JVC AX-Z1010TN amplifier

Digital Pure-A. New possibilities for class-A

There's no doubt an amplifier operating in class-A mode provides lower distortion and cleaner sound than those in popular class-B or class-AB. Their inefficiency, however, makes class-A amplifiers require elaborate heat sinking, and still the amps waste much of their power in the form of heat. This results in inflated cost and relatively low power output. But to enjoy the dynamic sound of digital programs, you need a lot of power.

How to combine the low-distortion sound of class-A with efficiency and power demended by digital audio?

Enter the Digital Pure-A Type II

JVC has the solution - the Digital Pure-A Type II circuit featured in the Ax-Z1010TN "Digital" Integrated Amplifier. This ingenious design takes the advantage of the fact that digital signals can be stored in memory temporarily without changing their frequency response or phase response.

In the Digital Pure-A Type II, digital signals fed directly from digital equipment are split into two: the main signal and the "prediction" signal.

The main signal is sent to a time base processor where it's stored in memory for a fraction of a second before it goes to the D/A converter. The prediction signal is sent to the bias circuit to optimize bias applied to the power transistors depending on dynamics of the upcoming signal. What you get out of this is low-distortion class-A sound with high efficiency and high power.

The AX-Z1010TN is a "Digital" integrated amplifier incorporating a D/A converter system complete with the K2 interface, 8-times oversampling and quadruple D/A converters.

And the amp features a special design for analog programs too - Opt Super-A, another JVC exclusive combining low distortion and high efficiency.

 

Specifications

Circuitry

Preamplifier:  ICL, MC/MM equalizer with EL-FETs in its initial stage

Power Amplifier: "Digital Pure A Type II", "Dynamic Super-A" with Gm circuit

Output Power

105 watts per channel, min. RMS, both channels driven into 8 Ω  from 20 Hz to 20 kHz, with no more than 0,004% Total Harmonic Distortion (USA, Canada)

100 watts per channel, min. RMS, both channels driven into 8 Ω  at 1 kHz, with no more than 0,002% Total Harmonic Distortion (Europe, UK, Australia)

100 watts per channel, min. RMS, both channels driven into 8 Ω  at 1 kHz, with no more than 0,7% Total Harmonic Distortion DIN  (Europe, UK, Australia)

160 watts 1 kHz, 4 Ω , T.H.D. 0,7% DIN

Total Harmonic Distortion (USA, Canada)

CD IN to SP. OUT :  0,004% (20 Hz - 20 kHz, 8 Ω ) at 100 watts

Phono IN to SP. OUT (Volume -20 dB) :  0,009% (20 Hz - 20 kHz, 8 Ω ) at 100 watts

Total Harmonic Distortion (Europe, UK, Australia)

CD IN to SP. OUT :  0,004% (20 Hz - 20 kHz, 8 Ω ) at 90 watts

Phono IN to SP. OUT (Volume -20 dB) :  0,009% (20 Hz - 20 kHz, 8 Ω ) at 90 watts

Intermodulation DIstortion (USA, Canada)

CD IN to SP. OUT :  0,004% (60 Hz : 7 kHz = 4:1, 8 Ω ) at 100 watts

Intermodulation DIstortion (Europe, UK, Australia)

CD IN to SP. OUT :  0,004% (60 Hz : 7 kHz = 4:1, 8 Ω ) at 90 watts

Power Bandwidth

CD IN to SP OUT :  5 Hz - 60 kHz (IHF, 0,03%, 8 Ω  both channels driven)

Frequency Response:  5 Hz - 100 kHz +0 dB -3 dB (8 Ω )

Damping Factor:  200 (1 kHz, 8 Ω )

Input Sensitivity/Impedance

Phono MM :  4 mV/47 k Ω

Phono MC :  300 µV/470 Ω

CD, Line1, 2, 3, DAT 1, 2, Tape 1, 2 :  300 mV/30 k Ω

Signal-to-Noise Ratio )'66 IHF/DIN)

Phono MM :  89 dB / 73 dB

Phono MC :  71 dB

CD, Line1, 2, 3, DAT 1, 2, Tape 1, 2 :  112 dB / 73 dB

Signal-to-Noise Ratio )'78 IHF)

Phono MM :  82 dB (Rec Out)

Phono MC :  73 dB (Rec Out)

CD, Line1, 2, 3, DAT 1, 2, Tape 1, 2 :  86 dB / (Speaker Out)

Bass Control:  0 - +5 dB (50 Hz, Master Level -30 dB)

Recording Output

Output Level/Impedance : 

Analog :  300 mV/ 1 k Ω

Digital :  2,0 V/ 1 k Ω

Digital Input/Output

Digital 1 :  -23 - -14 dBm

Digital 2 :  0,5 Vp=p/75 Ω

DAT Rec :  0,5 Vp-p/75 Ω

DAT Play :  0,5 Vp-p/75 Ω

D/A Converter Section

Sampling Frequencies :  32 kHz; 44,1 kHz; 48 kHz (Auto Selection)

Total Harmonic Distortion (1 kHz):  98 dB

Signal-to-Noise Ratio :  107 dB

Equalizer

Phono Overload Capacity

Phono MM :  100 mV (1 kHz, 0,02% T.H.D.)

Phono MC :  7 mV (1 kHz, 0,03%, T.H.D.)

Phono RIAA deviation:  ±0,2 dB (20 Hz - 20 kHz)

Power Requirements:  AC 120 V , 60 Hz (USA) AC 110, 127, 220, 240 V , 50/60 Hz  (Other areas)

Power Consumption:  550 watts/ 720 VA (USA); 400 watts (other areas)

Dimwnsions (W x H x D):  435 x 173 x 459 mm (17-3/16" x 6-13/16" x 18-1/8")

Weight:  16,8 kg (38 lbs)