User manual GENELEC 7073APM

7073A Operating Manual Genelec 7073A Active Subwoofer 7073A Active Subwoofer General description Genelec 7073A is a powerful active subwoofer incorporating all the amplifier and crossover electronics needed for bass management and reproduction of low frequency information in modern 6.1 or 5.1 channel surround sound or traditional stereo systems. Its 19 to 120 Hz (±3 dB) frequency range and 124 dB sound pressure output capability are sufficient to handle the most demanding and powerful applications. The low pass section sensitivity can be adjusted from +6 dBu to -12 dBu to allow easy subwoofer level matching with various main speakers. All outputs have 0 dB passband gain. The low pass frequency of the LFE input channel can be set to 85 Hz, 120 Hz or 85 Hz with "Redirect" function that routes LFE content above 85 Hz to the front center monitor. The input sensitivity of the LFE channel can be set to 0 dB or +10 dB. Balanced XLR connectors are used for the system audio inputs and outputs. Two "Bass Roll-Off" switches are included to provide a flat bass response in all acoustical environments, enabling adjustments of the subwoofer response in three -2 dB steps. Two phase matching switches in the crossover allow compensation for the delay which occurs if the subwoofer is placed away from the main speakers, or for other speaker systems phase behaviour. Four settings are provided between 0° and 270°. An 85 Hz test tone generator is included to help achieve accurate crossover phase alignment. Top row LFE IN / SUM IN: Use this connector for the LFE or .1 output channel of a 5.1- or 6.1-channel discrete surround sound source, or the SUM OUT signal from the Installation Each subwoofer is supplied with a mains cable and an operating manual. Once unpacked, place the subwoofer in a suitable location (for more details see the "Positioning" section). Before connecting the audio signals, ensure that both the subwoofer and the main monitors are switched off. Check that the voltage selector switch is set according to your local mains voltage. Audio connections to the subwoofer are made via balanced XLR connectors. An unbalanced source can also be used with a special RCA to XLR cable; the correct connection for the cable is shown in Fig. 2. However, we recommend the use of balanced cables and connectors due to their better noise immunity. The connectors are arranged in three rows on the connector panel (see Fig. 1): Bass management unit The proprietary built-in bass management unit has six signal input and output channels (L/C/R Front and L/C/R Rear), a discrete LFE signal input and a summed signal output, providing great flexibility and easy connection in all monitoring environments. The active crossover contained in the bass management unit splits the input signals into low and high frequency components at 85 Hz. Frequencies below 85 Hz are directed to the subwoofer and frequencies above 85 Hz to the main speakers. Figure 2. XLR to RCA connector for unbalanced operation. Figure 1. 7073A's connector panel, connectors and controls. "master" subwoofer in a daisy-chained multiple subwoofer configuration. Note that the "subwoofer out" channel of an analogue matrix surround decoder (Dolby Surround, Dolby Pro Logic) should not be connected to the "LFE IN" input. See section "Subwoofer in analogue matrix sound systems". SUM OUT: Use this output connector when you want to link another subwoofer to your system. "SUM OUT" carries an unfiltered sum of signals combined from all input channels. See section "Using multiple subwoofers". Middle row FRONT L, C, R CHANNELS IN/OUT: Use these connectors for the Front Left, Center and Right channels of a surround sound system or the Left and Right channels of a Stereo system. Connect line level signal cables from your signal source to their respective "LEFT IN", "CENTER IN" and "RIGHT IN" connectors. Then connect the subwoofer to your main monitors with XLR cables from the "LEFT OUT", "CENTER OUT" and "RIGHT OUT" connectors. All "L, C and R OUT" channels are high pass filtered with the filtering frquency fixed at 85 Hz (12 dB/octave). The placement will affect the phase difference between the main monitors and the subwoofer, and also the bass roll-off rate. These effects can be compensated by the use of the controls in the amplifier unit; but we recommend that at first you leave the switches untouched and concentrate on finding the position where the subwoofer gives the smoothest response, and only then use the controls to fine-tune the balance and phase alignment between the subwoofer and the main monitors. To begin with, place the subwoofer slightly offset from the center of the front wall. The recommended distance to the wall is less than 60 cm / 24" measured from the subwoofer's drivers. This