Simplistic NJFET RIAA

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Is it a bit verging to the ''analytical'' side that AT in the real life system? In the files it gave me a feeling of not so full mids and rather processed like highs but I don't know how much of that hint I could allocate to the PC's ADC, software, PC replay again, etc.
 
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P.S. Is that u1J63 an MKT or tiny MKP for interstage coupling? Maybe something like an Auricap or PIO can make a difference there.
 

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Hi Salas, it was a 100nF MKT initally, I've replaced them with a 100nF polystyrene now.

Yes I agree it does sound very analytical, I think this is a trait of all AT cartridges. I also have a Denon DL-304, an Entre EC-1 and a Dynavector DV 23RS which I will be getting rebuilt. All of these are more evenly balanced than the AT (but the AT worked really well with my old phono stage)
 
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diyAudio Chief Moderator
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How is it on your TDL speakers? Is it well tonally balanced, has good projection, bloom, detail, in right proportions? If yes, don't try other parts.

P.S. Just saw your edit about carts available. If you can get a couple of cheap 0.1u K40-Y ebay Russian paper in oil to try for interstage, they could possibly mellow out the AT & polysterenes combination a bit. Alternatively you can add one or two 100pF caps parallel to your Riaa HF cap (15n) step by step and see if it rounds a bit just before getting out of proper HF balance.
 
I'm currently using my Kef Reference 103/4 that I've re-foamed and upgraded the crossovers, the TDL's are in storage. Power amp is a dual mono HackerNAP (NCC200/Naim circuit with front-end regulation and optimised layout), Yes it is all tonally there, it is just so much cleaner than any other phono stage I have used.

Some more clips, this time with an Entre EC-1 which should be slightly less strident than the AT33:

Adele - Adele_Salas_Entre.wav
Supertramp - BloodyRight_Salas_Entre.wav
Hendrix - HeyJoe_Salas_Entre.wav
Them Crooked Vultures - Vultures_Salas_Entre.wav

The levels aren't perfectly balanced, I am yet to put a signal generator on it and measure the gain on each channel and I think the right channel is slightly lower.

I think ultimately I plan to use the Dynavector with my new tonearm, when that arrives and I get the cartridge re-built I will look to optimise the phono stage.

What made a big difference in my build was earthing the GND rail at the output of the reg to the case (which is earthed at the mains) with a very short piece of wire, so that it has a low impedence route to ground. I now how no hum at all, even with all the other stuff in there :)
 
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diyAudio Chief Moderator
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I had kept Adele with AT33 and listened to one after another file also listened to the others. The AT surely extracts more. Also has a hint of more level to the left hand speaker (as we face the speakers) but on Entre that mismatch is accentuated. On Entre I found the sibilance more open and natural, the whole balance meatier, but less transparent than AT. If you could have the resolution of the AT and the tonality of the Entre in one package it would be great. Still can hear they come through the same PC recording chain, I don't expect I get to know how it really comes across on your KEF 103/4s in your room, but its interesting that the two carts can be still clearly picked up. Its difficult to say there is something you can surely trim for HF Riaa balance since in one cart its nearly much when in the other its nearly lacking in level (On Adele, because on Supertramp the Entre had enough HF too, is ST on thinner vinyl?). Such a thing gets to listen to many cuts to know how it sails through a collection for brilliance. Maybe you can ''open up'' the Entre or ''tame'' the AT with experiments on loading resistor values, VTA, VTF, etc.? http://www.walkeraudio.com/fine_tuning_your_turntable.htm Regarding the channels level match, get a test record and match with the used cart as source, so you can dial out the coils imbalance at the same time. A commercial open loop would not know what to expect so it would be using gen for L=R, but this is DIY and you can offset the cart's L/R balance too. Your build has ended up demonstrably successful after enough board debugging and complex systems housing ''co-existence'' hum kill, that is rewarding. Congratulations.
 
Thanks for your comments Salas, and thanks again for your help with my build. What is clear it is a great circuit - all the musicality is there that we all love in vinyl but the level of transparency and detail is superb and far above what I thought was possible from vinyl. I have also learnt alot from this project (which is possibly the most important thing) and plan to build a 2nd pre-amp for my main system with a DC-B1 and one of your Simplistic phono stages. I have also promised my dad one as well so I will be very busy through the winter.
 
Advices on Pre Phono

Hi everyone.
I'm starting to build my first project. A pre phono optimized for Denon DL 103.

First of all I want to SAY THANKS to:

nicoch46: He worked a lot to make me understand the basics of my project. It's my fault if he was making a lot questions to you guys. I WAS THE REASON :). Thanks again nicoch46

Salas: I don't know, I never talk to you to avoid confussion. Nico was making questions to you answer me. This because I'm a rookie in electronics and can't make the right questions by the moment.

Cruz. Thanks for your great advices.

I'm planning to use:

Two R-Core 30VA 2x18V. (one per channel with the coils in series to reach 36V)

Shunt: SALAS Version BIBguideRev2 - (Kit from TeaBag)

Pre phono:


The project is yours Salas. Nico gave it to me because I told him I have a Denon DL 103 on my Thorens TD 146.
Any suggestions... can I proceed in this way?

Remember: I'm not an expert like you guys. I just want ear the music in a better way. I listen Rock, some electronic music, pop, jazz (I love Miles Davis), blues.
I like deep bass and not to brilliant flutes.

THANKS THANKS AGAIN
Daniel
 

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the pics attached to the last two posts display differently.
post6795 replaces the DIYaudio window to display an out of focus 26kB view, whereas post6796 expands the pic over part of the DIYaudio page and allows the pic to be moved around to enable the post to be read. This pic is only 8kB and yet the detail is crisp and legible.

Because of this difference in display it is more difficult to compare the two schematics.

How can this "replace DIYaudio page" be avoided?
 
diyAudio Chief Moderator
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Salas: so can I go on with this last scheme?...
Thansk again all of you guys.

nicoch46, Cruz and Salas.

I will keep you posted with my work.

Yes do that. Its one piece, easier for you. df_genius had very good gain with Entre EC-1 0.2mV with a one piece 60dB, also very low hiss in as much we could understand from his .wav files.
 
diyAudio Chief Moderator
Joined 2002
Paid Member
the pics attached to the last two posts display differently.
post6795 replaces the DIYaudio window to display an out of focus 26kB view, whereas post6796 expands the pic over part of the DIYaudio page and allows the pic to be moved around to enable the post to be read. This pic is only 8kB and yet the detail is crisp and legible.

Because of this difference in display it is more difficult to compare the two schematics.

How can this "replace DIYaudio page" be avoided?

Was embedded, got it out 4U. :captain: