First DIY Attempt in 15 Years - Project Cheapskate

[Oklahoma Wolf]

I've been holding off on my first post here until I got closer to the end of my project than the beginning, and since I think I'm finally getting to that point I thought I would show you all what you've inspired me to do with my home theater.

First, a little background. Some of you may or may not know me as the resident computer power supply reviewer at jonnyGURU.com. Well, since way before I got started with that I was an audio nut all the way back to childhood. Used to spend hours in the local audio store in the 80's just looking at stuff. As my teens began, I became interested in speaker building. My first design was a modification on the Cerwin-Vega series 2000-15 model, a speaker I particularly liked. At the age of 12, I sent it right off to Cerwin-Vega for Mr. Czerwinski's approval. No response... I was crushed.

But, I kept thinking about speakers. Couldn't stop thinking about them. At 14, I grabbed a speaker design book and drew up another one based on a Radio Shack 15" woofer. Built it in Grade 8 shop class. Looking back it was a terrible design with flimsy wood, but I was only fourteen. Built the companion to it when I was 17. And these would be my home theater speakers for years to come. EQ'd, they sounded decent. Around that time I became an electronics tech and spent some time in pro audio. This experience gave me the desire to come up with something better, but there was a problem - due to mental and physical health issues, I never could earn the money to actually do something better. Other more important things always came up.

But that was then and this is now. I'm no longer in a position of having to put this little obsession aside. So, all summer long I've been upgrading the home theater. That said, I still had a budget - therefore, I call this "Project Cheapskate."

So, here I was with some money saved up and a desire to do a huge home theater overhaul. The money was there for a good subwoofer and receiver, but I would quickly go broke if I did what I wanted with the main speakers. Now, I've been collecting Chrysler/Infinity speakers for years - when I go to salvage yards and can't find parts I need, I always grab a set of those speakers so it's not a wasted trip. Well, all this has resulted in me finding these on the storage room shelf:





Fourteen Chrysler/Infinity 5.25" speakers from first generation minivans. These have EMIT tweeters on them, or I wouldn't have bothered even thinking about them for this project. Advantages to these - the tweeters. They sound amazing. Disadvantages - a not so good woofer with a tiny magnet that relied on onboard booster amps for good sound.

Total cost so far: $35 Canadian. For all fourteen. Hard to argue with that, especially when one isn't expecting the moon from them. Already had some 15mm thick plywood left over from other things, so I decided to use that too. The idea was to go 7.1 channels as cheaply as possible with passable sound quality. To that end, I needed a receiver that could get the most out of these speakers. I chose the Pioneer VSX-919AH... it was the cheapest thing I could find with 9 band EQ'ing on the main channels. All my budget was for receiver and subwoofer... I reasoned I could do the 7 main channels over again next year if I didn't like them. Power was not an issue - these speakers run off 40 watts or so in their intended application. Doesn't take much.

[Oklahoma Wolf]

So, I now had a receiver and a plan of attack. The Chrysler/Infinitys were designed for free air, so I would need the boxes to be fairly big. But at the same time, I had a limited wood supply without getting into the subwoofer fund. So, I decided to drop two C/I's each into boxes 14x12x16.5." They would be wired in series with the onboard amps bypassed so the Pioneer didn't self destruct. I grabbed a set of ten binding posts off eBay, a roll of 14 gauge speaker wire, and a Black and Decker circular saw, and got to work.



Wood cutting took place outside on the patio in some very warm weather.



This pic is at the end of day two. Cutting wood for seven boxes this small is not a small job. Especially if you're like me and have no money for table saws or other tools.



Getting closer to completion - five of seven assembled sans drivers.



My eBay binding posts. They're long enough to go through some seriously thick wood.



Two of them post assembly being tested. That's an old JVC receiver someone gave me for free that had issues (and still does, only not as bad).



Mission accomplished. The plywood is full of voids and the drivers are not what I'd consider ideal for home theater, but for a total cost of like $60 Canadian I am not about to complain. Sound quality is surprisingly good, once MCACC got through with these. The tweeters are still amazing, the woofers not so much.

