DIY - MFAQ2

The Repository->DIY->The Most Frequently Asked Question in DIY Audio (part 2) 

Q: I found a few designs on the internet that I think I would like to build.  But will they really sound as good as the speakers in the HiFi store?

A: Depending on which design, the general consensus is: "Yes, they do sound as good or better than retail speakers, and they don't cost nearly as much."  

Q: So if I build Project X, Y, or Z, then I'm effectively saving myself tens of thousands of dollars.

A:  Well, hold on there.  While there is certainly some price inflation on boutique speakers, you should really consider the craftsmanship involved in very expensive speakers.  Such speakers are rarely just wooden boxes, but are often works of cabinetry art, using techniques that would take a hobbyist hundreds of hours to do--if he had the tools.  On the other hand, there are a lot of mid-fi commercial speakers, ones under, say $5000, that are merely rectangular boxes (albeit well-braced and damped).  And a good DIY design will definitely give such a mid-fi commercial speaker a run for its money.

Q:  But I don't want just "mid fi."  I want the absolute best! 

A:  Well, before you go making judgments, why don't you try building a DIY design, listen to it in your living room, then decide what you consider "the absolute best." Chances are, you'll be surprised how good $300-800 in parts can sound.  With audio--as with many things--there are points of diminishing returns. That is to say: "How much better does a $30,000 speaker sound than a $3000 one?

Q: Fine, I've decided I am going to build Project ABC.  Now, it calls for driver X, but driver Y is on sale and is the same size.  Plus, driver Y looks nicer.  Can I just swap driver Y for driver X in the design?

A: Driver choice is not merely cosmetic.  This isn't like putting new rims on a car.  Even though drivers may be the same size, or may have the same Ohms load, they can behave completely different sonically and mechanically.  If you do not use the same drivers the designer intended, the design will not sound as good as the designer intended.  In fact, it could sound really, really bad, or could cause your amplifier to shut down--and it wouldn't be the designer's fault!

Q:  OK, OK, so I have to use the same drivers.  Now, what if I don't like the way he did his cabinet.  I think I would like to build it much slimmer/ taller/ shallower/ deeper.  Plus, I think the woofer/ midrange/ tweeter would look better if the designer had put it more towards the top/bottom/left/right/center.  Can I make these changes to his design?

A:  You should definitely ask first.  Cabinet design is essential in designing a "speaker as a system."  If the cabinet isn't the right width or height, your build could end up with really thin or bloated bass.

Q:  Oh no!  Not the bass!  I want good bass!

A: Of course you do.  Everyone loves bass ;-)  Now, just as changing cabinet dimensions can cause big changes in the sound, so can changing the layout of the drivers.  Driver layout is almost always very carefully thought-out (and often computer simulated) by the designer to get optimum benefits from the drivers themselves, and their interactions with each other.

Q: So you say I'm supposed to build it to spec?  

A: Yes.  Although building speakers does seem fairly simple, you will learn that there are a lot of quirky building techniques you will have to have to figure out as you go along.  You're better off grappling with those challenges before you try to tackle the perplexing task of designing a crossover.

Q: What kind of "building techniques" will I have to learn?

A:  Well, first of all, I hope you're comfortable with the following power tools: circular saw, jig saw, drill, and router at the very least.  You're going to get very good with a router, learning how to do circles, roundovers, chamfers, flush trims, and rabbets.  You also have to be able to use a soldering iron.  Then there are the manual skills, especially joinery and sanding--you will do a LOT of sanding.  (And all of this happens before you even get to paint or veneer your cabinets)

Q:  How long will it take to build my first speaker?

A:  There is no set answer to this question.  But it seems that most first-time builders take at least a month or two to construct their speakers (that is, assuming they don't have too many family and work responsibilities).

Q:  You're making this sound like not a lot of fun.  Why would anyone do this?

A:  Like any hobby, it's meant to be enjoyable and involving; and it is.  It's gratifying for a lot of people to build something with their own two hands, in an age where so much is done sitting at a desk or behind the wheel of a vehicle.  The end result is also extremely enjoyable, as we talked about before.  It's not a terribly expensive hobby, once you get past the initial investment in tools.  Probably the biggest drawback of the hobby (aside from the steep learning curve you're now becoming aware of) is that people can only fit so many speakers into their house.  So if you really do get addicted, chances are you'll have more speakers than you can actually listen to.  But hey, there could be worse predicaments to be in in life.