McIntosh MA9500 Integrated Amplifier Lab Report

Lab Report

Although the principal claim to fame for the MA9500 is its increased reservoir capacitance and higher dynamic output over the lookalike MA9000 [HFN Sep '18], in practice there's not a substantial difference. Continuous outputs are 2x420W/8ohm and 2x415W/4ohm for the MA9000 versus 2x430W/8ohm and 2x425W/4ohm for the MA9500. Under dynamic conditions the MA9000 achieved 575W/8ohm, 545W/4ohm and 560W/2ohm via the 8, 4 and 2ohm output taps, respectively, with 935W/1ohm (30.6A) also via the 2ohm tap. Under the same conditions the MA9500 offers 597W, 557W, 582W and 1020W (31.9A) into 8, 4, 2 and 1ohm loads [Graph 1, below]. As before, distortion is well 'buffered' against output level or loading at ~0.0015-0.002% over the first 100W and with frequency from 0.0007%/20Hz to 0.002%/20kHz. Noise is moderately low, yielding an A-wtd S/N ratio of 87.4dB (re. 0dBW) while its frequency response stretches from –0.25dB/20kHz to –3.2dB/100kHz (8ohm tap).

The latest digital board, now based on an ESS9028PRO DAC with its default 'fast' linear phase filter, offers a much reduced 0.0006-0.008% distortion [see Graph 2] from its balanced preamp outputs (4V, with volume at 70%; maximum 16.3V at 94% volume). The preamp response achieves +0.0dB/20kHz, +0.4dB/45kHz and +0.1dB/90kHz with 48kHz, 96kHz and 192kHz media, respectively. The A-wtd S/N ratio remains a respectable 111dB and jitter is low, but not vanishingly so, at <220psec (all sample rates). Encouragingly, the MA9000's premature truncation of low-level detail is 'fixed' in the MA9500 which enjoys a fine ±0.4dB resolution at –100dBFs and ±1.1dB at –110dBFs. So this is more than a 'buffed up' MA9000! PM


Dynamic power output versus distortion into 8ohm (black trace), 4ohm (red), 2ohm (blue) and 1ohm (green) speaker loads. Max. current is 31.9A


Distortion versus 24-bit digital signal level over a 120dB range at 1kHz (black) and 20kHz (blue)

Continuous power (<1% THD, 8/4ohm) 430W / 425W
Dynamic power (<1% THD, 8/4/2/1ohm) 597W / 557W / 582W / 1020W
Output imp. (20Hz-20kHz, Pre/Amp) 215ohm / 0.135-0.155ohm
Freq. response (20Hz-20kHz/100kHz) –0.3dB to –0.25dB/–3.2dB
Digital jitter (48kHz/96kHz) 220psec / 125psec
A-wtd S/N ratio (DAC/Amp, 0dBW) 111.0dB / 87.4dB
Distortion (DAC, 0dBFs/Amp, 10W) 0.0006-0.0075%/0.0007-0.002%
Power consumption (Idle/rated o/p) 71W / 1.2kW (1W standby)
Dimensions (WHD) / Weight 445x240x559mm / 45.8kg
Price £14,995

McIntosh Labs
Binghamton, NY, USA
Supplied by: Fine Sounds UK
01592 744710