Audio Database


NEC AV-300typeII
89,800yen(around the 1986 time)

audio-video surround center which carries a digital delay.

The digital delay is carried and the extensive modification of a property is realized by carrying out the A/D conversion of the analog signal once, and digitizing and controlling it.
A 16-bit linear-line successive-approximation-type analog-to-digital converter, 16 KbitS-RAM, and an IC for an address control are consisted of by this circuitry, and the delay time of 15/20/30msec can be set to it.

As surround mode, the three modes, Dolby surround, hole surround, and matrix surround, are carried.
Dolby surround has acquired the surround intelligence by applying a delicate time delay to the difference signal added to 2usual ch signals (L-R). Moreover, in hole surround, the front speaker is being reproduced from the usual stereophonic reproduction and a back surround speaker, applying an echo to the composite signaling supposing a concert hall of reflective sound (L+R).
In matrix surround, 2ch signals which mixed a little signal on either side are reproduced from a front. From rear , the signal which added the negative phase component of opposite ch conversely is reproduced.

The surround indicator which can check at a glance what has happened to the present surround control status is carried.
It is also possible to turn OFF when unnecessary.

At the time of a hole surround play, it is possible to adjust the amount of echoes of surround according to liking.

the full mute switchpoint is carried and all the sound is stopped at a stretch -- things can be carried out.

4 mode balance volume in which, as for the master volume which can control the volume of all the channels simultaneously, the 2ch/rear 2 ch/R side can control 2ch, and the 2 ch/L side can control a front is carried. Moreover, three kinds of volumes of each channel independent volume are carried.

The synthesizer tick stereo functionality is carried and a monophonic signal can be done in a stereo in false by letting a digital-signal-processing circuitry pass.

The it1 position is carried. (to sake when surround is unnecessary)

The tone control which can adjust a front and each rear tone quality is carried.

The image enhancer which rectifies the outline of an indistinct image and reproduces a clearer image is built in.
The change of a two-step of 3dB and 6dB is possible for the amount of enhancing.

Independent power amplifier is carried 4 ch.
The using as 2ch amplifier is also possible for this amplifier by the BTL interconnection.

The wireless remote control in which the change of each surround, a delay time selection, and a volume coordination of each ch are possible is attached.
With this remote control, a surround position, a volume, delay time, etc. are memorizable to three kinds with a memory functionality.


Rating of a mode
Form audio-video surround center
<Amplifier part>
Effective output (1kHz, 5%, 6ohm) 50Wx4
100W+100W (at the time of BTL)
THD 0.03% (at the time of 20W output)
SN ratio Main in:100dB
Input unit Voice: Mono-[ three stereos, / two ]
Image: Four lines
Input sensitivity/impedance Voice input: 150mV / 47kohm
Video input: 1 Vp-p/75ohm
<Processor part>
Surround synopsis Dolby surround
Hole surround
Matrix surround
Latency scheme 16-bit linear-line quatization (digital)
Delay time 15, 20, 30msec
Power consumption 165W
The maximum Dimensions Width 430x height 110x depth of 340mm
Width 430x height 122x depth of 359mm (maxima)
Weight 9.5kg
Adjunct Wireless remote control AR-301