My commercial 10" sub has a crossover fixed @ 90hz on both the line and low-level inputs. It's too high and causes the bass to be directional and slightly boomy. I think 50hz would be better. The simplest solution I can think is to put a coil on the driver. I don't mind the 'hole' between 50 and 90hz because there are other speakers in the system to cover the deficit.
Also, I have a theory as to what may be compounding my problem - roll off.
My current system comprises of 7 speakers; 10" inch rear sub, 2 x 6.5" front subs, and 4 x floor-standers with 6.5" woofers. As we all know crossover points are not absolute - there's a slope!
You guys are the ones who know how to operate a slide rule but work it out @ 6dB per octave . . .
Bear with me, I'm formulating this theory as a type . . . there may be holes. Taking 100dB as the listening level, filter the 10" sub @ 50hz and at 100hz it is only 6dB down. 100hz is within the front sub's range, add their contributions, +3db, +3db. Crossed at 120hz, any 6.5" woofer in a 30l cabinet will be only a couple of decibels down at 100hz . There are four of them, +3db.
Is my problem that at 100hz I have 7 drivers making a significant contribution but at 35hz I have only one?
Also, I have a theory as to what may be compounding my problem - roll off.
My current system comprises of 7 speakers; 10" inch rear sub, 2 x 6.5" front subs, and 4 x floor-standers with 6.5" woofers. As we all know crossover points are not absolute - there's a slope!
You guys are the ones who know how to operate a slide rule but work it out @ 6dB per octave . . .
Bear with me, I'm formulating this theory as a type . . . there may be holes. Taking 100dB as the listening level, filter the 10" sub @ 50hz and at 100hz it is only 6dB down. 100hz is within the front sub's range, add their contributions, +3db, +3db. Crossed at 120hz, any 6.5" woofer in a 30l cabinet will be only a couple of decibels down at 100hz . There are four of them, +3db.
Is my problem that at 100hz I have 7 drivers making a significant contribution but at 35hz I have only one?
You can do a passive line level low pass. 1st or second order. That's cheap and easy. You may need to experiment a but to figure out where the low pass point needs to be.
https://www.t-linespeakers.org/tech/filters/passiveHLxo.html
https://www.t-linespeakers.org/tech/filters/passiveHLxo.html
Another option is to open up the electronics, locate the circuit that does the low pass filtering and replace the relevant components. You can recognize the relevant bits by the presence of an opamp and two MKS capacitors.
Putting a coil in series with the woofer does not really work. It will typically cause a bump at approximately 100 Hz.
Putting a coil in series with the woofer does not really work. It will typically cause a bump at approximately 100 Hz.
Dependent on your overall setup, connecting a line level active crossover would allow you to discover optimum crossover points. It may give you so much flexibility that there is no going back.
The high pass filter in the sub may be something simple as a second order active filter. This could probably be modifed with a couple of resistor swaps.
The high pass filter in the sub may be something simple as a second order active filter. This could probably be modifed with a couple of resistor swaps.
It's not the main speakers. The system sounded great when I had an Audica Microsub3 (set at 50hz as my rear sub http://www.audicapro.co.uk/microsub.html
The system sounded great. But I moved the Audica to my desktop system replacing it with a Solid Solutions PB100 which has a fixed crossover frequency.