Note updated February 11th: This product is backordered until April 15th. 

A fully-balanced Class-D amplifier that fits anywhere

A compact power amplifier that blends precision, power, and balance. The TOPPING Mini 300 delivers 140 watts per channel into 4Ω with astonishingly low distortion—less than 0.0005% THD+N at 8Ω, 5W output. Its fully-balanced Class-D architecture ensures an exceptionally clean signal path, while its quiet 124dB SNR keeps the background utterly black. Whether driving bookshelf speakers in your office or powering monitors on your desk, the Mini 300 brings clarity, composure, and control to every listening session.

Power that fits anywhere

The Mini 300 is built for people who want serious power without surrendering their workspace. At just 6.5" wide, it slips easily into desktop rigs or nearfield listening stations. Don’t let the small size fool you—this amp pushes 140W × 2 into 4Ω, plenty to drive demanding passive speakers with headroom to spare. Its all-aluminum chassis not only looks refined but also doubles as a heat sink, with bottom and side vents that quietly manage thermals while you enjoy long listening sessions.

Balanced architecture, balanced sound

Inside, the Mini 300 runs a fully-balanced Class-D circuit. That means each channel has its own complete amplification path, eliminating crosstalk and rejecting external noise before it ever touches your speakers. The result is an ultra-quiet floor—124dB SNR and less than 15μVrms of noise—so the only thing you’ll hear is the music itself. Smooth, transparent, and effortlessly controlled.

Precision that’s audible

Measurements don’t make music, but they help explain why the Mini 300 sounds so composed. At 5W into 8Ω, total harmonic distortion plus noise measures below 0.0004%. That’s vanishingly low, translating to clean transients, stable imaging, and lifelike dynamics even at low volumes.

Auto-on convenience

The 12V trigger input lets the Mini 300 power on and off in sync with your DAC or preamp—no reaching behind your stack or fumbling for switches. Once connected, it wakes up and shuts down with your system. 

Dual inputs

The rear panel accepts both balanced TRS and unbalanced RCA inputs, no adapters needed. Balanced inputs offer better rejection of interference for longer cable runs, while RCA keeps compatibility with everyday sources. Flip the front switch between BAL and SE to match your source, and you’re good to go.

Safe, silent, reliable

Power on and off are handled quietly, with protection circuitry guarding against overcurrent and overheating. 

Product highlights

• 140W × 2 @ 4Ω (THD+N <10%)
  
• 125W × 2 @ 4Ω (THD+N <1%)
  
• 85W × 2 @ 8Ω (THD+N <10%)
  
• 65W × 2 @ 8Ω (THD+N <1%)
  
• THD+N as low as 0.0004% @ 8Ω, 5W
  
• 124dB SNR / 124dB DNR
  
• Fully-balanced Class-D amplification
  
• 12V trigger auto power on/off
  
• TRS (balanced) and RCA (unbalanced) inputs
  
• All-aluminum chassis in three finishes
  
• Cooling vents on sides and bottom
  
• Overcurrent and thermal protection
  

Specs

• Input: SE / BAL
  
• THD+N @1kHz (A-wt): <0.0006% (SE) / <0.0005% (BAL) @4Ω 5W
  
• THD+N @No-wt 20kBW: <0.0010% @4Ω 5W
  
• SNR @MAX OUT 1kHz (A-wt): 121dB (SE) / 124dB (BAL)
  
• Dynamic range @1kHz (A-wt): 121dB (SE) / 124dB (BAL)
  
• Frequency response: 20Hz–40kHz (±0.3dB)
  
• Output level: 65Vpp @4Ω / 68Vpp @8Ω
  
• Noise (A-wt): <15μVrms
  
• Channel crosstalk @1kHz: -90dB (SE) / -106dB (BAL)
  
• Input sensitivity: 1.3Vrms (SE) / 2.6Vrms (BAL)
  
• Gain: 25.0dB (SE) / 19.2dB (BAL)
  
• Channel balance: 0.1dB
• Load impedance: 4–8Ω
  
• Output power:
  
  • 140W × 2 @4Ω (THD+N <10%)
    
  • 125W × 2 @4Ω (THD+N <1%)
    
  • 85W × 2 @8Ω (THD+N <10%)
    
  • 65W × 2 @8Ω (THD+N <1%)
    
• Dimensions: 6.5 × 5.1 × 1.6in (16.6 × 12.9 × 4.1cm)
  
• Power supply: DC 38V
  

What’s included

• Mini 300 amplifier
  
• Power adaptor
  
• Power cable
  
• Product information card