Krell Evolution 403e black - mint w/warranty - $3k under blue book

Clarification: This listing is for an Evolution 403e (with transferable warranty remaining and original packaging and unused accessories), NOT the older 403. This is the current model until January 2014. To upgrade an EV403 (2004 - 2009) to an EV403e (2009 - 2014) costs $5,000 plus shipping both ways. The 403e has all new output stages and sounds better in every respect. It also consumes 368 watts less power in "e" standby mode.

I’m the original owner of this amazing amplifier built in March of 2011. It is in perfect, like-new condition. Not a scratch or flaw anywhere. Transferable warranty until March 2016. Only reason for sale, I moved up to the final amplifier frontier...a pair of Evolution 900e amplifiers! This amplifier has tremendous control, detail, soundstaging, dynamics, and bandwidth as all Krell power amps do. This amplifier is equally suited to high end, 2-ch audio with it’s 6000 VA power transformer, or home theater as well. Pairing this amplifier with any of the Krell CAST pre-amps or the Krell EV707 takes audio to the next level! Shipping through UPS Supply Chain Solutions is ~$400 within continental US. I will bring the amplifier to the shipping facility to make it as economical as possible for the buyer. Standard payment PayPal add 4%. PayPal "friends and family" has no payment fees at all. Thanks for looking.

The Evolution 403e is the most powerful three channel amplifier available today. Housed in the same chassis as the Evolution 900e, the Evolution 403e is the perfect choice for stereo amplification or Left, Center, and Right channels in a high performance home theater. For reference caliber performance, coupling the Evolution 403e to Evolution 900e, Evolution 600e, or an Evolution 402e elevates an already potent system to new heights. At a staggering 1,600 watts into 2 Ohm loads, the Evolution 403e is a virtually limitless source of power for any speaker. Power is critical for the explosive dynamics that is essential to the high performance audio or home theater experience. This power capability is coupled to a new green operating mode that reduces standby electrical draw to a mere 2 Watts. However, power alone is not the goal as film soundtracks are the emotional vehicles in movies. It is music, not on-screen action, that communicates loss, fear, victory, and determination in movies - think of Rocky, Darth Vader, and Jaws without their theme music. Conveying emotion through music is the true strength of the Evolution 403e and an essential element for stereo and home theater listening.

The Evolution 403e is equipped with two 3,000 VA transformers and 188,000μF. This power source is the backbone for the output of the Evolution 403e. With this foundation, the Evolution 403e delivers 400 watts into 8 Ohms and 800 watts into 4 Ohms and 1600 watts into 2 Ohms with all three channels driven simultaneously. The FTC mandates that power ratings are quoted using a 1,000 Hz sine wave into a fixed 8 Ohm resistor with final power specification stated at 1% distortion. Krell engineering considers this specification too lenient and not indicative of what an amplifier is required to provide. Krell designs to a much stricter standard. Our power tests use a 20-20,000Hz signal into 8, 4, and 2 Ohm loads. Our power tests use a 20-20,000Hz signal into 8, 4, and 2 Ohm loads with our final specifications stated for .1% distortion.

Internal high-current line conditioning circuitry effectively blocks RF noise entering via the AC line and compensates for any asymmetry or DC offset in the power waveforms. The amplifiers’ low level and gain stages are powered via multi regulated rails that provide total immunity from supply fluctuations and assure noise-free circuit operation. Primary rail voltages are quasi-regulated, enabling an "on-demand" supply of power that is highly responsive to dynamic load.

Krell’s new Active Cascode Topology™ is a significant departure from traditional amplifier circuits where the positive and negative rail voltages are each applied entirely across a single row of transistors. High voltage swing and gain requirements dictate that the transistors be "pushed" into non-linear operating regions and, in some cases, dangerously close to breakdown. Krell topology divides the full voltage swing across multiple rows of transistors, and all devices are active-biased (i.e., they all carry the audio signal). Because individual transistors in the cascode array "see" only a proportional fraction of the rail voltage, they operate in a region that provides optimum linearity, gain, and safety. And because the devices are not being pushed to their limits, the amplifier runs cooler and more reliably. The improved linearity and stability greatly reduces the need for negative feedback, which is known to cause sonic degradation. Krell Evolution power Amplifiers use only 14 dB of feedback throughout the topology-a small fraction of the amount implemented in typical designs.

Krell Active Cascode Topology offers several performance advantages. It breaks through bandwidth limitations of conventional designs and delivers very high current. The usable bandwidth of an Evolution 403e is 300 kHz; triple the bandwidth of a typical high performance amplifier. The result is near perfect performance in the audible range with no phase anomalies typical of lower bandwidth designs. Because the "work" is spread across multiple devices, the amplifier is more load tolerant. Open-loop output impedance is extremely low-about one hundred times lower than with most power amplifiers-ensuring exceptional speaker control. All of these performance gains are achieved while maintaining a high rail voltage, which provides a beneficial "flywheel" effect-a de facto regulation that enables the amplifier to better deal with sudden changes in power requirement, such as those caused by large signal transients.

Evolution amplifiers feature Krell CAST technology. CAST is a unique circuit and connection breakthrough that eliminates distortions inherent in voltage based amplification. A complete Evolution (source, preamplifier, and amplifier) system, connected with CAST interconnects reduces the number of voltage gain stages to the minimum, one. The resulting noise floor is approaching the theoretical limit of technology. Emanating from a completely black background, music explodes from absolute silence moving the listener closer to the goal of recreating the live musical event in the listening room.

Specifications

Evolution 403e

Frequency Response

20 Hz to 20 kHz +0, -0.17 dB

<0.5 Hz to 125 kHz +0, -3 dB

Signal to Noise Ratio

>106 dB, unweighted, referred to full power output

>116 dB, "A"-weighted

Gain

25.4 dB

Total Harmonic Distortion

<0.02% at 1 kHz, at 400 W, 8 Ohms

<0.15% at 20 kHz, at 400 W, 8 Ohms

Input Impedance

Single Ended: 100 kOhms

Balanced: 200 kOhms

CAST: 70 Ohms

Input Sensitivity

Single Ended or Balanced: 3.04 V rms

CAST: 3.04 mA rms

Output Power

400 W RMS at 8 Ohms

800 W RMS at 4 Ohms

1600 W RMS at 2 Ohms

Output Voltage

160 V peak-to-peak

57 V RMS

Output Current

37 A peak

Slew Rate

100 V/µs

Output Impedance

<0.055 Ohms at 20 Hz

<0.064 Ohms, 20 Hz to 20 kHz

Damping Factor (referred to 8 ohms)

>145 at 20 Hz

>125, 20 Hz to 20 kHz

Transformers

Two 3000 VA (6000VA total) for audio circuitry

One 10 VA for digital control circuitry

Power Supply Capacitance

108,000 µF

Power Consumption

Standby: 2 W

(High-current standby: 370W)

Idle: 570 W

Maximum: 5000 W

Heat Output

Stand-by: 7 BTU/hr.

(High-current standby: 1270 BTU/hr.)

Idle: 1950 BTU/hr.

Maximum: 7700 BTU/hr.

Inputs

3 single-ended via RCA connector

3 balanced via XLR connector

3 CAST via 4-pin bayonet connector

Outputs

3 pairs Krell binding posts

Dimensions

17.3 in. W x 9.8 in. H x 26.1 in. D

438 mm W x 248 mm H x 662 mm D

Weight

Shipped: 195 lb., 88.4 kg

Unit Only: 175 lb., 79.2 kg