M-300B Tube vs BorderPatrol S20EXD Parallel SE w/EXD
The S20EXD Parallel SE w/EXD's power @ 8ω is 18W against the M-300B Tube's 8W, its power @ 4ω 18W against 4W, and its class A against Tube. Both share output impedance (4Ω).
AI-generated product photo — not official manufacturer imagery.
AmplifiersTube AmplifiersPower Amplifiers
Estimated price (community-sourced)
$6,750 - $30,000
Around — community and catalog average, updates slowly
About the M-300B Tube
The Austin Acoustic M-300B is a high-efficiency, single-ended-triode (SET) tube monoblock power amplifier built around a 300B output tube. Austin Acoustic’s product listing identifies a 436A driver tube and tube rectification, with approximately 5 watts of output and an unusually wide stated response of 20 Hz to 20 kHz. A contemporaneous listing for an M-300B version specifies Psvane WE300B and Western Electric 437A tubes, Tamura output transformers, a Tango interstage transformer and power-supply choke, silver signal wiring, selectable 4-, 8- and 16-ohm outputs, and approximately 4–8 watts. Some details therefore appear to vary by production version or source. The amplifier is intended for use with high-sensitivity loudspeakers, particularly horn systems. The manufacturer’s website still presents the model page, but the available evidence does not clearly establish whether new units are currently being manufactured or sold; confirm directly with Austin Acoustic.
Specifications
Power Specifications
Amplification power output and characteristics
- Power @ 8Ω
- 8W @ 8Ω
- Power @ 4Ω
- 4W @ 4Ω
- Amplifier Class
- tube
- Minimum Impedance
- 4Ω
Analog Output
Analog signal output specifications
- Output Impedance
- 4Ω
Connectivity
Input and output connections
- Analog Outputs
- speaker terminals with 4-, 8- and 16-ohm selections
Physical Dimensions
Size, weight, and appearance
- Dimensions
- 216 × 279.4 × 215.9 mm (W × H × D)
- Weight
- 20.41 kg (45 lbs)
Key Specifications
Power: 8W
Specifications are community-contributed and may not be accurate or complete. Verify all details with the manufacturer before making purchasing decisions. Terms & Conditions