That said, there are issues. How could there not be at my budget? The first issue is - the woofers. They're out of control. No surprise since the crossovers were in the onboard amps on the back. They scream for a proper passive crossover. MCACC attempted to compensate with a massive cut at 4.5kHz, but that only goes so far. The tweeters are still factory with a resistor and capacitor as their only crossover. The second issue is, the enclosures. They resonate, thanks to all the voids in that plywood. They're also just slightly too small to get any bass out of there. I get useable output to maybe 60-70Hz with MCACC's 60Hz boost - that's it. The plan is to stuff them once I can afford some cheap pillows - will see what that does. Meantime, they're crossed over to the subwoofers at 100Hz. They sound decent that way... just decent. The tweeters don't wake up until somewhere around 4kHz, and there they sound incredible, so the woofers do most of the work.

[Oklahoma Wolf]

How warm does the Pioneer run? Very, very warm. I suspect those 14 EMITs are responsible, series or not. The fan comes on pretty often at times, but usually it cuts off again once the loud parts are over. MCACC originally had these set up with the left and right front set to "large" - I didn't want that, so they're all set to "small" now. That said, the Pioneer actually runs cooler than it did with my old speakers. Probably because it no longer has to do bass through the main channels. My old main speakers with the 15" Rat Shack woofers are now the temporary subs.

But not for long... I started the new subwoofer a month ago when I took delivery of this:



That's an 18" Mach 5 IXL in front of the old Rat Shack 15's. I don't cheap out on subwoofers. Well, not much anyway

I owe NEO Dan some thanks - it is his easy button design mine will be based on. I made a few changes to it as I am not a fan of MDF and went with plywood again, but it's still an easy button build. The bracing will be different (I'm using hardwood 2x2's) and the box volume will be a little bit greater, and the tuning will be a wee bit lower (unless I change my mind again).

So, here's the wood. Baltic birch was too expensive, so I grabbed 11 ply C2 grade shop birch.



It's not totally void free, but it's close enough methinks. I had a hard time finding any voids. This stuff was $35 a sheet on sale from Windsor Plywood. I had to hunch over like Quasimodo in Dad's short wheelbase Caravan to get this home... it came up over the front seats and almost hit the sun visors. And I'm not a short person either.

Cutting of this wood took place on yet another warm day. 33 degrees, last Thursday.



Found a few more voids after this was done, but still nothing major. I love this wood... it's cheap, and not bad looking. My kind of wood.



Sheet one was easy. Zip, zip, zip, and I was done. Three panels. Three huge, heavy panels. This subwoofer is going to need a forklift to move.



All sheets done. The smaller panels are for a planned IXL 12" car sub. I messed up on the dimensions of two of those panels and have to recut from the leftover shop birch, but fortunately the big box's cuts are what they should be, what with me measuring 6 times before making any cuts. It just got too hot that day and I got sloppy on the car sub. Glad I saved it for last... going back for more shop birch for the big box was out of the question where I live.

And so, here I am on a Sunday morning with all panels cut for my easy button IXL. Were it up to me, the box would have been done yesterday, but my brother in law forgot to bring home the bracing - it's going to be a matrix of hardwood beams made from a hacked up 2x4.

[Oklahoma Wolf]

Some of you may be curious about the electronics side of the subwoofer. Well, I do have a background in pro audio, and I still have connections in the industry. One of them is selling me a used QSC RMX-1850HD for a good price. Yes, I could get a Behringer new for the same price, but I gotta be honest - I'm a loyal QSC guy. I'd rather have genuine QSC than a clone. Processing will be a Reckhorn B-2. Amp will be located in another room so I don't have to worry about swapping the fan. I may want to use the amp for live sound one day - I have to leave the fan as is. Wiring back to the sub is already in place using this 10 gauge stuff:



And I think that's it for my story for now. I'll have more when the sub goes together, probably Tuesday. I'm still a good week away from getting the amp, so it's still painfully far away from Xmax Eve for me, but my DTS copy of the Haunting isn't here yet either so I guess I'll live somehow.

