McIntosh MA230

1963-1966

Hybrid (solid state preamp and tube power amplifier). 30w/ch stereo, 60w mono. Response 20-20kHz (+0 -0.5dB). Distortion 0.5%. Noise and hum -75dB high level, -60dB low level . Output impedance 4, 8 and 16 ohms. Damping factor 10. Input sensitivity and impedance: high level 0.25V at 250k, phono 1.5mV at 47k, tape head 1.5mV at 1 meg. Tape output 0.25V into 25k. L+R output 10V into 5k. Dual concentric tone controls +18dB to -18dB. LF filter 50Hz at 12dB/oct. HF filter 5k at 12dB/oct.

FRONT PANEL: Glass panel at top. Anodized gold at bottom. Input selector: aux, tape, tuner, phono 1, phono 2 and tape hd. Bass and treble each dual concentric. Volume. Mode selector: L to L+R, R to L+R, stereo rev, stereo, mono (L+R), L+R to L and L+R to R. Balance. Rocker switches: comp: RIAA or LP, tape monitor, phase: 0 or 180, speaker: on or off, power: on or off, LF: flat or filter, HF: flat or filter, loudness: flat or compensate. Headphone jacks. Red power indicator.

BACK PANEL: Barrier strips for 4, 8, and 16 ohms, Outputs: Tape and L+R. High level inputs: tape mon, aux, tape and tuner. Low level inputs: ph 1, ph 2 and tape hd. Ground binding post. AC outlets: 2 switched, 1 unswitched. Fuse.

TUBES: 4-7591, 2-12AU7, 12AX7.

Size 5-7/16\"H, 16\"W and 14-1/2\"D. Weight 43 lbs