MODEL ZTPRE

  XLR Balanced Duel Mono Line Stage


Hand Crafted in the USA and sold Factory Direct with a
 
L i f e t i m e   W a r r a n t y  !

 

THIS HAS BEEN REPLACED WITH ZTPREv2

FIND IT HERE













While it might look great, it's really about the sound! The opposing layout of the tubes creates a small 2 x 4-inch  space between the tube pins at the correct angle where the entire audio circuit can be built using only the parts leads themselves.

When you look at how much this industry spends on cables and wires, it's not hard to realize that the only thing better than a preamp built around the world's most expensive wire is one that doesn't use any.The transparency of this approach is limited only by the tubes and interconnecting cables themselves which is a kind way of suggesting that this preamp will never be the weak link in your audio chain... regardless of how much money you may have wrapped up into sources and amplifiers.

The ZTPRE project was about figuring out how to wire the circuit with the absolute least number of nodes and how to keep the shortest distances between them that created this uniquely beautiful chassis design.




ZTPRE DESIGN SKETCH


Normally, a fully balanced circuit like this would be laid out in up to 144 square inches of chassis space where the ZTPRE has done it in only 8.



ZTPRE AUDIO CIRCUIT

The transparency of this approach is limited only by the tubes and interconnecting cables themselves which is a kind way of suggesting that this preamp will never be the weak link in your audio chain... regardless of how much money you may have wrapped up into sources and amplifiers.

A preamp like this one is very much like the preamp that you can't hear... except for the way it animates the music. It takes music that already sounds good, and makes it pop into a believable experience. It does this with dynamics, separation, pace, density and holographic imaging and does so against a backdrop of liquidity and intoxicating tone. These are all things which are the natural result of gimmick-free  circuit design and superior execution.






The ZTPRE comes standard with 1 pair of balanced XLR inputs and 1 pair of balanced XLR outputs.  Each channel's output has an output level control and master volume. This is the most 'purist' configuration with the least number of parts because there is no input selector.




Option 1 adds a Silver Contact Input Selector to expand the number of balanced sources from one to three.  The orange stars indicate the additional
parts for this option.

Option 2 is using stepped attenuators in place of the master volume controls. These attenuators divide the otherwise infinitely adjustable volume controls into 20 steps using 1% precision metal film resistors. This approach can bring more transparency to the sound and make it easy to adjust both channels equally by counting the steps as you turn them. The bad news are that these steps make it impossible to have fine adjustments to channel balance. So, surmise it to say some people like them and some people don't which is why it is an option on the ZTPRE. NOTE: The rear-mounted output level (trim) control for each channel IS a stepped attenuator and comes standard.






Option 3
is to use infinitely adjustable motorized Alp's volume controls that can be operated by remote control from the listening position. This option lets you raise and lower both volume controls at the same time with one remote. You can also manually make adjustments to channel balance and the relationship between the two controls will stay that way until you either turn the volume all the way up or all the way down which resets the balance to perfect center.  Watch the video above to see it work. NOTE: The only way to make this video was to plug the output of the ZTPRE into our ZDSD digital recorder so the sound you hear in this video is the actual ZTPRE.





ZTPRE REAR VIEW

Option 4 changes one of the balanced inputs to an unbalanced RCA jack by using transformer-coupling. This makes it possible to connect an unbalanced source to your ZTPRE by transformer balancing it. NOTE: Unbalanced sources are typically 2 volts, while balanced sources range from 3.5 to 10.5 volts. This means that if you use an unbalanced source with this option, it should ideally be higher output than 2 volts. A common way to accomplish this on stock 2 volts sources is to use our single tube device called the ZSTAGE to raise the voltage to 5 or 6 volts.

Option 5 is signal capacitors.  The ZTPRE is based on our highly successful unbalanced preamp design model CSP3, which has developed an almost cult following since 2006 due in part to its wonderful signature.  To maintain that signature in the new ZTPRE, we use the same audiophile grade film capacitors.  However, for those who want to kick things up a notch, we offer cryo-treated copper foil beeswax capacitors by Jupiter that we feel are the best sound money can buy for this product.







Included in the price of the standard ZTPRE is your choice between
Red or Black Face plates, and Black or Silver knobs.


Below are the four possible combinations:



RED FACE PLATE WITH BLACK KNOBS



BLACK FACE PLATE WITH BLACK KNOBS



RED FACE PLATE WITH SILVER KNOBS


BLACK FACE PLATE WITH SILVER KNOBS


All of the above options can be configured from within the shopping cart.









The ZTPRE is compatible with RCA to XLR adapters on the inputs, outputs, or both.  Alternately, you can configure it with transformer-coupled RCA inputs as one of the options in the shopping cart.



 

 

Weight   18 lbs. ea.
Dimensions   3.5" H x 17.00" W x 10.75" D
Circuit type   Single ended Class A Triode SRPP
Output   Adjustable 0 ~ 35 volts
Input voltage   10.5 volts RMS 
Noise / Hum   - 58 dB
Input Impedance  
47 k Ohms
Output Impedance  
600 Ohms
Response   5 Hz ~ 100 kHz +/- 4dB   20 Hz  ~ 20 kHz +/- 0.7dB
Distortion
At 10.83 VRMS output 0.4% THD
Feedback   ZERO negative feedback used
Rectification   Ultra Fast Recovery Bridge
Signal tubes   6N1P-EB
Biasing   Self-Biasing circuit - never needs adjustment
Resistors   All resistors are audiophile grade
Signal Caps   Cryo treated Copper Foil Beeswax
Filter Caps   All filter caps are premium quality
AC cord   IEC connector provided with removable power cord
Fuse
Dual Fuse holders / one per channel / external
Consumption   109 watts at full power
Input jacks   High Quality XLR 
Output jacks   High Quality XLR 
Warranty   Lifetime to original owner / 90 days on tubes


VOLTAGES

This preamplifier comes standard with our World Voltage Compatible Transformers.
It will be automatically wired for the right voltage for your country and be supplied
with the right removable power cord.



ZTPRE Distortion Analysis at full output 0.4% THD


ZTPRE Schematic of One Channel Only





OWNERS MANUAL




OWNERS-MANUAL.PDF






ZTPRE TOP VIEW




Have your ZTPRE built and shipped to your door for a
30 d
ay money-back in home trial less a 10% restock fee. 






  Z E N   T R I O D E  P R E A M P L I F I E R

   



MODEL ZTPRE

  XLR Balanced Duel Mono Line Stage


Hand Crafted in the USA and sold Factory Direct with a
 
L i f e t i m e   W a r r a n t y  !




THIS HAS BEEN REPLACED WITH ZTPREv2

FIND IT HERE