position gives increased acoustic loading (and SPL) due to the proximity of the front wall and floor and avoids low frequency cancellation and comb filtering. Front wall cancellation for the 85 Hz high pass filtered main speakers can be eliminated by placing them at least 110 cm / 43" away from the front wall. In a multichannel system the main monitors should ideally be positioned symmetrically and at an equal distance Bottom row REAR L, C, R CHANNELS IN/OUT: Use these connectors for the Rear Left, Center and Right channels of a surround sound system. The connection is made in the same way as with the Front channels. The rear channels are also high pass filtered at 85 Hz. Once all connections have been made, the subwoofer and main monitors are ready to be powered up. Positioning in the room The placement of the subwoofer in the room affects the overall frequency response and sound level of the system dramatically, as at low frequencies the effects of the room are strong. Even a slight change in the subwoofer's location can make a marked difference in the frequency balance and often patient and methodical experimentation and testing is needed to find the optimum placement. Subwoofer placement Near to a wall 20 cm (8") Bass Roll-Off setting -2 dB -6 dB -2 dB In a corner Flush mounted GENELEC GENELEC GENELEC GENELEC Table 1. Suggested Bass Roll-Off settings Figure 3. Flush mounting the subwoofer. Note the clearance needed on the reflex port side. HEAVY WOODEN OR CONCRETE WALL ABSORBING MATERIAL HEAVY WOODEN OR CONCRETE WALL HEAVY WOODEN OR CONCRETE WALL ABSORBING MATERIAL VIBRATION ISOLATORS f ~ 2-8 Hz VIBRATION ISOLATORS f ~ 2-8 Hz VIBRATION ISOLATORS f ~ 2-8 Hz Figure 4. Flush mounting the subwoofer in a non-absorbing wall. Figure 5. Correct flush mounting in a semiabsorbing wall. Figure 6.Incorrect flush mounting in a semiabsorbing wall. from the listening position (see ITU-R BS.775-1 recommendation for speaker placement for multichannel audio). If the frequency balance is not right, try moving the subwoofer slightly to the left or right so that different room modes are excited at different levels. Positioning the subwoofer close to a corner will boost the bass level at lower frequencies and may cause asymmetrical spatial imaging. If you are using two subwoofers, try placing them asymmetrically relative to the side walls. Sometimes moving the subwoofers apart into the front corners helps with problematic rear wall reflections and the loss of mutual coupling is compensated by the bass boost caused by corner positioning. Although the 7073A subwoofer is magnetically shielded, it may cause some picture distortion if placed near very sensitive video monitors or computer displays. grilles or place the subwoofer so that there is less than 10 centimeters (4") of free space in front of the grilles. The reflex port and connector panel should always have a clearance of at least 20 centimeters (8") to any objects to ensure proper function of the port and cooling for the electronics attached to the connector panel. absorbing front wall structure and the depth of the absorbing material exceeds the depth of the 7073A cabinet, there is a risk of low frequency comb filtering due to the reflections from the wall behind the subwoofer (See Fig. 6.). Setting the input sensitivity The subwoofer requires input sensitivity alignment to the source to obtain a correctly balanced system. The input sensitivity control is located on the connector panel of the subwoofer. An input voltage of -6 dBu with a -6 dBu input sensitivity setting will produce 100 dB SPL @ 1m in free field. To obtain a 110 dB SPL output an input voltage of +10 dBu is required when the input sensitivity is set to 0 dBu. Flush mounting the subwoofer If the 7073A subwoofer is flush mounted into a wall or a cabinet, it is important to ensure unrestricted airflow from the reflex port and cooling for the electronic components. This can be done by making the recess 20 centimeters (8") wider than the subwoofer. Place the subwoofer into the right end of the recess with the drivers' side facing the room. This leaves 20 centimeters (8") of free space on the connector panel and reflex port side. The height and depth of the recess should not be any bigger than those needed to fit the subwoofer flush with the wall surface (See Fig 4-5). If the 7073A is flush-mounted in a semi- Setting the Bass Roll-Off switches The acoustic response of the subwoofer may have to be matched to the characteristics of the room and the positioning in which it will be used. To adjust the subwoofer to match these characteristics use the ''Bass Roll-Off' control switches located on the connector panel. Table 1 Minimum clearances to walls or other objects The power amplifiers are attached to the lower part of the aluminium grilles, which