So in a ideal world but only for performance sakes not aesthetically with a blank sheet what sort of speaker design would you have built money no object to cover the audio spectum 20-20khz and why ie size drivers, number off ? When my cv s go pop I would like a project.
20hz is something of a piped dream, as much as some people see it as a goal, it is not really necessary for music, and though nice for movies, equally not really necessary.
I have an unusual system in that I have two amps and two pair of speakers. My old set of speakers, which I keep because having them and using them is worth more than the small amount of money I could get for them, have 12" bass drivers and horn Midrange and Tweeters. My main/new speakers have 2x8" bass drivers each. I would rate the 12" DIY speakers at best at 35hz, and at -6db, the 2x8" are rated at 28hz. During action movies, I've felt bass impact that cause the upholstery on my chair to flex under the impact. I've felt bass so intense the whole room shook. So, exactly what is it I'm missing again????
As to speaker designs, this is my latest -
Three of the design goals were -
- Separate cabinets for the low bass
- Trapezoidal shape
- Deep bass impact, but not over bearing or droning bass. I want deep but tight.
In the modern world most people want very slender unobtrusive cabinets, so this would not work for them. However, being Old School, and not minding big monkey coffins, I'm OK with a 10" bass driver. Especially given that I have 12" bass drivers now.
In the drawing, the grid is 2.5" per square. So as drawn the cabinets are 37.5 inches high and about 15 inches wide at the bottom, though if I ever build them, those dimension would likely change out of necessity.
The design on the left is a 3.5-way. The 10" runs in parallel with the 8" at the lowest frequencies, probably below about 200hz. And NO, it is not a Subwoofer, just a straight up woofer.
The design on the right, is a 3-way, 10" bass, 2x4" midrange, and a tweeter.
Using the Relative Size information we have, we discover a 10" is relatively 11.65, and 2x8" is 13.52. We can divide this how we choose, but 11.65/13.52 = 0.862, meaning that a 10" bass driver is 86.1% the size of 2x8" bass drivers. While slightly smaller, a 10" bass driver will inherently go lower.
Given the large diameter bass driver and the large cabinet size, this would likely have loud and deep bass response. Given the speakers I was considering for this design, they have a Sensitivity of 87db, and a rated bass response of 27hz, though with room gain, likely a bit deeper. I think we could arrive at a design that was flat to 27hz, and given typical speakers, we could estimate a -6db response of 22hz. Whether that would prove out in the final design remains to be seen.
While the specs on the matching 8" driver are very close to the 10" bass driver, two 8" cost US$100 where as one 10" cost US$80. Given that you need double that amount for both speakers, I save $40.
Which is the best choice for any given person is up to that person. As it stands now, I'm going with 10" bass drivers, though a similar design could be accomplished with 2x8" bass drivers. If a narrow face to the room is important, then 2x8", if that is not such a great concern, then 1x10".
For what it is worth.