I don't mind going with a rear firing port. I have a couple of dual 8" towers w/ rear firing ports. With rear firing, I could also experiment w/ sealing without without cosmetic problems. WINSID calls for a 4"x10" port. So I hope that works out. (I almost went with a dual 12" sealed, because the box dimensions were almost the same. But I thought that may be overkill against the midrange and tweeter.)
I bumped the dimensions to 15x46x15. (What's a few more inches, the things will be huge anyway.) I will give 33" or 94 liters to the 12" woofer and leave the last 13" or 34 liters for the 6.5 midrange and tweeter. That should go right in line with your recommendations.
The other thing I ALMOST did was go with your sub-sat idea, but use the 6.5. I was going to get the 2-way x-over and build a 2-way box that sits on top of the 12"woofer box. (price of this plan was about the same as the one box 3-way.) Then I could wire them together when I chose. But this required a separate coil in the 12" box then a high pass cap on the 2-way box. That would turn the 2-way into a 1st order 6db and 2nd order 12db bandpass....and I didn't think that you come out correctly. So I went with everything in ONE box...as you suggested in an earlier post.
For transport purposes. I still wouldn't mind finding a way to make 2 boxes. Like this plan...but without the sub amp. http://www.wadsnet.com/~dtenney/dayton_watts.htm
By two boxes, I mean I would put the 3-way crossover in the 2-way box and then wire in the 12" LFD box when it's time to play. I would always play them together. But I guess that would require 2 binding posts on the 6.5 boxes and one on the LFD box. Even though it would be 4 boxes instead of 2 (total) it would be easier to lift and move around. Then I could make the 6.5 box a little smaller and still be well below .70 qtc. This will take up less storage space.
I still my try this. If you have any further brain storms on the best way to do this, please post.
But I thank you greatly for all of your help! This is my first FULL cabinet building project. (I usually retrofit.)
I bumped the dimensions to 15x46x15. (What's a few more inches, the things will be huge anyway.) I will give 33" or 94 liters to the 12" woofer and leave the last 13" or 34 liters for the 6.5 midrange and tweeter. That should go right in line with your recommendations.
The other thing I ALMOST did was go with your sub-sat idea, but use the 6.5. I was going to get the 2-way x-over and build a 2-way box that sits on top of the 12"woofer box. (price of this plan was about the same as the one box 3-way.) Then I could wire them together when I chose. But this required a separate coil in the 12" box then a high pass cap on the 2-way box. That would turn the 2-way into a 1st order 6db and 2nd order 12db bandpass....and I didn't think that you come out correctly. So I went with everything in ONE box...as you suggested in an earlier post.
For transport purposes. I still wouldn't mind finding a way to make 2 boxes. Like this plan...but without the sub amp. http://www.wadsnet.com/~dtenney/dayton_watts.htm
By two boxes, I mean I would put the 3-way crossover in the 2-way box and then wire in the 12" LFD box when it's time to play. I would always play them together. But I guess that would require 2 binding posts on the 6.5 boxes and one on the LFD box. Even though it would be 4 boxes instead of 2 (total) it would be easier to lift and move around. Then I could make the 6.5 box a little smaller and still be well below .70 qtc. This will take up less storage space.
I still my try this. If you have any further brain storms on the best way to do this, please post.
But I thank you greatly for all of your help! This is my first FULL cabinet building project. (I usually retrofit.)
Looks like you're in good shape! I do like your plan.
and I LOVE skyscrapers!!
Didja order yer stuff yet? I just did so moments ago on mine. It's my FIRST-ever retrofit! I have always done fresh cabs. Problem is, I've been procrastinating on a new cab project for about 14 months now... A sealed 8" x 3" x 1" all-Vifa unit. My problem is I design these weird trapezoid boxes so the likelihood for mistakes is high in the woodshop and I end up working on something easier!
This retrofit thing is interesting; learning to operate under constraints and find success with limited flexibility. The old Infinity cabinets I have are ~70 liters with a 2.875"x7.25" rear-firing port (which I will probably end up plugging (or maybe replacing with an aperiodic vent...hmmm)). Once I make a sub-enclosure for the midrange, that doesn't leave much for a 12" woofer. A Dayton Classic 10" would love it, but I dealing with a 12" hole... The top used to have some wierd vertical funnel-shaped foil thing with a magnet under it (probably some sort of stereo-image-ruining HFD fad of the past) sitting in a chamber behind the grilles (has a rear grille) and under the removable top panel, but outside the box itself. It's almost a cubic foot, and that's where I'll build the XO for serviceability (I like doing screw-clamp P2P XOs). Should be fun. Overall they're somewhere around 42-45" tall but I forget exactly at the moment. They've got hardwood sides so I might need some vibe-damping inside...
Good luck to both of us!! I'd say we should keep this thread (or perhaps another named something like "Office Building-Shaped Hi-Fi Speaker Projects") alive with some project photos.
and I LOVE skyscrapers!!