There will be no fancy measurements taken of the room, I don't have the gear (or budget) for that, but I do plan on using the pair of old dopey looking microphones on either side of my head to do some fine tuning via a WolfTech 2000 audio processor that has way too many wires crossed and seems to require an endless supply of Coca-Cola to work properly, but it does the job.

I'll have pics of the room with the new main speakers all mounted as soon as I get that room cleaned up. It's about 10' wide, 7.5' high, and 25' deep. The project will conclude with the purchase of a projector and screen, but that part of it is a ways off yet. At any rate, I don't reckon one IXL 18" will have trouble with this room, but just in case it does the amp should have enough kick for a second easy button IXL. Especially if I sell this woofer and go 2 ohm per channel with Mach 5's upcoming new coil options. I chose this amp specifically for its 2 ohm stability. Muahahahaha!

That's it from me for now. More on Tuesday, if the bracing finally shows up. Feel free to laugh at my el cheapo main channel speakers all you want - they're definitely not the best out there, but they're good enough for a while. And I no longer have all that scrap wood lying around, and those speakers aren't just sitting around doing nothing.

Whew - long post.

[KlipschHead281]

Wouldn't MDF make more sense? Resonance would be less of an issue for both the sub and the smaller enclosures. I like the concept over all but for a tad more money those Chrysler speakers can be beaten easily with cheapies from Parts Express.

I'm not a DIY expert by a long shot so if I'm wrong someone correct me.

[Oklahoma Wolf]

There's a tradeoff - MDF isn't as stable as ply. It's also harder to work with, and that's where my health issues come into play. I'm allergic to a lot of things, and I had to keep the dust down. As it is, I still had an allergic reaction to this stuff, even working outside. I picked plywood for the sub because I wanted to cut down on bracing a little bit to get a little more volume so I could tune to 11Hz instead of 11.5Hz... MDF wouldn't have responded well to less bracing. But you're right, it doesn't resonate as easily.

I already had the Chrysler/Infinity gear - the idea was to just get them off the shelf and working. Also, I figured those boxes could do double duty in working off my woodworking rust before I got to the more serious part of it (the sub).

[tundrSQ]

Sorry, but that 5 ply cdx you used on the speaker boxes is not more stable than mdf.

[Oklahoma Wolf]

Originally Posted by tundrSQ

Sorry, but that 5 ply cdx you used on the speaker boxes is not more stable than mdf.

I know. You missed the part where I said I already had it and wanted to get rid of it

I was talking more about the stuff I'm using for the subwoofer. I probably should have phrased it differently.

[Servicetech571]

Looks to me like you would be better off balancing the budget. You have crazy money invested in the bass w/o enough left over for some box stuffing for the mains. The mains look like my high school projects I did bad in the 80's, sounded good for the price What part of Oklahoma are you in?

[Oklahoma Wolf]

lol - yeah I know. I have a few screws missing. I just figured I'd rather use up all the stuff I can't ever seem get rid of and see what happened first. Like I said, I can always go get some Baltic birch and do something better down the line. But I wanted to do something - I was still running Dolby Pro Logic in here up until June.

If I'd had the T/S parameters of those Chrysler/Infinity woofers back when I got started, then I might have sprung for decent wood and then ported them. As it was, I didn't want to use anything expensive for an experiment like this. Good thing too, because these boxes are definitely too small. The sub is another story since it's a good design for a known good woofer.

All that being said, I have to say I'm not displeased with the sound of these things. It's not up to my standards, but it's a whole lot better than what I had. Not sure what that says about the stuff I did 15 years ago, but I'm not unhappy with these given what I paid into them. I'm seriously considering keeping these tweeters for the next build - some of you might be surprised how good they sound for late 1980's premium factory audio. I'd have to spend a little bit to get 7 tweeters I'd like as much.

