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Are frequencies (boosts/cuts) algebraically additive? Motive Fidelity UltraDeck turntable question.


Active Member
Jul 10, 2023
I am not sure if this belongs here or in the general discussion area. I'm looking at a Music Fidelity UltraDeck turntable but this question is non equipment specific.

The turntable has a 2 1/2 db boost at 12kz.
My loudspeakers have a 5 db boost at 10-11kz.

The loudspeakers are not considered bright nor have I noticed such.

Question: Could the turntable and speakers together create a noticeable elevated treble where I heard non before. I understand ear sensitivity varies. My measured hearing begins rolling off around 12kz and drops sharply in the mid teens.

Moderator please move this if greater traction will be achieved elsewhere.

Appreciate it.

Yes, if you had 2.5 db boost in the TT at 12 khz, and you had loudspeakers 5 db boost at the same frequency you would get a total of 7.5 db boost at that frequency versus flat response.

OTOH, if you've used your speakers a long time, become acclimated to their response and switch in another 2.5 db boost in the treble, you might notice it, but it might not be perceived as a huge difference.
Yes, assuming cartridge, phono preamp and speakers are linear enough (most likely yes)

Linear filter is convolution of an impulse response with a signal. In Fourier space that means you are multiplying their spectra. We usually think of amplitude spectra in a log scale (dB) so multiplication turns into addition. Also note that for multiple filters the order doesn’t matter. So yes, additive
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