[Neruda]

yup, they're all done. They're six feet tall, built with particle board, glue, sweat and blood, and a coupla radioshack 1354's. Here's what they should look like:

beautiful...a nice veneer, shiny varnish, no blemishes at all. oh, um, what? what do mine look like? well, they're ugly, uneven, flaking, dirty, and I think one is leaning a bit to the left. but otherwise they look great!

As far as equipment goes, it's sorta sad. I used some cheapo wire to hook them up to an old sony minisystem. Still, it works. I noticed that they have a hump in the midbass, so I turned the bass tone control on the sony down a bit. (From flat; I din't have the bass up!) This evens up that hump very nicely. Other than that, I can't really tell how nasty the frequency response is. All I can say is that right now the bass seems to drop off around 40Hz and the treble probably drops off at about 12kHz, unless the enclosure was somehow able to improve the treble as well.

And the sound? not bad, suprisingly! At least not for a set of speakers that cost $40 to build. I'm sure they need more burn-in time (the guy who came up with the design I used said that it'll take weeks for them to sounds good), but right now the sound is very agreeable. I had to stuff them quite a bit to bring the mids down; without any stuffing they were horribly hony sounding. I ended up using about half a pound of poly-fil in each speaker, along with a piece of wool felt directly behind the driver. This made the sound much cleaner. I also have them placed about 2 feet from the rear wall for breathing space. The sound is pretty good...I needed to boost the treble a bit before it was to my liking (my friends are going to laugh at me, i've got the treble boosted and the bass turned down

) but I really enjoy listening to them now. For the first time in my life I hear a real speaker soundstage: it's certainly not perfect, but I can start to tell where the musicians are. If I close my eyes I can imagine that the singer is there in the room, and that the drummer is behind him, and that the bass player is to the right. not pinpoint by any means, but it's there. I'm really enjoying that. The bass is good, although I have a feeling it will improve. Like I said, it seems to go as deep as 40Hz, but anything below that is inaudible (you can't feel it either). I don't necessarily want much more bass, but I think I would like it if I had more. I want more deep bass, but not so much midbass. Perhaps the midbass problem will also improve with time. I've been listening to a lot of music through them and they seem to sound good with just about everything. I sorta wish they were more efficient, but I doubt I'll ever be playing these with a 3 watt "pure class A" amp or anything

. Where do I go next with these? Two things: I want to try a few more drivers (I've been looking at this cheap little JBL), and I also want to make them look a tiny bit nicer. I'd love to add a nice veneer, but I probably won't be able to do that. I still have no idea where else to go with their looks. It probably doesn't matter.

I do think that these are fun little speakers, and should prove to be great conversation starters. They were certainly a bitch to built though, as neither me or my dad are skilled carpenters. I think my next project will be a bit smaller. Say, a nice compact fullrange bookshelf for my room.

 

[artmusic247]

Alright Neruda! Sounds like the cabinet works and it's just a matter of finding the right speaker. By the way, what size speaker did you use? As far as the frequency range goes, I could live with 40Hz but 12kHz on the high end seems a little lacking. Do you think if you used like a coaxial car speaker it would extend the frequency range or would it defeat the purpose of this cabinet design? Just wondering. Eh, how about some pics?

 

[skippy]

nice work neruda, now all you need is a digital camera. have you run test tones yet?

i think he has the well regarded rat shack 40-1354's in there.

i have the same ones in my voigt pipe, and the results are not good. the pipe design uncomfortably amplifies the region from the midbass to the lower midrange giving everything a muddy and honky sound. and not to mention the comb filter effect makes the response very peaky throughout the enitre range (which has no extension on either end). yuck... i'm going to go build some hawaii 5.0's for these extra 1354's i bought.

 

[Neruda]

no chance for pics, as I have no digital camera, have no money (or desire) to buy one at the moment, and don't know any friends who have one

. Skippy is right, I have the 1354's in there which are 5 1/4" dual cone speakers. Right now I have no problem with the treble, and will ertainly not be replacing the driver with a coaxial car speaker. The purpose of a full range driver is to not have to cut the frequency range up and have seperate speakers producing it (which is one reason why I would actually prefer not to have the wizzer cone). If I do add drivers, they're only going to be crossed at the extreme low and extreme high end (tweeter would be crossed at about 10 kHz, sub would be crossed at about 50Hz). Then they're just helper drivers with the wideband driver doing most of the work. I would imagine that the average coaxial car speaker is crossed as low as 2kHz, which I don't like at all. So yes, it would totally defeat the purpose of the design.

Besides, you'd be suprised how litte treble extension you really need. Looking that the headroom frequency response graphs, it seems my K401 drops off in the same place (along with a lot of headphones).

 

[JMT]

Alright Neruda, congratulations!

