Krell Industries KAV-250a/3 manuale d’uso

Leader in Audio Engineering KAV-250a Stereo Power Amplifier KAV-250a/3 Three-Channel Power Amplifier Instructions for Use, v 99.2 Owner’s Reference[...]

KAV-250a Stereo Power Amplifier and KAV-250a/3 Three-Channel Power Amplifier Instructions for Use, v 99.2 Cover: KAV-250a/3 Three-Channel Power Amplifier Krell Industries, Inc. 45 Connair Road Orange, CT 06477-3650 USA TEL 203-799-9954 FAX 203-799-9796 E-MAIL krell @ krellonline.com WEBSITE http://www.krellonline.com This product complies with the [...]

Contents INTRODUCTION ’ DEFINITION OF TERMS UNPACKING PLACEMENT AC Power Guidelines FRONT PANEL DESCRIPTION: KAV-250a BACK PANEL DESCRIPTION: KAV-250a FRONT PANEL DESCRIPTION: KAV-250a/3 BACK PANEL DESCRIPTION: KAV-250a/3 CONNECTING THE KAV-250a or KAV-250aJ3 AMPLIFIER TO YOUR SYSTEM Input and Output Connections OPTIONAL SYSTEM CONFIGURATIONS Mul[...]

Illustrations FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 The KAV-250a Front Panel The KAV-250a Back Panel The KAV-250a/3 Front Panel The KAV-250a/3 Back Panel Reconfiguring the KAV-250a for MAT or Bridged Operation FIGURE 6 Reconfiguring the KAV-250a/3 for MAT or Bridged Operation Page 4 6 9 11 16 19 iv KAV-250a and KAV-250a/3 Amplifiers[...]

Introduction Thank you for your purchase of the Krell KAV-250a Stereo Power Amplifier or KAV-250a/3 Three-Channel Power Amplifier.. The KAV-250a and KAV-250aJ3 amplifiers provide substantial two- and three-channel output power that delivers realistic music production at an exceptional value. These amplifiers can be customized with a variety of opti[...]

Unpacking Open the shipping box, which contains: 1 amplifier unit (packed in foam end-caps) 2 ribbon connection cables KAV-250a fuses: 2 AGC-8 (~ ’amp) 1 slow-blow (20 amp for 100/120 V or 12 amp for 220/240 V) or KAV-250a/3 fuses: 3 AGC-.8 ~ amp) 1 slow-blow (20 amp for 100/120 V or 12 amp for 220/240 V) 1 12 VDC output (12 V trigger) cable 1 IE[...]

Placement Before you integrate the KAV-250a or KAV-250a/3 into your system, review the following guidelines to choose the location for the component. This will facilitate a clean, trouble-free installation. The KAV-250a and KAV-250aJ3 require at least two inches (5 cm) of clearance each side and at least two inches (5 cm) of clearance above the com[...]

FIGURE 1 THE KAV-250a FRONT PANEL 1 2 1 Power Button 2 Power LED[...]

Front Panel Description: KAV-250a See Figure 1 on page 4 1 Power Button Use this button to turn the KAV-250a power on and off and also to switch the 12 VDC output (12 V trigger) on and off. 2 Power LED The blue power LED illuminates when the amplifier is on. KAV-250a and KAV-250a/3 Amplifiers 5[...]

FIGURE 2 THE KAV-250a BA(;K PANEL 5 11 12 10 13 Balanced Inputs 3 Right Input 4 Left Input (Bridged) Single-ended Inputs 5 Right Input 6 Left Input (Bridged) Amplifier Channel Outputs 7 Right Output (Bridged-) 8 Left Output (Bridged+) Fuses 9 AGC~ Fuses 10 Line Fuse Remote Controls 11 12 VDC Remote Power Out 12 12 VDC Remote Power In Power 13 IEC P[...]

Back Panel Description: KAV-250a See Figure 2 on page 6 The KAV-250a back panel provides connections for all inputs and outputs, remote control input and output links, and AC power supply. Inputs and outputs labeled left and right are on the left and right side of the amplifier, respectively, when viewing the amplifier from the front panel. Balance[...]

Back Panel Description, continued Remote Controls 11 12 VDC Remote Power Out 12 12 VDC Remote Power In The KAV-250a is equipped with an output that sends 12 VDC power on/off (12 trigger) signals to other Krell components and other devices that incorporate 12 V trigger. This allows you to turn the KAV-250a on and off using a Krell or other component[...]

