DIY - Dayton III

The Repository->DIY->Dayton III 

 Story behind the project

Building a set of loudspeakers myself is something I have wanted to do for 12 years.  It started back in high school, when I checked out some books from the library, and tried to figure things out on my own.  The books left me with two impressions.

1.  Since the books were published decades ago, the designs were all really dated-looking.  That right there sort of killed my desire to go any further.  After all, what reason did I have to invest significant amounts of time and money into something that looked as tacky as someone's garage sale throwaways?

2.  The remainder of the books were plastered with graphs, which pretty much made no sense to me.

So I humbly returned the books to the library, and tried to forget that I ever wanted to try building speakers in the first place.

A few years later, while living in California with a friend for a summer, the two of us decided to try to build a speaker out of some [nice-looking] parts we saw at a nearby electronics store.  We thought we'd do something brilliant and put the drivers in an unusual enclosure.  The result sounded awful (but looked really cool).  We quickly learned that to assume that you can buy some nice drivers, plop them into any old enclosure, and expect it to sound like anything is a shot in the dark at best.  After that experience, I was pretty sure I was best off leaving speaker building to the pros.

Fast forward to now

I am a frequent reader of the website hackaday.com.  I thoroughly enjoy finding out the ingenious ways people figured out how to use ordinary things in extraordinary ways.  Sometime in October, a guy built an unusual iPod dock.  It had a tube amp driving a homemade speaker.  What grabbed my attention was not the tube amp, but the speaker itself.  While his writeup of the iPod dock was very brief, he mentioned that this attractive-looking speaker was called the Dayton III, and was probably the most popular DIY speaker design out there.  My eyebrows raised.

Here is the aforementioned wacky ipod dock.

Sure enough, the Dayton III is the brainchild of the brilliant DIY speaker designer Wayne Jaeschke, of the website www.speakerbuilder.net.  What really grabbed my attention about the Dayton IIIs was not just that they had been successfully built by many hobbyists, but that a very nice young fellow named Alan Loprete had actually written a walkthrough detailing the steps of building the Dayton IIIs.  Oh goodness, maybe it was going to be possible to build my own speakers after all!

Here are the basic plans of the Dayton III

Here is Alan Lopretes very helpful walkthrough

The plans for the Dayton III (also referred to as the D3) said that they were a good set of speakers for a first-timer to learn the ins and outs of speaker building.  When I first read that line, I felt a bit cocky, thinking, "Oh come on, what kind of ins and out are we talking about here?  It's just sawing some wood, screwing some speakers in, and soldering a few parts to a crossover."  However, after officially completing my first set of speakers, I can honestly say that there are several ins and outs to building speakers that you really have to try yourself--reading about it won't suffice. 

Unlike trying to find information on making a webpage for your dog, or how to adjust to the all-watermelon diet, there are scant resources available on how to build your own loudspeakers.  Unfortunately, there are only about three books on the subject.  The Internet, on the other hand, is a cool new resource that wasn't really available to me 12 years ago.  And while it does have dozens of webpages created by speaker building hobbyists, very few of these people go into the details of how to actually build the speakers.  On the upside, these websites do contain a veritable bevy of DIY speaker plans--which are great to have, once you get the "ins and outs" under your belt. 

Before rushing over to Home Depot or logging into partsexpress.com to buy all the parts, I did as much studying-up on the subject as I could, so I could at least have a theoretical understanding of what I was about to attempt.  (After all, since this was going to cost me $200+, I wanted to be sure that my efforts would really produce something worthwhile)  Finally, my interest in the project was near an obsession, and I knew I was ready to go at it. 

Brief overview

Total elapsed time: about 4 weeks; mostly weekends and 1 night a week

Cost: $160 or so for electronics, $50-60 for wood and various construction materials

Time/brainpower equivalent: winning a moderately-long video game twice

Trips to the hardware store: so many I lost count

Cuts or broken bones: 0

Bouts of frustration: 2 or 3

Cleanup: getting fine sawdust out of EVERYTHING in the workroom

Number of mice in my dad's workroom: dozens

Satisfaction with final product: extremely satisfied

Biggest frustrations

Using a router to cut holes for the drivers

This was my first time using a router.  I borrowed the router and bits from my uncle and my girlfriend's dad, respectively.  My first attempts of trying to do anything with the machine were terrible at best.  To be honest, the thing scared me.  I mean, that bit was turning at 20,000 RPM, meanwhile the room smelled of smoke, and sawdust was being thrown out in a thick stream.  To make matters worse, the driver holes I was attempting to make kept coming out the wrong size.

See, to make round holes in wood is a unique challenge.  You need a jig to do it.  There is pretty much one company that makes this jig; it is called a Jasper circle jig, and it sells for $40.  While everyone swears by the efficacy of the device, I had a hard time justifying spending that much money on something I might only use on one project. 

