Aleph-X diff pair trouble?

jeekee · 28th July 2012, 12:15 PM

Hi all,

I've build an Aleph-X and am having some trouble with one side (using rev. 1.0 board, low power Grey's design, options: D1a, J1a, jumper on Q12a, r48 and r49). The voltage over r25 seems ok (around 4V) while over r23 its over 6V. I've already changed the diff pair but to no avail. Also I noticed that R1-4 and R42-45 are heating up excessively.

Any ideas what could be the problem here?

Kind regards.

Zen Mod · 28th July 2012, 01:24 PM

some of us aren't so informed about exact pcbs and schm version

fill that blanks (schm , pcb graphic info , pics of your exact work) here and maybe someone will be able to help

jeekee · 30th July 2012, 04:19 PM

Late night build and post is a recipe for disaster. I've checked wiring 20 or so times and final it bit me in the ***, swapped the gate and source of one of the output MOSFET's... fixed it and voila: SOUND

Thanks for the post anyways!

28th July 2012, 12:15 PM	#1
jeekee diyAudio Member Join Date: Jun 2012	Aleph-X diff pair trouble? Hi all, I've build an Aleph-X and am having some trouble with one side (using rev. 1.0 board, low power Grey's design, options: D1a, J1a, jumper on Q12a, r48 and r49). The voltage over r25 seems ok (around 4V) while over r23 its over 6V. I've already changed the diff pair but to no avail. Also I noticed that R1-4 and R42-45 are heating up excessively. Any ideas what could be the problem here? Kind regards.

28th July 2012, 01:24 PM	#2
Zen Mod diyAudio Member Join Date: Jan 2003 Location: ancient Batsch , behind Iron Curtain	some of us aren't so informed about exact pcbs and schm version fill that blanks (schm , pcb graphic info , pics of your exact work) here and maybe someone will be able to help __________________ my Papa is smarter than your Nelson ! tnx to clean thread ; Cook Book ; PSM LS Cook Book ; Baby Diyaudio FORUM ; Mighty ZM's Bloggg;I'm dumb

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30th July 2012, 04:19 PM	#3
jeekee diyAudio Member Join Date: Jun 2012	Late night build and post is a recipe for disaster. I've checked wiring 20 or so times and final it bit me in the ***, swapped the gate and source of one of the output MOSFET's... fixed it and voila: SOUND Thanks for the post anyways!