Simplistic NJFET RIAA

diyAudio Chief Moderator
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So you have 21dB line gain and a normal gain main amp (28-31db?), plus 94dB speakers and you have a not enough volume problem with 66dB gain phono?

In that matter the Simplistic Riaa will not help since it will not go more than 64dB with a couple of Rs bypasses if not to be compromised for choices and hiss.

Its weird that you don't get enough volume with such a system gain structure, something appears wrong, by the way.

EDIT: For materials try Mouser. 3.3V no simplistic shunt since the Mosfet only, needs 4V to open.
 
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The main amp gain is 26 dBs, you'r right I do not need more power at the final because is very easy to get SPL of 114 dBs or more with the DAC (cs8414+dif1704+pcm1704+i/v Erno Borbely). The reason is that I prefer to have more gain in the analog front end & not increase the level with the line amp, possibly the solution is to buy another mc cartridge with more gain like the AT33PTG with 0,5mV, could you recommend any other good mc cartridge for the Linn Ekos?

Ok I understand that is not possible to do a shunt for 3.3V:mad:.

I asked a quote for Spencer to get sk170bl, if is not possible to do with the lsk389?

About Salas simplistics riaa due to the fact that I will do mine own PS, I need to know: how many VA needs the transformer (I suppose will be the same for all shunt regulators) & will be the voltage needed at the seconday depending each combination for the Universal Simplistic Phono Shunt Salas 2009:confused:.

Thanks for the Mouser supply information:)

As always a lot of questions, thks for your kind advice.

merlin el mago
 
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1. I still don't see the problem if to use more volume range provided you don't have annoying hiss?

2. Benz ACE Red a friend has and I like it enough. Goes about 0.45mV in practice and with its 12 Ohm source, you start with good SNR. Investigate Ekos compatibility.

3. Of course LSK389 will do. It has naturally matched duets and that is handy.

4. You need to download Psgr's pdf that has a nice roundup of all versions and BOMs. In general, a 50VA Tx will do.

Regards
 
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He will have to tell us if his Rapidshare link is still alive. He had posted it some time ago. Do a search using his nickname and go through his posts.

If you have enough LSKs between 8-9mA Idss, no changes.

For the Ace Red my mate has the 56dB MC version, a 12B4 10dB gain pre, a 20W 33dB KT88 amp and 88dB speakers, all DIY. It really rocks with volume. I still wonder why you want to lose useful rotation on your volume control. You already have a 66dB Linn phono and 21dB line gain... Should do the 304 greatly.
 
Hi Salas. Did you succeed in making your RIAA stage in its latest version as per post #2652?
Better sound with low MCs even if not using the shunt reg v1.1? Lower noise?
I was also wondering if adding R9 and using 4 jfet in the front end could be benefical even in the std MC (56dB) version towards noise.
 
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From France but looks noodles to me too. One from that series was at least tested by Roender in an amp for very low field.

The Hammond is OK, but has edges, R-Core is named after race track shape, so it is the best bet in a phono box. DC-B1 is much more away from trouble with 2VRMS signal level VS 0.25mV RMS that I will try to handle here.
 
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I would also like to avoid two cases for a 56dB riaa....

As I will need 37v from the shunt and using my actual supplier the best option is a 2x18v toroid wired in series to get 36v (2x15 is a little short due to the mains fluctuations).

Is it possible to get a comercial r core TX ? or are those only made by special order ?
 
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You will find an American maker, a French seller, and Asian sellers. Which one is made to spec for hum field kill and the quality of laminations between them on sale I have no experience of. The former quality is of most interest here. A correct R-Core in right angle with the boards at max distance in same box has to be tested is my aim.