sjm1580
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Wanting to build a pair of top quality bookshelf speakers - Help!
Brian in Oregon
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Unfortunately, there is little interest in DIY at this site. The Parts Express Tech Talk forum is a much better place for such inquiries, as that is where the knowledgeable DIYers hang out and noobs can ask for advice without getting flamed. Really a friendly and civil place.

There are plenty of wonderful speaker kits out there, and the fact that you are a cabinet maker increases your options tremendously, since many of them do not include boxes. The three best sources of professionally designed kit speakers are Parts Express, Madisound, and Meniscus. Smaller companies with nice offerings include GR Research and Zalytron, among others. Available models range from tiny mini-monitors to immense floorstanders, with everything in between.

Important factors to guide your decision will include the size and acoustic properties of your listening room, your favorite styles of music, how loud you like to play it, and what amplification you will be using (highly efficient speakers thrive on low-wattage tubes, but most models out there need the extra juice provided by robust solid state).

So, I'd say explore what's available from the sources listed above, and ask the experts at Tech Talk for advice on which best serve your needs.

CaptainVinyl1
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I have purchased from Parts Express several times over the years for various DIY speaker projects. One can also try Madisound for different brand names. My first suggestion is to obtain a cooy of Vance Dickason's Loudspeaker Design Cookbook, and David Weems' Designing, Building, and Testing Loudspeakers. Weems' book is older but will still have good information and Dickason's really gets into the theory and mathematics of speaker design.
My first real DIY project was my subwoofer. I used the 15" Dayton Titanic Mk III driver in a sealed 6000 cubic inch box of double thickness 3/4" plywood for a 1.5" wall thickness. It is solid and heavy and matches my book shelves/ entertainment center that goes wall to wall in my family room. Originally it was powered by the 1000 watt subwoofer plate amp also sold by Parts Express. Unfortunately the Chinese made amp blew out twice, the second time being out of warranty, so it is no longer used. It is now powered by an older Yamaha 60 watt receiver. I always had used the LFE Out jack on my AV Receiver to the Sub, but now I Use the Harrison Labs 100hz in-line low pass filter between the VCR Out and the subwoofer. I set the 60 watt Yamaha to the sub at full volume, then adjust the bass level to get the desired bass output. I do not have the deepest, most gut wrenching bass, but I do have the clearest , most musically enjoyable bass I have ever had. I find myself enjoying music that previously I had not liked, because now the bass players talents are more on display.

My next project was to build some small but reasonably high quality bookshelf speakers. I used the Morel MW142 midwoofers (2 per speaker) and the Morel MDT 37 tweeter. Using the Loudspeaker Cookbook, i came up with sealed enclosures if 625 cubic inches. These were limited in bass to about 80 hz, but they were intended to be used with the aforementioned subwoofer. Both the sub and these bookshelf units can be seen in the DIY galleries of Stereophile

When the sub amp crapped out for the second time, i built new boxes for the Morels using a vented enclosure of 1425 cubic inches and two 1" ports. Amazingly, with a little help from the graphic equalizer on the bottom two octaves, the ported boxes could get down to about 35 hz in my room. These Morels were the finest sounding speakers I ever owned, though my previous experience was limited to the BIC Model 6 that i inherited from my brother, then my own Polk Audio Monitor 4a and the the Polk Monitor 5.

Recently though, I became interested in flat panel speakers after hearing a friend's big Martin Logan electrostatics. But Martin Logans and even the smaller Magnepans were out if my price range, so i perused the web for possible DIY projects. I quickly found myself in the Parts Express Project Galleries, where I learned of the world of DML. Distributed Mode Loudspeakers consist of basically two parts: A lightweight but stiff panel and an "Exciter". I first saw exciters advertized decades ago as something you could screw into your wall or floor and then your wall would make sound. It seemed Lo-Fi at best. But in the Project Gallery, there was an attractive looking panel speaker that the builder raved about. I saw similar raves in other forums and sites and they all basically indicated that DML speakers offer great clarity, low distirtion, high efficiency, and have a presence that makes it seem like the band is in the room. So I thought it was worth the minimal expense to try it out.

$20 bought me a 4'x8' panel of the pink styrofoam insulation you can get at Home Depot. I went with the 1.5" thick thinking it would be straighter and stiffer than the 1". I made my panels 16" by 48" before final trimming ( roughly the size if the Magnepan MMG). The only preparation needed other than cutting to the desired size us to first sand off the shiny coating on both sides of the sheet, and then apply two coats if a mixture if 1/2 water and 1/2 wood glue (ir even plain Elmers Glue), Since these were going in my family room, the basic pink panels would have had a LOW wife acceptance factor. So i rolled on some light gray paint.
From Parts Express came four exciters at about $9 each. The eciter is basically just a magnet and voice coil with no speaker cone. The front of the voicecoil has a round flange with done strong double sided tape on it. You simply peel off the tape backing and stick it to the back if you panel, about 2/5 of the way up and 2/5 of the way from the edge. My total expense was $80 for the 4x8 sheet, the four exciters, a 50' roll of speaker wire, some banana plugs, and crimp connectors. I made teo sets for me and my son so the per speaker cost was $20.

But how do they sound? Let us just say that the hype I read about was 100% dead on. I was frankly stunned the first time I listened to familiar recordings. Exceptional clarity. At least 6 or 7 decibels more efficient. Tremendous soundstage. In fact, I can literally sit ANYWHERE in the room, and as long as I aim my head directly between the two panels, hear perfect left and right channels. It is said that large panels are needed to get any bass, and mine will barely get to 100 hz, but the sub as set up coirdinates perfectly, and I have rich, fulfilling sound. I find myself listening to the radio much more than before, because even over the radio i am hearing songs in effect firvthe first time.

The DML panels sound do good that the Morels I raved about now go unused, destined to be my surround speakers once I work up the enthusiasm to move them.

I hope my ling spiel was helpful and not just TMI

CaptainVinyl1
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Brian in Oregon
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Well, I would NOT recommend Dickason's "Cookbook" for entry level hobbyists. It's got TONS of math -- all textbook theory -- but doesn't explain very well where and why you would use certain formulae, particularly in the chapter about crossovers. For instance: details the function and calculation of shelving filters, but makes hardly any mention of baffle step and why/how such filters will counter it. Also overlooks the fact that ACOUSTIC crossover functions, which are what you should be targeting, are a combination of the electrical transfer functions of the filters and the unfiltered acoustic responses in the box. More liable to confuse than enlighten the beginner.

Weems kinda the opposite: TOO basic, and originally written for Radio Shack, so all the projects use NLA RatShack drivers.

Roy Alden's "Loudspeaker Design 201" is a much better introduction to the basic theory, in a clear and logical chapter-by-chapter progression.

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