Vintage

Aiwa’s compact SA-C30 preamplifier offers a useful +14.9dB maximum gain via its Aux inputs and a very generous maximum output of 10V. Unfortunately the output impedance is a high 3kohm so the SA-C30 may show some sensitivity to long or ‘exotic’ interconnects, as unlikely a pairing as this might seem! The response is flat from –0.02dB/20Hz to –0.2dB/20kHz and has very extended ±1dB limits of 2Hz-52kHz although channel separation is really only good to 50dB up to 1kHz and 31dB to 20kHz. Distortion is low at ~0.0012% (re. 1kHz/0dBV) but increases quite steeply above 10kHz to reach 0.008%/20kHz [black trace, Graph 2 below], but these are fine ‘vintage’ figures. The partnering SA-P30 power amp was rated at 35W/8ohm in its day, but achieved rather more on the bench at 2x45W/ 8ohm and 2x65W/4ohm, with sufficient in reserve to support 63W, 98W, 64W and 40W into 8, 4, 2 and 1ohm loads under dynamic conditions [all via the 8ohm setting, see Graph 1].

This is also a wide bandwidth/low noise design with a response that stretches out from 1Hz-50kHz within –0.5dB limits (and to 100kHz at –1.1dB) while enjoying a very wide A-wtd S/N ratio of 98.5dB (re. 0dBW). The output impedance is modest at ~0.06ohm from 20Hz-3kHz before lifting slightly to 0.1ohm/20kHz, so the SA-P30’s very flat response will be only mildly influenced by the varying impedance trend of the attached loudspeaker. Distortion increases gently with power output, from 0.006% (1-10W) to 0.07% at the rated 35W/8ohm (all re. 1kHz), and with frequency to 0.035%/10kHz and 0.05%/20kHz [red trace, Graph 2]. However, as with the SA-C30, stereo separation is weak by modern standards at ~45dB midband. PM

Hi-Fi News Measured Specifications:

Power output (<1% THD, 8/4ohm)	45W / 65W
Dynamic power (<1% THD, 8/4/2/1ohm)	63W / 98W / 64W / 40W
Output imp. (20Hz–20kHz, pre/power)	2.9-3.0kohm / 0.061-0.125ohm
Freq. resp. (20Hz–100kHz, pre/power)	+0.0 to –3.1dB / +0.0 to –1.10dB
Input sensitivity (for 0dBV/0dBW)	180mV (pre) / 127mV (power)
A-wtd S/N ratio (re. 0dBV/0dBW)	96.5dB (pre) / 98.5dB (power)
Distortion (20Hz-20kHz, 0dBV/10W)	0.0012-0.008% / 0.0016-0.045%
Power consumption (idle/rated o/p)	11W / 145W (4W, preamp)
Dimensions (WHD, Pre/Power)	250x71x230mm / 250x71x218mm