WOW!
I've got about 20 hours on them now. Bass is definitely heavy w/o the bsc. With it the bass becomes rather remarkably airy and transparent. The hollowness of a kick drum is really conveyed, same for a bass fiddle.
The little paper woofers (very glad I went with the paper ones) can produce enough high freq. Despite my initial concerns. I do feel the bsc is overattentuating though, I'm going to try and get to the shop to buy some more resistors so I can play with that...
I've got about 20 hours on them now. Bass is definitely heavy w/o the bsc. With it the bass becomes rather remarkably airy and transparent. The hollowness of a kick drum is really conveyed, same for a bass fiddle.
The little paper woofers (very glad I went with the paper ones) can produce enough high freq. Despite my initial concerns. I do feel the bsc is overattentuating though, I'm going to try and get to the shop to buy some more resistors so I can play with that...
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These look like a good option for a fist build, but i'm concerned with them not being able to play loud enough. Ray, how have these performed SPL wise? i know you were concerned with maximum volume too.
and/or is there anyway to incorporate another driver into each? i was thinking about using the 4" ones, but if i could drop in 2 3" or even 2 4", then it seems that reaching sufficient SPL levels wouldn't put too much stress on the drivers.
and/or is there anyway to incorporate another driver into each? i was thinking about using the 4" ones, but if i could drop in 2 3" or even 2 4", then it seems that reaching sufficient SPL levels wouldn't put too much stress on the drivers.
Heh, pit there's no caps in my bsc!? No caps in the whole speaker!
My bsc's consist of two solen air cores and two flameproof resistors dangling off the bums of my tabaq's!
SState13:
Seriously great speaker for a first build. And if you do I strongly recommend using the 3" paper coned ones like I did. Paper always sounds good
And I really really doubt the 4" woofers will deliver the necessary sparkle in the highs. Also highly recommend adding the extra compartment on the bottom for added head and mass loading. makes them very stable.
SPL? I'm running them on the audiosector.com LM3875 with a passive pre-amp. So the only gain is what the amp itself makes. For full-on Star Wars watching I have the pre at about 85% throttle. And they are very loud in my medium sized space. Never actually driven them to distort so I can't say just how loud they go. But with a real pre on my chipamp I'm confident it could be deafening.
My bsc's consist of two solen air cores and two flameproof resistors dangling off the bums of my tabaq's!
SState13:
Seriously great speaker for a first build. And if you do I strongly recommend using the 3" paper coned ones like I did. Paper always sounds good
And I really really doubt the 4" woofers will deliver the necessary sparkle in the highs. Also highly recommend adding the extra compartment on the bottom for added head and mass loading. makes them very stable.SPL? I'm running them on the audiosector.com LM3875 with a passive pre-amp. So the only gain is what the amp itself makes. For full-on Star Wars watching I have the pre at about 85% throttle. And they are very loud in my medium sized space. Never actually driven them to distort so I can't say just how loud they go. But with a real pre on my chipamp I'm confident it could be deafening.
You need SPL from hell when your boxes, your music or your ears are crap. Our hearing judges by the amount of info coming in - high compression mp3 via earbuds or a $59.99 5.1 jobbie make you turn the wick up. Come a few years, the mp3 generation will rent flats of their own, and their hearing will be battered zilch by then. I´ll take my turntable and my fullrange boxes and move elsewhere.
I wouldn't worry about SPL on these with anything other than a low power valve amp. You will hit the limits of the speakers cones faster than the limit of the amp with almost anything solid state. If you want earth shaking power a single 3" driver is not going to deliver no matter what anyway.
I used the 4" and it does lack the better high end of the 3". A trade off for the bigger low end I guess, and you can't have it all in a $30 driver. I have actually ended up with rear-firing tweeters on mine just because I had them spare, which seems to work well to improve the upper end without although the circuit behind this is more trial and error than science.
I used the 4" and it does lack the better high end of the 3". A trade off for the bigger low end I guess, and you can't have it all in a $30 driver. I have actually ended up with rear-firing tweeters on mine just because I had them spare, which seems to work well to improve the upper end without although the circuit behind this is more trial and error than science.
