Crossover: ESLs and a Grotto

[Charliemike]

So what exactly does one do when you have a pair of ESLs that are supposed to be crossed over at 95Hz and a sub (Grotto) that only goes to 80Hz? Cross it at 80Hz and then lose about 15Hz worth of information? Or does this combination mean that there's overlap?

Dammit I'm so confused

 

[roberto]

So what exactly does one do when you have a pair of ESLs that are supposed to be crossed over at 95Hz and a sub (Grotto) that only goes to 80Hz? Cross it at 80Hz and then lose about 15Hz worth of information? Or does this combination mean that there's overlap?

Dammit I'm so confused

Hola Charliemike...just put the crossover knob of the sub at the highest cutting frequency...it will match your Els with no problem...the Grotto frequency response is flat at 150 Hz...at 90 Hz it would be less than 1 dB the cut...try it, you might like it. Just enjoy the sound of you system and forget about this minor specs and confusing :music: problem...happy listening,
Robertol

 

[Sambob2]

Charliemike,

Most ESL's are going to be crossed over to the sub at about 80Hz anyway so you should be ok with using this as a crossover point. Check the manual for the Grotto also, depending on the main speaker in use, they recommend crossing over at a lower frequency if you do the math. Say for instance that your main speaker is rated to go down to 43 Hz (-3dB point). The manual states that you take this number 43 and multiply it by 70% for the crossover point. 43 X .7 = 30.1 Hz...a little to low if you ask me. I would go higher and crossover at 65 or 80 Hz.

Experiment a little with each setting and hear which setting suits your listening best.

 

[ralflar]

charliemike,

You would not create a frequency gap of 15Hz. These filters are not of the boxcar type, they fall off or rise with a slope of so many dBs per octave. A 24dB/octave low-pass filter with an 80Hz cutoff frequency would let 1/4th of the signal amplitude pass at 160Hz and 1/16th at 320Hz. A 100Hz 6dB/octave high-pass (low-cut) filter still produces about half the signal amplitude at 50Hz. Both the low- and high-pass filtered signals will be added, more or less. If you do not separate the low-pass and high-pass cutoff frequencies you will probably exagerate the frequency range in which the low-pass tapers down and the high-pass ramps up. Filter slopes, cutoff frequencies, location of the individual speakers, and of course the room, will all affect the overall frequency response. To get it right you'd have to measure and tweak.