Krell Industries KBL User's Manual
Contents
1. Ee Pure ie Pa ora renin See see e z So ae z a A Ea a A a iS O Fe AE A 3 KBL KPA OWNERS MANUAL Roa 45 Connair Road Orange CT 06477 0533 USA a AS rere Se pee es ai KBL KPA OWNERS MANUAL Thank you for your purchase of a new KRELL preamplifier This Owners Manual covers both the KBL and KPA preamplifiers as they have been designed to be companion pieces and can be utilized in varying combinations For each user there will be information that does not pertain to their specific situation Therefore in the interest of clarity details relating to different combinations are presented in well defined sections The KBL and KPA represent significant departures from traditional preamplifier design The time invested in carefully reading this manual will yield an important understanding of the functions and design features of the units Due to the high level of performance of which these units are capable careful placement and installation are crucial Your thorough understanding of the operations of the KBL and KPA will help insure their maximum performance and long life AB THE ERS AL The KBL KPA Owner s Manual is divided into various groups of information The purpose of the document as a whole is to familiarize you with the units and guide you through their set up installation and operation in a logical progression The Table of Contents is as follows B General Information a description2. C UNPACKING Remove the units from the shipping container Keep the shipping materials in a safe dry place for future use The following is a list of the materials that are included in the packaging 1KBL 1 each preamplifier chassis KBL power supply with DC cable installed AC line cord T shaped Allen driver Spare fuse for the power supply Owner s Manual LKBL amp 1KPA packed together 1 each KBL amp KPA preamplifier chassis a KBL power supply with DC cable installed AC line cord DC jumper cable KBL to KPA T shaped Allen driver Spare fuse for the power supply Owner s Manual IKPA without power supply 1 each preamplifier chassis DC jumper cable KBL to KPA T shaped Allen driver Owner s Manual LKPA with power supply 1 each preamplifier chassis KPA power supply with AC and DC cables attached DC jumper cable KBL to KPA not used when the dedicated KPA supply is used T shaped Allen driver Owner s Manual Inspect the unit s and power supply s for damage If any is evident or if some of the accessories are missing contact your dealer or the factory immediately If everything is in order you can proceed with the next steps D INSTALLATION 1 Cautions Note These are important points of which you should always be aware They are presented before the actual installation procedures should you not read through the Manual entirely a When installing the KBL always connect the DC cable betwee
3. The LED indicator will illuminate when the switch is in any position other than flat This switch can be operated while listening to the KPA at normal levels without risk of damage to the preamplifier amplifier s or speakers Its setting is a matter of personal taste 2 KBL Functions a Select Use the Select switch to choose between the various source playback components for listening Be sure to lower the volume when switching among components as large differences in level between sources can gt cause damage to other components The Select switch is also used to choose the signal to be sent to the tape recorders via the Record outputs When two KBLs are used in dual mono both Select switches must be set the same There is a Mute function at the 12 o clock position that should be used when source material is being changed or when source components are being turned on and off and at the completion of each listening session Note Components that are not being listened to should be turned off or have their volume turned down For instance a tuner should be turned _ off or have its volume lowered while it is not being listened to b Monitor Use the Monitor switch to listen to the playback from a recording device This can be done while the recording is in process such as with three head tape recorder or during playback only The inputs available on the Monitor switch are S 1 and B 2 These are wired in parallel to
