Austin DIY HT Projects - Page 4

Shepler's sources their tube from Sonoco, so it's sonotube. Same applies for tube from "Texas Contractors Supply". These are the only two retailers in town that Sonoco deals with directly.

Did you get strange stringy things when cutting your tube?
http://boxybutgood.com/temp/sonosub/SubDAY1-002.jpg
What did you use to cut it?

Harlan, hang in there - you'll be rewarded with one heck of a value subwoof. I used 24" diameter tube also for my Tempest and it's an imposing size.

Jeff, I think that strange stuff is wax. The tubes have a coating of wax on the inside to waterpfoof them. If you're going to glue batting to the inside, you need to peel that wax off - it's easy.

Oops.. too late. I already glued the batting in place without peeling off the inner layer. 3M Super 77. It seems to be stuck in place pretty well, though. It takes quite a bit of effort to peel it from the tube wall, so I'm not worried.

An update on my project: I have soldered some 12GA speaker wire to my binding post terminals. I suck at soldering. I couldn't get the solder to stick to the test leads I used as solder tabs. I had to really sand the heck out of 'em. I was suprised to find that they were copper under a thin coating of silver/gray metal. I wrapped some (3M brand) electrical tape around one of the terminals just in case wood filler, caulk, or liquid nails was at all conductive. I filled the hole with liquid nails (to about half-depth). I had originally filled it with wood filler, but as it dried I noticed that it was cracking (shrinking). I envisioned the wad of wood filler breaking loose under vibration and rattling around in there. I had to scoop it all out and pick away the dried bits with a dental tool the next day. I'm going to give the liquid nails some more drying time, then spread a thin layer of caulk over it just for good measure. Anyway, either liquid nails is not conductive, or my tape job held up because the multimeter says "infinite ohms". I'm so close now... come on October, you can't get here fast enough.

Side note: does anyone reading this know Mark Hayenga's phone number? I haven't been able to get in touch with him by Email, HTF private message, or ICQ.

Jeff, Mark is notoriously hard to get a hold of. And to think he gives me crap for being a curmudgeon; I'll have him contact you.

Jonathan: Thanks!

[Edit: he dropped me an email. Thanks!]

My DIY apprentice Emjay (age 4) wanted RED speakers. They're almost ready for his critique. There's one picture on the second page of my Geocities web site:
http://www.geocities.com/hankbond1/index
I wish I could just post a couple of pictures instead of having to put them on that site - the resolution is low. The red color is a bit off on the photo - the cabinets are a dark, but real, red.

My sub is finished! Rather than start two threads on two forums, I posted it to the DIY forum.

http://www.hometheaterforum.com/htfo...hreadid=100562

Harlan, sorry to read about your diameter problem. That's very strange, since in the last couple of years of reading about sonosubs, I don't recall a diameter difference of more than 1/8" or 1/4" between marked and actual diameter. Is your tube marked? Did you ask for 24" diameter and they handed you what you have? They may have made a mistake. If you're going to keep it, re-calculate your numbers - you may want to shorten the tube to make up for the larger volume than you thought you had.
Hang in there - it'll be worth your efforts.

Harlan, I'd fill that "gap" with Liquid Nails, let it harden overnight, then drive trim finishing nails throught the tube into that inner plug. Post pics.

Good job Harlan I like your plate amp mounting method. If you'd like a finishing wrap, I've got some unbacked grey carpet material like I used on my Tempest sonosub. You can take a look at it if you're interested.
Welcome to the HT DIY world!

Harlan: Lookin' good! What did you use to wrap it? It looks like it did a good job of smoothing out (but not quite hiding) the spiral seam. I used two layers of ribbing fabric, and my spiral is still very apparent. Perhaps if I wrapped the tube in what you used and THEN put the fabric on...

Now that you've tested it out, what do you think?

Side note: My wife and I watched "Cast Away" yesterday. That DVD has really great audio, and some great bass... especially the plane crash and the huge waves crashing.

Harlan, sounds like you have a room placement problem. You may have your sub positioned such that at your listening position you are in a point of destructive interference in the room. There are some things you can do if you have any flexibility as far where you put the sub. First, pick up your sub and place it it on your listening chair/sofa (yes, I know it sounds odd). Then, while playing test tones, walk around your room with an SPL meter and chart the response of the room. For example, play test tones at 20Hz, 30Hz, 40Hz, etc. and record the SPL for each frequency at different positions in the room. Note that when you're taking the measurements you want to hold the SPL meter at the same height your ears are when seated. Once you have identified the spot in the room where the response is the flatest, move your sub to that spot. Now the flatest response will be at your listening position. If you don't have a test cd and an SPL meter you can do the same thing, albeit not as accurately, just by listening to the built-in white noise calibration tone on your Denon as you walk around the room.

One other simple thing to try is reversing the phase on your sub. The midbass output from your satellites may be causing cancellations with your sub's output.

The moment everyone has been waiting for has arrived...

My movie screen is FINALLY finished and up on the wall!!!

Yes, it finally has happened. Over the Thanksgiving weekend, I drafted my brother into helping me attach wood pieces to the back of the screen to reinforce the seams. Then I mounted the lengthwise-angle-ripped 2x6 pieces - one on the wall, one on the back of the screen. This was not without some mishaps. Note to anyone undertaking this type of project: DO NOT use the crappy zinc "wood screws" they sell at Home Depot. Three of them broke AND stripped as I tried to attach the wood to the MDF. I had to get stronger "deck screws" (forged from a stronger metal) to attach the wood to the screen and wall.

