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Forming the Plan

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Ok, so in my last post I talked about how hard it was for me to lock in on a speaker that would sound good. Eventually though, I found at least a basic, well-tested framework of what makes speakers sound good. Hooray! Armed with this information, I felt confident that I could get a good value for my money and not fall prey to marketing hype or personal opinions. Plus, I could probably save enough money to buy a couple solid silver USB cables! :)

So my approach relied on getting specific acoustical measurements on each speaker. Turns out that manufacturers don’t actually publish detailed data on this. It’s just too much information for the average buyer to take in and most likely they don’t want to make people second guess their carefully crafted marketing message. Some speaker review sites publish this data but then you’re at the mercy of what speakers they want to review.

Instead of scrounging for data on mass produced speakers though, I ended up turning to a do-it-yourself design. A guy by the name of John Krutke had been testing and designing speakers for decades as a hobbyist. One of the designs he had come up with caught my eye, as it touted to be “a couple of the best performing speakers at any price” and he had the measurement data to back that up.

The little lines are the frequency response at different angles, varying from dead-on to 60 degrees off center. I’ve never seen a plot that has looked this good.

So it’s called the Zaph ZRT and it had glowing reviews from other people on the net. Reading those good comments helped, even with my confidence in the research study I talked about last post. The DIY guys like to get maximum value for their money and so if the ZRT wasn’t any good, they wouldn’t be afraid to critique heavily.

One problem with going this direction is that I’d have to go in blind (or should I say deaf?). I’d be paying for them without hearing them. That’s completely opposite from the way most people recommend buying speakers and it was putting my faith in the research study to the test. Should I throw all that conventional wisdom out the window and bank on what these guys at Harman said? Was I ready to put down all that money, simply based on the measurement data? There wasn’t any turning back once I got the kit and assembled it– no returns, refunds or exchanges. I could try reselling but I’d lose over half the money I put into it, not to mention all the time I’d spent building it. If this didn’t turn out, I would be back at square one and need to take an entirely different approach.

Maybe it was more the engineer in me than the music lover that decided to take risk. If the principles are solid, there’s no reason for an engineer to doubt the results of his project. Somehow those skyscrapers do hold up in real life, like they do on paper. While the laws of acoustic perception are still much fuzzier than laws of physics, I decided the Harman research and measurement data from the ZRT was solid enough to commit to. Late one night, I pulled the trigger and bought the kit. Now it was real and the project had begun.

While I was waiting for the kit to come in, I started planning the woodworking details. See the kit just came with the electrical components necessary to build the speakers– the boxes (cabinets) these parts go into was up to me to procure. The cabinet plans were all drawn up, but I had never done any serious woodworking so I started by looking at pre-made cabinets. I wasn’t really happy with the looks though and started reading stories of how other’s built their ZRT cabinets. Essentially it was just a long box with some holes cut into it, but to me the biggest challenge appeared to be getting the pieces cut exactly the right dimensions. Anything off and you’d get an ugly and perhaps under-performing speaker cabinet.

So I established a test project for myself — building a subwoofer. Subwoofers are the black square boxes that play really low notes. And they’re the lovely things that wake up the neighborhood at 2am when some punk drives by. Building a sub wasn’t nearly the time or resource commitment required to build the speaker cabinets and if it turned out a little wonky, that was fine. It’d be hidden in a corner of the room anyway. If it turned out really bad, then I’d fall back on the pre-made cabinets for the ZRTs.

I also had to figure out where to build these things. I had run a table saw in my apartment to build some stairs but that ended up coating everything in a nice layer of sawdust. I’d need much more than a table saw for this project and so finding a real shop was a must. I Google… err Bing’d (Binged?) for wood shop rentals and found IsGoodWoodworks. They are a co-op woodshop that rents out their space and expertise to the public. It seemed a bit spendy ($100/day) but that was the only option and I figured I could get it done in a day (haha!). Plus they offered mentorship so I’d have somebody to help teach me the basics of woodworking.

So I thought I had it all figured out. I had my plans for the shop day all written down and my Home Depot shopping list ready to go. But as I waited for the kit to come in, I started getting bored. Bored of the boxey cabinet design. I’d be living with these things my whole life and I wanted something that would be cool to look at year after year. The commercial speakers look much better than these DIY designs and that started sinking in. Those beautiful B&Ws from that day back in college had set the bar not only for sound but for looks.

What I really wanted was a curved speaker. Curved along the sides and rear, just like the B&W 803. The desire gripped me and took me off the charted course. I searched the net for DIY curved designs and came up with some decent examples. None of them were like the 803s but I figured I could use the techniques. Essentially their method was to build a skeleton with curved shelves along its length and then bend thin sheets of wood on top of that.

Speaker of my dreams, the B&W 803!

Here’s how I planned on getting that sexy 803 curve!

So I updated my plans for a curved cabinet instead of a box (monkey coffins, as they’re sometimes called). Even though they were more complicated, I figured I could still get the parts cut out in a day and then assemble it at home. I was even more excited now that I knew they would both look and sound awesome.

So now that everything was planned out, it seemed like it was just a matter of getting to the shop and cutting out the pieces. Little did I know that these plans would be scrapped almost immediately when I got to the shop, sending me into the unknown. You’ll find out all about that in the next post!

Written by admin

May 25th, 2015 at 3:52 pm

Posted in Speaker Project