Simplistic NJFET RIAA

Have you tried to use small caps, ~ 0.1µF, soldering direct to the pins of the LM317 (from input and output to ground)? This should avoid oscillation.


No I have not tried that but I got a couple of circuits I am working on.

As I said at the begining of my adventure with Simplistic this is a realy good way to learn things (which is what interest me) so I will give the small capacitors a try and for this I tank you.

I got a board ready for Gyrator folowed by 317 and I will put the caps there and see.
 
I will need to do back to back listening which, as you ask I feel is the least I can do after all your help.

Fortunatley with new job I am now working 12 hours shifts 4 on 4 off so soon I will get plenty more spare time to try things out. (main reason why I have changed jobs but do not tell her please)
 
No hassle at all I think is actualy a realy good question.

I did not get a chance to listen to the 2 back to back due to the fact that once started I just could not stop putting just one more record on the spinner.

That just one more folowed by just one more folowed.... What beter indication of how good the Simplistic is?
 
No I have not tried that but I got a couple of circuits I am working on.

As I said at the begining of my adventure with Simplistic this is a realy good way to learn things (which is what interest me) so I will give the small capacitors a try and for this I tank you.

I got a board ready for Gyrator folowed by 317 and I will put the caps there and see.

You're welcome and I'm glad if I can help you. Aside audio design it's common known that those little "dears" need thos caps.

Anyway, I think with Salas low voltage regs you don't need a LM in front, so just go for a good energy storage with LC or RC filters.

Another way is, like Salas mentioned to use batteries ... but this is another cup of tea.

Have a look at Thel Audio
 
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Thanks very much Salas. I've got a slight hum problem on one channel of the 40dB stage I built for my dad, but then this is next on the list (it only hums when arm an lead is connected, it does this with two different arms regardless if L or R leads are connected).

As an aside, have you though about adapting this circuit for use in R2R's and cassette decks? I bet this circuit would sound fantastic when used as a play amplifier in one of my Nakamichi's :)

I would be willing to give it a go in either my 482 or 482Z
 
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I had only designed in a couple of NAB curves for open reel for a member who wanted to test but I don't know if he ever did. For hum in a custom build only when the arm is connected, its you must find the wrong ground loop and revise it. I can't know what's routed and how there, naturally.
 
You're welcome and I'm glad if I can help you.

Another way is, like Salas mentioned to use batteries ... but this is another cup of tea.

Have a look at Thel Audio

Tanks as one need all help he can get...

I started up with bateries for a INA like mc stage I designed about 3 / 4 years ago it had 6 LT 1028 and a couple off DC servos.

The charger was a LM317 with a transistor for costant current.

But I wanted to go away from 8 leghed critters and learn how to use transistors and Jfets.

IMO the simpler the circuit the better it sounds
 

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Thanks very much Salas. I've got a slight hum problem on one channel of the 40dB stage I built for my dad, but then this is next on the list (it only hums when arm an lead is connected, it does this with two different arms regardless if L or R leads are connected).

Sorry to but in Hum in mine is with 60 + dB gain for moving coil.
With 40 dB gain I may presume vrongly that you are using a MM cartridge.

If so, I may be wrong again but MM may have one of the pins connected to ground so there may be ground loop there.

OFF topic.(I been Acused that I listen to cheap records which is actualy true):D

My kid is in UNI at Shieffield so I will be there eventualy could you give me same pointers for the best record shops in there...

OFF OFF topic Picture onethe cheap one actualy sound better than the one in the box set for 1/30 price.

Picture 2 the old one on top is original Shanachie the second one is Island reprint the old one is scrathed the Island reprint has not only quite a bit of his from master tape but also One could clearly ear the Echo of the first notes before the actual music start (poor cutting)

I listen to the scratched one normaly:D

The litle one on the side is Just a teaser...
 

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Picture 2 the old one on top is original Shanachie the second one is Island reprint the old one is scrathed the Island reprint has not only quite a bit of his from master tape but also One could clearly ear the Echo of the first notes before the actual music start (poor cutting)

I have on disc where I can hear notes before music starts and I believe that is an indicator that the master tape is analog. I also experienced the same effect in some old tapes I have got... When in storage, if the tape is tightly wound, there can be an image formed from previous notes, because the tape is overlaping in the reel :)

No hum in any of my builds :)
 
Tapes one thing records is different.
If you push late to hard it deform the previous or next groove next grove you can't hear as late cancell out the "spurious" noise by cutting over it The previous grove is ruined and no going back to it. Unless you start again.

But big company does not realy care for records that do not sell much and normaly does a rush job of it especialy if they do not own the artist.

Riccardo how old is the record you mention?

Tape analog yes especialy for late 70 records.

I don't realy want to get in to an analog digital debate I do have an Ipod after all but IMO digital is what killed the art. to easy to cancell mistakes and dinamics are so much compressed on late stuff...

A bit like listening to a BBC or ITV program I did not realy understud what the fuss about Paul Potts was till I heard him sing Nessun Dorma on the BBC.

Get searching for original Shanachie stuff in the second hand shops probably the best £3.50 you ever spent.

PS the are in Newton NJ USA so you may find much more stuff than what we get this side of the pond
http://shanachie.com/

http://www.discogs.com/Chieftains-Bonapartes-Retreat/master/284347
 
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