Thiel Owners

Jan - I hope I am not dominating this forum, but I enjoy sharing what I've learned. I have compared single and stereo SS1 and SS2 subwoofers in my studio with PowerPoint 1.2s as room mastering monitors. The stereo pair presents a decidedly more believable image. Note that the PPs cross over at 80Hz, which includes more upper information than many applications.

John Schwenker - I am intrigued by your second-order experience. Soon I will have my Metric Halo ADA rig back up and will devise a second order XO at 80Hz for low and high pass. It has a high probability of better transient performance than the PXO solution of 4th order high and low. I will be able to measure the net output to ascertain that the subwoofer can produce that 12dB roll out. The PPs produce a textbook 12dB roll out. BTW: second order slopes share some prestigeous company.

@tomthiel, not at all! This is what makes this forum so great, people sharing their experience and knowledge. I'm definitely leaning towards a pair of subwoofers.

Hi tomthiel,

Yes, quite a few well regarded speakers over the years/decades have used/still use second order crossovers to the woofer. Given the nominal 180 degree phase delay, the most satisfactory results are generally gotten by inverting the relative phase of the wires to the woofer. This works well for some frequencies away from the fc but not so good for time alignment in the vicinity of fc. Here (with time shifts available) I’ve stood that on its head a bit by not inverting and delaying to seek best phase blending at fc.

I may be telling you a bit more than I know for sure, partly as discussion stimulation. (smile) It has been a few years since I looked more carefully at it. I just reviewed some old modeling spreadsheet work where I was showing myself that if I differently pro-rated or scaled the importance of the time alignment at frequencies stepping away from fc in half octave jumps, some of those schemes would start to suggest I might be better off with something headed toward an additional 35 degrees or so of phase shift. I thought that result was pretty small for how highly speculative I was being… and decided not to pursue it even as a listening experiment.

The overview message is still that, if one is willing to go there, DSP devices give us some greater freedoms to customize that integration than we’ve had in the world of analog crossovers.

Yours, John