function as a heatsink. Do not cover the Finally, set the -180° phase switch (DIP 4) to the opposite setting and deactivate the test signal. Phase Difference: 0° Phase Difference: 90° Phase correction method with test equipment The following procedure matches the phase between the subwoofer and the main monitors using a frequency analyser and a pink noise generator. Connect a high grade measuring microphone to the analyser and feed pink noise into the "CENTER IN" input of the subwoofer. The subwoofer's bass management system will direct the frequencies above 85 Hz to the 85 Hz 85 Hz Phase Difference: 180° Phase Difference: 270° 85 Hz 85 Hz center main monitor while the subwoofer reproduces the frequencies below 85 Hz. Position the microphone at the listening Figure 7. The effect of phase difference between the subwoofer and the main monitors position and adjust the input sensitivity of the subwoofer until frequencies below and above 85 Hz are reproduced at equal level. provides some suggestions for the "Bass Roll-Off" switch settings. When both rolloff switches are set to "OFF", a flat anechoic response is obtained. generator to accomodate easy phase alignment. The test tone generator is connected to the subwoofer's "FRONT CENTER OUT" channel only. In a stereo system it is necessary to temporarily connect either of the channels to this output. Power up the system and set the DIP switches 3 (SUM IN MODE) and 4 (LFE +10 dB) on the first switch group to "ON" Now you should hear an 85 Hz test signal from the subwoofer and the main monitor connected to the center channel output. Toggle the -180° phase switch (DIP 4 on the second switch group) on and off, and set it to the position which gives the lowest sound level at the listening position. Next toggle the -90° phase switch (DIP 3) on and off, and again set it to the position which gives the lowest sound level at the listening position. Then adjust the phase control switches for the maximum dip of at least -6 dB at the crossover frequency (85 Hz). Change the -180° switch to the opposite setting. The phase should now be set correctly and the frequency analyser should show a smooth response around 85 Hz. Setting the phase control Incorrect phase alignment between main monitors and subwoofer causes a drop in the frequency response of the whole system at the crossover frequency. The graphs above (Fig. 7) show the effect of phase difference to the frequency response. The phase difference between the main monitors and subwoofer at the listening position is dependent upon the position of the subwoofer, so the phase adjustment should be done only after the preferred position is found. Acoustic measuring equipment is required for accurate system alignment. If this equipment is not available, the following coarse phase matching can be applied. Overload indicators The mode indicator LED on the connector panel will turn from green to yellow to indicate clipping and then to red to indicate that the protection circuit has activated. If this occurs frequently, reduce the input level to the subwoofer until the LED remains green. If the LED on the connector panel is not easily visible, the optional Remote LED Kit can be used to bring it into view. The kit consists of a LED in a compact case and an RJ11 cable to connect the case and the "REMOTE" RJ11 connector on the connector panel. Coarse phase adjustment method Genelec 7073A subwoofer is equipped with a built-in 85 Hz frequency test tone Subwoofer bypass control A bypass control feature is included in the subwoofer circuits so that the effect of the subwoofer on the whole moni- tor system can be determined. With the bypass switch on, the high pass filters for the main monitors are overridden and the system behaves as if the subwoofer was not connected. The bypass function has no effect on the LFE input. Two different bypass remote controllers are available as optional equipment: 1092-400 switch that can be connected to a 1/4" jack connector on the connector panel and 7000-416 that connects to the "REMOTE" RJ11 connector. The 7000-416 option also includes remote control of the "LFE +10 dB" function and a link for the 7000-415 remote LED option. or 19 to 120 Hz by using the "LFE BANDWIDTH" switch. If the LFE signal includes higher frequencies than 120 Hz, they can be monitored by using the "Redirect" function: Set "LFE BANDWIDTH" switch to "85" and the "REDIRECT" switch to "ON". Now the subwoofer reproduces LFE frequencies up to 85 Hz and reroutes all higher LFE content to the front center channel. This is the most flexible setting for LFE signal management, as it ensures that all LFE content can be monitored in all situations and encoding formats. Note that the "Redirect" function is not enabled when the "LFE BANDWIDTH" switch is set to 120 Hz. Typical applications of different LFE bandwidth settings As stated above, using the 85 Hz LFE bandwidth setting with "Redirect" function is the most universal configuration for LFE monitoring. However, there are situations when the band-limited LFE settings serve a definite purpose. Limiting the LFE bandwidth to 85 Hz without using the "Redirect" function can be used to simulate the effect of some consumer decoders that do not replay information above 80 Hz on the LFE channel when the bass management is used. Checking the multichannel mix with this setting on lets you know how it translates in systems with this limitation. The 120 Hz LFE bandwidth setting complies with the replay systems of movie theaters and cinemas. 