Coaxial midrange/tweeter drivers for car audio have time alignment issues but don't sound terrible. My suspicion is that powerful bass frequencies travel all through the cabinet ricocheting of end points and arrive at midrange drivers as spurious noise, far more damaging to perceived midrange audio quality. Also, internal speaker reflections occur at tiny fractions of bass frequency wavelengths exciting much higher frequency content in a cabinet (unless it's a transmission line design). That's where RF and acoustic energy analogies part ways. Low frequency energy can vibrate smaller structures to be transformed into higher frequency content, think higher frequency buzzing from those trunk subwoofers blasting rap.
Does mixing in the RF world apply to acoustics? If it does than a 60hz cabinet horizontal plane resonance distorts midrange by +/- 60Hz while high frequency vibrations would obviously be much more damaging. Another thought is that the cabinet is small enough that it may not effectively couple that low of frequency, or the midrange driver mounting is to small an aperture to effectively couple those frequencies. Dali does some work on driver rigidity to eliminate resonances and distortion.
I do believe the horizontal plane distortion at low frequencies remains as an equal and opposite reaction but is not coupled into the cabinet material. Hence the directionality of the Gaia footers delivering optimium results.
While I'm no expert on the subject, Herbie's footers would seem to work great on hard wood or tile since the lossy material comes in better contact with the hard surface as opposed to carpet. Mapleshade products are interesting and I share Tom's sentiments on the blocks. Given how lively the DI cabinets are, it's not surprising an engineered sandwiched footer makes such a difference. I suspect first reflection point treatments on the walls and ceiling could fall into the same level of improvements. Room correction still delivers large improvements for me, but will find out more as I treat my room.
Merry Christmas everyone. Really enjoyed this thread over many months.
Does mixing in the RF world apply to acoustics? If it does than a 60hz cabinet horizontal plane resonance distorts midrange by +/- 60Hz while high frequency vibrations would obviously be much more damaging. Another thought is that the cabinet is small enough that it may not effectively couple that low of frequency, or the midrange driver mounting is to small an aperture to effectively couple those frequencies. Dali does some work on driver rigidity to eliminate resonances and distortion.
I do believe the horizontal plane distortion at low frequencies remains as an equal and opposite reaction but is not coupled into the cabinet material. Hence the directionality of the Gaia footers delivering optimium results.
While I'm no expert on the subject, Herbie's footers would seem to work great on hard wood or tile since the lossy material comes in better contact with the hard surface as opposed to carpet. Mapleshade products are interesting and I share Tom's sentiments on the blocks. Given how lively the DI cabinets are, it's not surprising an engineered sandwiched footer makes such a difference. I suspect first reflection point treatments on the walls and ceiling could fall into the same level of improvements. Room correction still delivers large improvements for me, but will find out more as I treat my room.
Merry Christmas everyone. Really enjoyed this thread over many months.