He could try load the test PSU at 100mA with a circa 500 Ohm power resistor and see if its only due to regulation. He tested on 10mA already.
If so is the case it will come to normal when feeding the reg. If not so, he will still have to consider RC for cutting down any then confirmed excess.
Post #10607 has a member's picture of 30VA 36VAC labeled transformers resulting to 48VDC though. That is just on 10mA load by the standard bleeders. Between manufacturers...go figure.
OK, tried a few resistors in series (should have said I have 4 caps in parallel, i.e. 3 x 1500uF, Nichicon PS and 1 x 2,200uF, Nichicon KG), got to use what's already in the bits box 
Anyway ended up with RCRCRCRC, i.e. 10r-0r22-0r47-0r47.
This combination gives me 56vdc on no load and 49vdc with a 470k dummy load (in addition to the 2x 10k already fitted). Is this OK?
Thanks for the advise/help.
Anyway ended up with RCRCRCRC, i.e. 10r-0r22-0r47-0r47.
This combination gives me 56vdc on no load and 49vdc with a 470k dummy load (in addition to the 2x 10k already fitted). Is this OK?
Thanks for the advise/help.
OK, tried a few resistors in series (should have said I have 4 caps in parallel, i.e. 3 x 1500uF, Nichicon PS and 1 x 2,200uF, Nichicon KG), got to use what's already in the bits box
Anyway ended up with RCRCRCRC, i.e. 10r-0r22-0r47-0r47.
This combination gives me 56vdc on no load and 49vdc with a 470k dummy load (in addition to the 2x 10k already fitted). Is this OK?
Thanks for the advise/help.
oops! meant 470r, thanks for the help
and the spanner for the extra heat sinking and it gets hot too.
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The source is a Linn Sondek LP12, Linn Ittok LVII tonearm (Black) and Linn Troika MC cartridge (retipped by Sound-Smith USA with Ruby Cantilever and Nude Contact Diamond).
The LP12 has been rebuilt from my original Afromosia LP12 bought in the 80’s and now has a Black Ash corner braced plinth, Trampolin2, Cetech carbon fibre sub-chassis and powered from a Linn Lingo Mk1 . Also fitted is a Naim PreFix (slightly modified for more gain).
My preamp/s is a PFM Starfish and/or a PFM B4 buffer into an Avondale Audio NCC200 dual mono power amp, all driving a pair of B&W 804 Matrix (Rosewood) floor standing speakers.
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OK, after a hard days work finished everything, put in a box and adjusted it as per the guide. I used 2 2sk369 in front.
I matched and measured everything at the best of my abilities, even curve traced all the semis.
Also as many of you remember I was using the first prototype of the folded cascode, and put it in the same box with the same PS.
I didn' t expect much difference, but was pleasantly surprised. Almost every aspect of the sound was better. More defined bass, soundstage that was expanded in all directions and even more resolution. Noise was lower also.
Very happy! Thanks Salas!
I matched and measured everything at the best of my abilities, even curve traced all the semis.
Also as many of you remember I was using the first prototype of the folded cascode, and put it in the same box with the same PS.
I didn' t expect much difference, but was pleasantly surprised. Almost every aspect of the sound was better. More defined bass, soundstage that was expanded in all directions and even more resolution. Noise was lower also.
Very happy! Thanks Salas!
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I will build a second after I have fully tested and adjusted the Jfet riaa pre-pre's , at present adjusting the first one and all looking good (obviously one at a time)
OK, after a hard days work finished everything, put in a box and adjusted it as per the guide. I used 2 2sk369 in front.
I matched and measured everything at the best of my abilities, even curve traced all the semis.
Also as many of you remember I was using the first prototype of the folded cascode, and put it in the same box with the same PS.
I didn' t expect much difference, but was pleasantly surprised. Almost every aspect of the sound was better. More defined bass, soundstage that was expanded in all directions and even more resolution. Noise was lower also.
Very happy! Thanks Salas!
Very nice George. This one not only has more gain but also few better passives, thorough matches, not to forget the integrated regs sans cabling, economical double layer layout, multiple star grounds and guards benefits. You are the second early builder stating its a sure step above a previous p2p folded own build. Chuffed to know that all the painstaking attention to the board design details, the slight reg tunings, and general planning payed in the end not to my judgement only. Enjoy your build. Thanks once again for your help during the initial folded evaluations by lending your time and system for the conceptual p2p test we did almost a year ago.
I will build a second after I have fully tested and adjusted the Jfet riaa pre-pre's , at present adjusting the first one and all looking good (obviously one at a time)
Sounds like a plan. Is Starfish the Naim derived(?) stuff you guys do on pink fish media by the way?
OK, after a hard days work finished everything, put in a box and adjusted it as per the guide. I used 2 2sk369 in front.
I matched and measured everything at the best of my abilities, even curve traced all the semis.
Also as many of you remember I was using the first prototype of the folded cascode, and put it in the same box with the same PS.
I didn' t expect much difference, but was pleasantly surprised. Almost every aspect of the sound was better. More defined bass, soundstage that was expanded in all directions and even more resolution. Noise was lower also.
Very happy! Thanks Salas!
Very nice indeed.
Please let us know what where your cap choices and particularly the output cap.... Most important info for some of us
oops! meant 470r, thanks for the help
and the spanner for the extra heat sinking and it gets hot too.
Very cool clean build... envy your passive leg bending
OK, after a hard days work finished everything, put in a box and adjusted it as per the guide. I used 2 2sk369 in front.
I matched and measured everything at the best of my abilities, even curve traced all the semis.
Also as many of you remember I was using the first prototype of the folded cascode, and put it in the same box with the same PS.
I didn' t expect much difference, but was pleasantly surprised. Almost every aspect of the sound was better. More defined bass, soundstage that was expanded in all directions and even more resolution. Noise was lower also.
Very happy! Thanks Salas!
Lovely build there George. Is it a good idea to have those large caps from umbilical cord to feed the regulator?.
Quan
Very nice indeed.
Please let us know what where your cap choices and particularly the output cap.... Most important info for some of us
Output cap is Mundorf silver oil 3,3 uF. Interstage texas teflon .047uf.
Well, the idea is to have the caps near the regulator in order to form a small RC with the umbilical. In the PS box I have 15R after the diode bridge, 4700uf, 10h 200mA choke, Rcore transformers, all dual mono.