owner’s manual X-Rack XR-20 XR-24 rack mount mixers
Important precautions 1 Save the carton and packing materials! Should you ever need to ship the unit, use only the original factory packing. For replacement packaging, call Crest Audio’s Customer Service Department directly. 2 3 Read all documentation before operating your equipment. Retain all documentation for future reference. Follow all instructions printed on unit chassis for proper operation. Service Information Do not open unit! Opening the unit will expose you to potentially dangerous voltages.
IMPORTANT SAFETY INSTRUCTIONS WARNING: When using electrical products, basic cautions should always be followed, including the following: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. Read these instructions. Keep these instructions. Heed all warnings. Follow all instructions. Do not use this apparatus near water. Clean only with a dry cloth. Do not block any of the ventilation openings. Install in accordance with manufacturer’s instructions.
table of contents Introduction Thank you and congratulations on your purchase of your new Crest Audio X-Rack mixer. We’re confident that you will enjoy many years of trouble-free service from it. You will quickly find that it fits into a wide variety of mixing applications with ease.
XR-20/24 block diagram JIMI XR-20 / XR-24 owner’s manual p.
how to use this manual format This manual uses a format that is intended to be easy to read, yet technical for those who need to know all the details. For feature descriptions, this is done by devoting the left side of each page to 1) an overall module picture, 2) a block diagram, and 3) a control closeup. These images all pertain to the features and control descriptions on the right side of the page.
1 Mono input channel XR-20 / XR-24 owner’s manual Module Controls Block diagram +48V ON +48V BAL MIC IN LINE GAIN 12 - 70 dB HPF 70Hz -18dB/Oct HPF BAL LINE IN 27dB PAD p.
Mono Input channel 1 Front panel features Mono Input channel features are identical for both the XR-20 and the XR-24. The XR-20 has 12 Mono inputs and the XR-24 has 8 Mono inputs. Line Input (mic pad) The input preamp circuit is set up to accept a mic-level signal. This signal is brought in via the XLR mic-input connector located on the rear panel. The 1/4" TRS input jack is disabled.
1 Mono input channel XR-20 / XR-24 owner’s manual Module Controls Block diagram LEVEL FREQ LEVEL FREQ LEVEL LEVEL HI MID 400 - 8 KHZ HF 12 KHZ EQ ON LF 80 HZ LOW MID 80 - 2 KHZ FOUR BAND EQ p.
Mono Input channel 1 Front panel features EQ Many audio signals coming into the console require some degree of corrective eq in order to be part of a good sounding mix. XR-20 & XR-24 offer a very useful and great sounding eq section on each channel. The input EQ consists of four bands: High, High-mid, Low-mid and Low. The High and Low frequency bands each have a boost/cut control and their frequencies are fixed. The High-mid and Lowmid bands each have variable boost/cut and variable frequency.
1 Mono input channel XR-20 / XR-24 owner’s manual Module Controls Block diagram MUTE EQ ON HF 12 KHZ PAN CHAN FADER MONO L-R G1-2 G3-4 FADER AMP BUS ASSIGN SWITCHES +10 100MM YES PRE SOURCE MUTE ? A1-2 PRE PAN 1-2 LEVEL 1-2 A1 A2 PRE EQ NO PRE FADER A3-4 PRE PRE-SOURCE BUFFER PRE INSERT PRE-SOURCE SELECT LEV 3 LEV 4 A5-6 PRE LEV 5 LEV 6 AUX SENDS 1 THRU 6 p.
Mono Input channel 1 AUX send features Six auxiliary sends are available for creating individual output mixes. These can be used to drive effects processors, provide monitor mixes, create broadcast or alternate sound reinforcement mixes, or for other special requirements. Note: The default PRE setting for the Auxes is pre-fader, but post-mute, post-insert, and post eq.
1 Mono input channel XR-20 / XR-24 owner’s manual Module Controls Block diagram PFL SOLO LEFT SOLO RIGHT TO PEAK CIRCUIT SOLO DC MUTE EQ ON PAN CHAN FADER MONO L-R G1-2 G3-4 FADER AMP BUS ASSIGN SWITCHES +10 100MM YES PRE SOURCE MUTE ? A1-2 PRE PAN 1-2 LEVEL 1-2 A1 A2 PRE EQ NO PRE FADER A3-4 PRE PRE-SOURCE BUFFER PRE-SOURCE SELECT LEV 3 LEV 4 A5-6 PRE LEV 5 LEV 6 AUX SENDS 1 THRU 6 p.
