I'm not an expert but I've built a few speakers. I've been modeling greenboy like designs for the past few weeks because I wanted a cab with different dimensions. IMO, he optimized the port for the dimensions of the cabinet Changing the dimensions requires some consideration of how the port will be implemented. It's not rocket science but does require some amount of consideration and modeling. Building speakers is fun but at this point in time I'd rather spend more time working on music, guitar, and bass instead of in front of the table saw. I decided to not do a build but that does not mean I don't think it's not a worthwhile endeavor.
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Fearless/full build question
- Thread starter Kirk Bryant
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Indeed, and some legacy designs appear to have a minimal amount of time spent in the design phase.
the main limitations to baffle size is the size of the LF speaker and the size of the amplifier sitting on top of it. It's simple for less diffraction you
want the baffle as small as ppossible. baffles are made wider to accommodate wider amplifiers. 19.5 racks or tube heads are 24" , 26.5" or 29. otherwise the width of the wood and the speaker itself is the limit. for better off axis the smaller the baffle the better. basically with a ideal vertical alignment of all the drivers the baffle could be pyramid shape to reduce in size for smaller drivers unfortunately amps don't sit well on pyramids so tradeoff is made. smallest part of the cab would match the width of the head. and to eliminate diffraction the smaller drivers are offset to one edge which
reduces diffraction to one side of the driver. the other side just deals with the width of the baffle. hifi speakers don't have amps that sit on top. so you can go true vertical and have very small baffle for smaller drivers. without changing topic it's only reason I see a use for powered speaker and having a seperate preamp on the floor. to have a smaller baffle so the amp doesn't have to sit on top and require a larger baffle to accommodate it.
want the baffle as small as ppossible. baffles are made wider to accommodate wider amplifiers. 19.5 racks or tube heads are 24" , 26.5" or 29. otherwise the width of the wood and the speaker itself is the limit. for better off axis the smaller the baffle the better. basically with a ideal vertical alignment of all the drivers the baffle could be pyramid shape to reduce in size for smaller drivers unfortunately amps don't sit well on pyramids so tradeoff is made. smallest part of the cab would match the width of the head. and to eliminate diffraction the smaller drivers are offset to one edge which
reduces diffraction to one side of the driver. the other side just deals with the width of the baffle. hifi speakers don't have amps that sit on top. so you can go true vertical and have very small baffle for smaller drivers. without changing topic it's only reason I see a use for powered speaker and having a seperate preamp on the floor. to have a smaller baffle so the amp doesn't have to sit on top and require a larger baffle to accommodate it.
I can see your points and weight distribution means a lot, but can a crossover weigh more than a 1/4 Lb cheeseburger? Perhaps it can, but I can't see it being a significant % of total cab weight. Then again, if you are designing a cab, you might as well lower the center of gravity as much as you can since it's free, except for a few more inches of wiring.
I don't know about all crossovers but I just one a friend built in my hand the other day and I'd guess it weighed at least a pound or two.
So true. The form factor should fit your needs in physical ways as well as sonic performance. I was perfectly happy with Fearless 110 and 210 cabs ... until I fell more in love with a new amp that would not safely fit atop either cab. I moved on to a Bearfaced BB2, which uses a high performance 12 in a slightly oversized rectangular box that is perfect for me (physically and sonically). I've been thinking about moving to Bearfaced's Super Midget, which is about 60% of the box size with the same 12. Comments on TB are that the SM doesn't produce the "big ultra lows" of the BB2. So that's a perfect example of @BogeyBass statement.
Passinwind
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- Dec 3, 2003
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It's always about tradeoffs. Suppose we take a fEARful 15/6 up to 5 cu ft from the designed 3.8 cu ft and keep a more or less optimally flat alignment:
Nice, we get 2dB of added output between 40 and 50Hz.
But we lost 50 watts of power handling at 32Hz. And we now have some porting and crossover homework ahead to optimize for the new cab size, assuming we want to be as picky as Dave Green was about that stuff. If we go to 3.4 cu ft we get a new set of tradeoffs. Which one is "better?" Better for what?