4. accommodate the latest evolutions of preamplifier circuitry and functions These units are the current state of the art No compromise was allowed in their design Details concerning their technical performance are covered in more detail below A second important consideration was to introduce the programmable concept employed in our current KSA KMA amplifier line into our preamplifier line A single KBL and KPA are used for stereo operation A second unit of either can be added to achieve dual mono fully balanced operation They can be easily changed without being returned to the factory There are many advantages to dual mono operation The capability of the KBL and KPA to operate in either mode allows you to plan the development of your system over time without the waste of money and time associated with trading or selling used gear It also allows you to optimize your system more closely to your needs For example if line sources are most important you can purchase two KBLs with or without a KPA If phono is most important you can purchase two KPA s and one KBL creating a completely balanced path for the phono signal The ultimate configuration of course is two KBL and two KPA This creates a completely dual mono balanced preamplifier system for all inputs and outputs Other details concerning the functions of the units are covered below and in the Installation and Operation sections The method used to switch a KBL or KPA from stereo
5. extension cords or multiple outlet adapters AC extension cords outlet strips and good quality surge protectors that are rated for 15 amps and grounded are acceptable 10 d Power ly Installation 1 Place the power supply s in location 2 Connect the DC cable s from the supply s to the il 3 Plug the DC jumper between the KBL s and KPA s 4 Do not plug the AC connector s into the mains at this time 7 Connection of Inputs and Outputs All source components and amplifiers should be off at this point When connecting balanced components to the KBL via RCA connectors be sure to maintain proper polarity of the non inverted and inverted inputs The non inverted inputs are the Left connectors on the top row the inverted inputs are the Right connectors on the bottom row Also if you are using two KBL in dual mono remember that the Left XLRs are operational and the Right XLR connectors are disabled a Connection of Input Sources nec ic nofth A In Either input can accommodate a moving magnet or moving coil cartridge Single KPA connect the ill outputs to the KPA inputs 1 amp 2 in the conventional manner Dual KPA balanced input wiring from the cartridge s connect the high left white right red output from the cartridge to the left input connectors on the KPAs Connect the low left blue right green to the right input connectors on the KPAs Typically the top unit is used for the left channel an
6. KBL when operated in dual mono Used for both inputs and the Main output of the KPA when used in dual mono Can be used between two KPAs and two KBLs operating in dual mono d Balanced RCA to XLR Termination uses two conductor coaxial cable See drawing 2 at the rear of the Manual for details 2 prs RCA and 1 pr XLR connectors are used on each pair of audio cables The XLR end uses the termination detailed in section b above the RCA end uses the termination detailed in section c above Pin 2 on the XLR is the non inverted signal and is soldered to the red RCA Pin 3 on me XLR is the inverted signal and is soldered to the white RCA Can be used between two KPA and two KBL operating in dual mono e Balanced KPA Input Termination uses two conductor coaxial cable See Drawing 3 at the rear of the Manual for details 2 prs of RCA connectors are used for each cable 4 prs total This is a special termination that allows for a balanced input from the cartridge to two KPAs There is no other use for this termination i I Read the portions of sections a and b below that pertain to your system for the specific cable terminations required If you are adding to your system you may need to change some cable terminations to take full advantage of dual mono balanced operation a System Configuration Terminations One KBL B 1 B 2 male b S 1 S 2 S 3 S 4 male a Record 1 amp 2 male a Main on RCA male a Main on XLR
7. a Standard RCA Termination uses either coax cable or two conductor coaxial cable Center pin audio signal Outer ring ground when using two conductor coax cable one center conductor is connected to the outer ring at both ends the shield is connected to the outer ring at only one end This end should be marked and used at the input end of the cable For example this end would go to the amplifier when the cable is run from preamp to amp Used for all RCA inputs and outputs on the KPA and the KBL when operated with single ended components b Standard XLR Termination as two conductor coaxial cable Pin 1 ground Pin 2 non inverted signal also called 0 or signal Pin 3 inverted signal also called 180 or signal Used on inputs B 1 B 2 and Main Output of the KBL when used in either stereo or dual mono All Krell Industries and Krell gt products use this pin out for inputs and outputs c Balanced RCA Termination uses two conductor coaxial cable See Drawing 1 at the rear of the Manual for details 1 pr of RCA connectors are used on each end of the cable with this termination 4 prs total are used if this termination is used at both ends Red RCA Center pin first cable center conductor 0 or White RCA Center pin second cable center conductor 180 or Outer Ring both RCA shield from around the two center conductors Used for inputs S 1 8 2 S 3 S 4 Record Outputs and the Main output of the
