SAE Mark XXVIIB equalizer

 

Stereo Half Octave Equalizer

The SEA Mark XXVIIB is a highly sophisticated frequency modification system that compensates for room acoustic, balances speaker response, selectively filters noise, equalizes sound for recording, induces stereo on mono program sources and aids in solving most reproduction problems.

Twenty low-noise, low-distortion band pass filters per channel  are provided where each filters center frequency is separated by one-half octave. The filter range effectiveness is selectable at either ±8 dB max or ±16 dB max. Grain or attenuation on the individual filters are independently controlled by calibrated professional slide potentiometers.

Further flexibility is offered in normalizing room acoustics with the inclusion of a "pink Noise" generator. This generator offers the flexibility of calibrating your system for minimum frequency distortion, as well as checking for proper speaker phasing and energy balance. Utilizing our professionally proven precision wound toroid inductors in the classic L-C-R configuration, the mark XXVIIB provides uncompromising performance with low noise (greater than -100 dB) and low harmonic and Intermodulation Distortion Distortion (0,02 T.H.D. and 0,02 Intermodulation Distortion). The full complementary output circuit offers adequate drive for any equipment the Mark XXVIIB will interface with in home or professional applications.

 

Specifications

Frequency Response:  20 Hz - 20,000 Hz ±0,25 dB

Bandwidth:  3 dB down at 6 Hz and 80 kHz

Total Harmonic Distortion (at any level to rated output from 20 Hz to 20 kHz):  less than 0,02%

Intermodulation Distortion:  less than 0,02%

Signal-to-Noise Ratio :  greater than 100 dB below rated output

Rated Output:  2,5 Volts RMS

Output at Clipping:  greater than 12 Volts into 100 k Ω ; greater than 8 Volts into 600 Ω

Input Impedance:  100 k Ω

Output Source Impedance:  150 Ω

Output Load Impedance:  600 Ω  minimum

Insertion Loss:  less than 1 dB with controls centered

Equalizer Range:  ±16 dB or ±8 dB at 20 Hz, 40 Hz, 60 Hz, 80 Hz, 120 Hz, 160 Hz, 240 Hz, 320 Hz, 480 Hz, 640 Hz, 960 Hz, 1280 Hz, 1800 Hz, 2500 Hz, 3700 Hz, 5000 Hz, 7500 Hz, 10 kHz, 15 kHz, 20 kHz

Power Requirements:  110, 125 V AC , 50 or 60 Hz

Power Consumption:  50 watts

Dimensions (W x H x D): 432 x 222 x 178 mm (17" x 8,75" x 7")