Those 6.5" coaxial speakers have an "effective frequency response of 40 Hz to 20Khz" and a sensitivity of 90.
https://www.kicker.com/cs-coaxial-speakers-65
"Effective frequency response" is a term used when the bass response rolls off at a much higher frequency but the speaker is still able to reproduce sound at the lowest frequency (though you'd barely hear it.) In the case of these Kicker's I suppose the bass response is somewhat flat until it gets to around 80 Hz and then sharply drops off, petering out at 40 Hz. I couldn't find the frequency response chart.
In contrast those Pioneers have a frequency response of 28 Hz - 36KHz and a sensitivity of 92. That means they will have better bass response and play a tad louder. These speakers have bass that is flat until about 60 Hz and then drops off to 20 Hz. Pioneer rates frequency response as 28Hz to 36Khz [-20 dB]. That means the low number, 28 Hz, is where sound pressure levels dropped off 20 dB from flat, and the high number 36KHz is where high frequency response drops off 20 dB from flatness . Notice bass frequency is flat at about a sound pressure of 90 dB until it gets to about 60 Hz than starts dropping. It crosses 70 dB at about 28 Hz. So Pioneer fixes the lower end of bass response at 28 Hz.
Here is the frequency response chart of the Pioneers (TS-A6966R):
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