8. of the basic design and performance features of the KBL and KPA C Unpacking detail of accessories shipped with the KBL and KPA in various configurations D Installation 1 Caution 2 Connector Details 3 Connector Termination Types 4 Cable Requirements for Inputs and Outputs 5 Setting of Internal Switches 6 Unit Location Guidelines and Installation 7 Connection of Inputs and Outputs 8 Turn on of the Preamplifiers 1 2 KPA Functions KBL Functions E Operation G Termination Drawings SERIAL NUMBERS amp FACTORY SHIPPED CONFIGURATIO KBL preamplifier serial number was shipped from the factory set up for ___ stereo operation dual mono operation Please refer to information specific to this mode of operation throughout the manual Should you wish to dl between stereo and monaural operation please refer to section D 5 This is only necessary when changing either unit from stereo to mono operation All KPA are shipped from the factory set up for stereo operation Please refer to section E 1 d for information regarding dual mono operation B GENERAL INFORMATION The KRELL KBL Krell Balanced Line and KPA Krell Phono Amplifier present many new concepts in preamplifier design The traditional preamplifier contains both a phono section and a line section The KBL and KPA divide these functions into two separate units This was done for several reasons The primary motivation was to allow adequate space to
9. the same inputs on the Select switch 14 Input B 2 on the Monitor switch uses only the non inverted signal Therefore if you are feeding a balanced signal into B 2 there will be a 6 dB difference in level between B 2 on the Select switch and on the Monitor switch The level on the Select switch will be the higher one Note Be careful not to create a feedback loop between the KBL an tape recorder This can happen by selecting the tape recorder output on the Select switch and having the tape recorder set on source This set up takes the output of the tape recorder to the KBL through the Record output back to the tape recorder inputs and out the tape recorder outputs to the KBL again When doing Tape Source comparisons always use the Monitor switch for the tape recorder output and do the Tape Source switching on the tape recorder c Gain Use the Gain switch to adjust the overall gain of the KBL The Low position is 9 dB of gain the High position is 15 dB The LED indicator is illuminated when the switch is in the High position The switch can be changed during listening at low and moderate listening levels During high level listening it is advisable to lower the volume before adjusting the switch d Phase Use the Phase switch to reverse the absolute phase of the Main outputs The switch is functional for both the single ended and balanced outputs The LED indicator is illuminated when the switch is set for ROS reversal W
10. to dual mono operation is unique For stereo operation each chassis has complete circuit paths for the left and right channels When switched to dual mono balanced operation the left channel circuitry is assigned to the non inverted path and the right channel circuitry is assigned to the inverted path This changes the rear panel connector assignments on both the KBL and KPA See the sections on Installation and Operation below for more details The KBL and KPA use high bias pure Class A circuits throughout including the power supplies and regulators Circuits are DC coupled meaning there are no capacitors in the signal path The power supply system and output circuits are extremely high power when compared with conventional preamplifier designs The output section of the KBL for example is really a small power amplifier capable of swinging 60 volts peak to peak This allows the KBL to maintain exceptional linearity under all conditions and drive virtually any length of cable without signal degradation The external supply has two stages of regulation Within each preamp chassis there are independent tracking regulators for each section of circuitry separated channel to channel The KPA has completely passive RIAA equalization Maximum deviation from the standard is 1 dB from 10Hz to 20KHz All parts are 1 tolerance Both preamplifiers have innovative operational features The KBL has two balanced inputs and one set of bala
