Simplistic NJFET RIAA

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What do you think about the Rike. I was considering it vs Audyn

No real listening time on them yet. And it will be a apples to oranges comparison, as I will have a MM cart on this one. But I should get a general idea.

The previous prototype was Audyn Reference caps, a step below the coppers. They were very nice, but the leads where thick guage speaker ones. The Audyn's were more neutral than Mundorf SIO, but still high resolution.

On the MM RIAA, the interstage is currently a MKP1837 .1uf, and I intend to swap it around for some effect later, to something else.

On the prototype, I will rework so I can swap caps out easily maybe to test them individually. But my time is limited. I have picking away at this project for quite a while.
 
Problem. The group of four should lit. Maybe all have been inserted the other way around, or even one inserted wrong can break the whole chain.

TP 1 to ground should go over 7V when the LEDS will eventually operate but no more than 8V. TP 2 to ground should be adjusted to 4V after that. Or TP 1 to TP2 for 3.6V difference, same thing. The PSU side sounds like doing basically well. But restore the four LEDS situation first so we will check the whole behavior better.

I was hoping that I had installed them wrong. The flatted sides are facing the cathode direction.

Should I replace these and see what happens?

Thanks,
 
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I was hoping that I had installed them wrong. The flatted sides are facing the cathode direction.

Should I replace these and see what happens?

Thanks,

When power is off, use a DMM in diode mode that you know it can light up an LED (some can't) or a 3V-9V battery pack or cell, and go (+) anode (-) cathode across each under PCB. Bcs another possibility that had happened before with LEDS is to burn one or more during soldering. One by one must shine in this test. If you will find even one bad apple in each group, then that's the broken link to replace.
 
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Joined 2011
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Fellow black gold enthusiasts, I'm seeking some advice.
I've broke my Benz Ace SM (0.8 mV) cartridge and looking to get a repair or replacement.
I'm offered SL or SH stock versions of the same cartridge by the company.
Second option, full repair of my SM that would take about 3 weeks and more.

Question: what are downturns or gains choosing SL / SH vs SM?
 
Something wrong in the signal side with a strong ground loop, or the bias is off in the stages, or the power side has a problem, I would look for. Can you post a photo of the build, and data about various points voltages in respect to ground? RAIL-GND, TP1-GND, TP2-GND, Q4 drain-GND, Q6 drain-GND. Are both sinks rising temperature?

Hi Salas,

Thank you for your support.

Your questions put me on the track! A rookie mistake, I am ashamed for telling you the truth.

Well, it is working like a charm.

It needs now a beautiful case, because (sorry for the quality of the pict):
An externally hosted image should be here but it was not working when we last tested it.
 
Simplicity itself

Hi.

Do you or Rick have a schematic of a suitable circuit?

Regards

I am still working on getting the basic circuit to work but as soon as this happens I am going to place the chokes within the box and close to the B+ input on the phono board place a approx 1800 uF cap across the + and -, along with the suggested 10kR bleed resistor as advised by SALAS.

The caps will be RIGHT AT the power input.

The existing wires from the standard supply are right at hand here - just splice it in.

Low resistance and as much inductance as your box will allow. I will be using some chokes Jeff Medwin got someone to make for him a few years ago for his LOFTIN WHITE based amplifier. Seven ohms resistance and 15/100'ths of a Henry - 600 mA rated. Leads are multiple strands of clear jacketed KIMBER wire. Don't know if he is still having them made. After giving up on making the amp they were intended for I have wondered where to put them to use.
 
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Thanks exactly what I did recently with one board, fixed it just by lighting the LEDS up one at a time on DMM and realizing one would not turn on!!

:rolleyes:

I always measure every component before soldering... than I solder the most sensible parts (like leds and fets) and measure those and in the end I start populating the resistors (also measured).

This way I always know where the problem might come from :)
 
Member
Joined 2006
Paid Member
Fellow black gold enthusiasts, I'm seeking some advice.
I've broke my Benz Ace SM (0.8 mV) cartridge and looking to get a repair or replacement.
I'm offered SL or SH stock versions of the same cartridge by the company.
Second option, full repair of my SM that would take about 3 weeks and more.

Question: what are downturns or gains choosing SL / SH vs SM?

Hi Siberia

I also have one benz Ace M that needs repair or replacement.... never could get in contact with the company.... would you please PM me some coordinates ?
 
My first attempt at semiconductors ...

I always measure every component before soldering... than I solder the most sensible parts (like leds and fets) and measure those and in the end I start populating the resistors (also measured).

This way I always know where the problem might come from :)

and I have much to learn.

Your advice will be remembered for the next project, I can assure you.