Ideal Balance of "Delicate Sound Nuances" and "High Output Power" Achieved by UHC Single Push-Pull Circuit
The ability to bring out the delicate nuances of sound even during passages of dynamic fortissimos is the envy of every amp. With the PMA-S1, however, that envy has finally become a satisfying reality, thanks to DENONﾕs newly-developed UHC Single Push-Pull circuit. This technology is the same as that used in the high-end POA-S1 monaural power amp.
The Operation of Conventional Amplifier Devices and Output Circuits
At present, there are mainly two types of amplifier devices: bipolar transistors and MOS-FETs. Bipolar transistors are adept at delivering high output power but the sound quality of low-level signals leaves much to be desired. MOS-FETs, on the other hand, reproduce a smooth, supple sound from low-level signals but suffer from inefficient production of current needed to drive the speakers, resulting in a lack of dynamism in the overall sound. The challenge, therefore, has been to combine the merits of both devices.
The power amp stage of most integrated amps today employ a parallel push-pull circuit in which multiple numbers of amplification devices are connected. This Multi Parallel Push-Pull design improved current supply capabilities. However, due to the tolerance among the many devices and the increased complexity of the signal path, it failed to sufficiently remove annoying distortion in the sound reproduced from low-level signals.
UHC-MOS High-Current Amplification Device
The UHC-MOS is the ideal element that boasts both the sound quality merits of conventional MOS-FETs and the high power of bipolar transistors. It successfully meets the challenge to reproduce high sound quality even from low-level signals while providing ample current to drive the speakers.
The positive merits of the UHC-MOS are reinforced with Cascode Bootstrap technology to produce a dramatically improved linearity. This added refinement ensures that the sound from the speakers is full of lively details amply supported by a solid foundation that is capable of handling all possible musical events, including sudden shifts from delicate lows to grandiose highs.
Simple, Straightforward Design for the Amplification Stage
Superior sound quality is always a direct result of a simple, straightforward amplifier design. The Cascode Bootstrap technology used in the PMA-S1 not only improves linearity but also provides an ideal load for the power amplification stage, achieving a simple, straightforward design of two voltage amplification stages and one power amplification stage. The superior basic characteristics of the PMA-S1ﾕs UHC-MOS are thus able to realize their maximum potential and reproduce a truly natural, musical sound that is always a refreshing auditory treat.
BTL Circuit, to Protect Clarity of Musical Signals
The PMA-S1 incorporates a Balanced Trans-Less (BTL) circuit capable of attaining stable output at low power voltage levels and enabling the use of low-voltage transistors designed for high-quality sound. In addition, the ground circuit has been separated from the output current destined for the speakers to further protect the purity of the output signal. The audible result is superior sound imaging that masterfully reflects the sort of acoustic experience one would expect at a large concert hall.
Single-Body Chassis Made of Vibration-Resistant Sand-Cast Material
The radiator and chassis of the PMA-S1 have been forged into an extremely sturdy single body made of a non-magnetic sand-cast material that rapidly dampens vibrations from the transformer and other sources both inside and outside the unit. A vibration-free environment ensures that musical signals are amplified and flow without distortion to the speaker terminals. In addition, the transformer core and insulators made of a sintered metal alloy are mounted directly onto the chassis to further reduce the negative influences of vibrations. The clarity of sound resulting from this ideal vibration-free integrated amp construction is a wonder that heralds repeated listening satisfaction.
New Inverted SIGMA Balance Circuit
Balanced transmission is a vital feature in today's high-end audio equipment, since the preservation of musical signal purity during transmission is absolutely essential to the success of overall performance. The PMA-S1 is endowed with the New Inverted SIGMA Balance circuit, newly-developed by DENON, which works for both balanced and normal inputs. This circuit does away with the need for separate conversion circuits in the input and voltage amplification stages, as the signal is input directly to the BTL balanced power amp. The preamp and power amp sections thus work more closely in realizing the ideal design for an integrated amp, namely simple, straightforward amplification of the musical signal.
Total Separation of the Equalizer Amp for Analog Audio
The equalizer amp of the PMA-S1 employs a dedicated two-stage constant voltage power supply. When PHONO input is not used, turning off the EQ POWER switch will cut off the circuits and power supply so that they do not adversely influence signal input from a CD or other high-quality digital sound source.
8 Sets of Input Terminals
The PMA-S1 is equipped with a versatile array of 8 input terminals: PHONO (MM), TUNER, CD, AUX-1, AUX-2, TAPE-1, TAPE-2, and BALANCED. Two sets of REC OUT terminals are also provided for TAPE-1 and TAPE-2.
Total Adherence to the"Simple, Straightforward" Principle
The PMA-S1 has sacrificed such conventional sound influencing features as Pre Out and Main In terminals, tone controls, loudness and muting buttons, filters, and headphone jacks in order to retain total fidelity to the "Simple, Straightforward" signal path principle of super-high-end DENON S1 components.
Dimensions : 434 (W) x 155 (H) x 493 (D) mm
Weight : 25 kg
Power Amplifier Section
Rated Output Power (Both channels driven): 100 W + 100W (4 ohms Continuous 1 kHz T.H.D. 0.7%) /
50 W + 50 W (8 ohms, 20 Hz -20 kHz T.H.D. 0.07%)
Dynamic Power: 120 W + 120 W (4 ohms) / 200 W + 200 W (2 ohms)
Total Harmonic Distortion: 0.007% (-3 dB at rated output, 8 ohms)
Power Band Width: 5 Hz - 50 kHz (8 ohms, T.H.D. 0.1%)
Frequency Response: 1 Hz - 150 kHz + 0 dB, -3 dB (at 1 W)
Output Impedance: 0.1 ohm (1 kHz)
Input Sensitivity/ Impedance: PHONO MM : 2.5 mV/ 47 kohms, CD TUNER AUX TAPE1, 2 : 150mV/ 47 kohms
Balanced: 150 mV/ 100 kohms
Max. Input Level: PHONO MM: 150mV/ 1 kHz
Max. Output/ Rated Output: 10 V/ 150 mV
RIAA Deviation: 20 Hz - 20 kHz ｱ 0.3 dB
Total Harmonic Distortion: 0.002% (1 kHz, 5 V output)
S/N Ratio (A-weighted)
PHONO MM: 91 dB (at 5 mV input) / CD TUNER AUX TAPE 1, 2 : 108 dB
Operation manual, warranty, AC power adapter
Special order item only. This product is usually shipped within 7-10 days.
Free heavy duty max 1000W voltage transformer to convert electricity in destination country (110~120V or 220~240V) to 100V.
Colors available: Champagne Gold