I use a Benchmark LA4 preamp which has both SE and XLR inputs.
Do you think there is any advantage to use a high quality output transformer such as the Jensen JT-11-BMCF to utilize the XLR input or use the SE output directly?
Only advantage in this case, if it isn't about a hostile noise environment and a long cable run, its the associated signal boost when converting SE to balanced actively or with a transformer.
Use the SE output directly if your system gain is enough. You could also try the SE to XLRM Benchmark Studiostage adapter cable I believe. Useful if the LA4 offers more gain via its balanced inputs.
Use the SE output directly if your system gain is enough. You could also try the SE to XLRM Benchmark Studiostage adapter cable I believe. Useful if the LA4 offers more gain via its balanced inputs.
Thanks for reply! This PCB is only for personal use. Helion Audio is just me, and I sell nothing 
I used this name (Helion) 30 years ago when I worked as a consultant for some years, and I needed a "company" name. Today I use Helion Audio for fun, just pretending. It does not exist outside of my imagination....
I see that 2SK146 is not comparable to 2SK170, but electrically, could it be used? By adjusting drain current, maybe?
Sorry for my untimely questions but hope you have some pointers!
I used this name (Helion) 30 years ago when I worked as a consultant for some years, and I needed a "company" name. Today I use Helion Audio for fun, just pretending. It does not exist outside of my imagination....I see that 2SK146 is not comparable to 2SK170, but electrically, could it be used? By adjusting drain current, maybe?
Sorry for my untimely questions but hope you have some pointers!
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Alright then, thanks for explaining Helion Audio. No it can't substitute the 2SK170 in the phono because its not only a matter of Ibias readjustment. There are also RIAA EQ filter alignment and bandwidth narrowing issues from its much higher Miller effect in the second stage. You can pull out individual TO-92 from a dual dif pair 2SK146 case to effectively have two matched 2SK147 and use them for Q1 Q2. For 2SK170 you may get some LSK170B from the store or Tea-Bag may help you on that but I don't know for sure.
Thanks a lot! One last question: Is C3 just a coupling capacitor, or does it also play a part in the RIAA or maybe rumble filter? I wonder because I have caps of sufficient quality with higher values, but not 100nF.
Thx! I eventually came across postings where C3 was discussed. Guess I go for 100nF
Anyway, my UFSP is going to be a "use what I got" project. So please be kind! This is current status of the board;
2SK369 -> 2SK146
FP5102 -> 2SK117
BC327/40 -> BC556C
The additional green LED and BD241A belongs to an on-board cap multiplier.
Some classic Japanese PLL like yours are timeless in looks and operation. I had briefly listened to a Denon DP-47F automatic turntable a week ago. It had a Denon DL-160 HMC mounted and it was playing surprisingly good for its unispiring to firstly look at short length tonearm. The automation itself stayed impressively accurate after all these years.
Just finished my Ultra FSP... I prefer compact sized chassis so went with this custom 10.5" x 8" x 2" from Par-Metal which fits perfectly.
The PSU is in a modushop Galaxy 2U chassis. Single Hammond 1182K30, which is dual 30VAC 80VA transformer.
I didn't use coax wire on the input because it was so short, after exposing both ends there is barely any wire left shielded.
I went with the recommended Mundorf SGO and Clarity Cap MR, and R1 & R17 Charcroft Z-foil's
Set up for MM cartridge, T.P. is rock solid on 4V. B+ is 31V DC and Raw DC is 42V DC.
My Technics SL-1200G has a fault and is out for repair under warranty so I am temporarily using a Thorens TD-309 with Grado Gold 3 cart.
Now need to do some listening ....
The PSU is in a modushop Galaxy 2U chassis. Single Hammond 1182K30, which is dual 30VAC 80VA transformer.
I didn't use coax wire on the input because it was so short, after exposing both ends there is barely any wire left shielded.
I went with the recommended Mundorf SGO and Clarity Cap MR, and R1 & R17 Charcroft Z-foil's
Set up for MM cartridge, T.P. is rock solid on 4V. B+ is 31V DC and Raw DC is 42V DC.
My Technics SL-1200G has a fault and is out for repair under warranty so I am temporarily using a Thorens TD-309 with Grado Gold 3 cart.
Now need to do some listening ....
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Thanks for the kind words! I've been swapping carts around and haven't settled on any yet. Currently have AT VM540ML, Goldring 1042 and AT OC9-XEN. I had the OC9-XSL for a while and it is noticeably better than the XEN but the resonant frequency is on the low side and I'm trying to find a cart that lands in a more optimal 8-9Hz zone.
Out of these three I might prefer the VM540ML which tracks great and has a very lively sound.
If I try a higher end MC I will try Goldring Ethos or ART9-XA which should be very compatible with the Technics tonearm.
Out of these three I might prefer the VM540ML which tracks great and has a very lively sound.
If I try a higher end MC I will try Goldring Ethos or ART9-XA which should be very compatible with the Technics tonearm.
Technically the Ethos should have the higher dynamic range sound since it has healthier 0.5mV output at 4Ω source resistance vs the 0.2mV at 12Ω ART9-XA. More adept in driving the MC phono mode better and all that. Loading experimentation can also go very low to 58Ω in steps with the typical Rx resistors values by paralleling ON combinations. There's an S1-S4 chart in the schematics post.