Some quick viewing of scenes from "Tomorrow Never Dies" and "Lord of the Rings" confirmed for me that the screen has boosted my brightness and improved color balance over projecting onto an off-white wall.

But my enjoyment was cut short as my DVD player rolled over and died. Trouble had been brewing the evening before with mysterious audio dropouts listening to CDs. Then today, I got tons of picture breakup and sound dropouts trying to watch "Lord of the Rings." Now the search for a replacement begins. Soon I will have progressive scan and DTS ... and hopefully DVD-Audio/SACD as well...

See the next post for pictures.

Thanks to all who helped me with the design and construction of this project.

As promised, here are the pictures.

The screen up on the wall

New seating for the next movie night

Now I just need to find a good combination DVD/DVD-A/SACD universal player...

Glory be! Colin's screen is UP!! Congratulations on your nice looking screen there, Colin! And, the new seating looks comfy. So, when do we get to try 'em out?

Anyone look outside today? I think I saw a pig fly by on my way to work. (maybe I shouldn't be talking given how long it is taking to get my crt calibrated)

The screen and seating looks great Colin! Can't wait to see it in action.

Pioneer just came out with a universal DVD/SACD/DVD-A, the only one I've seen to date. Or you could move to an HTPC. M-Audio is currently working on DVD-A functionality for their Delta and Revolution sound cards. I'll put my Delta 410's sound quality up against any pre/pro or stand alone dvd player's sound quality.

Dontcha just love a bold challenge? Okay, sportsfans, who will take Jonathan up on the challenge? Anyone?

Jonathan, see you this weekend for my tools. Also, I want to know how your Mirus Audio speakers were received, and how the Alpha LS's currently sound.

Hank -

I am tentatively planning on hosting a movie night on Saturday or Sunday, December 13-14. Scott Oliver may be bringing his Theta processor over for me to audition that weekend.

At the movie night, we could take up Jonathan's challenge (unless it requires 6-channel analog inputs to a preamp).

Jonathan -

The Pioneer combi-players have gotten bad reviews for sound quality and video performance (esp. chroma bug and problems with deinterlacing video-source DVDs). Many of the competing units on the market are based on the same video platform but have improved analog audio electronics.

Someone needs to make a high-quality DVD/SACD combi-player with Sage/Faroudja deinterlacing, an MPEG decoder without the chroma bug, and quality analog electronics. Sadly, this has not been done yet. I cannot comprehend why the chroma bug is still with us. Manufacturers have had more than a year to fix their chipsets, and many have still chosen NOT to. The only thing we can do now is avoid their products until they get the message.

I bought a Panasonic DV-SP82 as a stop-gap measure while I wait for manufacturers to get the high-end combi-players right. Given my Classé processor doesn't have 6.1-channel inputs, I couldn't immediately make use of multi-channel SACD or DVD-Audio. So this $230 player will at least give me DTS (my old player was so antiquated it didn't even have DTS support) and Faroudja/Sage deinterlacing (considered the best progressive-scan chipset in dedicated DVD players right now).

Fight! Fight! Let the games begin!

Radical idea from the middle-aged guy: SEPARATES. Period.
Players have moving mechanical parts (thus are the only gear I'd ever recommend buying extended warranties for). Assuming you listen to CD's more hours than you watch movies, why not buy an optimum CD player and a separate DVD player? I'd venture that they'd both last longer than a do-it-all combi player that also dispenses frozen daquiris.

Hank -

I have trouble with the "separates" idea for CD/SACD and DVD/DVD-Audio. It is an expensive duplication to buy two transports, two sets of analog audio electronics, two power supplies, two chassis, etc. For a given amount of money, I'd rather buy one really good transport, one really good 6-channel analog audio section, one chassis, and whatever else is needed to support all formats in one box.

After all, it seems that a good 6-channel analog output stage has been designed and built already. This should be reusable in any number of products going forward. There are already MPEG decoders without the chroma bug. There are already DACs for DSD (SACD) and PCM (CD/DVD-Audio).

I am not an electrical engineer, so I don't understand all the complexities in getting a product designed, built, and shipped. However, I'd think that these components can benefit from modular design, making a new product with new features just a minor revision away.

It shouldn't take the high-end companies 2-3 years to upgrade their pre/pros, and a quality universal DVD/DVD-A/SACD player already should be out there. So I will wait until these companies get it right...

The Delta can do digital out or analogue out. Using the digital out into the Theta's DACs I don't believe any of us could tell the difference between the HTPC's audio and the standalone player into the Theta. Using the analogue out you could tell a difference, just like at the pre/pro shoot out, and I consider the 410's analogue out to be as good as those pre/pros.

I think we have a challenge and an acceptance. Onward.
Oh yes, I'd like to see a real double-blind pre/pro shootout. Ours was not strictly administered and therefore frought with bias possibilities.

Should we start a new Austin HTF Meet thread to publicize this gathering?

Since there are only two units in this go round it might be possible to do an ABX test. I'll check into it.

Yes, a new thread for the next "official" Austin HT meet. We might need an ancillary subject also. Target date: mid-January sound good?