Aleph 60 building thread

[toufu]

aleph2 is not aleph60. aleph2 is a 100W classA amp.

Thanks... Is Aleph 2 just an Aleph 60 with higher bias and rails?

 

[AudioSan]

yes. more or less

 

[PKI]

I am trying to map an original schematic onto the boards.

 

[toufu]

I am trying to map an original schematic onto the boards.

You don't have to do the mapping yourself. Just download the spreadsheet on chipamp.com and populate according to it.

 

[PKI]

From what I see they use different values for resistors, not original. Or I have wrong spreadsheet :-(

 

[AudioSan]

wich schematic are you looking at?

 

[PKI]

Original? -- from A60 manual. It should be in the first post. I do not have schematics for BGT boards.

 

[AudioSan]

remember that brian have only spreadsheet/schematic for aleph30. not aleph60.
so some resistor values will be different. like R19 and R21 from the A60 schematic. and R22-R27. A60 use 6x 1ohm. A30 use 6x0R47.

 

[PKI]

Ok, I got it. Will post correspondence tomorrow (for future DIYers). Have two questions: the value of R16(R17 on pcb) should it be 221 like on A60 schematics or 392 as in BrianGT spreadsheet? Another, there is no matching resistor R1* on the boards, only R8(R6), is it enough?

 

[AudioSan]

it is R18 on the PCB that is 392ohm. R17 is 221ohm.
you can do without the R1. its not used on the A2 or A30.
the whole front-end part is the same for all aleph's exept aleph-J. and exept bias and offset resistors. and the 3W resistors can go from 0R47 to 1R0.
other then that, all changes is in the output stage. as far as i know.

 

[PKI]

it is R18 on the PCB that is 392ohm. R17 is 221ohm.

Nope I am looking at the spreadsheet now: R17, R18 are 392, but with the comment: initial value, could be optimized for expected power/load conditions for R17.

 

[AudioSan]

on the schematic i got for A30, it is only R18 that is marked 392ohm. but i see R17 is marked 392ohm on the spreadsheet for A30. however. it is marked 221ohm on the A60 schematic.
so if it is A60 you are building. stick with 221ohm.

 

[PKI]

Thanks, I will go with 221 first and then will see!

There is only one thing between me and assembled A60 bock — wires. Bought 12awg teflon wires, but the strands are covered with some "silver" metal that does not soldering well :-(.

 

[AudioSan]

another reason to stick with good old trusty copper
i just take a extention cord wire with 3x1.5mm2 and strip it
but for the A60 you can go for something a little more beefy.

 

[PKI]

Guys, what to do with R19(R13 pcb). It's 5622?! I have a multiturn trimmer for 10k, or find something else?

 

[PKI]

okei. from the front end board to the first output board:
+c - +c. +v - +v. +g - +g. +s - +s. and then, from one output to another output:
+c -+c. +v - +v. +g - +g. and you are done same for the negative side

I have 12awg, 14awg and kimber 19awg wires. Which are better suit for +s, +g? I am thinking of 12awg for +c, +v and smaller diameter for other two.

 

[Danger Mouse]

Guys, what to do with R19(R13 pcb). It's 5622?! I have a multiturn trimmer for 10k, or find something else?

I think its 56,2k

Seen this kind of number in x2 manual.
means 562 and 2x 00 is 56200ohm
Last digit says how much 0 you must add

could also be that i`m wrong

 

[PKI]

I think its 56,2k

Seen this kind of number in x2 manual.
means 562 and 2x 00 is 56200ohm
Last digit says how much 0 you must add

could also be that i`m wrong

Is this true?! :-( I was thinking that this is just 5.62k, no?

 

[Danger Mouse]

Is this true?! :-( I was thinking that this is just 5.62k, no?

look there

http://www.diyaudio.com/forums/pass-labs/58758-pass-labs-x2-rev1-relays-2.html#post2518092

I think Pass forget to translate R19 and R21.

When I will do my Aleph60 I will try R21 1,5k and R19 56,2k
I`ve looked at the serive manual from the Aleph30 there R19 is 47,5k
why should it be so much different in the 60?

I will try when time is come hopefully my Amp dosn`t burn down

greets Alex

 

[Zen Mod]

5622 means 562 x 10^2 = 562 x 100 = 56K2