FIGURE 3 THE KAV-250a/3 FRONT PANEL 14 15 14 Power Button 15 Power LED[...]

Front Panel Description: KAV-250a/3 See Figure 3 on page 9 14 Power Button Use this button to turn the KAV-250a/3 power on and off and also to switch the 12 VDC output (12 V trigger) on and off. 15 Power LED The blue power LED illuminates when the amplifier is powered on. 10 KAV-250a and KAV-250a/3 Amplifiers[...]

FIGURE 4 THE KAV-250a/3 BACK PANEL 16 19 17 2o 18 21 25 22 25 23 25 24 27 28 26 29 Balanced Inputs 16 Right Input 17 Center Input 18 Left Input Single-ended Inputs 19 Right Input 20 Center Input 21 Left Input Amplifier Channel Outputs 22 Right Output 23 Center Output 24 Left Output Fuses 25 AGC e~Euses ~-----’~ 26 Line Fuse Remote Controls 27 12 [...]

Back Panel Description: KAV-250a/3 See Figure 4 on page 11 The KAV-250a/3 back panel provides connections for all inputs and outputs, remote control input and output links, and AC power supply. Inputs and outputs labeled left and right are on the left and right side of the amplifier, respectively, when viewing the amplifier from the front panel. Ba[...]

Back Panel Description, continued Note Fuses must be replaced with the fuse value specified on the KA V-250a/3 back panel Use a 20 amp slow-blow line fuse for 100/120 V systems or a 12 amp slow-blow line fuse for 220/240 V systems. Remote Controls 27 12 VDC Remote Power Out 28 12 VDC Remote Power In The KAV-250a/3 is equipped with an output that se[...]

Connecting the KAV-250a or KAV-250a/3 Amplifier to Your System INPUT AND OUTPUT CONNECTIONS The following steps describe how to connect cables to the KAV-250a or KAV-250a/3 amplifier. 1. Neatly arrange and organize the wiring to and from the amplifier and all components. Separate AC wires from audio cables to prevent hum or other unwanted noise fro[...]

Optional System Configurations The KAV-250a and KAV-250a/3 can be reconfigured for either Multi Amp Throughput (MAT) or bridged operation. IMPORTANT Removing the cover to reconfigure for MA T or for bridged operation is the ONL Y instance you are authorized to remove the cover of ANY Kre// component without voiding your Warranty. For more informati[...]

FIGURE 5 RECONFIGURING THE KAV-250a FOR MAT OR BRIDGED OPERATI( tN PC boards showing MAT jumper configuration Left Right PC boards showing bridged jumper configuration Left Right Power supply PC boards Right 16 KAV-250a and KAV-250-a/3 Amplifiers[...]

Reconfiguring the KAV-250a for MAT See Figure 5 on page 16 Tools needed: T-15 Torx wrench and one ribbon connection cable 1. Turn the KAV-250a off by pressing the power button (1) on the front panel. The blue power LED (2) extinguishes. Unplug the AC power cord from the IEC power connector (13) on the back panel. 2. Using the T:15 Torx wrench, remo[...]

5. Connect one end of the second ribbon connection cable to jumper pin J4 on the center amplifier channel. Connect the other end of this ribbon connection cable to jumper pin J5 on the right amplifier channel. 6. Replace the cover (slide the front panel end in first). Using the T-15 Torx wrench, secure the 12 screws. The KAV-250a/3 amplifier is now[...]

FIGURE 6 RECONFIGURING THE KAV-250a/3 FOR MAT OR BRIDGED OPERATION PC boards showing MAT jumper configuration PC boards showing bridged jumper configuration (See Option 1, on page 21) PC boards showing bridged jumper configuration (See Option 2, on page 21) Left Center Right Power supply PC boards ht KAV-250a and KAV-250-a/3 Amplifiers 19[...]

BRIDGED OPERATION The KAV-250a and the KAV-250a/3 can be reconfigured for bridged operation. When the KAV-250a amplifier’s channels are bridged, the amplifier’s output power is quadrupled: the amplifier delivers 1,000 Watts to an 8 Ohm load. The KAV-250a/3 can be reconfigured to bridge any two of its three amplifier channels to operate as one c[...]

