It was under a no-load situation, 60v x 1.414, but is nearly the same under load which shows an adequate Current supply. Line voltage is 118 to 120 volts AC, I have a line voltage monitor on the sound room power. I also have 25mvdc on the AC lines so I have DC blockers on the power amps.
I wasn't able to find slightly lower voltage stock transformers so I went to 100vdc caps on the positive side and will try 68v, and then 62v zeners if necessary.
I wasn't able to find slightly lower voltage stock transformers so I went to 100vdc caps on the positive side and will try 68v, and then 62v zeners if necessary.
Received parts yesterday, updated the caps on the positive side to 100 volts and put in the 10k 1w bleeder resistors and put in a 68 volt zener on the positive voltage.
The positive rail voltage stabilized at 73.6 volts, unload close enough I guess. The bleeder on the positive side runs warm and is dissipating about 1/2 watt, .007ma, and it bleeds down slowly but at an acceptable rate. So, on to hooking up the preamp modules, testing and listening. If I like the sound of the X-SOBOZ sounds better than the Aleph-P modules than I will have to redo my preamp with the Power Supplies in a separate chassis.
The positive rail voltage stabilized at 73.6 volts, unload close enough I guess. The bleeder on the positive side runs warm and is dissipating about 1/2 watt, .007ma, and it bleeds down slowly but at an acceptable rate. So, on to hooking up the preamp modules, testing and listening. If I like the sound of the X-SOBOZ sounds better than the Aleph-P modules than I will have to redo my preamp with the Power Supplies in a separate chassis.
John,
Got my PS boards, put a couple of sets together and they worked well. I found the small dots for negative on the Zener's and positive on the electrolytic's to be a bit confusing at first but I suspect you were limited by the parts library of your CAD software. It's a simple circuit so it wasn't that difficult to figure it out.
I found the best value to use for the Zener's was 24V. I can easily measure them with my 35V power supply so I could put together accurate strings for all positions. I purchased thirty for the two boards and measured them all. They were all in a range 24.20 to 24.70. Out of that set I was able to get -20.1V and strings of +70.1 -70.3 output into load when powered up. I was seeing 90V at the 610 drains.
Regards,
Roy
Got my PS boards, put a couple of sets together and they worked well. I found the small dots for negative on the Zener's and positive on the electrolytic's to be a bit confusing at first but I suspect you were limited by the parts library of your CAD software. It's a simple circuit so it wasn't that difficult to figure it out.
I found the best value to use for the Zener's was 24V. I can easily measure them with my 35V power supply so I could put together accurate strings for all positions. I purchased thirty for the two boards and measured them all. They were all in a range 24.20 to 24.70. Out of that set I was able to get -20.1V and strings of +70.1 -70.3 output into load when powered up. I was seeing 90V at the 610 drains.
Regards,
Roy
Found some time today to do some listening tests between the X-BOSOZ preamp modules and the Aleph P preamp modules.
I found the X-BOSOZ to be very quiet for background noise and sounded very good but the Aleph P was a bit more transparent, more detailed.
Each was using their own power supply but I am going to try using the BOSOZ power supply with the Aleph P boards. It will require a zener change for +60 volts and won't need the negative side. Just something to try and see what I hear.
I found the X-BOSOZ to be very quiet for background noise and sounded very good but the Aleph P was a bit more transparent, more detailed.
Each was using their own power supply but I am going to try using the BOSOZ power supply with the Aleph P boards. It will require a zener change for +60 volts and won't need the negative side. Just something to try and see what I hear.
I would like to ask some advise / help with the regulated power supply.
Would like to use it with my Kaneda Pre-amp which required +/- 35V rail voltage.
Way back I made some home brew PC boards for this purpose, you can see the pictures. Unfortunately I forget how I set up the required rail voltage, I know I have to pick the correct value Zener diodes but I am not sure how to calculate the total value to get 36VDC rail voltage. I can use 2X30VAC power transformer, I have at home. Would you be so kind to help me with this set up. Otherwise this stuffed boards will be total useless ans same time I will have to order something (maybe much worst quality) from eBay. This is a well designed lovely PS.
Thank you very much!
Greetings gabor
Would like to use it with my Kaneda Pre-amp which required +/- 35V rail voltage.
Way back I made some home brew PC boards for this purpose, you can see the pictures. Unfortunately I forget how I set up the required rail voltage, I know I have to pick the correct value Zener diodes but I am not sure how to calculate the total value to get 36VDC rail voltage. I can use 2X30VAC power transformer, I have at home. Would you be so kind to help me with this set up. Otherwise this stuffed boards will be total useless ans same time I will have to order something (maybe much worst quality) from eBay. This is a well designed lovely PS.
Thank you very much!
Greetings gabor
Attachments
The original Pass Aleph Power Supply used 7 9.1 Zeners in series to obtain a 60v + regulated voltage. For my Aleph P preamp that I copied from my original to experiment with, I ended up using the BOSOZ power supply with one 62v zener, found it to be quieter with one zener than a string of them but since you have a bunch of zeners you can experiment with different combinations until you have the voltage you want.
Thank you. I will start with 2x9.1 V and 2x12 V type, let see. It is a great information one zener is quieter than multiple. I can order what ever I need ones I have some idea what I need. Also I have 35VAC transformer if the 30 will be not enough because voltage loss on the regulation.