McIntosh MC7300 (1991–1995)

A high-power solid-state stereo amplifier with advanced protection systems and precision metering, built for stability across demanding speaker loads.

Overview

The McIntosh MC7300 is a stereo power amplifier built from 1991 to 1995. It delivers 300 watts per channel continuously into 2, 4, or 8 ohms. It can also run in mono bridge or parallel modes, and either way it makes 600 watts. McIntosh marketed it as a "DIGITAL DYNAMIC STEREO POWER AMPLIFIER." The design aims at low distortion, high damping factor, and comprehensive protection. It shares circuit design elements with the MC2600 and puts out half the power of that flagship.

Specifications

Output Stereo	300W + 300W (Sine Wave Continuous Output, Load Impedance 2/4/8 Ω)
Output Mono bridge	600W (sine wave continuous output, load impedance 4/8/16 Ω)
Output Mono / Parallel	600W (Sine Wave Continuous Output, Load Impedance 1/2/4 Ω)
Output impedance Stereo	2 Ω, 4 Ω, 8 Ω
Output impedance Mono bridge	4/8/16 Ω
Output impedance Mono / Parallel	1/2/4 Ω
Output frequency band	20 Hz to 20 kHz
Frequency Band (at 1W output)	20 Hz to 20 kHz, +0 -0.25 dB
Frequency Band (at 1W output)	10 Hz to 100 kHz, +0 -3.0 dB
Total harmonic distortion factor Stereo	0.005% or Less (20 Hz to 20 kHz, 250 mW to 300W, when both channels are driven)
Total harmonic distortion factor Monaural	0.005% or Less (20 Hz to 20 kHz, 250 mW to 600W, when both channels are driven)
Cross modulation distortion factor Stereo	0.005% or less (with one channel, peak 300W or less)
Cross modulation distortion factor Monaural	0.005% or less (peak 600W or less per channel)
Signal-to-noise ratio	105 dB or less (at rated output, A-weighted)
Dynamic headroom	1.9dB (IHF)
Damping factor	40 or more
Input impedance	20k Ω (unbalanced)
Input impedance	40k Ω (balanced)
Input sensitivity	Switching to 2.5 v, 1.4 v
Power Guard	Overdrive at 1 kHz up to 14 dB THD within 2%
Power	100 VAC, 50Hz/60Hz, 0.6A ~ 13A
External dimensions	Width 443x Height 196x Depth 420 mm (including terminal)
Weight	35kg

Design

The signal circuit comes from the MC2600 and takes balanced and unbalanced inputs. After the pre-drive stage the amplification is symmetric, and an auto-tracking bias system prevents crossover distortion. The output transformer is newly designed and can deliver peak output current over 85A, so the amp stays stable regardless of load. The power meter is large and fast. It calculates actual output voltage and current, has peak hold, and responds approximately 10 times faster than a standard VU meter. The gold-plated output terminals take cables up to 6 mm in diameter. There are seven integrated protection systems. Power Guard compares input and output waveforms and reduces gain if distortion goes past a set threshold. An automatic thermal cutout kicks in on overheating.