The Zen Triode Phono Stage is an all tube, single-ended design built using the popular 12AX7 dual triodes for amplification and equalization and a 12AU7 dual triode as a cathode follower to lower output impedance for better stability and drive.
Besides being comprised of all single-ended triodes, what makes the ZP3 desirable is the complete absence of negative feedback which is typically used to accomplish the RIAA equalization. Instead the ZP3 uses a passive RIAA network between the two 12AX7 gain stages. This approach gives a more open sound with a greater sense of depth.
Additionally, the ZP3 has a power supply over 500% larger than needed and with enough capacitance to easily power a 40 watt amplifier. This was done to eliminate voltage sag by brute force rather than using a smaller power supply and fancy solid state regulation which is the norm.
To take the power supply further, a vacuum glow tube is used in series with the supply to block harmonics and RF noise on your local power grid. The result is like having pure DC power from a battery. It is a superior method of cleaning power that does not rely on power regeneration which is often noisy (fans) and will cost several thousands of dollars.
There are no solid state parts in a ZP3. Often used to regulate smaller power supplies or create a constant current source for tubes, these solid state parts have been deliberately omitted so that the resulting artifacts of those devices do not poison the signature of the ZP3... a signature that has been painstakingly voiced and is completely unequaled in the market for anywhere near the price.
Tone Audio Magazine issue 74.
"I continue to be impressed by the tonal delicacy,
richness and contrast this phonostage offers. Unless
you have an ultra megabuck analog setup and system,
I’d highly suggest buying a Decware ZP3, the matching transformer and calling it a day. It’s that good. And
it’s good enough to get one of our Publisher’s Choice
Awards next issue, too." – Jeff Dorgay
ZP3 LAYOUT
The ZP3 is constructed on a heavy gauge steel plate that screws down into a solid hardwood base. The layout shown above is also in the owner's manual. The bottom of the illustration represents the front of the ZP3.
- Single Ended Triode
Passive RIAA No negative feedback
- Tube voltage regulation
- Tube rectification
- Self Biasing
- DC Heater supply
- Custom transformers
- World AC Voltage Compatible 50/60Hz
- Removable power cord
- High mass chassis
- High Reliability
- Silent noise level
- Optional hardwood bases
- Reference fidelity
- Premium hand selected and matched tubes are included
- Optional NAB and IEC equalization for Tape
- Lifetime warranty
The ZP3 has a few options that can be selected from within the shopping cart.
Voltage: We will automatically select the correct power cord for your country. 110/120 Volts is compatible with Japan. 220/240 Volt models can be re-wired for any country including the USA.
Capacitors: The output signal capacitor in a ZP3 can be upgraded to Jupiter's cryo treated beeswax caps. The standard audiophile cap in a ZP3 is made by General Electric and is a high quality Film and Foil polypropylene capacitor. It was the only capacitor option in a ZP3 until 2015. If you're on a budget, these G.E. capacitors are more than adequate, and are what were used in the review sample sent to Tone Audio Magazine.
Wood Base: The wood bases for a ZP3 are interchangeable. Some choices carry an up charge. If you want a wood that is not listed in the cart (including any exotic woods) select Custom Woods and write what kind of wood you want in the comments section of your order during checkout. We will contact you for additional details. Below are some picture of the standard wood bases offered and some examples of other woods.
Standard Walnut Base
Standard Black Molded Base
 Natural Cherry Base
Natural Blackwood Acacia Base
 Natural Zebrawood Base
We can do almost any custom hardwood by special order.
THE TAPE OPTION
If you're a tape lover you'll be interested to know about the ZP3 tape option.
By having a tape machine modified (shown above) with a pair of RCA jacks wired directly to the playback head, you can have pretty much the holy grail of sources... guaranteed to beat even the most expensive vinyl rigs.
Natural Cherry Base
The tape option consists of a couple switches to go between tape and LP as well as some calibration controls for the TAPE EQ. Shown above you can see the switches and calibration pots on the front portion of the ZP3. The center switch is an impedance switch that goes between 47K for vinyl and 600 ohms for tape heads. This in and of itself can be a valuable voicing tool during tape playback since one setting is more open and textured and the other is more disciplined and reserved.
You probably have a wide variety of tapes and no doubt some sound better than others. Using the calibration controls that set the EQ from NAB to IEC (or anywhere before, after or in-between) you can literally extract magic from every tape.
This wonderful little feature can be a real game changer for serious tape enthusiasts! If you only knew what was hidden in those flat or sharp or lean or fat sounding tapes... it's astounding! The range on the EQ is massive. When you're using it to dial in a tape, the process is not unlike tuning in a radio. It's such a powerful tool you simply have to have it.
MOVING
COIL
CARTRIDGES
For moving coil cartridges, we offer three ranges of Step Up Transformers.
Model ZMC
|
ZMC1
|
For low output MC cartridges
|
1:20 ratio for use with 3~25 ohm
cartridges.
|
|
ZMC2
|
For high output MC cartridges
|
1:10 ratio for use with 3~100 ohm
cartridges.
|
|
ZMC3
|
For high impedance MC
cartridges
|
1:12 ratio for use with 25~100 ohm
cartridges.
|
All three models feature adjustable live cartridge loading via the gold knob
on the front of the unit so that you can adjust the loading of your cartridge on the fly and by ear. Simply turn the knob up until the music stops getting louder and that's the ideal loading for your cartridge. From that point, you can adjust the loading up or down to effect frequency balance.
ZMC's are located here.
SUPPORT
The ZP3 is hand built in the USA by
DECWARE / High Fidelity Engineering Co. It comes with a lifetime
warranty to the original owner. If you purchase one second hand and
ever have questions or technical problems we WILL be happy to check it
out for you and service it if needed for a very reasonable rate.
We also
have a support forum
with
many people who own this amplifier who's experiences you may benefit
from.
REVIEWS
This amplifier requires no adjustments or maintenance other
than changing tubes every couple years.
| Weight |
|
13 lbs. ea. |
| Dimensions |
|
8.5" H x
7.250" W x 14.75" D
|
| Circuit
type
|
|
Single
ended Class A Triode Passive RIAA
|
| Gain |
|
+ 42 dB |
| With
optional
|
|
step up
transformer + 61dB
|
| Input |
|
47 kOhm |
| Noise / Hum |
|
< 0.5 millivolts
|
| Input
Impedance
|
|
47 kOhms |
| Output
Impedance
|
|
< 1 kOhms
|
| Feedback |
|
ZERO
negative feedback used
|
| Rectification |
|
5Y3GT / 5U4 tube
rectification
|
| Regulation |
|
OA3 tube
regulation for entire circuit
|
| Signal
tubes
|
|
12AX7,
12AU7
|
| Biasing |
|
Self-Biasing
circuit
-
never
needs
adjustment
|
| Resistors |
|
All
resistors are audiophile grade
|
| Signal Cap
|
|
Audiophile
grade poly film/foil or cryo treated beeswax
|
| Filter
Caps
|
|
8 x 47uf 500V F&T
|
| AC cord |
|
Fused IEC
connector provided with removable power cord
|
| Consumption |
|
65
watts
at
full
power
|
| Input
jacks
|
|
RCA / Gold
|
| Output
jacks
|
|
RCA
/ Gold
|
| Warranty |
|
Lifetime
to
original
owner
/
90
days
on tubes
|
VOLTAGES
This amplifier comes standard with our World Voltage Compatible
Transformer. Your ZP3 will be automatically wired for the correct
voltage for your country and be supplied with the correct removable
power cord.
DESIGN NOTES
The ZP3 Design
Notes by Steve Deckert
|
