This is the "flat” response curve produced by a theoretically perfect loudspeaker ...as your ear hears it!
Surprising? What's more, even that curve would change dramatically with the loudness of the music. That's because your hearing changes with sound pressure level, diminishing your ability to discern bass and treble tones.
So, when you adjust your speaker system and amplifier tone controls to the way you prefer to listen to music in your home, that musical balance is immediately disturbed the moment you turn the level control of your amplifier for softer or louder output.
This happens with all speakers...except BIC VENTURI speaker systems with exclusive Dynamic Tonal Balance Compensation (pat. pend.). A special circuit is incorporated in our speaker systems that measures the amplifier power being delivered to the speaker and automatically adjusts the frequency response of the speaker to the speaker output level. This means that the sound you hear remains aurally "flat," regardless of how loud or soft you play your music. This is a more sophisticated and accurate method of solving the problem than the simple loudness contour switch on an amplifier which is a fixed rate device. That type control can never be effectively matched to speakers with differing characteristics.
This is just one of several exclusive engineering developments you will find in BIC VENTURI speaker systems to insure clean, extended bass; smooth, distortion-free mid and treble response; wide-angle dispersion for uncritical speaker positioning and room placement; high efficiency and high power handling capability for wider musical dynamic range and better amplifier performance.
(Source: Audio magazine, Jan. 1977)
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