Aleph J illustrated build guide

Official Court Jester
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PSU board can be made with intention to be connected to chassis through standoffs, and can be made intentionally not to have connection with chassis through standoffs

which arrangement is going to be used, well, that's planning

I know that some of Pa's PSU pcbs are made in one way, other are made in second

though, me still lacking lifetime or two to reach Papa's level (of whatever), I'm still Chicken so all mounting holes on my pcbs being well isolated from anything else on pcb

(I'm cheating, just realized that I have two thingie pcbs having deliberate contact with chassis ..... planned :rofl: )
 
Hmmm, are you using the diyaudio store PSU boards? I thought the mounting eyelets are not connected to the ground plane on those. I might be wrong of course as I am lazy to open my amp and check!:rolleyes:
No, I'm using the BrianGT "Mini-Aleph" PSU and amp boards.

As I hauled the amp back to the bench, I doubted that the diyAudio board was designed that way.

But there is more fun yet to be had - I've come full circle and bias and offset have a mind of their own again. I'm about to throw this heap in the lake.
 
Have a look at the attached photo... see which way works better for you. Leave a piece of wire hanging... and then try:

a) feeding the shield wire to the PCB GND (in my case this worked better - I liked it better sound-wise)
or
b) terminate the interconnect shield straight to the chassis (still okay, and according to Rene - the correct way to do things...) - and do not feed it to the PCB GND

I did not have any hiss or buzz when I tried either a) and/or b)... nothing - like the amp is not ON at all.


IMG_3836.JPG
 
@Extreme_Boky
What does the job of inrush current limiting in that amplifier?

Edit:
And where are the rest of the wires...some type of Tesla power transfer?

The wires are very short and are soldered wherever possible. I do not use CL60 between PCB common, and chassis. Just short, multistrand wire...

The green arrow -> The mains (primary) wires, total length probably 2 inches.... tucked underneath the transformer mounting plate.
The red arrows -> The inrush current protection CL60. The CL60's legs are used and soldered directly to the IEC filter lug connectors.
White arrows -> The connection between PC PCB common and the chassis.
Black arrows -> The secondary wires, twisted and soldered from underneath of that PS PCB. Shortest possible length, tucked underneath the transformer metal plate (and sandwiched between the PS PCB and chassis).

IMG_3764.JPG



PS PCB 3.jpg



IMG_4046.JPG
 
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I bought the PCB of the amplifier, power supply and transistors in the DIYAUDIO STORE.
The whistle in the speakers 2 seconds after power off is still there. I corrected all soldering points - no result.
I measured the max voltage at the loudspeaker terminals during the whistle:
AC=1.8V, DC=0.0V.
 

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Can a whistle voltage of around 2V RMS damage the speakers?
Sonically, the ear is happy :)
I build AJ as monoblocks in Modushop MonoBlock 4U 400 box. Attached photo with power supply.
 

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