AVS Forum banner
1 - 20 of 42 Posts

·
Registered
Joined
·
881 Posts
Discussion Starter · #1 ·
got a steal of a deal on craigslist. unfortunately i dont really know what the hell im doing when it comes to DIY



$400 which included both cabinets AND these drivers installed!
http://www.madisound.com/catalog/pro...roducts_id=822
http://www.madisound.com/catalog/pro...roducts_id=777


The cabinet dimensions are 12" (at the widest) x 13" depth x 45" height


No crossover or tweeter. The counter sunk driver hole for the tweeter is 113mm. Im looking at these tweeters:
http://www.madisound.com/catalog/pro...oducts_id=1389
http://www.madisound.com/catalog/pro...roducts_id=227
http://www.madisound.com/catalog/pro...roducts_id=226


im leaning towards the foundtek


once i order the tweeter and it arrives im going to test the fitting, then im going to have madisound create the crossover for me with their leap software. I know nothing about crossover design.


the back is not ported, so i guess these are made to be sealed and not ported. Im basically going to be keeping them that way. I figure its better to leave the board in there as well to keep the 10" in its own sealed chamber.


as for acoustic damping im thinking 3/4" or 1/2"?

whats the difference between the 3 layer one?
http://www.parts-express.com/pe/show...number=260-520
http://www.parts-express.com/pe/show...number=260-530

from what ive figured 7 sheets of the stuff will cover all walls of the two speakers (although this is assuming i put the stuff on the rear of the baffles. are you supposed to do that?)


binding posts im almost certainly going for these
http://www.parts-express.com/pe/show...number=091-620
http://www.parts-express.com/pe/show...number=091-600


pics



 

·
Registered
Joined
·
2,037 Posts
Looks like a pretty sweet find to me. As long as you can get the x-over figured out properly you should have a nice set of towers. Why did the guy sell them in the first place? Crack addiction he needed to support? LOL, sorry i just cant see starting a project especially like that and not seeing it through. And then to let it go for half of what you have into it! INASNITY! Keep us posted. Im with youat the moment lost in the world of DIY speakers biting off more than i can chew. Hopefully the end result will have been worth the time for you.
 

·
Registered
Joined
·
7,537 Posts
Those drivers are pretty nice I bet.


Looks like he knew more about woodworking than building speakers. The spacing between the mid/tweeter is farther than I'd be comfortable with. The midrange cabinet volume looks pretty large. Don't know how well the back panel will seal up with those few screws and no foam or any "ledge" to seal onto. And I'd prefer to have more bracing. But some of the old-pros around here would know more than me.


The cabinets are very pretty though. Verry nice craftsmanship.


If the speaker spacing ends up being okay, then I think you could rework those cabinets by making the midrange enclosure volume smaller and the woofer volume larger, as well as adding a vent out the back. Put some more bracing in. Then make something for the rear cover to screw onto and make it airtight.
 

·
Registered
Joined
·
881 Posts
Discussion Starter · #4 ·

Quote:
Originally Posted by CZ Eddie /forum/post/18264056


Those drivers are pretty nice I bet.


Looks like he knew more about woodworking than building speakers. The spacing between the mid/tweeter is farther than I'd be comfortable with. The midrange cabinet volume looks pretty large. Don't know how well the back panel will seal up with those few screws and no foam or any "ledge" to seal onto. And I'd prefer to have more bracing. But some of the old-pros around here would know more than me.


The cabinets are very pretty though. Verry nice craftsmanship.


If the speaker spacing ends up being okay, then I think you could rework those cabinets by making the midrange enclosure volume smaller and the woofer volume larger, as well as adding a vent out the back. Put some more bracing in. Then make something for the rear cover to screw onto and make it airtight.

The thing is he actually had these built by a local cabinet maker. Im guessing these were one of his first forays into diy.


How big should the midrange cabinet be? and how much bigger does the cabinet for the woofer need to be?


I would probably prefer to keep these sealed, im not going to run them with a sub for music but i dont want to rear port them simply because placement becomes pretty difficult with my somewhat confined space.


Ive had people comment about the tweeter to midrange distance, how big of a deal do you think it is? I can always cut another hole above the midrange possibly and then maybe make a big "pill" shape with the hole beneath it (its complicated so i may need to sketch it) then fill that in with something. Right now the aesthetics of the speakers are pretty important to me because of the cabinetry being so high grade, so i would rather not touch the front at all. As for bracing i guess ill glue some 1x2s in there or something.


edit: also i think ill throw a 1" lip around the rear of the cabinet and then put some gasket along the whole thing so when i screw in the back with the 5 holes it *should* be air tight
 

·
Registered
Joined
·
7,537 Posts

Quote:
Originally Posted by omegaslast /forum/post/18264395


The thing is he actually had these built by a local cabinet maker.

