Audio Research D-90

Audio Research D-90

Tube power stereo ampli

Specifications

Power output : 90 watts per cannel minimum continuous (both channels operating) at 16 ohms from 25 Hz to 20 kHz .

Approximate power available per channel at "clipping" (Both channels operating, 1kHz): 105 watts

Total harmonic distortion (THD) : typically below .01% at 1 watt.

Intermodulation distortion : Less than .5% at 1 dB below rated output (100V p to p, 16 ohms) (SMPTE method)

Power bandwidth (-3dB points) : 12 Hz and 60kHz

Input sensitivity : 1.2V RMS for rated output (adjustable)

Input impedance : 75 kOhms, nominal at maximum gain

Output regulation : approximately .8dB, 16 ohm load to open circuit

Overall negative feedback : 17.5 dB

Damping factor * : approximately 12

Slew rate ** : 20 V/µs

Rise time *** : 2.5 µs

Hum & noise wideband, unweighted, more than 90dB below rated output

Line components, more than 80dB below rated output

Power supply energy storage 240 joules total

Power requirements 105-125VAC 60 Hz (210-250VAC 50 Hz) 800 watts maximum. 400 watts at "idle". 500 watts at rated power.

Years of construction : 1980 – 1985

Models : D-90 , D-90 revisited, D-90 B

* the ratio of the rated impedance of the loudspeaker to the source impedance.

( Il rapporto tra impedenza dell'altoparlante e impedenza del segnale di ingresso)

** the maximum rate of change of the output voltage for all possible input signals.

(Il massimo tasso di variazione nel tempo del segnale di uscita per tutti i possibili segnali d'ingresso)

*** it refers to the time required for a signal to change from a specified low value to a specified high value.

(Il tempo richiesto dal segnale per aumentare da un determinato basso valore ad un determinato alto valore)

Tubes

D-90: (4) 12AX7, (2) 6FQ7, (2) 12AT7 (4 matched pairs) 6550, (1) 6550

D-90 Revised: (4) 12AX7, (2) 6FQ7, (2) 12AT7, (4 matched pairs) 5881, (1) 6550

D-90B: (1) 12AX7, (5) 6922, (4 matched pairs) 5881, (1) 12BH7, (1) 12AT7

Dimensions

19" (48 cm) W (standard rack panel) x 7" (18 cm) H x 16.5" (42 cm) D (front panel back). Handles extend 1 5/8" (4.1 cm) forward of front panel

Weight 64 lbs. (29 kg) Net, 80 lbs. (36.3 kg) Shipping

Are available on request schematics and parts list.

Sono disponibili a richiesta gli schemi e la lista dei componenti.