ModWright KWA 300 Reference Stereo Power Amplifier

Big, demanding speakers need real power. Music needs flow, texture, and life. Most listeners end up choosing one. The KWA 300 is ModWright's answer for the listener who wants both: 300 watts per channel, built around a circuit designed to sound like music first.

It's the newest chapter in a long story. ModWright's solid-state amplifiers grew from the KWA 150, which earned worldwide recognition for bringing some of the warmth and dimension of tubes to the control and drive of solid-state. Every KWA amplifier since has used the same foundation, the Solid State Music Stage, originally developed by Alan Kimmel and refined by Dan Wright for more than twenty years. The KWA 300 is that design at its fullest, with more power, lower noise, and greater precision than any KWA before it.

Reference power that still sounds like music.

The Design

The KWA 300 uses a single gain stage. Fewer stages mean a shorter signal path and timing that stays intact, which you hear as music that flows naturally and sounds whole.

It also runs with zero global feedback. Feedback is a way of correcting an amplifier's output after the fact; it lowers measured distortion, and many designers, Dan Wright among them, find it can also dull the life and immediacy of the sound. ModWright designs the circuit to be clean on its own, so the amplifier delivers what the music asks for, as it happens.

Both the RCA and XLR inputs feed a discrete differential input stage through transformers with a floated ground. Those transformers isolate the KWA 300 from noise and ground interference coming from the rest of your system, and both inputs get the same clean treatment. Run a balanced preamp or a single-ended one; at 47k ohms, the input works happily with virtually any preamplifier.

Power Supply

A 2KVA toroidal transformer anchors a high-capacity power supply. That's a lot of transformer for a stereo amplifier, and it's what lets the KWA 300 meet a sudden orchestral swell or a kick drum with full force and composure. The ratings show it: 300 watts into 8 ohms and 550 watts into 4. Power that nearly doubles as impedance halves is the sign of a supply with genuine current in reserve.

The output stage runs Class A/B with a high Class A bias. At the moderate levels where most listening happens, the KWA 300 plays in the smooth, sweet Class A region, and it stays efficient and comfortable to live with at this power level.

How It Sounds

ModWright set out to capture what makes live music compelling: power, detail, and emotion, with a balance of warmth and accuracy. Its signature is an organic sound, the natural flow and dimension more often associated with great tube amplifiers, and the KWA 300 carries it with more authority than any KWA before it.

Stereophile heard that character at SouthWest Audio Fest 2026, where the KWA 300, driven by ModWright's LS 300, produced a warm, sweetly lush sound with layered music beautifully separated in space. If you've loved tubes for their tonal realism and wished for more power and control, the KWA 300 belongs on your short list.

Connections and Features

• Two RCA inputs and two XLR inputs, all transformer-coupled.
• WBT binding posts, one pair per channel.
• 12V trigger input and output, so the KWA 300 powers on and off with your preamp and can pass the trigger on to another component.
• Internal LED switch to turn off the front-panel lighting for listening in the dark.

Where It Fits

The KWA 300 is ModWright's reference amplifier, built for full-range speakers, low-sensitivity designs, and big rooms. It's a natural partner for the LS 300 preamplifier, the pairing Stereophile heard, and it works beautifully with the LS 99 or any quality preamp, balanced or single-ended. For smaller rooms or more sensitive speakers, ModWright's compact KWA 99 monoblocks follow the same philosophy with 100 watts per channel.

Plan for its size. At 95 pounds and 18 inches wide, the KWA 300 wants a sturdy shelf or amp stand with room to breathe. Every KWA 300 is designed and hand-assembled in Amboy, Washington.

Press Recognition

• Stereophile, SouthWest Audio Fest 2026 show coverage. Driven by ModWright's LS 300 preamplifier into Alta Audio speakers, the KWA 300 earned a thumbs-up from Stereophile, which heard a warm, sweetly lush sound with layered synths beautifully separated in space. Stereophile's Ken Micallef also interviewed Dan Wright about the KWA 300 for the magazine's YouTube channel. Read the show report at Stereophile

Full reviews are on the way, and we'll add them here as they're published.

Wondering whether the KWA 300 suits your speakers, room, and preamp? Give us a call, and we'll work through sensitivity, impedance, and gain with you.

Specifications

• Type: Solid-state stereo power amplifier
• Topology: Single gain stage, zero global feedback, discrete differential input stage (Solid State Music Stage)
• Operation: Class A/B with high Class A bias
• Power output: 300W into 8 ohms, 550W into 4 ohms
• Gain: 30dB
• Frequency response: 10Hz to 200kHz (+0, -1dB)
• THD: Less than 0.02%
• Input impedance: 47k ohms
• Inputs: 2 x RCA, 2 x XLR, transformer-coupled to the input stage with floated ground
• Speaker outputs: 2 pairs WBT binding posts, one per channel (positive red, negative white); stereo operation
• Power supply: 2KVA toroidal transformer, high-capacity reservoir
• Triggers: 12V input and output
• Internal LED switch: Turns front-panel lighting on or off
• Dimensions: 18" W x 18.5" D x 9" H (height includes footers; depth includes 1" binding posts)
• Weight: 95 lbs (110 lbs shipped)
• Finishes: Silver aluminum, black anodized aluminum
• Designed and hand-assembled: Amboy, Washington, USA