Simplistic NJFET RIAA

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Yes that's the top to floor distance, its a tall enough double cabinet speaker. Used to have an Audax dome tweeter but I upgraded to horns for the sake of controlled directivity which suits my room better.
 

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Wow. These are very nice looking speakers and based that you made these, I’m sure they are sound amazingly well. You are already repeated Dr. Pavlov dogs salivation experiment on us. I’ll be your follower if you will decide to open new thread for you speakers design DYI. In serious note, room’s acoustic is not that easy subject (someone wrote that acoustic design is a hundreds compromises and equation with infinity amount of variables) and all of us might get different results, but any way it is make sense to try.
 
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I built it for MM or MC part values as listed in the guide but not with switches. A Greek guy in a local forum built it with female pin headers for each differentiating component to can simply change them without desoldering for another cartridge type in the future and it works without noises (for now). Fortunately its about rather few components to change its sensitivity version.
 
I've build mine too, with female pins, for MM and Low MC, no problem if done properly.

First solution I thought: small diy pcb on top of the pcb attached the pin headers for quick swap

Second solution: buying two boards from Tea-Bag and stuffing the second one with only the gain section (no simplistic psu, no RIAA). It will be attached to the first one with two relays, one before the setting resistor (R12+trimmer) and the other before RIAA cap (C3). This way you don't have to buy another set of signal caps (4 of them), big pros for those with expensive caps

Third solution: buy two sets of Folded phonos. Very useful for the people with two turntables

What do you think of the second solution Salas ?
After having the phono for so long and going toe to toe with a much much more expensive commercial one, I consider this as the weakest point.
 
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I think that's a good solution architecturally speaking but it remains to be proved if it will be sensitive to noise or not because of the relays and wiring between two boards.
If done properly, it's a minimum wiring solution, 1 cm for the header to connect to the second board (upside down). Forgot another relay at the input. This relay and the one at the input of RIAA are the most critical and should use minimal wiring, millimeters if possible.

One minor downside is that you'll have to wait for the warm up period for each gain section. Using another simplistic psu will bring up more heat.
For such small signal does the normal relay type (say the one from I-Select) qualify ?
 
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The Valve Itch is a good option if looking for original vacuum triode sound qualities, has meatier impact across the range, but this one has more resolution due to lower intrinsic noise floor and much higher transconductance while being smooth. Also follows a classic architecture like most valve phonos do. Block by block with passive RIAA and no loop feedback. JFETs are like solid state pentodes save the heaters. So there is more consistency between the two phonos than one might initially think.