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[Swerd]

Baffle step begins at wavelengths roughly equal to the cabinet width. For example, in an 8" wide cabinet, or 0.667 feet, that would be 1130 ft/sec ÷ 0.667 feet = about 1700 Hz. So the BSC circuit would lower all responses above roughly 1700 Hz by 3 to 6 dB. It really has nothing to do with a woofer-to-tweeter crossover circuit, but it is usually built into a crossover board.

Before anyone else corrects this, I'll do it. Ignore the above calculation. My number for the speed of sound in feet/sec must be wrong. 1700 Hz just seems too high.

The correct estimation of the frequency of baffle step in an 8" wide cabinet is as shown in Martin King's article 4560 ÷ 8" = 570 Hz.

 

[annunaki]

Before anyone else corrects this, I'll do it. Ignore the above calculation. My number for the speed of sound in feet/sec must be wrong. 1700 Hz just seems too high.

The correct estimation of the frequency of baffle step in an 8" wide cabinet is as shown in Martin King's article 4560 ÷ 8" = 570 Hz.

I believe it is fairly close. Speed of sound at sea level is 1,116.4 ft/s. You would have to adjust for altitude to be totally accurate.

 

[Guiria]

What is the diameter of your driver, and what is the width of your cabinet? Our ears are more sensitive to baffle step in narrower cabinets because our hearing is better in that range. The baffle step caused by a 15" wide cabinet would be less easily noticed.

There is a downloadable baffle step compensation calculator available online at http://soundhobby.com/download.htm

It is a 3 inch driver in a 9.5 in. tall x 7 in. wide

 

[Guiria]

Is BSC something that should be considered after listening to the speaker without it? Or should I go for it now while still in the construction phase?

The soundhobby calculator offers different steps of correction which leads me to believe that the speakers should be tested for the actual effects of baffle step before the network is made...which would be difficult to install inside a speaker with a 3 inch hole

 

[warnerwh]

If I were to try designing a speaker from scratch I'd ask the guys at Home Theater Shack and AVS DIY forum. HTGuide also has world class speaker designers and builders.

Designing a speaker, even a 2 way is tough to do right. Crossovers may work with the theoretical ideal if you're good at winning lotteries.

I'm not saying you're not capable but if it were me I'd get some help for sure. You could go through hundreds of dollars worth of crossover parts and still have a speaker that doesn't sound right. Those are good drivers and can conceivably sound excellent with the right box and crossover.

Another suggestion is to just copy a design that someone else did. HTGuide has an area call Mission Accomplished with pics and build threads. The mods there are experts on the subject and there's many who will help.

The one thing you can do though is design and build your own sub. You want a real kick *** sub try a couple of SoundSplinter RL-P 18's in a ported enclosure. Forget the commercial stuff if you want to have fun and save a bunch of money.

Best wishes on your speakers.

 

[Swerd]

Is BSC something that should be considered after listening to the speaker without it? Or should I go for it now while still in the construction phase?

Yes, you should go for BSC in the construction phase. Often when people are designing their own crossover, they listen to the speaker mounted in its cabinet, while a mock-up crossover sits outside the cabinet with wires running inside to the speakers. Crossover parts are simply clipped together without soldering anything yet until a final design is made. Yes, it is necessary to make the crossover board small enough to fit inside the cabinet - not always easy .

The soundhobby calculator offers different steps of correction which leads me to believe that the speakers should be tested for the actual effects of baffle step before the network is made...which would be difficult to install inside a speaker with a 3 inch hole

If you already know where you will place your speakers, relative to the wall behind them, you can make an educated guess about how much BSC to use. If the speakers are going to be very close up against that wall, you can skip BSC. If that distance is going to be roughly 18" or more, use the full 6 dB compensation. If the speakers will be somewhere between 0" and 18", try using 3 or 4 dB compensation.