YAMAHA K-650
¥ 64,800 (around 1987)
Commentary
Reverse deck equipped with Dolby HX Pro and 2-mode timer.
Equipped with 2 mode timer which can select 2 types : ONCE which operates once at set time and EVERY which operates at the same time every day once set.
An amorphous head with a 12-sheet laminated structure is used for the recording / reproducing head.
Amorphous materials have characteristics such as high resistivity and low magnetic loss due to non-crystalline materials, low sound distortion due to high permeability and high saturation magnetic flux density, and excellent wear resistance. Eddy current loss is reduced by using 12-sheet laminated structure of amorphous materials.
In addition, OFC wire is used for the winding and low impedance (320 Ω, 1 kHz) is used, so that high frequency characteristics and sources with wide dynamic range can be used.
A Dolby B/C is installed as a noise reduction system.
Equipped with Dolby HX-PRO which prevents degradation of characteristics by automatically adjusting bias.
The Dolby HX-PRO operates so that the dynamic bias is constant, greatly reducing changes in frequency characteristics due to sensitivity changes. In addition, the operation is completely independent on the left and right sides, and each side is provided with optimal bias servo.
Dolby HX Pro operates only when recording, so recorded tapes can be played on other decks.
By using a ± power supply with a tracking regulator, the power supply current does not flow into the ground line, preventing excess noise from entering the signal system.
Yamaha's original pure current dam system is used in the reproduction amplifier section.
The pure current dam is a system in which a constant current is always supplied from the power supply to the amplifier. Therefore, the signal current does not flow into the ground line or power supply line, and a clean power supply current can be obtained. As a result, the power supply current is not adversely affected by non-linears which inevitably exist in the ground line or power supply line or non-linears inside the power supply.
In addition, a low-noise operational amplifier is used for the recording amplifier, and a ± power supply is used to enable recording with a wide dynamic range.
The mechanism uses a 2 + 1 motor separate drive system.
With the 2-mode rememing time display, you can display the remaining amount of tape from the unrecorded portion or from any position.
Equipped with an auto fade in / out feature that automatically fades out at the end of the tape and automatically fades in immediately after a quick reverse.
Equipped with auto fader which can fade in / out with one touch operation.
It is equipped with an intro-scan function that plays the head of a song one after another for 15 seconds.
It is equipped with a blank screen function that automatically fast-forwards to the next song when there is a blank of more than 15 seconds.
Equipped with a memory stop function to stop after fast forward and rewind to the set position.
It is equipped with a repeat function that can repeat up to 8 times between counter 0 and memory counter.
Equipped with a maintenance monitor function to automatically accumulate and display the usage time of the head (display up to 40 hours).
Equipped with 2-color 12-segment peak level meter.
Model Rating
| Type | Cassette deck |
| Tape rerecording system | Auto-reverse stereo |
| Heads | Recording : Amorphous Erasing : double-gap ferrite Integrated Recording / Reproducing / Erasing Mounted Rotary Type |
| Motor | For Capstan : DC Servo Motor For Reel : Flat Torque DC Motor For Assist : DC Motor |
| Wow flutter | 0.05% or Less (JIS, W. RMS) |
| Signal-to-noise ratio | 72 dB (Dolby C on) |
| Frequency characteristic | 20 Hz ~ 17 kHz ± 3 dB (normal) 20 Hz ~ 19 kHz ± 3 dB (Chrome) 20 Hz ~ 20 kHz ± 3 dB (metal) |
| Overall strain rate | 1% |
| Channel separation | 40dB |
| Meter | 2-color 12-segment peak level meter (-20dB to + 12 dB) |
| Input Sensitivity / Impedance | Line : 50mV/47k Ω Mic : 0.3mV/5k Ω |
| Output Level / Impedance | Line : 360mV/1.5k Ω Headphone : 0.3mW/8 Ω |
| Power consumption | 18W |
| External dimensions | Width 435x Height 114x Depth 303 mm |
| Weight | 5.2kg |