35 mm movie soundtracks use the LFE channel to reproduce a bandwidth of 20 - 120 Hz through dedicated subwoofers. In this case the LFE and main channel bandwidths overlap between 85 and 120 Hz, which may create unwanted acoustical summing if the same signal is present in both channels. To avoid this, the LFE content should be kept completely different (de-correlated) from the low frequency content of the main channels when mixing music and sound effects for film release. Using the LFE +10 dB function In Dolby Digital and DTS encoding formats the LFE channel has to be monitored with +10 dB gain in relation to the main channels. The object is to increase the recording headroom of the LFE channel. Consumer and theatrical decoders automatically add +10 dB of LFE gain to restore the level balance. The "LFE +10 dB" function on the 7073A subwoofer is designed to add the +10 dB gain to the LFE channel in the production stage, if it is not already done in the output matrix of the mixing console. The function is activated by switching the "LFE +10 dB" dip switch on the subwoofer's first switch group to "ON" or by using the remote control. A yellow LED indicates that the function has been activated. The "LFE +10 dB" function should not be used in following cases: Subwoofer in analogue matrix surround sound systems. When using the 7073A subwoofer in a consumer analogue matrix surround sound system, such as Dolby Surround, Dolby Pro-Logic or Pro-Logic II or a professional matrix decoder such as a Dolby SDU-4, route the front channels through the subwoofer so that the output of the subwoofer is matched to the rest of the system and select "Large" setting for the front speakers on the decoder. If there is a subwoofer channel output on the decoder it should NOT be connected to the subwoofer's "LFE IN" input since the processing within an analogue decoder will conflict with the filtering in the subwoofer. Connecting the rear channels to the subwoofer is optional since the rear channels from most matrix decoders are band limited down to 100 Hz. · If the +10 dB LFE gain is already · When producing an audio format that does not require the use of +10 dB gain on the LFE channel, such as DVD-Audio (MLP), SACD (DSD) etc. Digital or DTS soundtrack. The decoder will automatically provide +10 dB LFE gain. implemented by another device. · When monitoring a decoded Dolby Using multiple subwoofers The Genelec 7073A subwoofer is equipped with a "SUM OUT" connector to provide an easy way of coupling two or more subwoofers together in high SPL applications. Connect an XLR cable from the "SUM OUT" connector of the "master" subwoofer to which the main monitor channels are connected, to the "LFE IN / SUM IN" connector of the other, "slave" subwoofer and turn the "SUM IN MODE" dip switch on the "slave" subwoofer to "ON". When two subwoofers connected in this way are positioned close to one another, bass level increases by 6 dB. Three subwoofers give an SPL increase of 9,5 Monitoring the LFE channel in digital discrete surround sound systems Some digital surround sound systems use a discrete Low Frequency Effects channel which should be connected to the "LFE IN" input on the connector panel. This enables the subwoofer to correctly reproduce all the bass information in the mix. The LFE channel on the 7073A can be set to two frequency ranges: 19 to 85 Hz dB and four subwoofers 12 dB compared to a single subwoofer. Adjust the sensitivity control of all subwoofers in the group to match the SPL level of the main monitor system. Phase and Bass Roll-Off adjustments should be done individually for each subwoofer in the chain, especially if they are not placed close together. To check the phase alignment for the "master" subwoofer switch off the "slave" subwoofer and follow the instructions given in the previous sections. To adjust the phase alignment of the "slave" subwoofer, you need to switch off the "master" subwoofer, connect a signal cable from the "slave" subwoofer's "FRONT CENTER OUT" connector to the center channel monitor and switch the "SUM IN MODE" switch to "OFF". This