Keep us posted on how they sound after you've had a chance to break them in a bit. Hell, after that, your headphone amp should be a breeze.

 

[chych]

Why don't you try hooking it up to a better amp? I'm sure some friends of yours have decent audio setups or at least a decent reciever, no?

 

[Neruda]

JMT: ha! Compared to amps, this was a friggin' breeze! And a lot cheaper, too!

Chych: sadly, I'm the only audiophile I know. all my friends have cheap receivers hooked up to bose speakers or some crap.

 

[skippy]

a cheap receiver might be better than a sony minisystem. i was using an aiwa minisystem as an amp for testing and measuring my voigt pipe, but the aiwa messed everything up.

crappy digital cameras are getting very cheap (sometimes free). get a cheap one and post pics.

and believe me, the cmoy headphone amp is a hellova lot easier to build than a voigt pipe.

 

[Neruda]

The only problem with testing it out on other people's equipment is that I have to transport these damn things somewhere else and that's really hard. I sorta doubt they'd let me borrow their stuff, but I suppose I could ask.

 

[aos]

Different people are skilled in different areas. I cringe at having to put my projects in a box. Usually takes 4-6 months of active everyday use, where you have 110V wires all over the desk,
before I finally take a drill, a file, a sandpaper etc. And I usually make a mess out of it even if it doesn't readily show. Neruda here seems to be handy with woodwork but the soldering iron is iron-heavy for him. But yeah, I'd say building a cmoy from a kit is trivial compared to building a speaker.

 

[Neruda]

maybe I just refuse to learn, I don't know...it all seems so complicated, what with the caps, the pots, the voltage, the wiring, and all that crap. it sucks!

 

[rickcr42]

Hey Neruda , there are other ways to tame the mid/high band of the rat shack speakers-try some thinned out varnish brushed directly on the cone . Use very light coats applied one coat at a time over a period of days.You might also want to try damping the whizzer cone.By adding too much damping material to the inside of the cabinet you could actually decrease the dynamics or "life" of the speaker ,also you would need more watts to drive it.You also want to try room positioning , any hard reflective surfaces near the speaker or your actual listening position can make the end sound harsh,some room damping in those two places can help ,but again -too much can kill the dynamics

plenty of tweaking info at the single driver website

 

[Neruda]

wait a second.

rick, what's going on? you just wrote a par..para...paragraph, man! Why didn't you space out every line? What happened to you?!

what did you do with the rick I know?

Well anyhoo, I may try the varnish if I have to. I am a bit worried about dampening the highs, though. I'll probably wait a few weeks before I start doing any tweaking.

 

[rickcr42]

QUICK !!!

CALL A DOCTOR DAMMIT !!!!!

I don't know what could have come over me , makes me whoozy just thinking about it.

Quick story (yeah right !)-blame my posting style on Tomo.That's right , all his fault.I wrote this really long post about some of my early DIY mshaps and it wandered as I sometimes do (it was the '60s man , not my fault !)> So even though I broke it up into paragraphs they were long and many . So Tomo reads it and says "Great story Rick but I thought I was gonna go blind reading it !"

I go back and read my post a DAMN ! The man was absolutely correct , a very tough read.So since that day I break it up a bit ,OK maybe more than just a bit ! But hey ,What .

Sooooo=

Back to normal I go.I have been pretty much absent online for about a week so until today did not notice you and some of the gang posting over at the single driver website.But if you do a search on Damar Varnish and also whizzer cone you may turn up some goodies.I think some have also experimented with zoebel networks and such.

**** ,at the cost of the project you really got nuthin' to lose man.Maybe you have found your DIY calling,we won't discuss butterknives or pocket amps !

Rickamundo

 

[Neruda]

hey, did you hear about that bit too? I fixed my grados! And it involved the butterknife again! (seriously)

And I suppose I could try the varnish. If I do ruin a driver it's no biggie; I have five others.

I just hope it doesn't mute the highs too much, since I only want the midrange reduced. I've also decided to buy one of those JBL speakers to test out, maybe they'll work well. I've got plans for all sorts of other speakers, but don't intend to do anything yet. One reason is that I'm not sure exactly what I want to try, and the other is that I don't want to spend any more money on this right now

. Man I use that excuse a lot, don't I?

I'm very interested in this one Fostex speaker, a big 8" with no wizzer. I was originally thinking that it would work well in a bass reflex along with a ribbon tweeter or something, but apparently it tests poorly as far as how deep the bass would go. the Qts is .16 and the Fs is 38Hz, so it seems as if it should work well (despite the fact that the bass rolls off at about 150Hz)...maybe it would work in a TQWT. Or I could buy one (later) and try out a few enclosures until I find one that works. Who knows?