Mono Input channel 1 Bus assignment features The bus assignment section offers considerable flexibility for creating what eventually becomes the main output mix. Two stereo subgroups are available for creating submixes or separate stereo mixes. All assignments are derived post-fader, post-eq, and post-mute. PAN control The pan control positions the signal within the stereo left/right (or odd/even) field.
1 Mono input channel XR-20 / XR-24 owner’s manual Connectors Rear panel Block diagram HPF 70Hz -18dB/Oct GAIN 12 - 70 dB BAL MIC IN LINE HPF BAL LINE IN INPUT PREAMP 27dB PAD INSERT SEND / RTN POST FADER DIRECT OUT SOURCE DIRECT OUT GC PRE FADER REAR PANEL X-RACK MONO INPUT MODULE 12 OR 8 MO NO INPUTS AVAILABLE PFL SOLO LEFT +48V ON +48V SOLO RIGHT GAIN 12 - 70 dB BAL MIC IN LINE TO PEAK CIRCU IT HPF 70Hz -18dB/Oct LEVEL FREQ LEVEL FREQ LEVEL LEVEL PAN EQ ON LF 80 HZ HPF LOWMID 80 -
Mono Input channel 1 Rear panel features 48 V Phantom power 48 volts DC is applied to pins 2 and 3 on the mic-input XLR connector.This option is used with condenser microphones and active direct boxes that require an external DC voltage (phantom power ) in order to operate. Line INPUT jack Line-level signals, balanced or unbalanced, may be brought into the input channel through this jack. The LINE INPUT switch must be pressed for this jack to be active.
1 Stereo input channel XR-20 / XR-24 owner’s manual Controls Module Block diagram +48V ON +48V BAL MIC IN LINE GAIN 15 - 60 dB MONO BAL LEFT BAL LINE IN 27dB PAD PRE EQ BAL MIC IN RIGHT INPUT SIGNAL LED BAL LINE IN 27dB PAD INPUT PREAMP PEAK R (PFL) SIG p.
Stereo Input channel 1 Front panel features Stereo Input channels features are identical for both the XR-20 and the XR-24. The XR20 has 4 Stereo inputs, and the XR-24 has and 8 Stereo inputs. On both models the Stereo inputs are located to the left of the master section, to the right of the Mono inputs. They can be treated as mono input channels, or as Stereo input channels. Stereo Line Input (mic pad) The stereo input preamp circuit is set up to accept mic-level signals.
1 Stereo input channel XR-20 / XR-24 owner’s manual Controls Module Block diagram PRE FADER ONO LEVEL FREQ LEVEL BAL FREQ LEVEL LEVEL HI MID 400 - 8 KHZ HF 12 KHZ MUTE EQ ON LF 80 HZ LOW MID 80 - 2 KHZ CHAN FADER FOUR BAND EQ - LEFT PRE EQ LF 80 HZ LOW MID 80 - 2 KHZ HI MID 400 - 8 KHZ FOUR BAND EQ - RIGHT p.
Stereo Input channel 1 Front panel features Stereo EQ The Stereo Input channel has two parallel EQ circuits that are controlled by the same set of knobs. high frequency—HF Boost / Cut 15dB boost and cut. Shelving @ 12 kHz high mid—HM Frequency Continuously sweepable between 400 Hz and 8 kHz. Boost / Cut 15dB boost and cut. Bell curve with a Q of 1 Low mid—LM Frequency Continuously sweepable between 100 Hz and 2 kHz. Boost / Cut 15dB boost and cut.
2 Stereo input channel XR-20 / XR-24 owner’s manual Controls Module Block diagram PFL SOLO LEFT PRE FADER SOLO RIGHT TO PEAK CIRCUIT MUTE SOLO DC MONO L-R G1-2 G3-4 FADER AMPS CHAN FADER LEFT +10 BUS ASSIGN SWITCHES POST FADER +10 RIGHT 100MM A1-2 PRE PAN 1-2 LEVEL 1-2 LEFT A1 RIGHT A2 YES PRE SOURCE MUTE ? A3-4 PRE LEV 3 L&R MIXED NO LEFT PRE-SOURCE BUFFERS A5-6 PRE LEV 4 A4 LEV 5 L&R MIXED A5 LEV 6 A6 RIGHT AUX SENDS 1 THRU 6 p.
Stereo Input channel 2 AUX send features Six auxiliary sends are available for creating individual output mixes. These can be used to drive effects processors, provide monitor mixes, create broadcast or alternate sound reinforcement mixes, or for other special requirements. Note: The default PRE setting for the Auxes is pre-fader, but post-mute, post-insert, and post eq.
