re grounding:
this worked for me....
1. each power supply lead have its own ground return wire that goes to psu 0 volt point..
2. these form a twisted pair..
3. all 0 volt return wires are soldered to a single psu 0 volt point..
4. the PSU 0 volt point is connected to the chassis at only one spot... and sometimes you can not like when using plastic casings like i do..
5. i will not let the signal ground return wire ride on any psu ground return wire, i use a separate wire for that..
so to get to the bottom of this grounding issue is to start from the PSU ground..
this worked for me....
1. each power supply lead have its own ground return wire that goes to psu 0 volt point..
2. these form a twisted pair..
3. all 0 volt return wires are soldered to a single psu 0 volt point..
4. the PSU 0 volt point is connected to the chassis at only one spot... and sometimes you can not like when using plastic casings like i do..
5. i will not let the signal ground return wire ride on any psu ground return wire, i use a separate wire for that..
so to get to the bottom of this grounding issue is to start from the PSU ground..
Attachments
Last edited:
Thanks Ghzgary for the reference - lots to think about there. Agree with your point on grounding options, but those who did the initial design have a grounding scheme in mind and knowing that would be a good place to start.
TonyTecson thank for sharing. Do you consider any sort of RC network, NTC or AC bridge between your PSU 0 and chassis?
TonyTecson thank for sharing. Do you consider any sort of RC network, NTC or AC bridge between your PSU 0 and chassis?
Hi, everybody. I'm newcomer here. I'm very impressed by the Aleph's schematics. I want to build it myself. I have one question: does this amplifier need speaker protection? Original one does not have it. To my mind, if output transistor blow up, we will get a rail voltage on the amplifier's output. Am i wrong?
Every amplifier should have a protection for DC. Also, the Aleph J does have a turn-on and turn-off hump, which h will be less of an issue with a DC protection. I use XRKs SSR DC protection boards, which are great.
Aleph J powering a set of B&W DM604 S3
Hi
I am considering building the Aleph J amp available at the DIY Audio Store. I am not quite sure if this is the best amp for my speakers:
B&W DM604 S3 - 3-way vented-box system
Frequency range(-6 dB): 30Hz and 42Hz
Power: 200W into 8Ω
Sensitivity: 90dB spl (2.83V, 1m)
Impedance: 8Ω (minimum 3.0Ω)
Would this Aleph J be a good choice or is my speakers to hungry for SE amp?
All help is much appreciated 🙂
Hi
I am considering building the Aleph J amp available at the DIY Audio Store. I am not quite sure if this is the best amp for my speakers:
B&W DM604 S3 - 3-way vented-box system
Frequency range(-6 dB): 30Hz and 42Hz
Power: 200W into 8Ω
Sensitivity: 90dB spl (2.83V, 1m)
Impedance: 8Ω (minimum 3.0Ω)
Would this Aleph J be a good choice or is my speakers to hungry for SE amp?
All help is much appreciated 🙂
miklau -I have B&W 804D speakers which I used with a Krell KAV-400i, and a McIntosh MAC 6700. I thought that 200 W per channel was necessary for the past decades. I was also concerned about the 25W from the M2X and the Aleph J. The speakers have never sounded so great, both the M2X and the Aleph J drive the speakers with ease and I have yet to turn the volume past 12 oclock.
You will love how the Aleph J sounds with the B&W speakers.
You will love how the Aleph J sounds with the B&W speakers.
Thanks for your input elwood625 🙂
That is a very good comparison regarding sensitivity of the 2 speakers even through yours are miles better than my old DM604´s 😉
Did you build your Aleph/M2X with the recommend PSU and transformer specified in the build guide?
/Mikkel
That is a very good comparison regarding sensitivity of the 2 speakers even through yours are miles better than my old DM604´s 😉
Did you build your Aleph/M2X with the recommend PSU and transformer specified in the build guide?
/Mikkel
I used 600va transformers 18v secondaries from AnTek.
8 - 15,000uF caps on the M2X with two 10uF run caps, one on each rail.
8 - 22,000uF caps on the Aleph J.
Other than that, the PSU and amps are built according to the build guide. I did use a different cap for C1 on the Aleph J amp boards than the BOM.
8 - 15,000uF caps on the M2X with two 10uF run caps, one on each rail.
8 - 22,000uF caps on the Aleph J.
Other than that, the PSU and amps are built according to the build guide. I did use a different cap for C1 on the Aleph J amp boards than the BOM.
