Fig.9 McIntosh MC2000, distortion (%) vs continuous output power into (from bottom to top at 2kHz) 4 ohms, 8 ohms, and 2 ohms (matched impedance taps).
Table 1 McIntosh MC2000 Clipping(1% THD+noise at 1kHz)
| Both Channels Driven | One Channel Driven | ||
| W (dBW) | W (dBW) | ||
| Load ohms | (L) | (R) | (L) |
| 8 | 162 (22.1) | 164.3 (22.16) | 172.2 (22.36) |
| (line) | 114V | 115V | 116V |
| 4 | 165.5 (19.19) | 164.9 (19.17) | 176.8 (19.47) |
| (line) | 114V | 114V | 115V |
| 2 | 164.4 (16.16) | ||
| (line) | 116V | ||
Using the Miller Audio Research Amplifier Profiler to examine the McIntosh's power capabilities using a low-duty-cycle 1kHz toneburst with one channel driven, John Atkinson found it be a powerhouse. Matching the tap to the load gave around 200W at 1% THD+N. But almost the same power was available into lower impedances. Fig.10, for example, shows that while the 4 ohm tap will deliver 139W into 8 ohms and 205W into 4 ohms, it will still output 199W into 2 ohms and even 107W into 1 ohm, the latter equivalent to an RMS output current of 10.35A! If you're looking for a tube amplifier to drive your old Apogee ribbons, the McIntosh from its 4 ohm or 2 ohm taps will be the perfect choice.
Fig.10 McIntosh MC2000, distortion (%) vs 1kHz burst output power into 8 ohms (black trace), 4 ohms (red), 2 ohms (blue), and 1 ohm (green).
While not remarkable, the MC2000's test-bench results are more than respectable for a modern tube amplifier, and certainly better than most of the breed, particularly regarding output current capability.—Thomas J. Norton
