AVM Ovation CS 8.3 Black Ed. All-In-One Solution Lab Report

Lab Report

As we saw in the Ovation CS 8.2 [HFN May '17], which employed an earlier generation of Pascal's S-PRO2 Class D amp module, AVM's 500W/4ohm rating amounts to 2x245W/8ohm and 2x480W/4ohm in practice, with 240W, 510W and 830W achievable under dynamic conditions into 8, 4 and 2ohm loads [see Graph 1, below]. The modules are current-protected and so output into low (1ohm) loads is 'limited' to 380W (20.4A at <1% THD). The A-wtd S/N is a little below average at 78.4dB (re. 0dBW) but the response, which rolls gently away from –1dB/12kHz to –2.6dB/20kHz, takes the edge off any glare. The pattern of distortion, low at 0.007-0.009% through bass and midrange, increases more rapidly at HF to 0.03%/10kHz and 0.06%/20kHz (all re. 0dBW). Versus level, THD increases gently from 0.007%/1W to 0.02%/10W, 0.05%/100W and 0.1%/200W.

While these qualities are primarily linked to the Class D amp, the CS 8.3's preamp also picks up some slight 'colour' from the triode tube stage [see Graph 2] so that THD falls from 0.014-0.0013% over the top 30dB of the ES9018 DAC's dynamic range (the ES9038 claimed in AVM's literature is incorrect). However, with gain set to '+4' for a 2.03V preamp output, the 106.1dB A-wtd S/N ratio remains very respectable. The 'Steep' and 'Smooth' digital filters are both linear phase types, the former trading more extensive ringing for a full 83dB stopband rejection and flatter –1.3dB/20kHz, –5.5dB/45kHz and –13.6dB/90kHz response with 48kHz, 96kHz and 192kHz media. The 'Smooth' filter offers just 6dB of stopband rejection and a 'sweeter' –4.3dB/20kHz response, but ringing/time domain distortions are much reduced. It is recommended for 96kHz+ sample rates. PM

123avm.lab1

Dynamic power output versus distortion into 8ohm (black trace), 4ohm (red), 2ohm (blue) and 1ohm (green) speaker loads. Max. current is 20.4A

123avm.lab2

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

Power output (<1% THD, 8/4ohm) 245W / 480W
Dynamic power (<1% THD, 8/4/2/1ohm) 240W / 510W / 830W / 380W
Output imp. (20Hz–20kHz, Pre/Amp) 45ohm / 0.02-0.175ohm
Freq. resp. (20Hz–20kHz/100kHz) –0.07 to –2.6dB/–26.5dB
Digital jitter (CD / S/PDIF) 255psec / 250psec
A-wtd S/N ratio (DAC/Amp) 106.1dB (0dBFs) / 78.4dB (0dBW)
Distortion (DAC, 0dBFs/Amp, 10W) 0.013-0.017% / 0.017-0.085%
Power consumption (Idle/Rated o/p) 34W / 1.09kW (4W standby)
Dimensions (WHD) / Weight 430x130x380mm / 12kg
Price £15,950

COMPANY INFO
AVM Audio Video Manufaktur GmbH
Germany
Supplied by: The Professional Monitor Company Ltd
01767 686300
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