I'll probably grab some stuffing for the box in Saskatoon next week. Gotta get the sub amp first. That IXL has been sitting there mocking me for four weeks... time to put it to work.

I'm actually not in Oklahoma - I was only born there (Enid). I've been in Canada since 1980. Otherwise, you probably would be hearing about my Mal-X build (budget didn't go far enough to get one over the border). That's actually one big reason I'm after that big QSC - I might want to do something with that 21" later on.

[PassingInterest]

You win my vote for ultra-budget DIY speakers.
Way to go, recycling classic parts and making good use of materials on-hand.
At least you'll have your 7.1 surround sound until you can start on your DIY upgrades some time down the road.
Keep us posted.

[Oklahoma Wolf]

Sure thing. I'd forgotten how much fun this little hobby could be, and now that my interest has been fully re-awakened I'll definitely be doing more. As long as it took to get these seven little boxes built (4 days), it was just as rewarding as I remembered from my teen years.

I've already caught myself drooling over the Shiva-X thinking to myself how great it would be with a plate amp on those days when I just can't seem to un-lazy myself enough to go into the other room and fire up the IXL's amp. That's the one thing I really hate about the Pioneer. No trigger output, or switched outlets. Otherwise, I love it.

Watched Way of the Gun this evening. Not much LFE in that one, but man was it ever using the surrounds at the end. First time I can remember hearing the Pioneer's fan running for more than a couple seconds after the loud stuff was over (and was it ever loud, even at -17dB volume level). Well, first time since it had to do the bass content too. I'll have to throw Twister at the system when the QSC and Reckhorn are here and see what these things can really do.

[Dradius]

very cool project man. of course you could do better if you bought blah blah blah, but you wanted to use what you had, and with that it looks like it turned out pretty well. plus you had fun doing it which to me at least is one of the most important parts of DIY.

[Oklahoma Wolf]

Thanks

I'm all giddy with excitement. The subwoofer goes together today. My BIL messed up two of the braces, so I have to go cut some shims, but that's no big deal.

The Haunting showed up yesterday too. Now, if only my copy of War of the Worlds hadn't gotten stolen I could try that too.

[KlipschHead281]

Originally Posted by Oklahoma Wolf

There's a tradeoff - MDF isn't as stable as ply. It's also harder to work with, and that's where my health issues come into play. I'm allergic to a lot of things, and I had to keep the dust down. As it is, I still had an allergic reaction to this stuff, even working outside. I picked plywood for the sub because I wanted to cut down on bracing a little bit to get a little more volume so I could tune to 11Hz instead of 11.5Hz... MDF wouldn't have responded well to less bracing. But you're right, it doesn't resonate as easily.

I already had the Chrysler/Infinity gear - the idea was to just get them off the shelf and working. Also, I figured those boxes could do double duty in working off my woodworking rust before I got to the more serious part of it (the sub).

I wish you luck, I'm looking forward to more photo's.

[Oklahoma Wolf]

Here's a couple to hold you over:



One more of the IXL 18.2.2.



This is the room I'm dealing with. Excuse the mess. There's exactly one window and it's to the right of where I was standing. It's covered most of the time by foliage or snow depending on the time of year. That's why I want a projector - it's like the room was built for one. Components seen in this shot include the Pioneer 919, Toshiba SD-6100 and Panasonic DVD-S47 DVD players, Starchoice DSR-317 receiver, and my old JVC I'Art 27."

You can see five of the seven speakers mounted in this shot. The surround back speakers were right above my head there. Normal listening position is more or less right between the two side speakers - they're as far back as I can get them without hitting some light fixtures on one side.

Sharp eyes will spot the 10 gauge speaker wire for the sub on the right hanging in front of the temporary subs and their old Noresco (built in the 70's by Harman Kardon) amp. That amp hisses like crazy, but it's worked ever since I brought it home in 1987 with a Dual turntable on top for the grand sum of $5. Rated at 120W total at 8 ohms, and I believe it.

