Infinity Beta SW-12, Preliminary Service Manual, Page: 3 / 38

SW-12 300W Powered Sub/ Plate Amp
LINE VOLTAGE Yes/No Hi/Lo Line Nom. Unit Notes
US 120vac/60Hz Yes 108-132 120 Vrms Normal Operation
EU 230vac/50-60Hz Yes 207-264 230 Vrms Normal operation, MOMS required
Parameter Specification Unit
QA Test
Limits Conditions Notes
Amp Section
Type (Class AB, D, other) D n/a n/a
Bridge type amplifier, None of the speaker
terminals must be connected to system GND at
any time.
Load Impedance (speaker) 6 Ohms n/a Nominal
Rated Output Power 250 Watts
225
1 input driven
Limiter prevents continuous power to exceed
240 Watts, amplifier delivering power in excess
of 300 Watts at 4 Ohms of load impedance.
THD @ Rated Power 0.1 % 1 22K filter
THD @ 1 Watt 0.1 % 0.2 22K filter
Dynamic Power 400 Watts 380
Power is the average measurement
of the first consecutive cycles of the
burst signal
3/20 Cycles @ 50 Hz, burst test into 4 Ohms,
input driven 6dB above its maximum sensitivity,
volume level at Maximum, RABOS Section OFF
DC Offset 10 mV-DC
60
@ Speaker Outputs
Damping factor >50 DF 23 Measured at amplifier board
Measured at the speaker cable. 200 Watts,
measured at speaker output terminals located at
the amp board.
Input Sensitivity
Input Frequency
30 Hz 30 Nominal Freq.
L&R 14.7 mVrms ±2dB To 1 Watt
Single input driven, Ap Zo=600 Ohms, LP ON,
RABOS OFF, Volume ctrl & crossover at max
LP Off Mode selected 14.7 mVrms ±2dB To 1 Watt
Single input driven , Ap Zo=600 Ohms, LP OFF,
RABOS OFF, Volume ctrl & crossover at max
Speaker/Hi Level Input 0.206 Vrms ±2dB To 1 Watt
Single input driven, Ap Zo=25 Ohms, LP ON,
RABOS OFF, Volume ctrl & crossover at max
Signal to Noise
SNR-A-Weighted
100 dBA 90 Relative to rated power A-Weighting filter
SNR-unweighted 90 dBr 85 Relative to rated power 22K filter
SNR rel. 1W-unweighted 60 dBr 55 Relative to 1W Output 22K filter
Residual Noise Floor 0.5 mVrms 1
Volume @max, using RMS reading
DMM/VOM (or A/P)
Residual Noise Floor 0.5 mVrms(max) 1
Volume @max, w/ A/P Swept
Bandpass Measurement (Line
freq.+ harmonics)
Input Impedance
Line Input (L, R,LFE) 10K ohms
n/a
Nominal
Speaker/Hi Level Input 10K ohms
n/a
Nominal
Filters
LP 4th order variable
50-150 Hz ± 10
Subsonic filter (HPF) 2nd Orde Fixed Hz ± 10
Low pass filter OFF Fixed Hz ± 10 L or R input driven, LP Filter OFF
BOS
Frequency Control
--
Range 20-80 Hz functional 21 detent pot (0.1 oct. steps)
Level Control
-- --
Range -14.1 to 0 dB functional 21 detent pot (0.5dB steps)
Width(Q) Control
-- --
Range 4.5% to 49.5% octave functional 21 detent pot (5steps/0.1 octave)
Limiter
THD at Max. Output Power
YES n/a functional
Features
--
Auto - On -Off YES -- functional
No switch to select the ATO mode is provided,
Refer to ATO section
Phase switch 0-180 deg
functional
Volume pot Taper (lin/log) LOG -- functional A Taper
Variable crossover 50-150 Hz YES functional 4th Order LP Variable crossover
HP Speaker out YES functional Pass through from the speaker input section
LP On- Off Select switch YES -- functional Disables LP filter, intended for LFE
Input Configuration
SW-12
2