Page 2 - Instructions for Use
KAV–2250Stereo Power Amplifier KAV–3250Three-channel Power Amplifier Instructions for Use v 01.2 Krell Industries, Inc. 45 Connair Road Orange, CT 06477-3650 USA TEL 203-799-9954 FAX 203-891-2028 E-MAIL [email protected] WEBSITE http://www.krellonline.com This product is manufactured in the Unit...
Page 3 - Contents; Page
Krell KAV–2250 and KAV–3250 iii Contents Page INTRODUCTION 1 DEFINITION OF TERMS 2 UNPACKING 4 PLACEMENT 5 AC Power Guidelines 5 FRONT PANEL DESCRIPTION 7 BACK PANEL DESCRIPTION 9 CONNECTING THE AMPLIFIER TO YOUR SYSTEM 11 Input and Output Connections 11 AMPLIFIER OPERATION 13 On/Off and Operation 1...
Page 4 - Illustrations
iv Krell KAV–2250 and KAV–3250 Illustrations Page FIGURE 1 The KAV–2250 Front Panel 6 FIGURE 2 The KAV–3250 Front Panel 6 FIGURE 3 The KAV–2250 Back Panel 8 FIGURE 4 The KAV–3250 Back Panel 8 FIGURE 5 Amplifier Factory Default Settings 16 FIGURE 6 Reconfiguring the KAV–2250 for MAT Operation 17 FIGU...
Page 5 - Introduction
Krell KAV–2250 and KAV–3250 1 Introduction Thank you for your purchase of the Krell KAV–2250 Stereo Power Amplifier or the KAV–3250 Three-channel Power Amplifier. The KAV–2250 and KAV–3250 amplifiers provide substantial two- and three-channel output power that delivers realistic music reproduction a...
Page 6 - Definition of Terms; CONFIGURATIONS; Bridging; INPUT AND OUTPUT CONNECTIONS; Balanced; Use care when using single-ended connections as the
2 Krell KAV–2250 and KAV–3250 Definition of Terms Following are the definitions of key terms used in your owner’s reference manual. CONFIGURATIONS Bridging A method of linking two amplifier channels by distributing the speaker load between the positive binding posts. Bridging the channels quadruples...
Page 7 - Definition of Terms,; OPERATION; Off; TECHNOLOGY; Krell Current Mode
Krell KAV–2250 and KAV–3250 3 Definition of Terms, continued OPERATION Off When the back panel power switch is in the down (off) position and the red stand-by LED turns off, the component is off. Stand-by Mode When the AC power cord is plugged into the wall and the back panel power switch is in the ...
Page 8 - Unpacking; or
4 Krell KAV–2250 and KAV–3250 Unpacking 1. Open the shipping box and remove the top layer of foam. You see these items: 1 amplifier unit (packed in foam end-caps) 1 IEC connector (AC power) cord 1 12 VDC output (12 V trigger) cable 1 T-15 Torx wrench KAV–2250 fuses: 2 AGC-12 (12-amp) or KAV–3250 fus...
Page 9 - Placement; AC POWER GUIDELINES
Krell KAV–2250 and KAV–3250 5 Placement Before you integrate your new amplifier into your system, please review the following guidelines to choose the location for the component. This will facilitate a clean, trouble-free installation. The amplifier requires at least two inches (5 cm) of clearance o...
Page 11 - Front Panel Description
Krell KAV–2250 and KAV–3250 7 Front Panel Description See Figures 1 and 2 on page 6 The front panel on the KAV–2250 and the KAV–3250 provides power on and indicates operating status. 1 Power Button Use this button to switch the power between the stand-by and the operational modes and also to switch ...
Page 13 - Back Panel Description; Balanced Inputs
Krell KAV–2250 and KAV–3250 9 Back Panel Description See Figures 3 and 4 on page 8 The back panel on the KAV–2250 and the KAV–3250 provides connections for all inputs and outputs, remote connection input and output links, and the AC power supply. See Reconfiguration Options for the KAV–2250 and the ...
Page 14 - Back Panel Description,; Fuses; Notes; Power
10 Krell KAV–2250 and KAV–3250 Back Panel Description, continued Fuses 10 AGC-12 Fuses The AGC-12 Amp loudspeaker fuses protect the amplifier against short circuits at the amplifier outputs. Back Panel Remote Connections 11 12 VDC Remote Power Out The amplifier is equipped with an output that sends ...
Page 15 - Connecting the Amplifier to Your System; The amplifier is equipped with balanced and single-ended inputs.
Krell KAV–2250 and KAV–3250 11 Connecting the Amplifier to Your System INPUT AND OUTPUT CONNECTIONS The amplifier is equipped with balanced and single-ended inputs. Krell recommends using balanced interconnect cables. Balanced interconnect cables not only can minimize sonic loss but are also immune ...
Page 16 - Connecting the Amplifier,
12 Krell KAV–2250 and KAV–3250 Connecting the Amplifier, continued 4. Connect the loudspeaker cables to the amplifier channel output binding posts located on the back panel, (8) on the KAV–2250 or (9) on the KAV–3250. The binding post terminals accept spade lugs, bare wire, or pins. Use the red term...
Page 17 - Amplifier Operation; ON/OFF AND OPERATION; illuminates and you hear a click.; USING A DEDICATED WALL SWITCH
Krell KAV–2250 and KAV–3250 13 Amplifier Operation ON/OFF AND OPERATION When powering up your system, turn amplifiers on last. When powering down your system, turn amplifiers off first. The procedures for amplifier operation follow. 1. Plug the AC power cord into the AC power wall receptacle. 2. Pus...
Page 18 - Troubleshooting System Noise; the other interconnect cables.
