DENON PMA-350Z

Commentary

A pre-main amplifier designed for high sound quality with excellent circuit technology and a circuit configuration using highly reliable parts.

The power amplifier consists of a pure complimentary service circuit using a Darlington power transistor (Motorola, U.S.A.) of a PNP-NPN pair with high symmetry in electrical characteristics, and an OCL circuit directly connected to all stages.
As a direct couple with two power supply system and no output capacitor is used, the output impedance characteristic is low output impedance of 0.15 Ω or less up to 10 khz, so that the braking ability of the speaker does not deteriorate in the ultra low frequency range.

The Darlington power transistor combines a large radiator with excellent heat radiation effect, and is stabilized by a temperature compensation circuit, which enables stable operation even after many years of use.

The power supply section uses transformer and non-inductive high-ripple type large-capacity capacitors with excellent regulation.

The preamp section uses carefully selected high-precision parts and a high-voltage low-noise transistor to improve dynamic margin and signal-to-noise ratio. In particular, the equalizer section uses an ideal circuit constant to high-precision RIAA deviation.

The tone control circuit employs an NF-type tone control circuit that uses an FET with good noise figure for the intermediate amplifier stage. This realizes excellent linearity characteristics in a flat position. In addition, the tone control circuit uses a special volume to obtain sound quality variation characteristics according to listening conditions. This volume is an 11-position click-stop type.

Two tape decks can be connected, and a tape monitor and dubbing switch are mounted.

Equipped with low filter and high filter.

Equipped with audio muting.

Equipped with a loudness control.

Model Rating

Type	Pre-main amplifier
Power Amplifier Unit
Music power	70W (8 Ω)
Rated Output (THD 0.1% or less)	31W/31W (8 Ω, single-channel drive) 27W + 27W (8 Ω, when driving both channels)
Total harmonic distortion factor	0.1% or Less (at Rated Output)
Cross modulation distortion factor	0.1% or Less (60Hz/7kHz = 4/1)
Output bandwidth	30 Hz ~ 30 kHz + 0 -1dB (THD 0.1%)
Frequency characteristic	8 Hz to 150 kHz ± 0.5 dB
Input impedance	90k Ω ± 10%
Input sensitivity	1Vrms/90k Ω (at rated output)
Residual noise	0.5 mVrms or Less (Input Terminal Short Circuit)
Output impedance	0.15 Ω or less
Preamplifier Section
Maximum power output	4 Vrms or more
Total harmonic distortion factor	0.1% or Less (Maximum Output) 0.08% or Less (at Rated Output)
Rated output	1Vrms
Input Sensitivity / Impedance (20 Hz to 20 kHz)	Phono1/2 : 2mVrms/60k Ω ± 20% Tuner, Aux : 100mVrms/100k Ω ± 20% Tape PB : 320mVrms/100k Ω ± 20%
Maximum allowable input	Phono1/2:40mVrms(100Hz) 180mVrms(1kHz) 600mVrms(10kHz)
RIAA deviation	Within ± 0.5 dB (30 Hz to 15 kHz)
Signal-to-noise ratio	Phono1/2 : 62 dB or more Tuner, Aux, Tape : 73 dB or more
Audio Muting	-20dB
Tone control	Bass : + 10 dB ~ -10.5 dB (80 Hz) Treble : + 10 dB ~ -9dB (12 kHz)
High filter	9 kHz, 12dB/oct.
Low filter	40 Hz, 12dB/oct.
Recording Output / Impedance	Tape rec : 100mVrms/1k Ω or less
<General>
Semiconductor used	NPN type transistor : 15 pieces PNP transistor : 4 pcs FET : 2 Diode : 10 pcs Varistor : 2 pieces
AC outlet	Switched : 2 systems, 250W Unswitched : 1 line, 150W
Pwer	100 VAC, 50Hz/60Hz
Power consumption	60W (Electrical Appliance and Material Control Law)
External dimensions	Width 430x Height 140x Depth 350 mm
Weight	10.5kg