2 Stereo input channel XR-20 / XR-24 owner’s manual Controls Module PFL SOLO LEFT PRE FADER SOLO RIGHT TO PEAK CIRCUIT MUTE SOLO DC MONO L-R G1-2 G3-4 FADER AMPS CHAN FADER LEFT +10 BUS ASSIGN SWITCHES POST FADER +10 RIGHT 100MM A1-2 PRE PAN 1-2 LEVEL 1-2 LEFT A1 RIGHT A2 YES PRE SOURCE MUTE ? A3-4 PRE LEV 3 L&R MIXED NO LEFT PRE-SOURCE BUFFERS A5-6 PRE LEV 4 A4 LEV 5 L&R MIXED A5 LEV 6 A6 RIGHT AUX SENDS 1 THRU 6 p.
Stereo Input channel 2 Bus assignment features The bus assignment section offers considerable flexibility for creating what eventually becomes the main output mix. Two stereo subgroups are available for creating submixes or separate stereo mixes. When the channel is being used as a stereo input, Left/Right, Groups 1 & 2 Groups 3/4 bus assignments are configured as true stereo pairs. Bus assignments are derived post-fader, post-eq, and postmute.
2 Stereo input channel XR-20 / XR-24 owner’s manual Connectors Rear panel Block diagram BAL MIC IN LINE GAIN 15 - 60 dB MONO LEVEL FREQ LEVEL BAL LF 80 HZ LEFT LOW MID 80 - 2 KHZ FOUR BAND BAL LINE IN 27dB PAD PRE EQ LF 80 HZ LOW MID 80 - 2 KHZ BAL MIC IN FOUR BAND RIGHT SOLO TRIGGER INPUT SIGNAL LED BAL LINE IN INPUT PREAMP 27dB PAD PRE-AMP OUT L&R PEAK R (PFL) SIG G REAR PANEL POST FADER X-RACK STEREO INPUT MODULE 4 OR 8 STEREO INPUTS AVAILABLE +48V ON PFL SOLO LEFT +48V PRE
Stereo Input channel 2 Rear panel features 48 V Phantom power 48 volts DC is applied to pins 2 and 3 on the mic-input XLR connectors. This option is used with condenser microphones and active direct boxes that require an external DC voltage (phantom power ) in order to operate. Line INPUT jacks - Left and Right Line-level signals, balanced or unbalanced, may be brought into the input channel through this jack. The LINE INPUT switch must be pressed for these jack to be active.
3 Master section XR-20 / XR-24 owner’s manual Module Controls Block diagram +9 6 3 0 -3 6 9 12 15 18 21 24 LED METERS FOLLOW SOLO, NORMALLY SHOW L / R OUT LEFT OUT RIGHT OUT SOLO FEED L-R ADD MONO SOLO CTRL RIGHT PRE-FADER SOLO ON L-R MONO GC L R GC AUX1-2 TAPE IN MONITOR LEVEL SOLO OFF SUM MONO TO PHO NES MO N-L MO N-R GC L MONITOR SOURCE SELECT ( SELECTED SOURCES ADD TOGETHER ) MONITOR OUT R GC SOLO FEED L-R SOLO CTRL TAPE-IN LEVEL TAPE TO AUX 1-2 SOLO MIX AMPS SOLO LEFT S
Master section 3 Front panel features The XR-20 & XR-24 have a comprehensive output section, including meters, master level controls, and a flexable group assignment section. Headphone control section In normal use, the headphone out is used to monitor the Solo system. The Solo system is made up of anything that is PFL’d (pre-fader-listen) or AFL’s (after fader listen).
3 Master section XR-20 / XR-24 owner’s manual Controls Module Block diagram +9 6 3 0 -3 6 9 12 15 18 21 24 LED METERS FOLLOW SOLO, NORMALLY SHOW L / R OUT LEFT OUT RIGHT OUT SOLO FEED L-R ADD MONO SOLO CTRL RIGHT PRE-FADER SOLO ON L-R MONO GC L R GC AUX1-2 TAPE IN MONITOR LEVEL SOLO OFF SUM MONO TO PHO NES MO N-L MO N-R GC L MONITOR SOURCE SELECT ( SELECTED SOURCES ADD TOGETHER ) MONITOR OUT R GC SOLO FEED L-R SOLO CTRL TAPE-IN LEVEL TAPE TO AUX 1-2 SOLO MIX AMPS SOLO LEFT SO
Master section 3 Front panel features FROM MONITOR The post-level control MONITOR output becomes the signal in the headphones when nothing is soloed. This overrides TAPE IN if the TAPE IN button is depressed. TAPE IN The TAPE IN signals appear in the headphones when the FROM MONITOR button is not depressed and nothing is Soloed.
