DENON DH-710F

Commentary

This is a tape deck that has all the technology to aim at a full-scale 38/2 track high performance deck.


Direct Drive 2 capstan system is adopted for the mechanism part.
The two capstan blocks the contact surface between the tape and the head from external (reel side) vibration elements to stabilize the tape running on the head surface. In addition, the DH-710F adopts a direct drive system in which the main capstan is directly connected to an AC motor, and a newly designed direct drive 2 capstan in which the motor shaft and sub-capstan are connected by a special inelastic belt.
In addition, the speed servo of the outer rotor capstan motor uses DENON's unique high-precision magnetic recording detection method to achieve excellent wow flutter characteristics.

An electronic tension servo is used for both the feed reel motor and the take-up reel motor.
By controlling the AC current flowing through the reel motor, the tape tension is kept constant not only during recording and playback but also during fast-forwarding and rewinding, regardless of the reel size or the amount of remaining tape.

The 2-capstan system and electronic tension servo improve the basic running characteristics of the wake-up characteristics and wow flutter. In addition, the tape path is shortened by making the distance between the two capstan as close as possible, eliminating the longitudinal vibration and microvibration of the tape as much as possible, and reducing noise caused by FM modulation.

The tape is designed to run straight between the left and right tape tension arms except during recording and playback, making it easy to set up the tape and eliminating the need for a tape shifter.
In addition, the parts that contact the tape other than the head use a newly designed guide roller. Since all parts are rotating bodies, stable running characteristics can be obtained even when thin tapes such as long play tapes are used.
In addition, a one way air damper is used for the left and right tension arms to prevent excessive tension at the start.

The capstan shaft is 12 mm of 12 mm according to broadcasting station standards to improve reliability. Moreover, precision processing to the limit increases roundness and hard chrome processing improves durability.


Uses Sendust alloy head developed independently for the head part.
The use of a broadcasting station head with a wide track width reduces noise, provides excellent recording and playback characteristics with little distortion, and maintains stable performance even in long-term use.
In particular, the playhead has been finished with a special shape that reduces the low-frequency bulge due to the shape effect. The shape effect is caused by the shape of the surface where the head comes into contact with the tape. However, by finishing the shape of the head so that the tape gradually separates from the head, the shape effect is minimized.


Both the microphone amplifier and the recording amplifier maintain a large margin to enable recording with a wide dynamic range.
In addition, it is equipped with a microphone attenuator so that even high-quality live sound sources can be recorded with plenty of time.


The frame precision machined aluminum casting integrated frame is used for the frame part.
This enables accurate mounting of the head system and the tape running system, suppressing mechanical distortion caused by aging and maintaining initial performance for a long period of time.

The bias amount and recording equalizer characteristics are continuously variable, and can be adjusted according to the attached tape-specific BIAS/EQ adjustment table to maximize the recording tape's capabilities.
In addition, a high-frequency recording bias (200 kHz for the DF 710 f) is used to improve the S/N ratio and prevent B when recording an FM stereo broadcast transmission.

You can easily check the reference playback level by adjusting the playback volume knob to the reference position of the long line.

Equipped with a level meter that can be switched between peak level indication and VU indication.

Remote control is possible.

Can be used horizontally and vertically.

Model Rating

Type	Tape deck
Track format	2-track 2-channel recording and playback 4-track 2-channel playback
Heads	Recording and playing : Sendust head Erasing : ferrite heads
Tape Speed	38cm/s, 19cm/s
Speed deviation	Within ± 0.5%
Motor used	For Capstan : 6 Pole Outer Rotor Type AC Servo Motor For Reel : 2 x 6-pole AC servo motors
Capstan drive system	Two capstan drive by AC servo direct drive capstan and sub-capstan
Tension servo system	Electronic tape tension servo
Wow flutter	38cm/s : 0.02% Wrms or less 19cm/s : 0.025% wrms or less
Reel Diameter Used	Maximum No. 10 (Type 26)
Quick winding time (with No. 10 reel, 740m tape)	2 minutes or less
Recording bias	Frequency : about 200 kHz Bias Amount : ± 40% Adjustable
Recording and playback compensation characteristic	NAB standard (recording guarantee can be adjusted depending on the tape used)
Overall SN ratio (hearing correction JISA)	66 dB or more for maximum recording level (514pWb/mm) 58 dB or more (for reference recording level (200pWb/mm))
Total Distortion Rate Characteristics (1 khz Reference Level)	Total harmonic distortion rate : 0.5% or less Third harmonic distortion factor (using Scotch #250) : 0.1% or less
Overall frequency characteristic	38cm/s : 30 Hz to 30 kHz ± 2 dB 19cm/s : 20 Hz to 20 kHz ± 2 dB
Channel Separation (1 kHz)	55 dB or more (2 tracks)
Input (0 dB : 0.775 V)	Mic : 0.2 mV (-72dB, Att 0 dB) / 50k Ω unbalanced Line : 62 mV (-22dB) / 100k Ω unbalanced
Power (reference power level (0 VU))	Line : 0.775 V (0 dBm) / 100 Ω or less, Applicable load : 600 Ω or more Mic : 8 Ω or more compatible
Remote control terminal	Yes
Pwer	100 VAC, 50Hz/60Hz
Power consumption	130W
External dimensions	Mechanism Part : Width 505x Height 420x Depth 310 mm (With Lid) Amplifier : Width 490x Height 180x Depth 330 mm (with lid)
Weight	Mechanism Part : 27 kg Amp : 8.5 kg
Attachment	Reel 10 x1 No. 10 Reel Clamper x2 No. 7 Reel Clamper x2 Reel Height Adjustment Sheet x2 Two parallel pin cords Socket Wrench x1 for M3