About possible Babelfish J interest
pretty much covered , plenty on info in linked thread , so you can easily make change to any existing Aleph , or make your own even on veroboard or PtP
I know for several Alephs made PtP .......
pretty much covered , plenty on info in linked thread , so you can easily make change to any existing Aleph , or make your own even on veroboard or PtP
I know for several Alephs made PtP .......

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Pass DIY Addict
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The next thing to try is star grounding, but I'm not sure that's possible given your PSU configuration... ? I'd need to see a few more photos of the rig wired up.
After trying lots of things with my amp to eliminate the hum, I ended up installing a new CRC capacitor bank with a new set of caps. The hum now is gone, nothing but nice clean music now! 😀
At this point, I'm guessing that my original PSU had a bad cap or two in it that resulted from over heating when soldering to the 12g solid core wires that ran under my perfboard. I'll need to pull the old ones and test them one at a time.
I do appreciate everyone's time and suggestions, it was a useful process of elimination.
Hello,
My aleph J is finished and working, I am very happy, but I have one question :
On the picture attached does the CL60 thermistor is correctly positionned ? Is a capacitor in parallel necessary(like in the standard Pass PSU) ? It's because the amp make a big "pop" in the speakers when it is switched on or off.
Thank a lot for your responses.
My aleph J is finished and working, I am very happy, but I have one question :
On the picture attached does the CL60 thermistor is correctly positionned ? Is a capacitor in parallel necessary(like in the standard Pass PSU) ? It's because the amp make a big "pop" in the speakers when it is switched on or off.
Thank a lot for your responses.
Attachments
which thermistor ?
practically - you need to have 2 of them - one in series in xformer primary , second between audio GND and chassis , and chassis must be connected to safety GND
practically - you need to have 2 of them - one in series in xformer primary , second between audio GND and chassis , and chassis must be connected to safety GND
which thermistor ?
practically - you need to have 2 of them - one in series in xformer primary , second between audio GND and chassis , and chassis must be connected to safety GND
Thanks, so i'm good with it, on the right down in the picture, near the wires of the DNM, one CL60 is in serie the primary, and a second thermistor (on the left up of the picture, with yellow/green wires) between PSU ground and chassis, which is connected to the Ground.
as I see it - that NTC in terminal block (where probes are ) is connected on one terminal , practically nonexistent in circuit
you need to connect it inline - in series with one primary wire
besides that , ensure proper isolation/distance to chassis - way you did it is dangerous - it can touch chassis .....
you need to connect it inline - in series with one primary wire
besides that , ensure proper isolation/distance to chassis - way you did it is dangerous - it can touch chassis .....
Attachments
as I see it - that NTC in terminal block (where probes are ) is connected on one terminal , practically nonexistent in circuit
you need to connect it inline - in series with one primary wire
besides that , ensure proper isolation/distance to chassis - way you did it is dangerous - it can touch chassis .....
Ok, that's what I was thinking too, I will correct this wiring tomorrow.
Thanks a lot.
as I see it - that NTC in terminal block (where probes are ) is connected on one terminal , practically nonexistent in circuit
you need to connect it inline - in series with one primary wire
besides that , ensure proper isolation/distance to chassis - way you did it is dangerous - it can touch chassis .....
What benefit does this CL-60 in series with the primary wire brings when compared to the series with the ground? I see that almost all the builds use this thermistor in series with the ground->IEC earth rather than primary wire.
Thanks
two different places, two different roles
one in primary having role of soft start
one in between audio gnd and chassis is hum breaker
one in primary having role of soft start
one in between audio gnd and chassis is hum breaker
Ok got it, so if we are using a properly built soft start board then no need to use the thermistor in-line with primary right?
Thanks
Thanks
Hello,
after the modifications of cl60 thermistor, the amplifier is working, but I have a canal dead quiet, but the other have a weak buzz (of 50hz I think), as you see on the picture attached, it's the canal on the right, where the wires of AC (blue/violet) passed.
Can I put the AC Wire ((blue/violet) which goes to the red/red of the primary,) under the perfored steel plate to make a shield to avoid this buzz or it would be useless ?
Thanks.
after the modifications of cl60 thermistor, the amplifier is working, but I have a canal dead quiet, but the other have a weak buzz (of 50hz I think), as you see on the picture attached, it's the canal on the right, where the wires of AC (blue/violet) passed.
Can I put the AC Wire ((blue/violet) which goes to the red/red of the primary,) under the perfored steel plate to make a shield to avoid this buzz or it would be useless ?
Thanks.
Attachments
Can I put the AC Wire ... under the performed steel plate to make a shield to avoid this buzz... ?
ofcourse you can ; but this would be best after doing the proper wiring arrangement as suggested by Zen.
it is even highly advisable to have all the harneses behind a steel shield; i do not know why everyone exposes his/hers wires 😀
I have a 400va Antek in my Aleph J and have a CLC power supply with 25kuf 10mh 47kuf filter. I did not use any surge limiting. The amp powers up without any noises from the transformer and it runs quiet. I recommend the 400va Anteks. They are not expensive but perform well with no mechanical hum in the configuration I am using. I have the 20v version and I bias a little hotter than spec. Idle power consumption from the line is 270w so the trans runs quite warm.
So you may not need the cl60 surge suppressor at all. I also run with the audio ground connected directly to the chassis without any hum issues.
So you may not need the cl60 surge suppressor at all. I also run with the audio ground connected directly to the chassis without any hum issues.
You might get away with not using a surge limiter , but I did not. I built four F5 mono blocks all tied to a common power strip which I used to turn them on, and constantly tripped a dedacated 20 amp house breaker. I installed the CL60's on each amplifier and have not had a problem since
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