Jocko CD80

Thank god someone actually builds something and doesn't sit around simulating all day. It sounds excellent and absoulutely no simulation! Jocko designed the discrete I/V stage 13 years ago.
 

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Jocko:
Your board looks really good. Too bad it cannot be used in balanced setup (or at least that was my impression). But to modify players it's perfect. Also the chips you are using, when implemented correctly sound terrific. Good idea is to use quality, separate VCXO.
Do you also have board to remotely control Alps pot. That might be of interest to quite a few people.
 
Harry:

You can use it balanced with 2 mods.

1.) Run either the LData or RData into both DACs.

2.) Invert the phase pin on one of them.

Then you need 2 boards.

I use balanced for my setup, but none of the people I do work for have balanced. And it was designed to "fix up" players. I have other designs for stand alone D/As. But they do not sound as good as an "all-in-one" unit. Even when I design it.........

The pot came with the CD-80. I had to move it a bit to make it all fit. I think I have a few left from people who didn't need a volume control.

Mozfet:

Stop using those things! Or buy my surplus ones.

Jocko
 
DVD mods??

Are you nuts? What am I going to do with one of those SMT parts farms? Shove one of my "whiz-bang converters" in there. I don't think so. Jocko don't play that.

Stinky, eh? Unwashed lederhosen, yep, that is stinky.

Harry:

Hear any "digital" or harsh sound in my player? Any lack of bass?

(dramatic pause........no response.......)


No........I didn't think so. All done sans '1541. (And you Europeans thought I don't know any foreign languages.) [joke]

Jocko
 
OK guys first clue...........

Look at Nelson's I/V. It is probably the same type of thingie. Just put a BJT where he uses a MOSFET.

MOSFETs are transconductance devices. Current in, voltage out. It works, but I prefer BJTs. Transresistance types: current in, current out.

Then convert the current to a voltage with........a resistor. Just like some guys do without having to build an amplifier after it. Paul McGowan.......you still aren't paying attention, are you. Thought so.

As for "Ren".......I'll deal with you later.

Jocko
 
Hey Jocko,

I surely miss something, but
Look at Nelson's I/V. It is probably the same type of thingie. Just put a BJT where he uses a MOSFET.
MOSFETs are transconductance devices. Current in, voltage out. It works, but I prefer BJTs. Transresistance types: current in, current out.
Then convert the current to a voltage with........a resistor
Isn't it the case here in this common gate arragement ? Drain current variations are converted to voltage ones using the 1K5 drain resistors...

Did you made comparison between Mosfets/BJTs, varying bias current ?