Simplistic NJFET RIAA

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healing after surgery

Just a quick post to report sound evolution...

Bass is tighter but with less presence and bloom. Highs are sweet but lost the slight "zing" in the transients.

But the real gains are felt in the overall integration... This mod enhances "sing factor".

Electric guitar gained in attack and presence.

Image is wider, taller and has more depth.

I conclude that the PIO is not the optimum choice if you want the best detail and imagery. perhaps silver mica is even better here. (I am writing about replacing the 47nF in the riaa eq circuit by a obbligato).

Ricardo

PS

Also read that the majority of the reedits in vinyl are made from DAT tapes (easyer to use in the pro circuits).

My best vinyl pressings where imported from UK between years 1975 1982.

(Local pressings lost something in the process.)
 
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Hi Salas

I believe I do not need the 101b internal Riaa circuit.

So my idea is to replace the 101b internal head amp + riaa eq modules by a modded board based on a meridianMC module I bought in the net (Worst riaa amp module I ever heard) that I itend to use as a signal bypass wire.
I will remove all the components of the MC board , and use shunts between the in/out golden sockets.

This will enable me to use the CDP in the (TAPE) in and the new Riaa in the phono input as actually they share the same input:D

My main issue is the salas riaa impedance matching... what should be the minimum ohm value in the 101b input ?

Ricardo

PS:
The other solution would be to keep tha actual MM Riaa with the second TT and Denon 160, and build a switch inside the Riaa Case to divert signal from the CDP/Riaa into the 101b TAPEin.

In this case I have the issue of another switch in the signal line and the CDP signal will enter into the Riaa before going to the preamp.
 
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RCruz said:
Hi Salas

My main issue is the salas riaa impedance matching... what should be the minimum ohm value in the 101b input ?

Ricardo


Yours has a buffer, but I would not stress it if I had a choice. Say not lower than 22k. Of course it can do much lower (I have a friend he uses it with 15uF output capacitors after the buffer stage on a 4K7 pot preamp). But I don't think that it helps the sound to go that low anyway.
 
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The TAPE in has a series 10k resistor before a 10k vol pot, followed by a 10k balance pot, before the opamp and sounds very good.

If I choose the phono (modded), I do not have the 10k resistor in series but I have an (impossible to remove) 470k to GND.

As I already have one 470k to GND in the Riaa, what can I expect from the additional value inside the 101 ?

Ricardo
 
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From what I see on this Meridian 101 schematic, you get 20K total through tape ''play'' input. The Meridian module sees a 470k so to refer its output capacitor to ground locally, as we do in our Riaa with 1M. That gives 9.79k load to the Meridian module when ''phono'' is selected and goes directly to its volume pot (10k). If you use your new Riaa with 470k on its output // 470k on the Meridian to its vol pot, then 9.59k it will see. Can drive. I don't know if your output caps on the new Riaa will lose some bass or not. What is their value? 2u2 if I remember correctly?
 
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Then, you will be OK.:)
 

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diyAudio Chief Moderator
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Heard them side by side. For background noise, the same as solid state. For Riaa EQ, same tonal balance. The tube one has more forward and juicy rounder SE tube amp style presentation. The Simplistic is more correct with more depth and detail. The tube one is better than the Bench cascode for comparing tube units. It does not enjoy a shunt yet, but a Maida. The Simplistic and the Bench have shunts. Maybe there is more in to it if with shunt, though I don't hear the Maida typical hardness on it due to its good PSRR being a Mu follower.
 
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The Simplistic is max bang for the buck. I know of people that will prefer the more enthusiastic Valve Itch style especially in rather dry systems. But under controlled, known variables, the Simplistic sounds more ''monitor'' without losing musicality. It remains to listen to the Itch with a HV shunt reg at a point.
 
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nicoch46 said:
with opa on output.....

nicoch46 said:
yes yes

Cruz look here

I know.. I know :bawling:

I am wondering if the space left from removing the MM Riaa will enable me to place a Burson V2 discrete opamp there... I know these do not need any output cap.

I did not give up my preamp project but I already spent a lot in building two pedja buffers with dedicated high spec +-15v psu that I did not finish:dodgy:

I must study the case intensely before moving on.

Actually I am amazed with the quality sound I am hearing in this new setup. (Maybe the 10k serial resistor was closing the sound a bit)

Ricardo
 
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nicoch46 said:
Cruz ,bass ?

I read a little on tone arm ,in general the unipivot have better air , bearings bass firm...12 inch aree better and have minor error traking

at fist nylon on 3009 was the upgrade on steel knife-edge ! after marketing go for steel.....try bronze....


This is a fine line of thought.. where can i find some suitable knife bearings ?