The 10 gauge runs through the ceiling and into the room behind where I was standing - the lab for all my jonnyGURU.com review sample testing. The QSC will run off the same 20A circuit I use for that work since that circuit sits there and does nothing most of the time.

[Pure-Evil]

well, that looks like fun, GHETTO, but fun. i hope you change your mind and build the sub outta MDF instead. you will certainly regret it if you don't

[Oklahoma Wolf]

Originally Posted by Pure-Evil

i hope you change your mind and build the sub outta MDF instead.

I won't, unless you're offering to buy and cut the wood for me. Already have the birch ply, and no willingness to deal with MDF dust. I'd have to drive two hours to get the stuff anyway.

I doubt I'll regret it. I'll find out on amp day next week when I'm able to get that IXL moving.

[penngray]

i hope you change your mind and build the sub outta MDF instead. you will certainly regret it if you don't

Why? Some of the best subs built are BB ply.

[maxcooper]

Congrats on your project and thanks for sharing.

For free stuffing, how about finding some old couch pillows?

-Max

[Oklahoma Wolf]

I don't have any old couch pillows - I think I'll just run to Rona and get some fibreglass (unless you guys have any other suggestions).

I'm half done - taking a break. Three panels on: bottom, side and top. Sonotube port is in place. Things I learned so far - hardwood 2x2's can drain a drill battery fast and snap drill bits even faster if you're not watching what you're doing. Also, I may not have enough glue.

[maxcooper]

I see a lot of them on the side of the highway.

-Max

[tsloms]

This is a great build thread.

It's a down and dirty, back to basics build. It's all about the enjoyment from building your own speakers. They don't have to be mega $$ in order to get enjoyment from them. I wish you the best on your sub build.

Stick with the ply. It will be a bit lighter and easier to move around and give more rigidity than MDF.

[Oklahoma Wolf]

It is done. I now have a casket next to the TV set. Started at 2pm and ran the last screw into the woofer basket around 7:30pm. I would have gotten it done sooner had the drill battery not croaked... three times.



Port mounted. I messed up on the cut for that... you can probably tell. It's probably not tuned to 11Hz anymore but slightly higher. Three panels screwy and gluey. Half the bracing installed with the long braces test fitted to see if they'd work. Fun fact - screwing together 2x2 hardwood bracing with 3" long screws is a massive pain. I actually couldn't open my hands back up after a couple of these. I'm going to look like Popeye in a week, what with that and the sawdust in my eye. Didn't help that the drill battery was charging (again) at the time. The bracing holds the port in place.



From the other side showing my ghettotastic job on the port hole. Santa needs to send me a router for Christmas. I am not doing this again without one. Period. No, wait... exclamation point, exclamation point, exclamation point.



Getting closer. All bracing in place, four of six panels gluey and screwy. You can see the shims I made from leftover CDX on the two vertical ones in the foreground. Those two got 2.5" long #10 screws whereas everything else but the braces got 1.5" #10's.



Binding posts in. 12 gauge wire installed with 1/4" Gardner-Bender screw clamps. Stupid me, I made the positive wire almost too short. Almost.



All done at last. Sun's going down so I better get the driver cutout done but quick. Oh, look - the drill battery is charging for the bajillionth time.



What do you do when you have only a jigsaw and no router? Well, I did this. Before I drew on the box, I drew on some cardboard as a test and then cut out the resulting circle. To be sure it wasn't off, I dropped my cardboard circle on the IXL. Perfect. The driver fits like a glove.



See? Test fit was perfect. You can't wiggle the driver back and forth, it's that cozy.



Good God, what have I done? Final dimensions are 25.5" x 25.5" x 49.5." If you look real close, you can see the Noresco is turned on. Yes, I was testing the finished product with a 60W amp (well, more like 120W since this is a 4 ohm load). It works, but naturally the Noresco can't move the IXL too much. I had to watch that it didn't clip, but it did better than I expected it to. Three cheers for Harman-Kardon

And now for some good/bad news. You know those enclosure resonances I spoke of on my 7 channel mains? Well, I found out it's not resonance. That's the good news. The bad news is, at least two of the 14 drivers have loose tinsel leads to the tweeter. They're loose where they go through the woofer cone. Not an uncommon problem on these old Chrysler/Infinitys. Grrrrr. I hate fixing that. Time to go get some glue.

