2) Is there a way to convert box volumes for an aperiodic or sealed alignment that would only affect the lower end roll off of the woofer but not disturb the midrange and transition to tweeter that your crossover is designed for?

3) Do your speaker plans, such as the Pro 3, include crossover designs and if so, do you sell any of the components or recommend a source for such?

Thanks, and I promise not post any more questions for at least 48 hours.

Greggo
Asheville, NC

Clarify please. I don't think I've ever heard that.

Simple explanation, it's like when you yell into a fan it modulates your voice.
Bill W.

One way to reduce IMD is to reduce bandwidth, so if you crossover the woofer to mid at a lower frequency, you'll reduce IMD. I don't really notice it unless excursion is high, so if you're not pushing a midwoofer too hard, it isn't generally a problem. But if you are pushing a subsystem far enough that IMD becomes noticeable, the best way to solve it is by reducing bandwidth. Either crossover the lower point higher or the higher point lower, or both.

• Doppler distortion in loudspeakers
  
• Phase, Time and Distortion in Loudspeakers
  
• Phase Correction - Myth or Magic

::a low frequency tone so a higher frequency cone movement must ride upon this shift, which causes a phase shift.

At a certain point the higher frequencies depending what they are, are ethier going to add,subtract or cancel(within the harmonics of the lows, at certain frequencies and x-over points) causing peaks or notches in the overall operating band width of the response.
Isn't this modulating (the highs am style, aka IMD) In a limited bandwith the response with respect to the lows??

This statement I some what agree with:
::The other is a non-linearity caused when the driver is pushed nearing or (not really) exceeding Xmax,
:: where the voice coil has less drive force because it partially "moves out of the gap.(bad news unless your hitting the bottom plate and/or sliding V.C.back into the front of the gap)
This causes it to become non-linear at high drive levels.(TRUE).

Dont, worry because power compression will set in long before hand which will reduce your output 3-7 db because of voice-coil heating. Even though your amps are at full power and not clipping, so don't
boost your lows if you think there lacking.

Time to get off of here,Mr.Seagrams is calling(so I maybe full of s__t)

Not sure though.

• Crossovers and phase shifts
  
• Baffle spacing, crossovers and phase angles
  
• Phase, delays and offset baffle spacing
  
• Baffle spacing, phase angles and time alignment, revisited
  
• Audibility of Phase
  
• Holism and Reductionism - Fourier Series
  
• Crossover nulls
  
• Horn Phase
  
• Transient Perfect Crossovers
  
• "Can't reproduce a square wave"
  
• A few more useful documents

http://www.6moons.com/audioreviews/zu2/definition.html

The second one that I find even more interesting is the Escalante, which uses compound loading and staggered crossover points, low passing the rear (internal to the cabinet) driver around 80hz and then letting the front driver run well up into the midrange... and claiming that this creates an environment for the front driver to have a controlled resonance of sorts and thus lower distortion and dramatically improve the rise time of the drivers response:

http://www.positive-feedback.com/Is...nte_fremont.htm

I normally don't pay much attention to the HiFi press or commercial markets as I am slowly moving towards a mostly DIY system, but these two systems really got my curiousity up and the reviews are both a fun read.

So the last one got me thinking, instead of taking on the whole mid dome instead of whizzer engineering for super extended range from the woofer, is it possible to take the framework of Scott's design, and compound load a second B&C 12TBX100 in front of it and run it all the way up to 90hz or even up to 3-600Hz depending on your overall system design goals and the other drivers involved. Thinking about Scotts take on the frequency ranges that constitute hall valume, slam, punch, etc... wouldn't it be nice to have a stereo pair of bass towers that cover it all before handing off to an upper-bass/lower-mid driver in another cabinet that starts the final stage of the journey to a full range system. Of course, that's if there is something to Tierry's patents worth cloning (for our own, non-commercial use of course).

Anyways, these two products and their accompaning reviews/descriptions/patents go into territory I have not seen discussed on the various diy forums before, most of the time these things are a big yawn for me and I much prefer the forums, these two struck as worth looking at as closely as possible.

Regards,

Greg Jensen
Asheville, NC