LSi-15: I can explain what these data mean?

Bernal

Hi,
I have LSi-15
I can explain what these data mean?


Crossover (mid-high array):
Driver 1: HPF at 150Hz 6dB/oct, LPF at 800Hz 12dB/oct.
Driver 2: HPF at 150Hz 6dB/oct, LPF at 2.4kHz 12dB/oct.
Tweeter: HPF 2.4kHz 18dB/oct. Driver 1: HPF at 80Hz 12dB/oct, LPF at 800Hz 12dB/oct.
Driver 2: HPF at 80Hz 12dB/oct, LPF at 2.4kHz 12dB/oct.
Tweeter: HPF at 2.4kHz 18dB/oct.
Crossover
(subwoofer) LPF at 150Hz 12dB/oct.

mhardy6647

HPF = high pass filter -- 150 Hz at 6 dB per octave: this is a first order crossover slope. It is down 6 dB one octave below 150 Hz, down 12 dB two octaves below 150 Hz, and flat at 150 Hz and above.

LPF = low pass filter. 12 dB/octave means a second order crossover slope; down 6 dB a half-octave above 800 Hz; 12 dB an octave above 800 Hz, etc.

etc., etc., for the other crossovers.

EDIT: An octave is a doubling (or halving) of frequency from one tone to the next octave. Thus, one octave below 150 Hz is 75 Hz; one octave above 150 Hz is 300 Hz; one octave below 800 Hz is 400 Hz, one octave above 800 Hz is 1600 Hz, etc.

A "first order" crossover has one "pole" (filter unit), a capacitor for an HPF, an inductor (coil) for an LPF and a slope of 6 dB per octave. A second order crossover has two poles (inductor and a capacitor) and a slope of 12 dB per octave, etc. http://en.wikipedia.org/wiki/Piano_key_frequencies

Bernal

mhardy6647 wrote: »

HPF = high pass filter -- 150 Hz at 6 dB per octave: this is a first order crossover slope. It is down 6 dB one octave below 150 Hz, down 12 dB two octaves below 150 Hz, and flat at 150 Hz and above.

LPF = low pass filter. 12 dB/octave means a second order crossover slope; down 6 dB a half-octave above 800 Hz; 12 dB an octave above 800 Hz, etc.

etc., etc., for the other crossovers.

EDIT: An octave is a doubling (or halving) of frequency from one tone to the next octave. Thus, one octave below 150 Hz is 75 Hz; one octave above 150 Hz is 300 Hz; one octave below 800 Hz is 400 Hz, one octave above 800 Hz is 1600 Hz, etc.

A "first order" crossover has one "pole" (filter unit), a capacitor for an HPF, an inductor (coil) for an LPF and a slope of 6 dB per octave. A second order crossover has two poles (inductor and a capacitor) and a slope of 12 dB per octave, etc. http://en.wikipedia.org/wiki/Piano_key_frequencies

Thanks for your reply.
Very complete, but as you explain to a mortal.
What is the practical use with a Denon AVR 4308CI and a Velodyne Optimun 12 subwoofer.

McLoki

Bernal wrote: »

Thanks for your reply.
Very complete, but as you explain to a mortal.
What is the practical use with a Denon AVR 4308CI and a Velodyne Optimun 12 subwoofer.

The crossovers you are quoting above is the speaker crossover or where the signal goes when it enters the back of the speaker. The signal is full range at the back of the speaker and then it is divided (by the crossover) to go to the various drivers within you speaker.

in your LSi15 - the crossover sends signals to the 8" woofer, each of the 5.25" drivers has its own HPF (this is the cascade tapered array) and the tweeter.

The crossover in your receiver and your sub would only affect what comes into the speaker (i.e. - maybe the speaker would not actually receive a full range signal because of another crossover in place before the actual speaker) But will have no affect on the crossovers in place inside the speaker.

Michael