Gathering advice for build: What's the best DIY speakers you've heard?

I've been on the search for some time now, here and over at the Parts Express forums, for a set of main DIY speakers for the home theater. I'm trying to stay true to my word when I said I wanted to build a home theater based on designs suggested by people here. I'm soliciting your help by asking you guys what you think are the best DIY speakers you guys have personally heard?

I know, when inquiring about people's opinions on commercial gear, the topic of SQ being very subjective is brought up every time and how people really need to get some seat time in and listen to different speakers for themselves. It's one thing to go demo commercial gear when plenty of stores carry them, but it's hard to demo DIY gear because so few people do it. I do not have the most trained ear in the world but I'd like to future proof myself the best I can in case my ear does get much better. The extent of my listening experience consists of a system running Behringer 2030p's with two Dayton 120's, an older version of the Paradigm Studio 100's, the stuff sold at Best Buy and Ultimate Electronics, and just recently a trip up to Audio Dimensions yielded a demo of the B&W 802D's and 805's. I don't have high of hopes of obtaining SQ that could match the B&W's but if you guys think a DIY design gets close, I'd like to hear about it. I think I'll have to exclude line arrays or crazy horn designs, but other than that, I don't think I'm too constrained.

The room they're going in is on the bigger side but eventually they'll have a room all to the themselves so I wouldn't want the room size to be that much of a factor. The wife unit has given the green light on a decent budget of around $600 budget, not including enclosures, however, if I had to throw some extra money at it (I'm easily convinced), I could make it happen. It might cost me a diamond or a pearl , but it's definitely possible.

Some designs I've been looking at include:

Jim Holtz and Curt Cambell's "Statements",(which got great reviews at some DIY events and are constantly be referred to when comparing DIY designs)

John Krutke's "ZDT3.5" (most everyone speaks highly overall of Zaph designs)

Matt Phillip's "Millennium III" (very highly thought of by the Parts Express crew)

Dennis Murphy's "MBOW1" and "CAOW1" (highly thought of by Swerd and many others)

Adam McCall's "1.618"

I know Swerd really likes Jim Salk's "Song Towers" and other Salk speakers so hopefully he will have something to say about a comparable design.

I appreciate you guys taking the time to share your advice!

From what I have seen Krutke's designs seem to be the most neutral. If one were to combine his designs with quality cabinet construction (read: a constrained layer type system with sufficient bracing), a reference type monitor could be in the works. Very few DIY designs I have seen take enough steps to truly minimize or negate the effects of cabinet resonance, nor do they counteract vent resonance in many situations (via notch filters in the x-over).

Starting out it is always beneficial to pick a quality tested design and expand horizons from there.

There are other great designs out there as well, but not hearing them, it is tough to make a decision. Look at anyone posting response graphs and look for the lowest amount of deviations. Remember though, graphs are only as good as how the measurement was taken. There are some measurements that are out there that are not taken real well showing better than true response, etc.

For $500-600 in parts for a pair, I know of a new DIY design that Dennis Murphy has been working on recently. It's a 2-way MTM floor standing tower, designed to be similar to the Salk SongTower and HT2-TL.

The new design, while not an exact clone, bears a very strong family resemblance to both the ST and the HT2-TL. The crossover design and driver choices were Dennis Murphy's work. He also designed many of the Salk products including the SongTower and the HT2-TL. Paul Kittinger designed the mass-loaded transmission line (MLTL) for this new speaker, using the same thinking and methods he used for those two very successful Salk models. TLS Guy – because you’re probably reading this, and steam may be emerging from your ears, I'll call Martin King's MLTL cabinet a quarter wave-tuned ported tower cabinet .

It uses two SEAS 6.5" ER18RNX woofers per cabinet ($81.40 each). The cabinet design for them is complete. I heard an early version last winter and I like it a lot. The bass was excellent, clean, and deep sounding. Dennis said useable bass response went to the low 30 Hz range. That original prototype used a buyout version of an expensive ribbon tweeter, the LCY-108, which is no longer available. Dennis said he planned to develop less expensive designs, offering a choice in tweeters. The tweeters he planned to use are:

Fountek NeoCD3.0 ribbon tweeter ($81.80 each)

Dayton RS28F-4 silk dome tweeter ($40 each this month, regularly $48.65 each)

The last time I spoke with him, over a month ago, he had not worked out the crossovers for those tweeters, but said that he still meant to do it. I’ll email him to see what’s new.

My ZD5's designed by John Krutke. They are fabulous!

Swerd- Thank you very much. This sounds extremely interesting as I’ve read a lot of great reviews about the ST’s and if they’re anything similar, I bet they’ll sound amazing. Right in my ideal price range too. Please keep us informed if you hear back from Dennis.

Annunaki- Thanks for the advice. Since this will be my last major build (that’s what I keep telling Erin anyway) I will do my best to make the cabinets really sturdy. I’ll keep to the original internal dimensions and probably add a constrained layer on top of that. As far as extra bracing goes, I think it depends on the design of the speaker. There’s a good thread on that exact subject on a TL design called the Thor. Here’s a link to that thread. If it's a sealed or ported design, I will add some nice bracing.

Johngalt47- Do you have any commercial gear to compare these to?

Here's a link where Swerd goes a little further in depth about some of Dennis Murphy's designs.

Also, here's a link to htguide.com's list of completed DIY designs.

skyline_123 said:

I'm soliciting your help by asking you guys what you think are the best DIY speakers you guys have personally heard?

Click to expand...

William Cowan's Unitys and Terry's Franks. I've heard the latter several times and William's only once but they were extremely impressive, but not in an "impressive" way. I think of them as SAS speakers; do what they need to do well, with efficiency and competent ease and disappear into the background. Terry's are as good, but different, and stonkingly grand fun.