Ok, thanks for the answers, i was really considering abandoning the single driver approach, but the star wars comment is all i needed to hear. The only reason I was going to go with the 4 inchers was to gain as much overall volume as possible. But I will be using a subwoofer, so the really low end won't be a problem as long as they reach down through 80Hz or so. I've never used, or even heard single driver setups, so i guess i really didn't know what they are capable of. Power will not be a problem, I have 80 watts at 4 ohms to play with, driven by a real preamp. I was much more worried about the speaker being able to take the power.
hopefully I will be able to start on some of these soon... and the BSC circuit ur using, is it just the one recommended in the pdf of the plans?
hopefully I will be able to start on some of these soon... and the BSC circuit ur using, is it just the one recommended in the pdf of the plans?
For adjusting the bsc, use a binding post plate with a weatherseal foam gasket, mount the bsc to that, it'll glue on nicely with rtv or silicone. Then just pull the plate out if you need to get at the bsc.
For adjusting the batting....
Here's what I'd do.
(Assuming 3/4" material)
Build a 3/4" lip around the inside rear of the cabs, recess it about 7/8ths" from flush with the back. Then assemble the whole cab spare the rear baffle. You should then have a hole in the back of your cabs (obviously) with a lip all around it set back slightly more than the thickness of your material. So long as you were clever enough to put tee nuts on the lip at the beginning of all this you'll then have receivers for machine screws. Run a band of one-side adhesive weather seal around the lip and then screw on your nifty removable baffle.
Maybe I should sketchup this?
nah, u don't need to do a sketchup, i totally understand what you are saying. Thats a good idea with the binding post plate, i was planning on using one anyway, i guess i just didn't realize how small the components for the BSC are.
So i take it you didn't make a removable panel. if the stuffing is easy enough to get right on the first try, then i would rather not put in all the extra effort (and add more things that can go wrong)
So i take it you didn't make a removable panel. if the stuffing is easy enough to get right on the first try, then i would rather not put in all the extra effort (and add more things that can go wrong)
Yeah, here's the procedure for weighing the batting...
You need 100 grams of the stuff.
You can either do the coin trick: (Canadian pennies of the last 40 years weigh in at an average of 2.33 grams pretty darn accurately)
Or you can get a digital scale and a mason's jar, or anything you can stuff the batting in. (for some reason it weighs more when it's jammed into something, I think it sorta floats when it's all loose).
1. Weigh your mason's jar or whatever.
2. Jam batting in it.
3. Weigh the batting and jar subtracting jar weight.
4. Play with it till you've got 100 grams.
The penny trick is tedious, I suggest 'renting' a scale from wal-mart if you don't have one in the house.
oh I think U.S. pennies avg. about 2.6 grams...
You need 100 grams of the stuff.
You can either do the coin trick: (Canadian pennies of the last 40 years weigh in at an average of 2.33 grams pretty darn accurately)
Or you can get a digital scale and a mason's jar, or anything you can stuff the batting in. (for some reason it weighs more when it's jammed into something, I think it sorta floats when it's all loose).
1. Weigh your mason's jar or whatever.
2. Jam batting in it.
3. Weigh the batting and jar subtracting jar weight.
4. Play with it till you've got 100 grams.
The penny trick is tedious, I suggest 'renting' a scale from wal-mart if you don't have one in the house.
oh I think U.S. pennies avg. about 2.6 grams...
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I went with overstuffing, then picking out the excess through the driver cutout as required. I thought it would be easier to do this then to have to put stuffing evenly back in as I didn't have a removeable baffle.
I was less scientific with the weight of the stuffing: the bag of teddy bear filler I bought had a weight of 250g marked... so I cut it evenly in half and removed a little bit before use.
I was less scientific with the weight of the stuffing: the bag of teddy bear filler I bought had a weight of 250g marked... so I cut it evenly in half and removed a little bit before use.
I have about 160g per in mine. I was shrewd enough to put the back on with brads for the first week, I started at precisely 100, then to 120, then 40 more to 160.
It's a taste thing really, I feel it sounds tight with more stuffing. But there's less of the airiness. Bass changes too but not so much as you'd expect.
It's a taste thing really, I feel it sounds tight with more stuffing. But there's less of the airiness. Bass changes too but not so much as you'd expect.
I generally prefer a tighter sound to an airy one, so i guess overstuffing a little bit would be a good idea. Itmon, your method sounds the easiest since i am without a scale, and if im shooting for a little overstuffing, then cutting a 250g bag in half is perfect.
Thanks so much for your guys' help, i will let you know when i get these under way
Thanks so much for your guys' help, i will let you know when i get these under way