IMPORTANT When operating the amplifier in bridged mode and using an output device with single-ended RCA cables, be sure to remove the shorting pin from the/eft balanced XLR input (4). Reconfiguring the KAV-250a/3 for Bridged Operation See Figure 6 on page 19 Tools needed: T-15 Torx wrench and two ribbon connection cables 1. Turn the KAV-250a/3 off [...]

2. When the center and right amplifier channels are bridged (Option 2), connect the output cable from the output device to the right balanced XLR (16) or single-ended RCA (19)input. Connect the positive loudspeaker lead (red) to the positive binding post on the (right) amplifier channel (22). Connect the negative loudspeaker lead (black) positive b[...]

Examples of Connection Scenarios, continued Power Biamplification (Stereo, 2-channel) Power biamplification uses the MAT feature of the KAV-250a to send the same music signal to all amplifier channels using one balanced or single-ended input connection. When the KAV-250a is reconfigured for MAT, one channel of the amplifier powers the Ioudspeaker?[...]

Examples of Connection Scenarios, continued Multi Power Mode Multi power mode uses the KAV-250a/3’s MAT feature to independently power multiple pairs of stereo loudspeakers to extend the listening environment throughout your home. When the KAV-250a/3 is reconfigured for MAT, each channel powers an individual loudspeaker, with one KAV-250a/3 dedic[...]

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. Press the KAV-250a power button (1) or KAV-250a/3 power button (14) on amplifier’s front panel. Wait until the blue power LED (2) on the KAV-25[...]

Amplifier Troubleshooting HOW TO TROUBLESHOOT SYSTEM NOISE When you mix and match audio components, each with its own ground potential, a low frequency hum may occur in one or both loudspeakers. This often occurs when introducing a new component into a system. If a low frequency hum emanates from the loudspeakers when you place the KAV- 250a stereo[...]

Question and Answer Q. Should I leave the KAV-250a or KAV-250a/3 amplifier on at all times? A. No. These amplifiers do not have a stand-by mode. Leaving them on at all times would result in considerable heat output and power consumption. For best results, turn the amplifier off when not in use, and allow a five minute warm-up after it is turned on.[...]

Warranty The KAV-250a and KAV-250a/3 amplifiers have. a limited and transferable warranty of five years for parts and labor on cimuitry. Should this product fail to perform at any time during the warranty, Krell will repair it at no cost to the owner, except as set forth in this warranty. This warranty does not apply to damage caused by acts of God[...]

Return Authorization Procedure If you believe there is a problem with your component, please contact your dealer, dis- tributor, or the Krell factory to discuss the problem before you return the component for repair. To expedite service, you may wish to complete and e-mail the Service Request Form in the Service Section of our website at: http://ww[...]

Specifications KAV-250a Stereo Amplifier FREQUENCY RESPONSE SIGNAL TO NOISE RATIO "A" WEIGHTED TOTAL HARMONIC DISTORTION (THD) GAIN INPUT IMPEDANCE INPUT SENSITIVITY OUTPUT VOLTAGE OUTPUT POWER, EACH CHANNEL DRIVEN BRIDGED POWER CONSUMPTION INPUTS OUTPUTS DIMENSIONS WEIGHT 20 Hz to 20 kHz +0 dB, -0.1 dB 0.4 Hz to 170 kHz +0 dB, -3 dB 118d[...]

KAV-250a/3 Three-Channel Amplifier FREQUENCY RESPONSE 20 Hz to 20 kHz 0.4 Hz to 112 kHz SIGNAL TO NOISE RATIO "A" WEIGHTED TOTAL HARMONIC DISTORTION (THD) GAIN INPUT IMPEDANCE INPUT SENSITIVITY OUTPUT VOLTAGE OUTPUT POWER, EACH CHANNEL DRIVEN BRIDGED POWER CONSUMPTION INPUTS OUTPUTS DIMENSIONS WEIGHT +0 dB, -0.2 dB +0 dB, -3 dB 118dB 1 kH[...]

Krell Industries, Inc. 45 Connair Road Orange, CT 06477-3650 USA TEL 203-799-9954 FAX 203-799-9796 E-MAIL krell@ krellonline.com WEBSITE http://www.krellon line.corn KAV-250a Stereo Power Amplifier KAV-250a/3 Three-Channel Power Amplifier[...]