The J will easily drive your speakers. Each of the amps I have built (Aleph J, F4, F5, F6, M2 and BA3) drive my Harbeth C7ES-3 speakers, which have a 6 ohm impedance and 86db efficiency, without issue. Both the Pass Labs XP-10 and Conrad Johnson ET3SE preamps drive the J, 5, 6, M and BA3 to levels beyond comfort. The XP-10 is marginal with the F4 but the ET3SE drives it to levels beyond my listening comfort.
Just finish my Aleph J. I was able to do it from beginning to end without asking a single stupid question so that’s an accomplishment 
It was really easy to bias and do the offset..... compared to the F5 and also seems to run much hotter.
The transformer buzzes slightly but you can’t hear it with the lid on.
There is a very fain buzz coming from both speakers, but I have to really stick my ear into my speakers to hear it. I’m sure my OCD will get me tinkering around with fixing it but for now I’d rather just listen to some music.
Here are some pics - Aleph J Clone - Google Photos
It was really easy to bias and do the offset..... compared to the F5 and also seems to run much hotter.
The transformer buzzes slightly but you can’t hear it with the lid on.
There is a very fain buzz coming from both speakers, but I have to really stick my ear into my speakers to hear it. I’m sure my OCD will get me tinkering around with fixing it but for now I’d rather just listen to some music.
Here are some pics - Aleph J Clone - Google Photos
Attachments
Nice build.
Check the post# 4565; it explains how to get rid-off the buzz.
The left channel input wiring runs in parallel with mains wiring/terminal block. It may help if you position the input wiring close to the heatsink.
Check the post# 4565; it explains how to get rid-off the buzz.
The left channel input wiring runs in parallel with mains wiring/terminal block. It may help if you position the input wiring close to the heatsink.
Well done Mrshazbot.
Is the purple cable with the yellow termination the electrostatic shield from the transformer? I can't tell if it's connected. Shouldn't this be connected to your star ground?
ESP Transformers For Small Signal Audio, 1.0 - Transformer Basics (line starting 'CP-S is the inter-winding capacitance')
Is the purple cable with the yellow termination the electrostatic shield from the transformer? I can't tell if it's connected. Shouldn't this be connected to your star ground?
ESP Transformers For Small Signal Audio, 1.0 - Transformer Basics (line starting 'CP-S is the inter-winding capacitance')
Just finish my Aleph J. I was able to do it from beginning to end without asking a single stupid question so that’s an accomplishment
It was really easy to bias and do the offset..... compared to the F5 and also seems to run much hotter.
The transformer buzzes slightly but you can’t hear it with the lid on.
There is a very fain buzz coming from both speakers, but I have to really stick my ear into my speakers to hear it. I’m sure my OCD will get me tinkering around with fixing it but for now I’d rather just listen to some music.
Here are some pics - Aleph J Clone - Google Photos
Congratulations, Nice Build! The J is a great amp.
to Mrshazbot #4612
Hello Mrshazbot,
a very nice amp! Congrats.
Only one annotation:
your cables/wires run unprotected through the perforated metal sheet.
I think there are some sharp edges. Rubber grommets between the cables and metal would be great. 🙄
Only a thought!
Greets
Dirk 😉
Hello Mrshazbot,
a very nice amp! Congrats.
Only one annotation:
your cables/wires run unprotected through the perforated metal sheet.
I think there are some sharp edges. Rubber grommets between the cables and metal would be great. 🙄
Only a thought!
Greets
Dirk 😉
Attachments
Just finish my Aleph J. I was able to do it from beginning to end without asking a single stupid question so that’s an accomplishment
It was really easy to bias and do the offset..... compared to the F5 and also seems to run much hotter.
The transformer buzzes slightly but you can’t hear it with the lid on.
There is a very fain buzz coming from both speakers, but I have to really stick my ear into my speakers to hear it. I’m sure my OCD will get me tinkering around with fixing it but for now I’d rather just listen to some music.
Here are some pics - Aleph J Clone - Google Photos
Great Build Mrshazbot🙂
What size transformer did you use? I am trying to figure out if a 500va is "enough" or 600va would be better.
How did you wire your termistors? I am assuming this is to prevent having a Soft start module?
Have you used Clarity MKP as your input couplings caps?
/Mikkel
Agreed on the grommets... or at least drilling some bigger holes. That was my intention then I never did it and I need to go back and fix that. I also need to connect the SE inputs.
The purple wire got connected to the ground point also. I left it loose for curiosity, so I could connect and unconnected it to ground and see if it did something noticeable, which it didn’t.
The purple wire got connected to the ground point also. I left it loose for curiosity, so I could connect and unconnected it to ground and see if it did something noticeable, which it didn’t.