3 Master section XR-20 / XR-24 owner’s manual Controls Module Block diagram TAPE-IN LEVEL TAPE TO AUX 1-2 AU LEFT BUS TAPE-IN L AU RIGHT BUS TAPE IN L TAPE TO L/R TAPE-IN R TO: PHONES & MONITOR ADD MONO (RECESSED) TAPE IN R LEFT OUT TAPE-IN L X-RACK AUX BUSES 1-2 (STEREO PAIR) AUX 1 AUX MIX AMPS INSERT SEND / RTN AUX 2 AUX 1-2 MASTER AFL SOLO LEFT +10 AUX 1 OUT AUX 2 OUT GC SOLO RIGHT GC +10 SOLO DC AUX MIX AMP X-RACK AUX BUSES 3 THRU 6 (1 OF 4 SHOWN) INSERT SEND / RTN AUX MASTER
Master section 3 Front panel features TAPE IN level On the rear panel there are Left and Right TAPE IN connectors, both 1/4” TRS and RCA. They can be used to bring in a stereo source such as a two-track playback from tape, CD, MD, or a sampler. This knob controls the level to the Aux 1/2 and Left/Right buses. TAPE IN assignment TO A1-2 This assigns the stereo TAPE IN to Auxes 1 and 2, which are configured as a stereo pair. This is useful for stereo program monitoring.
3 Master section XR-20 / XR-24 owner’s manual Controls Module Block diagram X-RACK GROUPS (1 OF 4 SHOWN) GROUP MIX AMP INSERT SEND / RTN PRE FADER MONO LEFT RIGHT GROUP-TO-MAIN ASSIGN SWITCHES ODD GROUPS FEED LEFT SOLO, EVENS FEED RIGHT SOLO GROUP FADER POST FADER PEAK R (AFL) AFL SIG SOLO DC p.
Master section 3 Front panel features GROUP assignment section The XR-20 offers a flexible group assignment arrangement. Each of the four Groups can be assigned to Left, Right and Mono busses, in any combination. M - Mono assignments for Groups 1, 2, 3 & 4 Each of the four groups has a Mono assignment button for routing its post-fader signal to the Mono mix bus.
3 Master section XR-20 / XR-24 owner’s manual Controls Module Block diagram AUDIO SOURCES FOR MONITOR - ALL PRE-FADER GRP3-4 GRP1-2 L-R MONO AUX1-2 TAPE IN MONITOR SOURCE SELECT ( SELECTED SOURCES ADD TOGETHER ) SOLO FEED L-R SOLO CTRL p.
Master section 3 Front panel features MONITOR Output section The XR-20 and XR-24 offer an extensive monitoring system which can be used for several alternate mix and remote listening purposes. The main L/R & M mixes, the Groups, Auxes 1&2, the Tape IN, and the Solo system can all be routed to the Monitor outs. Like the Headphone section, the SOLO system is automatically routed to the Monitors. This can be defeated by pressing the SOLO OFF button.
3 Master section XR-20 / XR-24 owner’s manual Controls Module Block diagram AUDIO SOURCES FOR MONITOR - ALL PRE-FADER GRP3-4 GRP1-2 L-R MONO AUX1-2 TAPE IN MONITOR SOURCE SELECT ( SELECTED SOURCES ADD TOGETHER ) SOLO FEED L-R SOLO CTRL p.
Master section 3 Front panel features MONITOR Output section SOURCE SELECT The Source select portion of the Monitor system allows you do assign the primary mix buses to the Monitor outputs. All assignments are post insert, pre-fader. All selected sources are added (summed) together. TAPE IN Assigns the TAPE IN L & R signals to the monitors. The TAPE IN jacks are located on the rear panel. 1/4” TRS jacks and RCA phone plugs are provided for easy hookup.
3 Master section XR-20 / XR-24 owner’s manual Controls Module Block diagram X-RACK MAIN OUT LEFT-RIGHT LEFT MIX AMP L-PRE FADER L/ R SIGNAL LED PEAK SIG RIGHT MIX AMP L-INSERT SEND / RTN LEFT FADER MIC LEVEL L-POST FADER +10 R LEFT BAL OUT 30dB PAD 100MM G R-INSERT SEND / RTN RIGHT BUS IN R-PRE FADER MIC LEVEL RIGHT FADER R-POST FADER LEFT BUS IN +10 RIGHT BAL OUT 30dB PAD 100MM X-RACK MAIN OUT MONO MONO MIX AMP MONO SIGNAL LED MONO BUS IN M-PRE FADER SIG SOLO DC p.
