Often overlooked, the preamplifier is a critical component in the signal chain. A small signal must be carefully amplified without damaging the ephemeral staging and dimensional components of the music.

The Evolution 202, using a combination of advanced technologies and inspired design, elevates this task to an art form. Music emanates from an expanse that outlines the recording venue, transporting you to the moment of creation. With the Evolution 202 Preamplifier, musicians appear, silhouetted by the air about them, filling the room with a mesmerizing depiction of the recording.

Available in silver or black.

1.5 MHz open loop bandwidth in a zero feedback, balanced, Krell Current Mode design terminating in Krell CAST. All signal gain is realized in a surface mount topology using proprietary multiple-output current mirrors with nearly 500 times the open loop linearity of other designs. Zero negative feedback is used anywhere in the preamp, nor is it necessary. Open-loop distortion is typically less than 0.005% (50 parts per million).

A complete Evolution (source, preamplifier, amplifier) system, connected in CAST, reduces the number of voltage gain stages to the minimum, one. The resulting noise floor is approaching the theoretical limit of technology. The volume control is realized with a 16-bit balanced resistor ladder --bandwidth and transient response of the preamp circuitry are virtually unaffected by the volume setting.

Housed in a separate chassis, the power supply makes use of extensive electrical and magnetic shielding to keep radiated interference out of critical preamplifier circuits. A 170 VA toroidal transformer drives four 8-amp bridge rectifiers and 39,600 microfarads of filter capacitance.

A new Krell designed digital control circuit monitors and optimizes the preamplifier's operating parameters.

2 pr. CAST via 4-pin bayonet connectors
2 pr. balanced via XLR connectors
3 pr. single-ended via RCA connectors
Tape input
1 pr. single-ended via RCA connector
Main outputs
2 pr. CAST via 4-pin bayonet connectors
1 pr. balanced via XLR connector
1 pr. single-ended via RCA connector
Tape outputs
1 pr. single-ended via RCA connector, buffered
Control inputs
1 RS-232 input via a 9-pin D-subminiature connector
1 remote IR detector input via a 3-conductor 3.5 mm connector
1 12 VDC trigger input via 3.5 mm connector
1 preamplifier link via an RJ-45 connector
Control outputs
2 individually programmable 12 VDC
trigger outputs via 3.5 mm connectors
1 preamplifier link via an RJ-45 connector
Power output
1 phono power output (+/-20 VDC) for KPE
via a 9-pin D-subminiature connector
Input impedance
CAST: 45 Ohms
Balanced: 95 k Ohms
Single-ended: 47.5 k Ohms
Output impedance
CAST: >1 M Ohms
Balanced: 50 Ohms
Single-ended: 25 Ohms
12 dB (CAST or balanced output)
6 dB (single-ended output)

Volume control
Balanced, current-mode,
16-bit, discrete R-2R ladder
Input overload
Balanced: 14 V RMS
Single-ended: 7 V RMS
Output overload
Balanced: 16 V RMS
Single-ended: 8 V RMS
Frequency response
20 Hz to 20 kHz +/- 0.02 dB
0.1 Hz to 1.5 MHz +0, -3 dB
Total harmonic distortion plus noise
Balanced Output:
<0.004%, 20 Hz to 20 kHz, 4 V RMS or 4 mA RMS
Signal-to-noise ratio
4 V RMS balanced or 4 mA RMS CAST output
Wideband, unweighted: >100 dB
"A" weighted: >109 dB
Power consumption
Standby: 45 W
Power on: 70 W
Power on, with KPE: 80 W
Preamplifier only:
17.3 in.W x 3.8 in. H x 18.3 in. D
43.8 cm W x 9.7 cm H x 46.4 cm D
Power supply only:
17.3 in. W x 3.8 in. H x 17.7 in. D
43.8 cm W x 9.7 cm H x 44.8 cm D
Preamplifier and power supply:
17.3 in. W x 7.6 in. H x 18.3 in. D
43.8 cm W x 19.2 cm H x 46.4 cm D
Shipped: 61 lbs., 27.6 kg
Preamplifier only: 18 lbs., 8.1 kg
Power supply only: 28 lbs., 12.7 kg



"I can't imagine any music lover not responding to their performance, which is darn nigh flawless"

Home Theater Review

" The Krell Evolution 202's design featuring a two-chassis system is smart and results in a preamp that is nothing short of magical."

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