Wow, then he really lost some money on this project. $600 in drivers and he probably spent at least as much on the cabinets.


Quote:
Originally Posted by omegaslast /forum/post/18264395


How big should the midrange cabinet be?

I dunno. If you don't get an answer on this thread, then maybe you could post the question here:

http://www.htguide.com/forum/forumdisplay.php4?f=6


Quote:
Originally Posted by omegaslast /forum/post/18264395


how much bigger does the cabinet for the woofer need to be?

Best thing to do is ask Madisound when they work up a crossover for you. Or use WinISD to model the woofer.

What you have right now is somewhere around 1 cu.ft.


Quote:
Originally Posted by omegaslast /forum/post/18264395


I would probably prefer to keep these sealed, im not going to run them with a sub for music but i dont want to rear port them simply because placement becomes pretty difficult with my somewhat confined space.

How about front porting them?

Btw, If these are going to be close to a wall, then you'll want to reduce the BSC in the crossover.


Quote:
Originally Posted by omegaslast /forum/post/18264395


i think ill throw a 1" lip around the rear of the cabinet and then put some gasket along the whole thing so when i screw in the back with the 5 holes it *should* be air tight

Sounds like a plan. You'll probably need to add some wood filler to the areas where the lip sections don't butt up properly to each other.




Curt C has some experience with the tweeter you want to use.
http://speakerdesignworks.com/



Btw, is that .5" or 3/4" wood? I can't tell from the pictures.
 

·
Registered
Joined
·
7,537 Posts
I really like how the cabinet builder kept the grain flowing with the bottom & top side panel at the cut.

 

·
Registered
Joined
·
1,694 Posts

Quote:
Originally Posted by omegaslast /forum/post/18264395


The thing is he actually had these built by a local cabinet maker. Im guessing these were one of his first forays into diy.


How big should the midrange cabinet be? and how much bigger does the cabinet for the woofer need to be?


I would probably prefer to keep these sealed, im not going to run them with a sub for music but i dont want to rear port them simply because placement becomes pretty difficult with my somewhat confined space.


Ive had people comment about the tweeter to midrange distance, how big of a deal do you think it is? I can always cut another hole above the midrange possibly and then maybe make a big "pill" shape with the hole beneath it (its complicated so i may need to sketch it) then fill that in with something. Right now the aesthetics of the speakers are pretty important to me because of the cabinetry being so high grade, so i would rather not touch the front at all. As for bracing i guess ill glue some 1x2s in there or something.


edit: also i think ill throw a 1" lip around the rear of the cabinet and then put some gasket along the whole thing so when i screw in the back with the 5 holes it *should* be air tight

The midrange chamber should be much smaller. The theoretical size would work out to about .1 cu-ft. I would increase that to about .3 cu-ft and use lots of foam or fiberglass damping.


The woofer section should be about 1.7 cu-ft or larger. You could cut some openings in the divider. Depending on your room and bass tastes, you could go over 3 cu-ft. At 1.7 or 2 cu-ft, the f3 will be in the low 40s, and should be more than adequate without a sub.


For a tweeter, I would find one that can be crossed very low due to the spacing between it and the mid. The Dayton RS28s is reported to be good for a very low x-over. The spacing might not be that much of a problem, but it will tend to make the listening height a little more critical. If you don't mind tilting the cabinet slightly to adjust it, then it will be less of an issue. I have a speaker that the spacing is about 9.5 inches, and it is OK. Closer would have been better though.


Here's a tweeter that is 110mm. Might be worth considering.
http://www.madisound.com/catalog/pro...roducts_id=569
 

·
Registered
Joined
·
881 Posts
Discussion Starter · #8 ·

Quote:
Originally Posted by CZ Eddie /forum/post/18265210


Wow, then he really lost some money on this project. $600 in drivers and he probably spent at least as much on the cabinets.


I dunno. If you don't get an answer on this thread, then maybe you could post the question here:

http://www.htguide.com/forum/forumdisplay.php4?f=6


Best thing to do is ask Madisound when they work up a crossover for you. Or use WinISD to model the woofer.

What you have right now is somewhere around 1 cu.ft.


How about front porting them?

Btw, If these are going to be close to a wall, then you'll want to reduce the BSC in the crossover.


Sounds like a plan. You'll probably need to add some wood filler to the areas where the lip sections don't butt up properly to each other.


Curt C has some experience with the tweeter you want to use.
http://speakerdesignworks.com/



Btw, is that .5" or 3/4" wood? I can't tell from the pictures.