14 Krell KAV–2250 and KAV–3250 Troubleshooting System Noise When you mix and match high-performance audio components, each with its own ground potential, a low frequency hum may occur in one or all loudspeakers. If this happens when you place the amplifier into your system, follow these simple troub...
Page 19 - TO SAFELY ACCESS THE INPUT SWITCH BANKS; Unplug the AC power cord from AC power.
Krell KAV–2250 and KAV–3250 15 Reconfiguration Options for the KAV–2250 and KAV–3250 There are a number of options for reconfiguring the amplifier output: Multi Amp Throughput (MAT) is an internal connection option for the amplifier that lets you send the same music signal to all amplifier channels ...
Page 20 - Figure 5 Amplifier Factory Default Settings
Figure 5 Amplifier Factory Default Settings 1 2 O N 1 2 O N 1 S3 S1 Bridge Channel 1 Input Channel 2 Input MT1 J5 J6 S2 Input Circuit Board 3 1 2 O N 3 1 2 O N 3 1 2 O N 1 S4 S1 Bridge Channel 1 Input Channel 2 Input Channel 3 Input MT1 J7 J8 J9 S3 S2 Input Circuit Board KAV–2250 KAV–3250 1 2 O N Sw...
Page 21 - Figure 6 Reconfiguring the KAV–2250 for MAT Operation; Figure 7 Reconfiguring the KAV–3250 for MAT Operation
Figure 6 Reconfiguring the KAV–2250 for MAT Operation 1 2 O N 1 2 O N 1 S3 S1 Bridge Channel 1 Input Channel 2 Input MT1 J5 J6 S2 Input Circuit Board Figure 7 Reconfiguring the KAV–3250 for MAT Operation 3 1 2 O N 3 1 2 O N 3 1 2 O N 1 S4 S1 Bridge Channel 1 Input Channel 2 Input Channel 3 Input MT1...
Page 22 - Reconfiguration Options,; AMPLIFIER FACTORY DEFAULT SETTINGS; RECONFIGURING THE AMPLIFIER FOR MAT OPERATION; To send the signal from a source device connected to input 1:
18 Krell KAV–2250 and KAV–3250 Reconfiguration Options, continued Accessing the Input Switch Banks, continued 6. Reconfigure your amplifier, using the scenarios described below. 7. After the component is configured, replace the cover and, using the T-15 Torx wrench, secure all 12 cover screws. IMPOR...
Page 23 - To send the signal from a source device connected to input 2:
Krell KAV–2250 and KAV–3250 19 Reconfiguration Options, continued Reconfiguring the KAV–2250 for MAT: Send One Input Signal to Both Output Channels via Input 2 Not illustrated To send the signal from a source device connected to input 2: 1. Push switch 2 up (on) for both input switch banks. 2. Push ...
Page 24 - Figure 8 Reconfiguring the KAV–2250 for Bridged Operation; Figure 9 Reconfiguring the KAV–3250 for Bridged Operation
Figure 8 Reconfiguring the KAV–2250 for Bridged Operation 1 2 O N 1 2 O N 1 S3 S1 Bridge Channel 1 Input Channel 2 Input MT1 J5 J6 S2 Input Circuit Board Figure 9 Reconfiguring the KAV–3250 for Bridged Operation Input Circuit Board 3 1 2 O N 3 1 2 O N 3 1 2 O N 1 S4 S1 Bridge Channel 1 Input Channel...
Page 25 - Connecting the Amplifier Reconfigured for MAT; RECONFIGURING THE AMPLIFIER FOR BRIDGED OPERATION; Connecting the Amplifier Reconfigured for Bridged Operation
Krell KAV–2250 and KAV–3250 21 Reconfiguration Options, continued Connecting the Amplifier Reconfigured for MAT 1. Connect the cable from your source device to the balanced or single-ended input you have selected to receive the signal. (For example, if you use the switch settings shown in Figure 6 y...
Page 26 - EXAMPLE OF A CONNECTION SCENARIO: MULTI-POWER MODE
+ – + – + – + + + Kitchen (R) Patio (R) Gym (R) + + + + – + – + – Kitchen (L) Patio (L) Gym (L) – – – – – – Left Amplifier Right Amplifier Left Speakers Right Speakers 22 Krell KAV–2250 and KAV–3250 EXAMPLE OF A CONNECTION SCENARIO: MULTI-POWER MODE Multi-power mode is a possible connection scenario...
Page 27 - Questions and Answers; Q. Should I turn the amplifier off when not playing music?
Krell KAV–2250 and KAV–3250 23 Questions and Answers Q. Should I turn the amplifier off when not playing music? A. No. Leave the amplifier in stand-by when not playing music. The stand-by mode avoids cold starts as well as minimizes heat output and power consumption. Krell recommends turning the amp...
Page 28 - Warranty
24 Krell KAV–2250 and KAV–3250 Warranty This Krell product has a limited warranty of five years forparts and labor on circuitry. Should this product fail to per-form at any time during the warranty, Krell will repair it at nocost to the owner, except as set forth in this warranty. The warranty does ...
Page 30 - Specifications
26 Krell KAV–2250 and KAV–3250 Specifications KAV–2250 FREQUENCY 20 Hz to 20 kHz +0 dB, -0.09 dB RESPONSE 0.25 Hz to 170 kHz +0 dB, -3 dB SIGNAL TO NOISE RATIO “A” WEIGHTED >112 dB TOTAL HARMONIC 1 kHz < 0.03% DISTORTION (THD) 20 kHz < 0.20% GAIN 25.7 dB INPUT IMPEDANCE 100 kOhms INPUT SENS...