effectively changes the "slave" to "master" mode and the phase adjustment can be carried out. Return the connections and "SUM IN MODE" setting on the "slave" subwoofer back to the "SUM IN" mode after completing the adjustment. Warning! This equipment is capable of delivering sound pressure levels in excess of 85 dB, which may cause permanent hearing damage. Figure 8. The free field frequency response of the 7073A subwoofer at different Bass Roll-Off settings Figure 9. The curves above show the harmonic distortion analysis of the 7073A in free field. In half space the SPL will be 6 dB higher. Safety considerations Genelec 7073A subwoofer has been designed in accordance with international safety standards. However, to ensure safe operation and maintain the unit in safe operating condition, the following warnings and cautions must be observed: Maintenance No user serviceable parts are inside the amplifier unit. Any maintenance of the unit must only be performed by qualified service personnel. Figure 10. 1092-400 "Bypass" switch Guarantee This product is supplied with a ONE year guarantee against manufacturing faults or defects that might affect the performance of the unit. Refer to supplier for full sales and guarantee terms. Figure 11. 7000-415 Remote Power/OVL LED · Do not expose the subwoofer to water or moisture. Do not place any objects filled with liquid, such as vases on the subwoofer or near it. be performed by qualified service · Servicing and adjustment must only · Opening the connector panel is strictly prohibited except by personnel. Accessories 1092-400 1/4" jack "Bypass" switch 7000-415 RJ11 remote Power/ Overload indicator LED 7000-416 RJ11 remote control for "Bypass" and "+10 dB LFE" functions Figure 12. 7000-416 Remote control switch for "Bypass" and "+10 dB LFE" functions · Always use a mains power personal injury. qualified service personnel. connection with protective earth. Failing to do this may lead to 7073A Operating Manual SYSTEM SPECIFICATIONS 7073A Free field frequency response (+/- 3 dB) Maximum short term sine wave SPL output averaged from 30 to 85 Hz, measured in half space at 1 meter Maximum peak SPL output with random pink noise, measured in half space at 1 meter Self generated noise level in free field @ 1 m on axis (A-weighted) Harmonic distortion at @ 1 m on axis in half space 2nd 3rd Drivers Weight Dimensions Height Width Depth 19 Hz...85 Hz LFE 85/120 Hz Input connector XLR female pin 1 pin 2 pin 3 Input impedance Input level for 100 dB SPL output @ 1 m INPUT SECTION 7073A gnd + ­ 10 kOhm balanced Variable from +6 to ­12 dBu 124 dB SPL 129 dB SPL 20 dB @ 105 dB SPL 30 ... 85 Hz 2% 2% 4 x 305 mm (12") 120 kg (265 lbs) 524 mm (20 5/8") 1440 mm (56 11/16")* 558 mm (22") * If the subwoofer is flush mounted into a wall or a cabinet, the recess must be 20 cm (8") wider than the subwoofer to allow sufficient clearance for the reflex port situated at the end of the subwoofer enclosure. OUTPUT SECTION 7073A Output connector XLR male pin 1 pin 2 pin 3 Remote LED connector (RJ11) Main monitor Out gain Sum/Link Out gain gnd + ­ Remote LED for Power/Overload+Bypass 0 dB 0 dB CROSSOVER SECTION 7073A Subsonic filter (18 dB/octave) below Upper bandwidth/LFE cutoff Crossover frequency, (sub/main channels) Crossover slopes Lowpass Highpass Midband rejection >400 Hz Bass roll-off control operating range in 2 dB steps Phase matching control in 90° steps CONTROLS 7073A Input sensitivity +6 to ­12 dBu 0/-2 dB/ -4 dB/ -6 dB@ 20 Hz 0 / 90 / 180 / 270° 85 / 120 Hz selectable Bypasses the bass management for the main channels 0 / +10 dB Redirects LFE channel signal above 85 Hz to center channel Changes subwoofer to Sum in mode 85 Hz 19 Hz 85 Hz/120 Hz selectable 85 Hz 36 dB/octave 12 dB/octave 50 dB From 0 to ­6 dB @ 20 Hz From 0 to 270° @ 85 Hz Bass roll-off Phase LFE/upper bandwidth limit Bypass LFE sensitivity Redirect Sum in Test tone for phase adjustment AMPLIFIER SECTION 7073A Short term amplifier output power (Long term output power is limited by driver unit protection circuitry) Amplifier system distortion at nominal output THD Mains voltage Power consumption (average) Idle Full output 1000 W 0.05% 100 / 200V or 115 / 230V 60 VA 1000 VA Genelec Document D0049R001. Copyright Genelec Oy 4.2003. All data subject to change without prior notice International enquiries: Genelec, Olvitie 5 FIN-74100, Iisalmi, Finland Phone +358 17 83 881 Fax +358 17 812 267 Email genelec@genelec.com In the U.S. please contact Genelec, Inc., 7 Tech Circle Natick, MA 01760, USA Phone +1 508 652 0900 Fax +1 508 652 0909 Email genelec.usa@genelec.com In China please contact: Genelec China Representative Office Soho New Town, 88 Jianguo Road D-1504, Chaoyang District Beijing 100022, China Phone +86 10 8580 2180 Fax +86 10 8580 2181 www.genelec.com