Taddeo Passive Digital Antedote II
The first device I’m going to talk about is the Taddeo Passive Digital Antedote II… which I’ll call the PDA2 from here on in 🙂 This unit was sold and marketed by Taddeo Electronics at one point, which was designed to create a more liquid and less digital sounding source when using CDs for musical reproduction. A lot of people thought it a bunch of Nonsense, but this device might very well have some merit.
I have attached a schematic I made up of the Taddeo PDA2. It has the
component values on it. It shows just one channel. It’s possible that this schematic is a trade secret of sorts, but who knows… its now here for all of you to see.
A word on the components:
Resistors:
R1 is 1500 ohms
– I have used both metal film & Carbon composite
– no need to use greater than 1/4W. I’ve used 1/8W & 1/10W
– use low tolerance. 1% or better. I’ve used 0.1%, too
R2 is 640 ohms
– I’d use metal film only here 1/4W or less
– the tighter the tolerance, the better 1% is the maximum I’d go with. 0.5% or 0.1% would be even better
Inductors:
L1 & L2 are both 18mH
– try to get 5% tolerance, but 10% will do
– these will be handling very low voltages, so small iron-core types are fine. No need for air-core designs unless you want to spend a lot of money
Capacitors:
C1 & C2 are both 1.8nF
– good luck finding this value 🙂
– try for 2% tolerance or less. 1% is good & you might still stand a chance of finding something. Caps supposedly come in even tighter tolerances, but good luck, especially with this unusual value
– Mica caps give a slightly brighter, more detailed sound, polyethylene or polypropylene will be a bit mellower. Tantalum may work, but will be bright. Don’t use cheap polyester caps. I’ve used both mica & Philips PE caps with good results
The schematic has the components laid out in their proper physical layout, too. The schematic in the patent is a bit more confusing.
This device goes inline between the CDP or DAC and the preamp or, if you use higher wattage rated resistors (1/4 or 1/2W), between the preamp & power amp. Note that this may benefit tuners, VHS & cassette tapes, but will do only harm to the sounds of vinyl.
Most of the parts for this unit are available from Digikey or Allied Electronics or can be sourced locally… I’ll be interested to see if anyone tries to build this unit as it! Let me know what you think.
Schematic:
I have limited knowledge of diy other than cables but, I would like to try this. This may be a stupid question…would I build two of these (1 for rt & 1 for lt) and hard wire quality RCA’s to each? I would think that’s the case but, please tell me if I’m wrong. Thanks for the posting. Best regards, Wayne.
You could build it any number of ways, with a box and RCAs for both in and out or build the cables right into it as a box part of a cable… or build it right into your source component.
Hi again, I’m trying to find what I need thru Vishay…we’ll see how far I get with that. I think I’ll hard wire to the input side and use my silver interconnects on the output side. I have a Vincent cd-s6 tube hybrid CD player with Telefunken 12ax7 and Mullard ecc88 tubes to a Parasound Halo P-3 preamp and (2) Halo A-23 amps in a passive vertical bi-amp configuration feeding a pair of Legacy-1 loudspeakers. All cables are hand made. One of these days I’m going to try my hand at a turntable. Wish me luck. Wayne.
Hi Nelson, this is what I’ve come up with so far from digikey :caps @ 1500pf-500v & 2000pf-500v. resistors are 634 & 649 both 1% & 1/4w. What direction would you suggest? Thanks, wayne.
ok, i found 1.8nf mica caps…what about the voltage? 100,300 or 500?
You will need to pass only 2v so anything rated for 4-5volts and up is ok.
The lowest I have found is 100volts.
that will be fine. it is a rating meaning that it can handle anything up to 100v.
Thanks Nelson, that gives me some room to play. I’ll let you know how it sounds.