Simplistic NJFET RIAA

You know how subjectives are, don't make a move before something sounds weird after you have installed decent components anyway.
Don't worry! I try to avoid reading opinions about caps and wires. Like in that other thread you referenced, where ZN's were either "harsh" or "neutral" or "dull". For that matter, I believe that if you installed a switch on the front panel of a preamp, and connected nothing to it, some audiophiles would spend a lot of time debating the sonic signature of each switch position. :D

I'll take my chances with the over-priced snake-oil caps I already bought! If they sound really bad I'll replace them with decent-quality non-boutique like Wima or Epcos or Vishay.
 
When do you think you will be at 100% BOM and starting?
Delivery is bound to be a bit slow this time of year, but I hope the Mouser order will arrive before Christmas.

First step will be to lay things out and figure out what size cases I need; my last build was too tight because I ordered the cases before I had a chance to really see how things fit together (it was mathematically correct, but mechanically bad). Then I'll start soldering. I got some nice cases last time from a place in China, and the delivery time was surprisingly short, the quality pretty good, and the prices amazing. Similarly, I already got some of those aviation 4-pin connectors from a Chinese PC-mods place at crazy low price.

So I'm off work next week for the holidays and will try to get some time to work on the boards. I should have my FET's/LED's sorted by then. I also have some 2sa970's on order; if they arrive in time and measure OK I'll use them, else I'll build with BC560's and consider replacing them later to compare.

One doesn't want to rush these things, else the unit is built and I have nothing to do! :)
 
Wet them cable ends in solder at least.

My terminals are ex-military and silver plated.
Found them in local surplus store.
They are very stiff and should be no issue with them ...
I always use solder (BWT currently) to finalize cable ends.
Never used any sleeves till now.
BTW, for correct sleeve installation you need to use special crimp-pliers.
I do not have it yet....
 
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I may be trying to read too much from between the lines of various "test reports" on LED noise, but I get the impression that lower voltage LEDs (lower Vf) tend to be quieter than higher voltage LEDs.
This certainly applies if you only consider infrared and yellow/green and blue and white.

The blue and white are much noisier than the yellow/green.
The yellow/green are much noisier than the infrared.

This would suggest that a low voltage red may be slightly quieter than a higher voltage red.

But this is only my conjecture after reading quite a bit. I do not have the resources to check the results.
 
Screw terminals are ok if you terminate the wires properly with Cable End Sleeves like those from WBT or others less expensive.

Just terminate the cables and screw them tight..

My terminals are ex-military and silver plated.
Found them in local surplus store.
They are very stiff and should be no issue with them ...
I always use solder (BWT currently) to finalize cable ends.
Never used any sleeves till now.
BTW, for correct sleeve installation you need to use special crimp-pliers.
I do not have it yet....
You don't need a crimper.

A close fitting thimble over the stranded wire ends will be crimped when the screw terminal is turned down hard.

The cross-sectional area of the thimble will be bigger than the cross-sectional area of the cable. That equals lot's of air/gas between the wires.
Screw down on the thimble and the area inside the squashed oval is less than the circular cross-section. Screw down hard and the kidney shaped cross-section inside the deformed thimble is now less than the cable cross-sectional area. The wires get deformed and you end up with "gas tight" joints between the strands and between the thimble and the wires and between the thimble and the enclosing terminal.

It's the "gas tight" that gives the excellent long term electrical connection.

And a thimble replaces the need for soldered ends and is FAR BETTER than soldered ends.
I don't have any thimbles. I wish I did have a range for all my cable sizes. I would use them.
 
I got some nice cases last time from a place in China, and the delivery time was surprisingly short, the quality pretty good, and the prices amazing. Similarly, I already got some of those aviation 4-pin connectors from a Chinese PC-mods place at crazy low price.

Would you share the links to these vendors? I'm waiting for C3/C4, 2sk170bl's, trafos, Welwyn 0,1% resistors and Vishay VAR's for RIAA and R1/R14. Then a test in free air and decide boxing...

Regards
 
Boards are now ready for powering up!
I used polystyrene ERO kp1834 5% for the treble RIAA cap plus trim cap which gave me a value of 15.18nf and 15.15nf. Readings where taken with a very cheap DMM so i know that are not accurate. If the sound is weird i will replace them with mkp1837 caps as per guide. The smd resistors are TNPW and r13 is Royalohm 1% 2w MF 50ppm. Output cap is JB JFX which are a pleasant surprise considering the fact that they are really cheap. I tried these as coupling caps in my AD1865 dac, and they outperformed Mundorf white MCap, Solen and Κ73-16. So until i can afford Mundorf supreme these caps will suffice.

Hoping of listening to music this night and not debugging! :)
 

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