Master section 3 Front panel features Mono PK/SIG LED Green/Red - Flashes to indicate the Mono master level. Green during normal operation and red to indicate overload either at the mix amp or at the fader. Left/Right PK/SIG LED Green/Red - Flashes to indicate the summed Left/Right master levels. Green during normal operation and red to indicate overload either at the mix amps or at the faders. MONO AFL Assigns the post-fader Mono master signal to Solo bus, and illuminates the Peak (red) LED.
3 Master section XR-20 / XR-24 owner’s manual Connectors Rear panel Block diagram X-RACK MAIN OUT LEFT-RIGHT LEFT MIX AMP L-PRE FADER L/R SIGNAL LED PEAK SIG RIGHT MIX AMP L-INSERT SEND / RTN LEFT FADER MIC LEVEL L-POST FADER +10 R LEFT BAL OUT 30dB PAD 100MM G R-INSERT SEND / RTN RIGHT BUS IN R-PRE FADER MIC LEVEL RIGHT FADER R-POST FADER +10 LEFT BUS IN RIGHT BAL OUT 30dB PAD 100MM X-RACK MAIN OUT MONO MONO MIX AMP MONO SIGNAL LED MONO BUS IN M-PRE FADER MONO FADER PEAK R (AFL
Master section 3 Rear panel features Left, Right and Mono bus inputs These three female XLR’s are used to bring external signals directly into the Left, Right and Mono mix buses. This is useful for linking multiple mixers together. Group 1, 2, 3 & 4 bus inputs These 1/4” TRS jacks are used to bring external signals directly into the first four sub groups. This is useful for linking multiple mixers together. p.
3 Master section XR-20 / XR-24 owner’s manual Rear panel Block diagram X-RACK GROUPS (1 OF 4 SHOWN) GROUP MIX AMP INSERT SEND / RTN PRE FADER MONO LEFT RIGHT GROUP FADER POST FADER GROUP-TO-MAIN ASSIGN SWITCHES ODD GROUPS FEED LEFT SOLO, EVENS FEED RIGHT SOLO GROUP BUS IN TO GROUP MIX-AMP +10 GROUP LED GROUP OUT 60MM PEAK R (AFL) GC AFL SOLO LEFT SIG G SOLO RIGHT SOLO DC X-RACK AUX BUSES 1-2 (STEREO PAIR) AUX 1 AUX MIX AMPS INSERT SEND / RTN AUX 2 AUX 1-2 MASTER A FL SOLO LEFT +10
Master section 3 Rear panel features AUX Inserts 1 through 6 The Aux masters have pre-fader inserts for patching in signal processors. This is useful when using Aux outputs for stage monitors. Tip is Send and Ring is Return. Aux OUT TRS Jacks 1 through 6 The six post-fader Aux master outputs are available at these 1/4” TRS jacks. Aux OUT XLR’s 1 through 6 The six post-fader Aux master outputs are also available at these male XLR jacks.
3 Master section XR-20 / XR-24 owner’s manual Use 5-Pin DIN cable to interconnect two Consoles SOLO LINK IN OUT SOLO-LINK: TIES SOLO AUDIO AND CONTROL BETWEEN CONSOLES. SLAVE SOLOS SHOW UP ON MASTER CONSOLE. SOLO-LINK CONNECTORS.
Master section 3 Rear panel features Solo Link When using multiple X-Rack mixers together, the solo systems can be linked. A 5-pin DIN cable is used to link the Solo Audio and control signals. AC Input The XR-20 and XR-24 use an internal switching power supply which is capable of accepting a wide range of line voltages. This industry-standard IEC connector will mate up with any of the common IEC line cords. The in-coming voltage can be anywhere between 100 and 240 volts, +/- 10%.
p.
Specifications 4 Specifications Frequency response THD Noise Crosstalk Phase Shift +0/-1dB 20Hz-20kHz ref 1kHz (any input to any output) any output <0.
XR-20 / XR-24 owner’s manual Version 1.0 March 28, 20001 Crest P/N D7000025 Crest Audio 100 Eisenhower Drive Paramus NJ 07652 (201) 909-8700 www.crestaudio.
