Simplistic NJFET RIAA

Thank You for Your information, Salas.
That is what I was thinking about... but these 2SK146 old beasts matched pairs in a single thermal capsule shows a very low noise for a JFET, maybe one of the quieter semiconductor devices ever made...
I am not a spice modeling user, however I believe that a simulator is in order to validate a SE design using these 2SK146 devices... I will report back.
 
Hopefully the public library is closed so

Litle update from me

I got the Simplistic working wit the reflektor and LM317
Tanks Joao litle caps work and on my list of things to do is have a play with type and values (got 100n MKS at the momement)

IT does sound realy good as I even managed to ge rid of the hum (one to many ground vires)

On the Reflektor I had a dogy plastic washer on one of the Mosfets and could not spot that with case open and ground floating so that sorted after a few hours and about 5p worth of new washer.

Sound wise I am realy happy I can still ear the pre Echo on the over mudulated late (nothing to do with tapes) copy of Bonaparte Retreat.

And I have been pushing the F5 with the volume pot as far as it could go.

Have a treat.
Pavlov's Dog - Julia (HQ) - YouTube

I am going to keep it as it is for a couple off weecks
Then rig up the bateries again and have a listen to the 2 versions back to back.

PS I got the 24 V version at the moment with prepre for MC (litle transistor and 4 2SK170) as I still intend to give bateries a fair chance.

After that I most definetley will go for the proper spec version that I am shure will sound even better.
 
diyAudio Chief Moderator
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Ah, the Pavlov's Dog...ringing a bell will make him drool. Moving Missuri vibrato, preferred Song Dance and Late November in that album...

Congrats on your progress. Now you get the benefit of a proper supply as the phono was early married with. The simplistic regs got first developed to support the phono as a matter of fact, to keep the record that is.
 
I use to play that a lot in may radio station in the late 70 I just wish my ears where the same and that I still had the PD25.

When I moved I left behaind quite a few records and finaly found this in one of the local second hand shops.

I supose that now with intraweb and such it shuld be easy enough to get a copy.

I have the CD myself (not getting in to sampling frequency argument) and I do not understand why it sound so much more copressed and lifless with killed off dinamics.
I rather listen to the scratchess.

I will post full SCH and pictures soon

Output cap ? does it have one?

Vref (if is the same one I am thinking about) 1mU pana FM

Operating current is 80 mA for 2 channels Simplistic (will have to remake pcb for second chanell reflektor after much component swapping)
 
diyAudio Chief Moderator
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He means the small value plastic capacitor in the RC network across the Reflektor's output.
''Vref cap'' Yes, he means the 1000uF one.
CCS current is governed by Vbe/R1 and you may crank it up to 200 or 300mA if your sinks still feel comfortable, its beneficial in that it lowers the reg's impedance. From that juice, only about 40mA tops goes to each phono channel. The rest burns to satisfy the sonic gods. Catchy name for a band btw, isn't it?:D
 
Hi there
Small cap is a 1 u MKS

I believe that MKS series does not sound that good and I am planning to change that to a better one.

Tanks for tip on R1 I do understand that increasing current improves on sound.

Also interesting that the dissipation current consumption can be lower which may be a bonus for battery operation.

Sinks should be ok as I am using a Pesante dissipante HI Fi 2000 (got 2 when I built the PSU for My F5)

I am going to draw proper SCH of both Reflektor and Simplistic and post later
for now get the picture.

Treat of the day
http://www.youtube.com/watch?v=Be7JBCFxd7k&feature=related

WE did a gig and run out of Juice the only thing running was the Dry ICE as we used the hot water from the transit for it.
The rest turned in to an acoustic section.
The first Album is prety good sound wise
 

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diyAudio Chief Moderator
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Goth on Friday the 13th...most suitable.:D

Yes extra current can be a sonic bonus in such regs since it lowers their impedance as I mentioned. Still they can run at max load demand+20mA as minimum when consumption is an issue. 1uF MKP could be different indeed. That capacitor is influential and there is scope for experimentation.
 
Tanks Salas

I am going to change that straight away.

I have been revising the SCH compared to the boards and reading a bit more about the circuit development.

I have IRF 610 (one of fw bits I have in stock at present) I read samwhere that it is bad choice and I am going to replace that as well.

The proper 640 is on its way