I had read that you could make your own circle-cutting jig, but the information on how to do it was not to be found.  I tried making one out of hardboard, but (as I said) not only did I keep cutting the holes the wrong sizes, but the hardboard fell apart on me.  When this happened I knew it was time to stop and re-evaluate.  I took a compass from work, and practiced drawing circles on paper until I got the hole and rebate sizes right.  Then, I stopped trying to use the crappy hardboard, and cut a small piece of 1/4" plywood I had lying around.  Finally, I measured the radii of the circles from the EXACT CENTER of the router bit, then I subtracted 1/2 the width of the router bit from the final radius.  Slowing down and thinking through the solution was worth it, because I was immediately able to cut perfect driver holes (and rebates). 

If none of the above made sense to you, that's okay.  I will hopefully someday soon write out a much-needed set of instructions on how to make your own circle jig for the world.

More router issues

Like I said, routers scared me at first.  The one my girlfriend's dad lent me had this metal lever that was supposed to hold the collet in place while you change a bit.  It tended to flap around like a dog's tongue out of a moving car.  Combined with the burning smell in the room and the large amounts of sawdust, the last thing I wanted was for the machine to generate some sort of spark.  So I called up my uncle and borrowed his router.

I thought I was good to go, but I started noticing that the room kept getting smokier and smokier, and the edges of the cuts were getting really rough.  Soon enough, the router wasn't cutting at all, just stinking up the place like an aspen forest fire.  I assumed that I had just burnt out everyone's bits, and considered going to the hardware store to buy the poor generous souls replacements; but first I looked in a book on routers that I checked out from the library. 

My problem was actually very easily solved.  The bits were merely dirty.  All I needed to do was two things:

1.  Use oven cleaner to clean the crap off the bits.

2.  When using the bits, use a light oil to keep things lubricated. 

Once I enacted these two measures, my router problems were a thing of the past, and I was able to route holes lickedy-split.  Seriously, once I got the hang of it, I was amazed at how fast and accurate of a machine it really was.

Put the front baffle on first, not last!

I know I read this several times, but for some reason I did it back-assward.  There are three very good reasons for putting the front baffle on first.

1.  You can align the top and sides to be flush with the front baffle.  This is important cosmetically because the front is the part you look at the most.  Because I put mine on last, I had to spend an hour filing away all sorts of wonky edges to make the front appear flush.

2.  You can mount the crossover components to the back board, THEN put the back board in place, rather than trying to stick things to the back board by reaching through the driver holes.  Actually, I didn't have this problem.  I mounted the crossover components on the back board, then installed the front baffle.  The only drawback is that that crossover is never coming out, because the crossover is larger than the driver holes.

3.  You can easily reach through the driver holes to seal the back board, versus trying to seal the front baffle by reaching around and not being able to see what you are doing.  In order to seal the front baffle, I had to put a hand mirror inside the baffle, then put globs of caulk on a popsicle stick and reach inside and gloop it in place around the edges of the front baffle.  This was VERY messy, and I'm not even sure how well it sealed the cabinet.

Things that went surprisingly easily

Making my own vent

At first I thought I had to be super-careful when getting PVC pipe the right size and shape for the vent.  I went to the hardware store and had them cut it into perfect 8" long pieces, because that was what the plans called for.  Then later on I realized that the vent length of 8" was meant to include the wood it mounted to.  So I had to cut off 3/4" of an inch off each one with a hacksaw.  The edges were jagged, and far from square, so I wondered if it would still work.  When I used some Goop to stick the PVC into the rebates in the wood, I noticed that the Goop dried to fill in the gaps very nicely.  Sure, the vent tube didn't exactly sit at a 90 degree angle, but it didn't matter, becuase that part was on the inside, and was never seen by people.  Flaring the edges of the wood to mete the tube was also very easy (if not a bit fun).  Wayne J at www.speakerbuilder.net gives great instructions on how to do this.

Making your own flared PVC port tube.

Building the crossover

Compared to some other electronics and soldering jobs I've done, this was very easy.  (Let me put it this way, putting new electronics in a guitar is a lot more difficult.)  This was the only step I did at my apartment.  I took my time, and followed Wayne J's instructions, and they came out perfectly.  Of course, I did test them before I mounted them inside the cabinets. 

Wayne's highly effective and practical method of building a crossover is found here.

Parts Express vinyl laminate

Before I even started the project, I debated all my options for finishing the outside of the cabinets.  It seemed to boil down to two options

1.  Veneer - I have never used the stuff, and it seemed like a lot of work (not to mention VERY expensive).  Plus, once it's in place, then it must be sanded and stained and finished--something I can do, but generally suck at.  Plus, stain and laquer stinks up the house for days or weeks.

2.  Spray paint - seemed a bit expensive, but doable.  My biggest fear, however, was that dust would certainly accumulate on the surface as it dried--which would require vigorous amounts of sanding, and would probably never look very slick.  Unless I wanted to construct some sort of dust collection system, it didn't seem like a wise idea.