I would probably be fine with front porting it but im still a little apprehensive about cutting into the front of it with a router + jasper jig cuz it would be a big pain in the ass no doubt plus gotta buy the jasper jig. plus could screw up the finish...

Quote:
Originally Posted by kbgl /forum/post/18267157


The mirange chamber should be much smaller. The theoretical size would work out to about .1 cu-ft. I would increase that to about .3 cu-ft and use lots of foam or fiberglass damping.


The woofer section should be about 1.7 cu-ft or larger. You could cut some openings in the divider. Depending on your room and bass tastes, you could go over 3 cu-ft. At 1.7 or 2 cu-ft, the f3 will be in the low 40s, and should be more than adequate without a sub.


For a tweeter, I would find one that can be crossed very low due to the spacing between it and the mid. The Dayton RS28s is reported to be good for a very low x-over. The spacing might not be that much of a problem, but it will tend to make the listening height a little more critical. If you don't mind tilting the cabinet slightly to adjust it, then it will be less of an issue. I have a speaker that the spacing is about 9.5 inches, and it is OK. Closer would have been better though.


Here's a tweeter that is 110mm. Might be worth considering.
http://www.madisound.com/catalog/pro...roducts_id=569

That tweeter can play lower than the ribbon im guessing. Also whats very low? like 2000hz?


as for the sizes of the enclosures for the woofer do you think it would have an f3 of 40hz sealed with 2 cu ft? what about 3 cu ft?


this project is on hold right now and in storage, next weekend ill take some better pictures, measure everything, and figure out exactly what modifications im doing to the cabinet.
 

·
Registered
Joined
·
881 Posts
Discussion Starter · #9 ·

Quote:
Originally Posted by CZ Eddie /forum/post/18266027


I really like how the cabinet builder kept the grain flowing with the bottom & top side panel at the cut.


yeah these look at or above retail. Im definitely thinking in the future of going to the shop with a speaker design with a much better designed cabinet. He said he paid about $600 for the pair of cabinets, i figure thats a pretty damn good price considering how much MASS produced cabinets go for on madisound/parts express that IMO are a far cry from retail products and cost almost the same!
 

·
Registered
Joined
·
1,694 Posts

Quote:
Originally Posted by omegaslast /forum/post/18268888


I would probably be fine with front porting it but im still a little apprehensive about cutting into the front of it with a router + jasper jig cuz it would be a big pain in the ass no doubt plus gotta buy the jasper jig. plus could screw up the finish...




That tweeter can play lower than the ribbon im guessing. Also whats very low? like 2000hz?


as for the sizes of the enclosures for the woofer do you think it would have an f3 of 40hz sealed with 2 cu ft? what about 3 cu ft?


this project is on hold right now and in storage, next weekend ill take some better pictures, measure everything, and figure out exactly what modifications im doing to the cabinet.

A 2k x-over is relatively low. A 1.5 x-over is low, and 1k is extremely low. A lot depends on how loud you want to play the speakers, and not all tweeters work well with a low x-over.


A 1.8 cu-ft box should have a lower f3 than one that's 3 cu-ft. (Based on my simple calculations.)
 

·
Registered
Joined
·
21,345 Posts
i'd throw them in the trash and build a horn loaded two-way like parham, geddes, or zilch. sorry if that isn't what you wanted to hear.
 

·
Registered
Joined
·
881 Posts
Discussion Starter · #12 ·

Quote:
Originally Posted by LTD02 /forum/post/18269151


i'd throw them in the trash and build a horn loaded two-way like parham, geddes, or zilch. sorry if that isn't what you wanted to hear.

thanks for the info. youre a real asset to this forum. pat yourself on the back.
 

·
Registered
Joined
·
881 Posts
Discussion Starter · #13 ·

Quote:
Originally Posted by kbgl /forum/post/18269089


A 2k x-over is relatively low. A 1.5 x-over is low, and 1k is extremely low. A lot depends on how loud you want to play the speakers, and not all tweeters work well with a low x-over.


A 1.8 cu-ft box should have a lower f3 than one that's 3 cu-ft. (Based on my simple calculations.)

So a smaller sealed box has a lower f3 than a bigger one?? hmm, thats a big confusing
 

·
Registered
Joined
·
21,345 Posts
"thanks for the info. youre a real asset to this forum. pat yourself on the back."


if you want to get into it, for the cost of modifying the speakers in the o.p., a much better solution can be had. have a look at the econowave project at audiokarma. cheap drivers, cheap horn, cheap enclosure, cheap crossover...awesome performance. i have no idea how you could equal such performance given all the crossover engineering, parts, room treatments, etc. that will be required with your speakers. sorry if you don't like what i have to say, but i'd still cut your losses short and sell those to another guy and build some real speakers. maybe that is what the previous owner decided to do?
 

