Akai 4000DB Service Manual

Specifications and Main Features

Track Arrangement: This system is designed for feedback matrix systems, which will consist of four tracks and feature a Stereo channel output.
Maximum Reel Size: This device can handle reels measuring up to 7 inches.
Speeds Supported: The two supported speeds are 7 1/2 inches per second and 3 3/4 inches per second (+2% (+3%)).

WOW and Flutter:

The Roughness Factor Metric is less than 0.15% (0.22%) at a pace of 7-1/2 inches per second.
The Roughness Factor Metric is less than 0.2% (0.3%) at a pace of 3 3/4 inches per second.

Total WOW and Flutter: The combined total of WOW and flutter is less than 0.28% measured at a pace of 7-1/2 inches per second, and a range of 3,000 hertz for both recording and playback.

Frequency Range/ Bandwidth:

Extended (AKAI SRT TAPE): Between 30hz to 23,000hz, measured with an increase of +3dB and a pace of 7 1/2 inches per second.

Low Noise (SCOTCH #211 TAPE): Between 30hertz to 16Khz, with an increase of +3dB and a pace of 3 3/4 inches per second.

Degree of Distortion: At a frequency of 1000 Hz OVU the spread of distortion metric is not more than 1 percent.

Complete Cross-Distortion Level: At levels of 7 1/2 and 3 3/4 inches per second the frequency of distortion spread should not exceed 1.5 percent.

Playback Output Level:

Line Output: 0.775V (0 dBm +1.0 dB).

DIN Output: 0.5V.

Headphone Output: 30 mV with 8Ω.

Inputs:

MIC INPUT: > 0.4 mV.

LINE INPUT: > 70 mV.

DIN INPUT: >2.5 mV (low), 75 mV (high).

Recording/Playback Level:

Wide Range: 0 + 0.5 dB (with 1 kHz recording of OVU at level + 02)

Low Noise: 0 + 1.0 dB (with 1 kHz recording of OVU at level + 02)

Signal to Noise Ratio: Better than 55 dB (50 dB)
Total Signal to Noise Ratio: Better than 45 dB
Cross Talk:
Better than 65 dB (*60 dB) (mono)
Better than 40 dB (stereo)
Erase Ratio: Better than 70 dB
Recording Bias Frequency: 105 kHz with tolerance of plus 5%.
Bias Leak: Better than —25 VU
High Frequency Deviation: Within 2 dB
Recording Capacity: 90 min of stereo recording on 1800 ft tape at 7.5 ips.
Fast Forward and Rewind Time: 4 min 40 sec for fast forward and 3 min 40 sec for rewind.
Motor: This includes a four pole Induction 1-speed motor, model SSM-1, with a rotary frequency of 1500/1800 revolutions per minute. The voltage powering this motor has its frequency at 50/60 Hz.
Heads:
Erase Head: Type: E4-200; Gap: 0.6 mm
Recording Head: Type: P4-154; Gap: 1 micron
Playback Head: Type: P4-150; Gap: 1 micron
Dimensions: 406(W) x 325(H) x 196(D) mm (16.0’’ x 12.8’’ x 7.7’’)
Weight: The entire weight of the unit is 12 kilograms which is equal to 26.4 pounds
Power Supply: The AC power supply required for Universal models is 100 to 240V, 50 or 60 Hertz. The power input for CSA or UL models is 120 volts 60 hertz. And, 220 Volts A.C 50 hertz are required for the CEE models.
Power Consumption: The device consumes approximately 40 watts of energy.