The AV- is Nakamichis most powerful audio/video receiver. It contains an AM/FM digital frequency-synthesis tuner a preamplifier digital signal processing (DSP) circuits for simulating several acoustic environments and five power amplifiers. The AV-1 has complete signal-switching facilities for selecting and controlling tuner CD and phono sources two audio tape decks two VCRs and a videodisc player including inputs and outputs for both composite-video and S-video signals.

The front (main) power amplifiers are rated at 100 watts per channel into 8 ohms from 20 Hz to 20 kHz both channels driven with less than 0.1 percent total harmonic distortion (THD). A switch on the rear of the receiver enables safe full-power operation into 4-ohm loads. The surround-channel amplifiers are rated at 30 watts apiece and the center-channel amplifier is rated at 50 watts all at 1 kHz into 8 ohms with no more than 0.1 percent THD.

The AV-1s large front-panel volume knob is driven by a motor when operated from the supplied remote control. The receivers only other control knob is a small input-balance adjustment for setting up the Dolby Pro Logic decoder. All other operations including station selection audio level tone-control adjustment and the like are done with pushbuttons.

The AV-1s front-panel display window shows its complete operating status. The tuned frequency preset channel number and station call letters (when programmed by the user) appear in large orange characters against a black background. Smaller red or orange characters show the signal-processing mode tuner status and relative signal strength and tape (audio and video) source and dubbing path where applicable.

Below the window a row of large pushbuttons selects the program source and dubbing configuration. The Source Direct button bypasses all surround and response-modifying circuits routing the selected program through the volume control and directly to the front-channel power-amplifier sections.

Below the source selectors a group of smaller buttons controls the receivers four spatial-modification circuits. These include Dolby Pro Logic for compatibly encoded video or audio programs and three synthesized environments identified as Natural Hall and Stadium. The Hall environment simulates the effect of a typical concert hall by adding reverberation to the delayed signals supplied to the surround speakers. Stadium provides longer delays and more reverberation whereas Natural (for use with programs containing considerable reverberation) adds mainly an array of discrete signal delays rather than reverberation.

Other buttons control the Surround Memory function which enables the user to program a�� store as many as four different sets of spatial parameters for later recall. This is done with the previously mentioned spatial-modifier buttons which are also numbered 1 through 4. In addition to its normal function each button can be used to store one set of user-selected parameters retrievable by pressing the Memory Call button. The adjustable parameters include the level of each channel delay time (from 10 to as much as 150 or 250 milliseconds except for the Pro Logic mode which is limited by Dolby specification to a range of 15 to 30 milliseconds) and tone-control settings.

The tone-control level and delay adjustments are performed with a single pair of up/down buttons and a group of small selector buttons marked Center Level Rear Level Delay Balance Treble Bass and Super Bass. The up/down buttons adjust the value of a selected function in ten steps for each of the tone controls and nine steps for the full range of the balance adjustment. The delay can be adjusted in 10-millisecond intervals. The treble and bass tone-control ranges are typical of modern receivers but the Super Bass feature is unusual and convenient cutting in about an octave lower than the main bass control. A small loudness-compensation button is located near the volume knob.

Other front-panel features include the tuning buttons small adjacent buttons that select AM or FM and automatic stereo switching with interstation muting or mono FM reception without muting for weak signal reception. A grid of small buttons is used for storing as many as thirty AM or FM channel presets or for direct numerical tuning to any frequency. These buttons can also be used to add your own five-digit alphanumeric identifier to each preset memory which will be displayed when that preset is selected. At the lower left of the panel are a stereo headphone jack separate speaker-switching buttons for two pairs of front speakers and the surround and center speakers and the input-balance knob for the Dolby Pro Logic decoder.

The AV-1s rear apron contains input and output jacks for all potential source components and recorders plus composite- and S-video monitor outputs. There is also a separate preamplifier output and power-amplifier input (joined by a removable