Modwright KWA 150
12/09 The Absolute Sound's Dick Olsher says:
"To my ears, the KWA 150 represents a smashing success, combining the musicality of tubes with the punch, power delivery and bass reach of transistors. Factor in the performance and looks of this amp relative to its asking price and the result is a fantastic value."
04/09 SixMoons.com Review - Terrific review, with great photos too!
Quality - "During the review period, two manufacturers or their representatives laid eyes on the KWA-150 while delivering their goods. And they invariably commented on the extravagant enclosure and its intricately carved out top. Unfamiliar with the brand, they also over-guessed the price by a factor of at least two. When I explained that this included being built in America and dealer distribution, the ensuing silence said all."
Sound - "Dynamics both micro and macro and ultra low-level fitness arguably score highest in what is a brilliant score card to begin with. I personally find macrodynamics to be less important since they apply mostly to symphonic music and anyone intent on recreating 'the real thing' on that score is hopelessly deluded. It's the microdynamics in the cramped 10dB of dynamic range that most music is recorded in today where the real differences occur between posthumous and alive, boring and compelling. Without being zippy, threadbare, nervous or hyped in the least, the ModWright KWA-150 despite its muscle beach allure is ideal for quiet yet fully satisfying sessions. Forget testosterone, that's what most music lovers do most of the time. They listen at from civilized to very subdued levels cognizant of neighbors and cohabitants, all the while longing for fulfillment from spirited sessions. That's where the KWA-150 delivers big time".- SixMoons
A revolutionary breakthrough in solid-state amp design!
The KWA 150 provides the strengths of both Tube and Solid State products: 3-D sound-staging, holographic imaging and beautiful midrange of tubes, combined with sparkling highs, low distortion, bass resolution and control of solid state.
The heart of the KWA 150 amplifier is a single voltage gain stage called the ‘Solid State Music Stage’. The circuit was developed by Alan Kimmel, creator of the exceptional vacuum tube ‘Mu’ stage. Its also a zero global feedback design with transformer-coupled true balanced floating inputs and direct-coupling from there into fully differential, pure solid-state circuitry. ModWright Instruments capacitors are used as power supply bypasses in key locations and total power supply capacitance reserves are 216,000uF.
Output short circuit protection as well as overload circuit protection operate completely outsid the signal path. Transformer coupling blocks out-of-band noise as well as errant DC from preamp or source. Modwright uses the highest-grade Thermal Trak bipolar output devices with auto thermal bias with six pairs per channel, i.e. six transistors per phase. The amp has a hi/lo bias feature for standby or cool operation (low bias); and best sonics and greater heat dissipation (high bias). But even in high bias, it still won't run as hot as pure class A. The amp is bridgeable to mono with a third set of binding posts and a stereo/mono switch. Tests have proven that it delivers 650 watts into a 4-ohm load then.
Features include: high-low bias switch, stereo/bridge-mono switch and true balanced floating inputs, accepting balanced and unbalanced inputs. The design incorporates a regulated power supply for the input stage, Cardas’ best connectors, oversized heat-sinks and silent comprehensive protection circuitry operating completely outside of the signal path. The first few watts operate in pure Class A.
Designed and built in the U.S.A.
AudioCircle thread on the KWA 150
StereoTimes RMAF 2008 commentary on the KWA 150
Frequency response: 16Hz to 220kHz
Weight: 80 pounds in the box
Dimensions: 18" x 18" x 8.75" WxDxH.
There are three 0.25"x20 threaded receptacles for spikes or other footers and the top cover matches the 36.5 preamp and external power supply.