11. be disabled if desrei See section D 5 above for details on turning off the LEDs f Level Use the level control to adjust the listening level When two KBLs are used the level controls on the two preamps also control the balance between left and right channels F WARRANTY The KBL and KPA have a limited warranty of five years from the date of purchase Please return completed warranty cards for each unit immediately after successful installation and operation are completed The warranty for all Krell product is valid in the country to where it was originally shipped and at the factory If there are problems with your unit s please contact your dealer or the factory immediately Should your unit need to be repaired contact the factory or your distributor for a return authorization Freight to the factory or distributor is your responsibility Return freight to you will be perg by the factory or distributor 9 11 90 gt 16 Balanced RCA to RCA cable wiring diagram Drawing 1 Termination c WHITE non inverting solder to white RCA center pin BLACK inverting solder to red RCA center pin N S SHIELD wire solder to white non inverting RCA case N a a SHIELD wire solder to red inverting RCA case solder extra wires to shield for RCA ground solder extra wires to shield for RCA ground 5 SHIELD wire solder to red inverting RCA case AA SHIELD wire solder to white non inverting RCA case e BLACK inve
12. ches should be set to Mute position and the KBL volume control s should be fully counterclockwise Connect the KBL and KPA Gif a separate supply is being used for the KPA power supply s to the AC mains at this point The LED s on the power supply s and on the preamplifier front panel s should now illuminate None of the other LEDs should be illuminated at this point b Future Use The KBL and KPA are designed to be on at all times In other words they are not intended to be routinely switched on and off The only times it is recommended to turn the units off is when your system will be left unattended for a long period of time such as during a vacation or a business trip In these cases all other equipment should be turned off and the KBL KPA power supply s should be disconnected from the AC mains When you return re connect the supply s to the AC mains before turning on other equipment This procedure should also be followed if you reorganize your system and need to change the wiring of the supply s to the preamps 12 E OPERATION 1 KPA Functions a Select Use the Select switch to choose between two different cartridges or tonearms If the two inputs are not the same type cartridge be sure to change the gain with the Gain switch to avoid any overload conditions See section c below b Loading Use the Loading switch to adjust the impedance load for the selected cartridge input This can be adjusted while listeni
13. d the bottom unit is used for the right channel The output of the KPA is high level input and can be sent to any input on the KBL s Connect the output of the KPA s to the KBL inputs at this time 2 ion of KBL In The inputs of the KBL have not been labeled with specific component names so you can set up the Select switch pattern to your preference B 1 and B 2 refer to Balanced inputs 1 amp 2 S 1 S 2 S 3 S 4 refer to Single ended inputs 1 through 4 Once you have decided which component will be assigned to which input proceed with connecting the source components to the desired inputs 11 b Connection of KBL Record Outputs There are two Record outputs which receive the signal from the input chosen on the Select switch for sending to two tape recorders The two outputs are wired in parallel and have no relation to any of the inputs Make the connections between the Record outputs and tape recorders at this time C nnection of the KBL Main There are two sets of Main outputs one set single ended on RCAs one set balanced on XLRs They are wired in parallel and can be connected and operated simultaneously They are provided to drive two independent systems from one preamplifier Make the connections between the Main outputs and amplifier s and or crossovers at this time n on of the Preamplifi a Initial Turn On All source components and amplifiers should be off at this point The KPA and KBL Select swit
14. ectors are disabled All RCA connectors remain operational but with different functions See section D3 Connector Terminations below for details b KBL Indicator LED switch The Symmetry LEDs on the KBL can be disabled Their function is unrelated to stereo or mono operation The switch located just forward of SW8 in the right rear of the unit controls this function Positions 1 amp 2 depressed allow the LEDs to light Both switches depressed to Open disable the LEDs 6 Unit Location Guidelines and Installation Before installation of your KBL KPA s and power supply s we recommend that you follow these guidelines in choosing proper locations for the units This will help insure a trouble free installation and maximum performance of the preamps All associated equipment should be turned off at this point a Preamplifier Location Guidelin 1 The KBL and KPA measure 19 wide 13 deep 2 5 high 2 Four inches clearance should be allowed above the top of either the KBL or KPA Only a small amount of clearance is needed on the sides Four to six inches clearance should be allowed at the rear of either unit to provide for cables 3 The units can be stacked KPA s should be placed on the bottom with KBL s on top 4 KPA s are sensitive to induced hum from motors or power supplies In general they should be located at least one foot from other components with the exception of the KBL In particular power supplies ta
