I tried searching this thread but didn't find the answer.
I have the FSP boards and would like to use it for my MM Shure M97xE. Turntable is nothing fancy either, just want to have a decent phono amp to spin my old vinyls
which are collecting dust and static ...
I have quite a bit of 2SK170V and 2SK170BL and would like to use them instead of the 2SK369. Some previous posts suggested this could be done. If so, what parts I need to adjust to?
FWIW, the Shure manual is in
http://cdn.shure.com/user_guide/upload/1070/us_pro_m97xe_ug.pdf
Thanks!!
I have the FSP boards and would like to use it for my MM Shure M97xE. Turntable is nothing fancy either, just want to have a decent phono amp to spin my old vinyls
which are collecting dust and static ...
I have quite a bit of 2SK170V and 2SK170BL and would like to use them instead of the 2SK369. Some previous posts suggested this could be done. If so, what parts I need to adjust to?
FWIW, the Shure manual is in
http://cdn.shure.com/user_guide/upload/1070/us_pro_m97xe_ug.pdf
Thanks!!
Hi Salas and Merlin,
i think i was one of the very first to build the Folded Version and
later on i bought the PCB (was it from TeaBag?) and i´m still very
happy with this PhonoPre. At the moment i just need an MCHeadamp
for another Project and will try the Folded MC Pre … well, it´s just in
time ;-)
Just two (or three) questions:
1. (according to Merlin) which PSU for the MC PrePre? (the smaller the better)
2. which ´lytics for the 470uF ? Still silmic II ? What about those small high tec
low esr polymer ones?
3. that IDSS to prefer for the 2sk170bl?
cheers and thanks
Ulf
i think i was one of the very first to build the Folded Version and
later on i bought the PCB (was it from TeaBag?) and i´m still very
happy with this PhonoPre. At the moment i just need an MCHeadamp
for another Project and will try the Folded MC Pre … well, it´s just in
time ;-)
Just two (or three) questions:
1. (according to Merlin) which PSU for the MC PrePre? (the smaller the better)
2. which ´lytics for the 470uF ? Still silmic II ? What about those small high tec
low esr polymer ones?
3. that IDSS to prefer for the 2sk170bl?
cheers and thanks
Ulf
Hi there,
I got that info, but I want to use 2SK170 (either V or BL) instead of 2SK369BL. Since the transconductance of the 2SK170 isn't as high as the 2SK369, I wonder what needs to be adjusted to use, let say, the 2SK170V.
Thanks,
The 369BL has superior Yfs at comparable Id and less noise, both total and GR noise. If you have to use 2SK170V in the Pre-Pre, to near Yfs 55 of an 11mA Idss 369 will ask for 20mA Idss K170V. That's borderline V. You need to pick some more likely occuring matching V and then let me know so to give you resistor values because there is a balance there between Id current consumed and the rest going where on what load for how much Yfs for a given gain. Voltage source V1 can be a simple capacitance multiplier after an LM317.
Hi Ulf, I remember.
happy to know it still serves you OK. 
For V1 PSU read my post above
Any renowned quality lytic you fancy
The more Idss you can match from your K170 stash and then let me know to give you personal key resistor values or V1 value change
You may choose Idss as recommended for 369 in the manual but that will bring a gain loss vs original FSP spec. If the gain in your system will be less than enough for good volume let me know so we will discuss few resistor changes around the type and Idss you substituted in order to recover some gain. I would still recommend you get a 369BL pair that will keep you on spec plus they may come handy for a by the book high MC model upgrade in the future. Its good to have them before inevitably never finding again.
Thanks, Salas.
I have to admit that it is not likely that I will go for a MC cart even though never say never I just measured 50 SK170V's, quite a few are in the 12ma range. I will build the FSP with the 2SK170V and to see how it will go. Too many of these and need to find a way to use them
I have to admit that it is not likely that I will go for a MC cart even though never say never
I just measured 50 SK170V's, quite a few are in the 12ma range. I will build the FSP with the 2SK170V and to see how it will go. Too many of these and need to find a way to use them I ended with a 15nF 1% + 300pF in the RIAA.
And wait for better LC Meter to remeasure and choose the final riaa filter cap.
Considering the teflon coupling cap (100nF) , no harsness anymore and sound has weight now. I just have to find the right balance for me.
I don't know if it's burnin', time settle down, treble curve correction but i think one should consider teflon cap sound after a little time. it's really worth it. It provides detailed,airy and neutral sound with bass correponding i think to the recording (from really deep to shy one). Not a cap on the warmer side but really interesting.
If other has has tried, very interested in feedback I am
I don't think FSP PCBs are around right now. But I will give signal for a next general GB soon because the Ref-D mini size reg version is ready and tested, its DC Flexy companion raw power board that can take four pole or two pole reservoir capacitor is ready and tested, the Input Selector module with up to six inputs and volume for general use and for complementing my new line preamp/headphone preamp with gain DCG-3 is ready and tested, delays made the PCB for the preamp itself just finishing off its proto design CAD stage though. But there are very successful matrix board builds running for months now.
Sounds like a perfect "next winter project" I don't do anything during summertime. Too hot in the mancave
This year I only finish the Ovation NX amp. Your RIAA came between that one.... But then it's over for this year. Well, exept for installing clean power in my house... but that's it. (I think)
I don't do anything during summertime. Too hot in the mancave This year I only finish the Ovation NX amp. Your RIAA came between that one.... But then it's over for this year. Well, exept for installing clean power in my house... but that's it.
(I think)