DENON DR-650

Commentary

A cassette deck developed by inheriting the performance of DR 750.

By adopting a precision machined aluminum casting frame for the mechanism part, the tape running system is stabilized.

The drive mechanism adopts the direct detection speed servo 2 capstan system.
In this method, the rotational speed of the capstan is directly detected by the magnetic head which detects 500 pulses magnetically recorded with high precision on the outer circumference of the flywheel of the main capstan shaft, and the drive motor is controlled so that the rotational speed of the main capstan becomes constant.
In addition, a non-elastic belt that does not expand or contract is used for the belt that connects the motor and the flywheel. This design prevents resonance between the belt and the flywheel and uneven tension between the left and right capstan caused by uneven belt thickness.
In addition, since the two capstan system is adopted, vibration generated in the half is cut off by both capstan, and the effect on the head surface is reduced.

The head uses a 3-laminate type Sendust head that has a large saturation magnetic flux density and does not cause magnetic saturation even for large input signals during recording.

In addition to the use of carefully selected low-noise transistors for the playback equalizer amplifier, we have also selected low-noise components in consideration of sound quality for the circuit components. In addition, by adopting a 3-stage direct-coupled configuration, the circuit has a high SN ratio and stable operation.
The recording amplifier uses a circuit with a wide dynamic range and low distortion to improve the frequency characteristics of recording and playback.

A gold-plated relay with twin contacts is used for recording and re-switching of the amplifier to prevent noise generation during switching and improve reliability and durability.

Large-size complimentary service ICs are used for the line amplifier, and sufficient power level and low output impedance are obtained.

Equipped with Dolby NR as a noise reduction system.

An IC regulator is used for the power supply, and stability is enhanced by separating the drive system, control system, and amplifier system from the secondary winding of the transformer.

Equipped with continuously variable bias and tape selector.

Equipped with a recording mute mechanism.

Equipped with a timer standby mechanism.

Equipped with a peak level meter.

Equipped with a remote control terminal and can be connected to the separately sold remote controller RC-50.

Model Rating

Type	Cassette deck
Track format	4-track, 2-channel
Heads	Recording : Sendust head Erasing : ferrite heads
Motor used	Capstan : DC servo motors For Quick Winding : DC Governor Motor
Tape Speed	4.8cm/sec
Speed deviation	Within ± 0.5%
Wow / flutter (JIS)	0.05% WRMS or less Not more than 0.12% RMS
Fast-forward and rewind time	Approximately 80 seconds (with C-60 tape)
Recording bias	Approximately 100 kHz (The bias amount can be adjusted by + 5 ~ 35% with respect to the position of the cobalt-based tape)
Overall signal-to-noise ratio	65 dB or More (CCIR/ARM, Dolby NRon, Cobalt Tape, 1 kHz, 3% THD)
Total third harmonic distortion factor	1.0% or Less (LH Tape, 1 khz, 0 db (200pwb/mm))
Overall frequency characteristic	Cobalt-based tape : 30 Hz to 18 kHz ± 3 dB LH Tape : 30 Hz ~ 16 kHz ± 3 dB
Channel separation	40 dB or More (1 kHz)
Crosstalk	65 dB or More (1 kHz)
Input	Line : -20dB/50k Ω Mic : -70dB/50k Ω * 0 db = 0.775 v
Output	Line : 0 dB (maximum output volume at 0.775 V, 10k Ω load) Headset : 15mW/8 Ω or more compatible
Pwer	100 VAC, 50Hz/60Hz
Power consumption	40W
External dimensions	Width 434x Height 185x Depth 285 mm
Weight	11kg
Sold Separately	Remote Controller RC-50 (¥ 12,000)