15. female b Te dto FDA eee A E ee A UA ee A da Pi AU a e di a ee A ee ee ee PA ee O es E a A ee A Sd A E A ee SAPO ee A ees ee ee ee A O eee eee ee eee oe One KPA 1 amp 2 Main male a Unit s Inputs Outputs Terminations Two KBL B 1 amp B 2 male b S 1 S 2 S 3 S 4 c Record 1 amp 2 c Main on RCA c Main on XLR female b Only the left connectors are operational in dual mono the right connectors are disabled Two KPA 1 amp 2 e Two KPA Main c b fi A l r n Unit s rminati One KPA to one or two KBLs a both ends Two KPAs to one or two KBLs c both ends Qr Two KPAs to one or two KBLs d w male XLR KBL end 5 in r i Please read this section to determine if you have the need or desire to change the internal switches a KBL Stereo Dual Mono switches These switches are used to change the KBL between stereo and mono operation Their most common use is to change an existing KBL from stereo to dual mono when installing a second KBL for dual mono There is one double toggle two position dip switch between the input connectors for B 1 SW6 and for B 2 SW7 there is a third near the balanced output connectors SW8 All three switches must be sei the same They are not to be set in any other combination Positions C2 amp C4 depressed are for stereo operation Positions C1 amp C3 depressed are for mono operation In dual mono operation only the left XLR connectors are operational the right conn
16. hen two KBLs are used the Phase switch on one KBL can be used to reverse the phase of one channel in relation to the other Many recordings have had their overall phase reversed during the various processing stages When the absolute phase and phase relationship between channels is correct there are improved transients and dynamic detail e metr 1 One KBL Operating in Stereo When a single KBL is used for stereo operation the function of the Symmetry control is like a conventional balance control Use it to adjust for small level differences between channels There are four 1 dB steps of attenuation and an Off position for each channel 15 When the control is turned clockwise the left channel is attenuated when turned counterclockwise the right channel is attenuated The LED indicators may illuminate at high listening levels This indicates that a level difference exists between the left and right channels at that moment This can be disregarded unless there is an audible channel imbalance 2 Two KBL Operating in Dual Mono When two KBL are used for dual mono operation the Symmetry control adjusts for differences in level between the non inverted and inverted outputs When there is an imbalance between the two outputs one of the LEDs will illuminate to indicate the output that is lower in level Turn the control in that direction until the LED goes out This may or may not occur in both channels at the same time The LEDs can
17. n the preamp chassis and the power supply before plugging the power supply into the AC mains b When installing a KBL KPA combination always connect the DC cables between the KPA and the KBL and between the power supply and the KBL before plugging the power supply into the AC mains disconnect the AC from the mains_before disconnecting the DG cable s from the preamp s d le KPA can r in balanced m The Balanced AS should not be activated unless two KPA are used e These points are true for both the initial installation of the KBL or KPA and for revisions of your system that require their relocation 2 Connector Details This section with sections 3 amp 4 below presents all details necessary to make or modify cables for use with all combinations of the KBL and KPA After reading these sections check all the cables you intend to use to make sure they are appropriate for your installation a General Information Different configurations of the KBL and KPA require different cable terminations The connector assignments for the KBL and KPA inputs and outputs are given b KBL Connector Assignments B 1 B 1 female 3 pin XLR S 1 S 2 S 3 S 4 female RCA Record Outputs 2 sets female RCA Main Outputs 1 set on female RCA 1 set on 3 pin male XLR c KPA Connector Assignment All are female RCA 3 Connector Termination Types For all terminations Make sure wire color and pin numbers match at both ends of the cable
