First Impressions with an Active Crossover

[Rick U]

The tweeters are okay. I think The sound sweeps might be conservative so they have less risk of damaging the tweeters. I made a target where I dragged the curve further up the frequency. Cymbals were too hot.

[chessman]

Originally Posted by Rick U

Well I've had some time to play around with different setting and decided to measure one of the results that sounded pretty good.
This is with everything crossed at 50htz and a 12 degree slope. Looks like there is plenty of room for improvement right?

Rick, that 40H peak and 80 H suck out are related. The fact that it is happening in the neighborhood of your cross-over suggests the subs and the mains are interfering with each other. What is the -3db point of your speakers (the frequency rating where the bass volume has dropped off 3 dB)? Have you tried adjusting the relative phase on the subs while watching this real time scan? Relative phase is really "time travel" in that it is adjusting the sub wave front to arrive when the mains wave front does in order to reduce destructive interference from two different sources. You are getting close.

[Rick U]

My measurement software is not live. It's part of Dirac Room Correction and set up takes a lot of time. Do you know if there is software for the mac that is live? I have a decent usb microphone.

[junker]

I'd maybe try to raise the cross over point slightly and/or use a gentler crossover slope.

[Rick U]

Thanks guys. I have tried switching the phase and I'm not sure what the 3db drop is. Is that published with the specs of most speakers? I wish I had a recording of the test sweep. Maybe I can fool Dirac into playing the sweeps while I analyze with a different computer or i devise.

[jdandy]

Originally Posted by Rick U

I wish I had a recording of the test sweep.

Rick.......Do a Google search for the Rives Audio Tests CD2. It's $21.00 and you can order it online. This disc has all the test tones you will ever need. It has 1/3 octave test tones from 20 Hz to 20 kHz. The test tones are very precisely calibrated for a flat response. Each tone is a single track, so that once a room mode has been found, one can put the track on repeat mode and determine where the "hot spots" or areas of highest sound pressure exist to properly treat the room or make speaker location adjustments.

[junker]

The Stereophile Test CD Warble Tone series would be good for this:

Test CDs - Source Interlink Media



@Dan: Has Santa's little helper been naughty or nice? ^

[Rick U]

I had an hour (rare for me) to try some different crossover points. My plan was to get the subs sounding as good as I could by ear then let Dirac do corrections from there. The high pass is now set at 40 and the low pass at 50 w 6db slopes. I never set up Dirac because I got super busy listening to music and forgot all about measurements. By the time I looked at my watch 3 hours had passed and I was in a good mood. Next time I'll try harder to stay focused.