFET version ( 2SJ109) , can i use a matched pair of 2SJ74 and in this place what it the correct Idss 6/7ma or more the best ? 🙂

 

[Zen Mod]

preferred current through each JFet is no more than 5mA , so somewhat higher Idss is good to have

 

[AVWERK]

There is no thermal compound on those U channels coming from the factory?
Simple enough to do while replacing caps

 

[juanitox]

i have just mesure the voltage across R106 and i have 5,8v on both side instead of the ( 4 to 5V ) on the schema is it too much ?😕

 

[Zen Mod]

ref. to which schematic ?

post it , then I'll tell you what is important to check ....... everything else is just of nominal value

 

[juanitox]

i have just realised that my unit has been already modified , with IRF 9510 on Q103 and IRF 9210 on Q101 /Q102 and i don't like that so i think i will buy a pair of IRF 9610 as original and go with LS J74 jfet for input ..

some works to do 🙂

 

[Zen Mod]

if you expect us to reply (sometimes) , we need to be on same page
so , you really need either to post or point to ref. schematic

so , is it this one : Medium Aleph 3 8ohm@20w.

 

[juanitox]

sorry for the delay , i have made a mistake with the 1K trimpot yesterday and two IRF9610 finished in flame :😡

so now i am trying to re build it with a pair of 2SJ09BL
i also have a pair of 2SJ313 is it worth to use it as regulator ( Q103) or shoukd i buy a a IRF 9610 ?

 

[Zen Mod]

for regulator use just ant P-channel TO220 you have in drawer ...... just anything from 510 to 740

using 313 there is sacrilege

 

[juanitox]

thanks Zen mod , always here for dumb guy 😀

using 313 there is sacrilege

that's why i will use it here !

 

[Zen Mod]

and you get lousier CCS using it , comparing to IRF

 

[juanitox]

and you get lousier CCS using it , comparing to IRF

that call me much, i have found a pair of SFP9610 instead 🙂

what is your favorite for input in aleph JFET like 2SJ109 or Mosfet ? any model not unobtainum ?

 

[KatieandDad]

Have you thought about upgrading the Aleph 3 to an Aleph 4. It wouldn't be a simple upgrade but the gains are enormous, especially in the extra headroom that the Aleph 4 has.