18. nced outputs in addition to four single ended inputs and one set of single ended outputs This allows one KBL to accommodate balanced line sources and amplifiers which Krell believes to be the standard for high end audio gear Therefore it is only necessary to purchase a second KBL to achieve dual mono fully balanced operation The KBL input labeling is a departure from the norm as well Instead of the conventional phono tuner tape aux etc we have labeled the inputs B 1 B 2 S 1 S 2 S 3 S 4 These refer to Balanced Input 1 Balanced Input 2 Single ended Input 1 etc Components in audio systems today are unpredictable This input labeling allows KBL Selector can to be e or changed by each user to create the order he desires The KBL has front panel adjustments for output gain and absolute phase The Gain switch provides a course adjustment to compensate for systems of different efficiencies and for level differences in source components The KPA has inputs for two different cartridges There is a front panel switch to adjust between the gains required for moving coil and moving magnet cartridges Adjustment for cartridge impedance loading is on the front panel as well Perhaps the most interesting features on the KPA are the front panel adjustments for high and low RIAA trim These allow you to tailor the RIAA equalization to specific records in small increments Single ended Balanced switching are also on the front panel
19. ng with the KBL or preamp volume at normal levels without causing damage to any other component The correct load for any cartridge is a matter of personal taste Start by setting the control to the load recommended by the manufacturer Evaluate the sound at this and several other settings Experiment until you determine the setting for the most desirable sound quality c Gain Use the Gain switch to change the KPA between moving coil and moving magnet gain The LED indicator will illuminate when the unit is set for moving magnet gain The s h 1 1s in its M 1tion d Balanced The Balanced switch is used to change the unit from stereo to dual mono operation balanced when two KPAs are being used To activate Balanced operation put the Select to its Mute position and then engage the Balanced switch The LED indicator will illuminate when the unit is set for balanced operation O onerata a duano cannot be used with one KPA e RIAA Adjustment 20 Hz Use this switch to make subtle adjustments to the low end of the RIAA equalization curve The LED indicator will illuminate when the switch is in any position other than flat 13 This switch can be operated while listening to the KPA at normal levels without risk of damage to the preamplifier amplifier s or speakers Its setting is a matter of personal taste f IAA Adi ment 20 KH Use this switch to make subtle adjustments to the high end of the RIAA equalization curve
20. pe recorders and turntables should be more than a foot away from the KPA s b Preamplifier Installation Place the preamplifier s in position Check that all cable lengths are adequate at this point c P r ly L ion Guidelin 1 The KBL supply measures 9 75 wide 12 deep 2 25 high The KPA supply measures 7 25 wide 7 75 deep 2 5 high Only KPA not powered from a KBL have a separated supply 2 Six foot AC and DC cables are provided with the supply s Plan the respective position of the supply s and preamplifier s within these distances Allow at least a small amount of cable to be excess SO neither cable is pulled tight Contact the factory if the DC cable is too short Any attempt to extend it jeopardizes the power supply and the preamp and will void the unit s warranty 3 Although well shielded the power supply s should not be laced close to hum sensitive components such as turntables phono preamps or tape recorders 4 Allow ample air space around the supply s for heat dissipation Five inches on top and two inches on each side is adequate Two supplies should not be placed directly on top of each other They should be placed side to side 5 The KBL or KPA supplies do not require that an ACV circuit be dedicated for their use They should be connected to a 15 or 20 amp circuit that is dedicated for the source components and the preamplifiers Do not connect them to the mains with light gauge 18 or higher
21. rting solder to red RCA center pin oO a WHITE non inverting solder to white RCA center pin Balanced RCA to XLR cable wiring diagram Drawing 2 Termination d BALANCED RCA END WHITE non inverting solder to white RCA center pin BLACK inverting solder to red RCA center pin SHIELD wire solder to white non inverting RCA case SHIELD wire solder to red inverting RCA case solder extra wire to shield for XLR ground a SHIELD wire ground solder to pin 1 on ALR BLACK inverting solder to pin 3 on XLR WHITE non inverting solder to pin 2 on XLR Balanced KPA cable wiring diagram Drawing 3 Termination e BALANCED KPA END WHITE non inverting solder to RCA center pin t ee BLACK ERAS solder to RCA center pin SR SHIELD wire solder to non inverting RCA case SHIELD wire solder to inverting RCA case solder extra wires to shield for RCA ground solder extra wire to shield for ground a My Keep seperate from RCA case o Je to Turntable ground OS if necessary woe r ral er BLACK inverting solder to RCA case ae WHITE non inverting solder to RCA center pin Ae A maama A hte Air rene Pare rd a JR py SB a TURNT ABLE END
Download Pdf Manuals
Related Search