It was this picture that caught my attention:
https://www.diyaudio.com/forums/att...42-aleph-illustrated-build-guide-img_1531-jpg
On the right channel PS board it appears to me that at the PS board output (left side of board), the two sides of ground are not tied together. The three solder pads with wire holes are empty and not soldered, and there are individual positive and negative rail ground wires connecting to the amplifier boards.
Edit:
It looks like the capacitors are blocking the view of the wire connecting the two grounds at the PS board output. Looking extra hard I think I see a bit of solder. In that case you do have the two sides of ground connected at the board output - my mistake for not seeing that.
For a more robust connection of the two sides of ground the three unused pads can also be used to tie the two sides together.
Those unused pads are actually a better place to connect the ground to the amplifier board, speaker, and to the chassis. It is better for grounding if the ground connection to the capacitors of a dual rail supply is located equally between the positive and negative rail grounds.
Thank you very much for looking. You're correct, the jumper is there. I like the idea of beefing it up a bit. It can't hurt. Next time it's out of the case, I can add a jumper or two. I use the Euroblocks for the connection points b/c I take the amp boards in and out. I know they may not be as solid a connection as directly soldering to the board, but it makes my life a whole lot easier than desoldering / soldering each time I want to swap out amp boards.
Again, thanks for taking the time to explain and taking a good look at the boards!
All components have been tested and selected before installation.
What changes have occurred in the sound with double mono?I got the Aleph J updated to dual-mono.
Have you ever wanted to replace the electrolytic capacitors in the filter of the amplifier power supply? This should give an increase in quality.
Nobody wants to speak of this anymore
apparently is a tale of a mule that was gravely abused in the past ... conclusions remain ofcourse in the realm of sociology so nothing to be worried about .
Thanks for the response ;
I prepared a while back and again recently a cheap solution for eliminating any imaginated results:
Geekcreit(R) 5V 4 Channel Relay Module For Arduino PIC ARM DSP AVR MSP430 Blue - US$2.49
(i can quicly draw a schematic for the setup if needed)
use a 2 way rocker switch with a long wire in the listening position
quickly align both amplifiers volumes using: Online Tone Generator - generate pure tones of any frequency and a microphone... any microphone.
with this ... any amplifier / speaker(s) can be tested side by side and expressions like "bigger sound" or "wider sound stage" that actually mean missing or parasitic audio information in the freq range the stereo effect resides will be very quickly confirmed /unconfirmed by pressing a button.
Otherwise ; if any pause in switching sources or any level difference exists, the processor in the brain will kick in, add bias and the comparison will become like any youtube review of any device ... " eye opening " " bigger sound "or any dumbo jumbo thought of when in reality there is no or less than marginal sound differences between compared sources. (see wire or coupling capacitors reviews, where diy'ers fall like flies in the expense trap)
You didn’t mean Mr. PassNobody wants to speak of this anymore
https://www.passlabs.com/amplifier/xa60.8
Thanks, Zen Mod. I chose 2N5551 (for ZTX450) and 2N5401 (for ZTX550) because they are pin-for-pin compatible.
Question: Q4 serves the CSS AC gain duties. With that in mind, is the hfe value of that transistor important?
Nobody wants to speak of this anymore
I did wrote about that , but can't remember where
Dual mono would allow for very short wiring between transformer->bridge rectifier->power supply->PCB. Half compared to a single power supply wiring length.
2 X 400VA transformers and a proper full-blown 2 X power supply capacitor banks. Later on, if it turns out that one is enough (listening test), you have a power supply complement for an M2x...
2 X 400VA transformers and a proper full-blown 2 X power supply capacitor banks. Later on, if it turns out that one is enough (listening test), you have a power supply complement for an M2x...
But mr ontool, the mule is a metaphor used a bit back impersonating the mono block and separate power supply approach.You didn’t mean Mr. Pass
And yes the jewel attached brings tears to anyone's eyes in search of perfect audio signal reproduction and engineering beauty.
He made the power completely separately for each channel, as implemented in a monoblock.
Just sorted out which components i need to order especialy for the PSU part.
It will be CRC with a bleeder in dual mono config.
C-C-R-C-C (each rail)
So i was thinking to use 16x 47mF low esr C's but i think it's overkill, what do you think? C-C-R-C or C-R-C ?
It will be CRC with a bleeder in dual mono config.
C-C-R-C-C (each rail)
So i was thinking to use 16x 47mF low esr C's but i think it's overkill, what do you think? C-C-R-C or C-R-C ?
Factory versions had what, 8 x 15mF?
While one must leave the term "overkill" at the door when entering here, 16 x 47mF is nevertheless a lot.
If you already have the 47s then 8 x 47mF would go down nicely (C-R-C); otherwise 16 x 22mF would also give a big bump over factory spec.
Cheers,
Jeff.
PS: careful of the inrush and transformer loading with that much capacitance
While one must leave the term "overkill" at the door when entering here, 16 x 47mF is nevertheless a lot.
If you already have the 47s then 8 x 47mF would go down nicely (C-R-C); otherwise 16 x 22mF would also give a big bump over factory spec.
Cheers,
Jeff.
PS: careful of the inrush and transformer loading with that much capacitance
Yeah, 47mF is a big enough capacitor that it is starting to go inductive at the upper frequencies of interest for an audio power supply. For bulk capacitance on each rail, a simple C-R-C configuration will be plenty. You could also try a C-R-C-R-C configuration with the first C at 33mF, and the next two at 27mF. That's what I have in my Aleph J.
My recommendation, which falls in the general category of Coloring Outside the Lines, is to add some high quality 1000uF or 2200uF caps at the first C and the last C in each rail. I tried this recently, and it improved the openness and finer detail of acoustic instruments in my AJ. Go ahead and let the basic PSU break in for at least 20 hours, then try adding the smaller caps. Let your ears be the judge.
My recommendation, which falls in the general category of Coloring Outside the Lines, is to add some high quality 1000uF or 2200uF caps at the first C and the last C in each rail. I tried this recently, and it improved the openness and finer detail of acoustic instruments in my AJ. Go ahead and let the basic PSU break in for at least 20 hours, then try adding the smaller caps. Let your ears be the judge.