Well, I just spent the evening going through my components connecting and disconnecting wires in an effort to find a very nasty humming noise going through my left front channel speaker and subwoofer. I finally found the culprit: my Audio Control Phase Coupled Activator. It's a stand alone component which houses a crossover circuit with a base enhancing circuit. I don't know what's wrong with it, but when I remove it from my system, everything's fine. This dismays me because I've had if for years and have always been quite happy with it.
After I took it out of my system and began to recalibrate, I came upon the real reason for why I'm now writing this thread. I set up my subwoofer using a Paradigm X-30 crossover unit that came with my Servo-15 a long time ago. Calibration was done with the Avia test disc using all the test tones. I just got this disc recently, so have never really completed the audio test tones with my setup. I got to the "Low Frequency Sweep" which outputs a test tone starting at something like 200Hz and works its way down progressively to 20Hz. The idea is to have a smooth transition between your satellites and subwoofer in the crossover range, with no significant dropouts, as well as testing the ability of the subwoofer to reach the lower range. My crossover is set at for all channels. To my astonishement, as the sweep neared approximately 105Hz, the sound level dropped significantly, and didn't rise again until about 70Hz. I refused to believe that this could be due to my satellites (Paradigm LCR-450 for all channels) not reaching down that low since the spec on them says +/- 2dB from 70Hz-22kHz with a low freq extension of 45Hz (DIN). From that I would gather the response of the speaker would be rock solid down to at the very least, 70Hz. To get to the point, I went against my better judgement and moved the crossover up to 120Hz. The frequency dip disappeared and the transition for the test tone was smooth.
Normally I wouldn't care about this, but I have to wonder why the speakers don't reach down to even near where the spec claims. I also would prefer to have a crossover near 80Hz or lower, as per the THX requirements. I would just feel better about my inablility to locate the base source with the crossover being lower. I'm worried that if I buy a new receiver that it might not give me the ability to crossover at 120Hz (like my friends Yamaha which crosses everything over at 90Hz.) I was interested in the Pioneer Elite 45TX, or the Sony Da4ES.
After I took it out of my system and began to recalibrate, I came upon the real reason for why I'm now writing this thread. I set up my subwoofer using a Paradigm X-30 crossover unit that came with my Servo-15 a long time ago. Calibration was done with the Avia test disc using all the test tones. I just got this disc recently, so have never really completed the audio test tones with my setup. I got to the "Low Frequency Sweep" which outputs a test tone starting at something like 200Hz and works its way down progressively to 20Hz. The idea is to have a smooth transition between your satellites and subwoofer in the crossover range, with no significant dropouts, as well as testing the ability of the subwoofer to reach the lower range. My crossover is set at for all channels. To my astonishement, as the sweep neared approximately 105Hz, the sound level dropped significantly, and didn't rise again until about 70Hz. I refused to believe that this could be due to my satellites (Paradigm LCR-450 for all channels) not reaching down that low since the spec on them says +/- 2dB from 70Hz-22kHz with a low freq extension of 45Hz (DIN). From that I would gather the response of the speaker would be rock solid down to at the very least, 70Hz. To get to the point, I went against my better judgement and moved the crossover up to 120Hz. The frequency dip disappeared and the transition for the test tone was smooth.
Normally I wouldn't care about this, but I have to wonder why the speakers don't reach down to even near where the spec claims. I also would prefer to have a crossover near 80Hz or lower, as per the THX requirements. I would just feel better about my inablility to locate the base source with the crossover being lower. I'm worried that if I buy a new receiver that it might not give me the ability to crossover at 120Hz (like my friends Yamaha which crosses everything over at 90Hz.) I was interested in the Pioneer Elite 45TX, or the Sony Da4ES.