Then, while perusing the Parts Express website, I noticed that they sold some sort of vinyl laminate with faux wood finishes.  I didn't know what to expect, but it was extremely inexpensive ($18 for a 2x18 foot roll), so I bought a roll of "cherry."  When it came in the mail, my dad looked at the roll and commented that it looked like "sh***y contact paper."  When I tested it out on a scrap of wood, however, everyone's opinion suddenly changed.  It looked like your standard-issue Ikea or Office Max furniture (or any of the faux-wood-finished speakers they sell at Best Buy or Tweeter).  Perfect for a first set of DIY speakers!

When it came time to actually apply the laminate, I studied Darren Kuzma's writeup.  Like everything else, however, it was a trial-and-error process.  I ended up peeling the laminate off the first speaker, re-sanding, and applying a new sheet of laminate--something I could never afford to do if I was using veneer.

Here is Darren Kuzma's writeup on how to work with the stuff.  Decent, but you'll really get it once you just dig in and try it. 

Enough hot air!  How do they sound?

Of course, the question many might ask is, "Why build your own speakers?"  For starters, there is just something intrinsically satisfying about making something yourself and have it work at least as well (if not better) than something you could buy at a store.  Then there is the factor that making things yourself can save quite a bit of money.  I would estimate that making your own speakers [correctly] will end up costing 1/2 to 1/4 the price of comparable speakers at a store.  Of course, that doesn't factor in the amount of time you will put in to make them--but as long as things are progressing with the project, the process of constructing things by hand can be extremely gratifying (if not downright theraputic).

So, since these boxes cost a little over $200 for the pair, we can be fair and say that they cost maybe $110-$120 apiece.  And I guarantee you will not find something that sounds this good for that price at a store.  Since I am not a walking lexicon of loudspeakers, I can't really say to you, "They sound just like a pair of Infinity XYZs or Polk Audio ABCs."  Non DIY people might assume that, since these speakers are quasi-bookshelf and not floorstanding speakers, that they probably don't have much bass.  On the contrary, the low end on the Dayton III is actually deeper than the muscular-looking Cerwin Vega speakers (with 12" woofers) I've been using for the last few years. 

Frank Zappa used to say, "Talking about music is like dancing about architecture," and I often feel that way when I read people's descriptions of loudspeakers.  Nonetheless, I will do my best to give my impressions.

As I mentioned before, the bass on these speakers is VERY impressive.  It gets way down there--far beyond pretty much any other set of speakers I--or anyone else I know--owns (a real testament to good cabinet design).  For instance, I noticed that while listening to the Drum & Bass classic "Circles," the D3s were playing low notes that I simply had never heard before.  What I like about the low end of the D3s is that it's not the kind of bass that feels like you're getting kicked in the arse like an action movie subwoofer (which some people do like; tastes may differ).  Instead, it's a very smooth and musical bass--much better suited to instruments than explosions.  The midrange is probably what they would call "a bit relaxed," which is a very good thing for a living room.  If I go from listening to the D3s to my studio monitors, my ears actually do feel "fatigued" from the monitors putting everything right in my face.  The high end on the D3s is very pleasant.  There is definitely a value to having tweeters up near ear level.  It makes the difference between plain old "listening to some tunes through a box" to "feeling like the performance is in the room" as you can clearly hear the singer's enunciation and the sizzle of the cymbals. 

Now, I can't discuss audiophile speakers without a word or two about imaging and soundstage.  As lifted from the Crutchfield website, imaging refers to being able to hear the placement of instruments and sound (from left to right) in a stereo recording.  Soundstage--a similar idea--is the way that the speakers make the song sound like it is taking place in in the room (imagine the performers playing on a stage in your living room).  As many DIY first-timers have said, until I made the Dayton IIIs, the two concepts were sort of hypothetical to me.  

First of all, the imaging really is very good on these.  I almost feel like it's something I've never really experienced.  I noticed that, on some songs, certain instruments almost seemed to scream, "I'm over here!" from the far left and right.  And I'd think to myself, "Wow, I never noticed that instrument was so far out there."  It's pretty cool, actually. 

I also feel like these speakers have shown me what "soundstage" actually means.  For instance, one of the first CDs I tried out on them was the straightforward (yet very well-recorded) "Around the Fur" by the Deftones.  I couldn't help but notice that the first song, "My Own Summer (Shove it)," actually seemed TALL.  I didn't know speakers could do that!  Also, I have noticed that on well-mixed songs, instruments seem to come from beyond the width of the speakers--almost like a movie screen which somehow could make a movie seem wider than the edges of the screen itself. 

Closing of Chapter 1

There really are a lot of "ins and outs" to building your own speakers.  And because there are so few resources out there on how to properly construct a cabinet, the process of going from "I know how to use a saw and drill" to "look at me, I made my own set of speakers" is like the equivalent of trying to get a car from 0 to 65 mph without a first or second gear.  And no, you cannot grind the thing into 3rd gear and hope it gets there.  You pretty much have to make your own first and second gear.  The good news is that once you have learned those steps (through trial and error), they're there for good, and you may have permanently caught the DIY bug.  I know I did.  By the time I was nearing the completion of the Dayton III, I was already contemplating what I could build this summer (maybe some full-range floorstanders).  For now, however, the mission is complete, and the results are very, very impressive!