·
Registered
Joined
·
21,345 Posts
omegaslast, you might think that i am just being an a-hole, but i really am not. i just want to see you end up with the best build possible for the least bucks. in my estimation that is a speaker very, very different from what you have going. however, there are many paths to audio nirvana, whatever path you choose, i wish you the best man.
 

·
Registered
Joined
·
881 Posts
Discussion Starter · #16 ·

Quote:
Originally Posted by LTD02 /forum/post/18269217


"thanks for the info. youre a real asset to this forum. pat yourself on the back."


if you want to get into it, for the cost of modifying the speakers in the o.p., a much better solution can be had. have a look at the econowave project at audiokarma. cheap drivers, cheap horn, cheap enclosure, cheap crossover...awesome performance. i have no idea how you could equal such performance given all the crossover engineering, parts, room treatments, etc. that will be required with your speakers. sorry if you don't like what i have to say, but i'd still cut your losses short and sell those to another guy and build some real speakers. maybe that is what the previous owner decided to do?

i might get into this more later but you havent sold me at all.


Why are two way horn speakers so much better than a 3 way design with a nice 10" woofer, nice 5" midrange, and a nice tweeter? (Lets assume im going to actually end up modifying the front of the cabinet so the midrange isnt so far away, and possibly add a front facing port, although i still would like to entertain the possibility of keeping them sealed.)


are they objectively better or subjectively? btw these are mainly going to be used for 2 channel music, so getting speakers from gedlee (which all but the largest require a sub) makes no sense. a ported 2 way horn speaker is good and all for full range but what makes them better for music.


If 2 way horns were so amazingly better than conventional loud speakers you would think zaph audio and gravesen's webpage would be filled with them.. but they arent.
 

·
Registered
Joined
·
3,880 Posts
This design is almost done.


1. Get a nice 1" silk dome tweeter in your price range.


2. You don't need esoteric and expensive "stuffing". Just slap in

some polyfil from Walmart in the midrange chamber, loosely filled, but

packed. It should work like a champ and give you nice midrange

sound. Lightly fill the bass section with polyfil.


3. Have Madisound build you the crossover.


4. Crank some tunes and you are set. The resell value should be nice

if you get bored with them.
 

·
Registered
Joined
·
2,093 Posts
Nice looking enclosure, but as others have said, the mid-woofer to tweeter spacing is problematic. Is it possible you could buy a matching mid-woofer, tweeter and make this an MTM project?
 

·
Registered
Joined
·
1,511 Posts

Quote:
Originally Posted by mobius /forum/post/18270574


Nice looking enclosure, but as others have said, the mid-woofer to tweeter spacing is problematic.

Is it? It depends. Jon Marsh's M8ta design:


Quote:
Originally Posted by CZ Eddie /forum/post/0


I dunno. If you don't get an answer on this thread, then maybe you could post the question here:

http://www.htguide.com/forum/forumdisplay.php4?f=6

That says a lot... I would follow that advice, but HTguide may or may not be friendlier. It all depends on how much caffeine we've had when we read your post. You have very expensive drivers. With the right tweeter and crossover and a little modification of your boxes, you can probably have an excellent speaker. Your best bet would be to get the crossover designed by an experience person, such as Jed K., Rick Craig, Curt C., CJD or a few others who.
 

·
Registered
Joined
·
1,694 Posts

Quote:
Originally Posted by omegaslast /forum/post/18269174


So a smaller sealed box has a lower f3 than a bigger one?? hmm, thats a big confusing

Assume that 1.8 cu-ft (plus or minus 10%) has the lowest f3 of 43 hz (approx.). Going bigger will gradually move the f3 up toward 50 hz. Going smaller will also gradually move the f3 up toward 50 hz. The shape of the rolloff is a little different though.


Take for example, your midrange box size. You can leave it as it is now as suggested by thylantyr, or make it smaller as I suggested. Both will work just fine. But, if you look at the manufacturers frequency response graph where it shows a nice flat response from 200 hz through 1k, the response at 400 hz and below would start rolling off earlier in the bigger box. This is OK, but your x-over requirements may change slightly to compensate for the rolloff. I think the bigger well stuffed box would actually be better for midrange quality.


A sealed f3 of 43 hz should have all the low end you want for music. If you wanted more deep bass, a bigger ported box would be needed. I didn't actually calculate the size, but likely 4 cu-ft or more. I'll run the numbers in the next day or two to confirm the size. I don't think your box is big enough to go ported.


If you can rework the tweeter hole, there are more smaller flange tweeters to chose from. Don't worry too much about the spacing, just plan around it. I have several ideas already. What is the center to center spacing?
 
1 - 20 of 42 Posts
Top