Summary of SP2
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Seeburg acoustic line active systempanel 2 owner´s manual.
Page 2: Table Of Contents
Table of contents 1 introduction 1 1.1 how to use this manual 2 2 the controls and connectors 2 3 operating the sp2 4 3.1 active frequency dividing network 4 3.1.1 3 db point 4 3.1.2 filter falloff 4 3.1.3 phase correction 4 3.1.4 highmid attenuator 5 3.1.5 mono-bass option 6 3.2 limiter operation 6...
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Seeburg acoustic line sp2 owner’s manual page 1 1 introduction your new acoustic line sp2 is a very flexible device. Due to its wide range of adjustable parameters it can also conveniently be used as an add-on for existing pa systems. Read this owner’s manual carefully before putting your sp2 into o...
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Caution: before opening the device must be turned off and the power line must be disconnected! The manufacturer will accept no responsibility whatsoever for any damage caused by improper handling of this device. 1.1 how to use this manual this owners manual is written to assist you in setting the sp...
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Seeburg acoustic line sp2 owner’s manual page 3 fig. 3 front panel facilities fig. 4 rear panel facilities.
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All sp2 inputs and outputs are electronically balanced. A balancing transformer can be installed as an option if dc isolation is a requirement. If you wish to have this modification installed in your sp2 please contact your authorized seeburg acoustic line dealer. 3 operating the sp2 3.1 active freq...
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Fig. 6 displaced speakers the phase correction angle ( Φ in degrees) for a known speaker displacement is given by Φ ∆ = ⋅ °⋅ s f c 360 ∆ s: speaker offset in m c: speed of sound in air. (given an air pressure of 101.3 hpa and a temperature of 20° celsius c is 340 m/s. The temperature coeff icient is...
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Fig. 7 highmid attenuation jumper socket. 3.1.5 mono-bass option if you intend to use a system with a single bass speaker cabinet, use the sp2’s mono-bass function. To this end you have to latch the two blue wire breakers which are labeled ‘mono-bass’. The effect is an identical bass signal at the w...
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Fig. 8 characteristic curve of the sp2 limiter. The limit indicator led lights up at point a. The compression ratio increases with an increasing input signal (area between a and b). The maximum compression ratio of 1:20 is reached beyond b. 3.3 subsonic and ultrasonic filters the subsonic filter is ...
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Fig. 9 measured frequency response curves for eq1 fig. 10 measured frequency response curves for eq2 fig. 11 measured frequency response curves for eq3.
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Fig. 12 measured frequency response curves for eq4 as can be seen in fig. 9 through fig. 12, there is a falloff of the zero amplitude curves below 50 hz and above 15 khz. This is due to the subsonic/ultrasonic filters, which are always in operation (see section 3.3). 3.4.2 adjustment of the filter q...
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4 appendix 4.1 tables sip-re sisto r- fre q ue ncy a rra y x-ove r eq1 eq2 eq3 eq4 470 2400 330 1250 7000 19000 560 2100 305 1100 6400 17500 680 1600 280 1000 6000 16000 820 1400 290 920 5700 15500 1k 1200 240 880 5000 13500 1,2k 1000 205 800 4250 11500 1,5k 800 185 700 3800 10500 1,8k 750 162 610 3...
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Co nfig ura tio n t hre s ho ld s 1 s 2 s 3 s 4 s 5 u p 16 p 8 p 4 p 2 off off off off off 12 9 18 36 72 o n off off off off 15 14 28 56 113 off o n off off off 18 20 41 81 162 o n o n off off off 21 28 55 110 221 off off o n off off 24 36 72 144 288 o n off o n off off 28 49 98 196 392 off o n o n ...
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4.2 note - chart for sp2 configurations fig. 14 simplified sp2 layout can be used as a note chart for controller configurations..
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4.3 factory presets sp2 units which have not been delivered as part of a seeburg acoustic line sytem are factory preset as follows: x-over: 3 db point (sip): 105 hz (12 k Ω ) filter falloff: 24 db/oct. Phase angle highmid and woofer: 0 ° attenuation highmid: 0 db mono-option: off eq 1: center freque...
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4.4 sp2 specifications snr (at 6 db gain): > 103 db (eq included) thd (at 6 db gain): headroom: 22 dbu subsonic/ultrasonic filters: -3 db points at 25 hz and18 khz -18 db/octave output impedance (signal to amp): 600 Ω input impedance (audio in): 40 k Ω ac mains / power draw: 230 volt/ac/10 va (eq in...
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4.6 glossary • compression ratio: compressors limit the audio signal amplitude whenever it surpasses a certain preset threshold level. The characteristic curve’s slope equals 1 below this threshold, meaning that the output amplitude is the same as the input amplitude. At the threshold point the curv...
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Fig. 16 two waves of equal amplitude, frequency and phase add up to a wave of twice the amplitude (a). • filter q: the quality factor (q) of a resonant filter is a measure for the sharpness of the resonance peak that can be realized with this circuit. Every equalizer contains a number of electric re...
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Seeburg acoustic line gmbh auweg 32 d-89250 senden/freudenegg www.Acoustic-line.De.