So, how does all this sound? The IXL is magnificent, as expected, even on that little amp. I am now kicking myself though... I never tried my 7 channel mains in stereo mode with some simple CDs. I was missing out big time. At first, I thought the center channel was still on, the imaging was that good. Sound quality was incredible, especially with that monster handling the low end.

I'm going to fix those loose tinsel leads and run these speakers for a long time to come, I think. They don't sound nearly as cheap as they look. I'm still going to stuff the boxes, but that's probably it for a good long while.

Happy, I is. Now to go buy me an amp that can really wake up the IXL

[tundrSQ]

awesome sub....looks a little small though

BTW..i built one out of Birch ply about that size and then i built one out of MDF...Birch ply sounds just as good...weighs about a 1/3 of MDF and did not cause me to cough up brown sludge for 2 days

[Oklahoma Wolf]

Heh - I fully expect to build a sub one of these days big enough to serve as my coffin later on down the line. I'm 6' 5" and change, so that might be a good size one. My funeral will accordingly have several selections of bass testing tracks

I can't imagine I'd have been able to get this down the stairs alone had it been MDF. As it is it probably weighs a good 130-140 lbs without the driver. I can just get it off the ground one handed with it lying flat by reaching in and grabbing one of the long braces. With the woofer in place, I had to resort to pushing and dragging it around.

Didn't get very low with it last night, and it may not be possible with that amp, but I might give the recordings at www.acchos.org a try today. The world's largest pipe organ should help with that. Some of those tracks have content at 8Hz (this is one of only two organs worldwide with a true 64' stop), or so I'm told. I'd try the new space shuttle one, but that one sounds like it'll be an exercise in Noresco clipping. I want to take it easy on it. I did try lots of music from BT, Yanni, Chicane, Snow, and Blank & Jones to name a few and some of those recordings had content I'd never heard before. It's going to be fun when that QSC gets here.

Sold the old temporary subwoofers. Need to get them to their new home so I can move the beast forward. It's blocking an outlet there. Wish I could stand it on end below the right channel main - there's room, but the IXL's magnet interferes with the JVC there.

[Dradius]

wow, you've been busy. Nice job on the sub!

[Th3_uN1Qu3]

Nice to see you here as well. You do a great job on EOCF btw. And that's some nice ghetto work there - i'm the ghetto guy as well, since the lack of $$$ means i have to cheap on a lot of stuff. But at scrap heaps in my country... i'd be lucky to find half a speaker.

I have some projects coming soon, but i need some time, which i don't really have atm. I was planning a pair of fullranges with four cheap 4-inch drivers each, and a 10" sub to go with them (i'm really short on space in my room). It'll hopefully come soon.

PS. Measuring T/S parameters with reasonable accuracy is doable with a multimeter that has a 2v AC scale, a tone generator (your computer), a market scale (which you can borrow), and a few small weights. Need any details, i can explain.

[Oklahoma Wolf]

Thanks guys

So, I tried the recording of the Atlantic City Boardwalk Hall organ. Some from the website, some from the actual CD.

One track in particular is a demo of that 64' stop that slowly moves down the notes until it hits low CCCCC, at 8Hz. Even at less than 120W input, this bad boy played every last note. On a very much related note, I need to secure some wall paneling. On the other side of the house.

[Fatawan]

Originally Posted by Oklahoma Wolf

First, a little background. Some of you may or may not know me as the resident computer power supply reviewer at jonnyGURU.com.

I thought I recognized that name from somewhere! Welcome. jonnyGURU is always my first stop when building a new PC(Antec Signature FTW in my latest!). Way to go on your latest audio upgrade. The QSC amp will bring that sub into a whole 'nother dimension!