Didja order yer stuff yet? I just did so moments ago on mine. It's my FIRST-ever retrofit! I have always done fresh cabs. Problem is, I've been procrastinating on a new cab project for about 14 months now... A sealed 8" x 3" x 1" all-Vifa unit. My problem is I design these weird trapezoid boxes so the likelihood for mistakes is high in the woodshop and I end up working on something easier!
This retrofit thing is interesting; learning to operate under constraints and find success with limited flexibility. The old Infinity cabinets I have are ~70 liters with a 2.875"x7.25" rear-firing port (which I will probably end up plugging (or maybe replacing with an aperiodic vent...hmmm)). Once I make a sub-enclosure for the midrange, that doesn't leave much for a 12" woofer. A Dayton Classic 10" would love it, but I dealing with a 12" hole... The top used to have some wierd vertical funnel-shaped foil thing with a magnet under it (probably some sort of stereo-image-ruining HFD fad of the past) sitting in a chamber behind the grilles (has a rear grille) and under the removable top panel, but outside the box itself. It's almost a cubic foot, and that's where I'll build the XO for serviceability (I like doing screw-clamp P2P XOs). Should be fun. Overall they're somewhere around 42-45" tall but I forget exactly at the moment. They've got hardwood sides so I might need some vibe-damping inside...
Good luck to both of us!! I'd say we should keep this thread (or perhaps another named something like "Office Building-Shaped Hi-Fi Speaker Projects") alive with some project photos.
Yep, I ordered the stuff today. I wanted to get it while the Dayton crossovers and Dayton 6.5 was still on sale. I also got a few bucks off for buying 4 Dayton silk tweeters. So my stuff should be here by Friday. It will take me a few weeks to get the tower cabinets done. But I'll do my PA stuff and Dayton 2-way retrofit this weekend.
I think I've figured how to split each tower into two boxes so that I can detach the mid/tweet from the woofer. So, hopefully that will turn out ok. If I leave them as one box, it may just be too large to transport around when I need to. One advantage is that I could use the woofers with other satellites if I need to. But together, they will be between 48"-50". If the plan works, I will be able to get by without another subwoofer.
Please let me know how yours works out. (I think you said that you were getting the Goldwood 12".) I'll post here if I have any questions. I think we will both be happy with our projects!
Thanks again for your extensive help.
I think I've figured how to split each tower into two boxes so that I can detach the mid/tweet from the woofer. So, hopefully that will turn out ok. If I leave them as one box, it may just be too large to transport around when I need to. One advantage is that I could use the woofers with other satellites if I need to. But together, they will be between 48"-50". If the plan works, I will be able to get by without another subwoofer.
Please let me know how yours works out. (I think you said that you were getting the Goldwood 12".) I'll post here if I have any questions. I think we will both be happy with our projects!
Thanks again for your extensive help.
Yeah, I didn't even realize the 6.5's were on sale till I got there today. That was cool. Yep, I've got 2x Goldwood GW-12PC-6 on the way too (http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=290-332)...
Good luck on the box split! Sounds like a nice, flexible approach. You could just wire them in parallel (bi-wire) from one amp... Take the woofer components off the crossover (a cap and a coil) and stick them in the LFD box... Cap across woofer terminals, coil in series; then just hook both up to amp as if two speaker systems. You'd maintain the 12 dB slopes on the Dayton XO.
Referring to the attached picture (maybe not worth a thousand words, but here's a try): You wouldn't be changing the circuit any, but in effect you'd be cutting where the "X"s are and attaching (via hooking both up to amp or simply daisy-chaining) where the "Y"s are. The end result will be equal to not having done so, but this will allow two separate environments to each contain a portion of your XO. Bear in mind that the woofer section by itself has a rising inductive reactance with rising frequency, and the mid+tweeter section has a rising capacitive reactance with falling frequency, so it would be best for your amp to not connect one without the other...
In any event, it is my absolute pleasure to offer any help I can. That's the way of diyAudio I believe. Knowledge is like money in that it doesn't accomplish anything in the pocket.
Good luck on the box split! Sounds like a nice, flexible approach. You could just wire them in parallel (bi-wire) from one amp... Take the woofer components off the crossover (a cap and a coil) and stick them in the LFD box... Cap across woofer terminals, coil in series; then just hook both up to amp as if two speaker systems. You'd maintain the 12 dB slopes on the Dayton XO.
Referring to the attached picture (maybe not worth a thousand words, but here's a try): You wouldn't be changing the circuit any, but in effect you'd be cutting where the "X"s are and attaching (via hooking both up to amp or simply daisy-chaining) where the "Y"s are. The end result will be equal to not having done so, but this will allow two separate environments to each contain a portion of your XO. Bear in mind that the woofer section by itself has a rising inductive reactance with rising frequency, and the mid+tweeter section has a rising capacitive reactance with falling frequency, so it would be best for your amp to not connect one without the other...
In any event, it is my absolute pleasure to offer any help I can. That's the way of diyAudio I believe. Knowledge is like money in that it doesn't accomplish anything in the pocket.
Attachments
Update:
I went back and revised my dimensions.
If I make the woofer box 15x32x15, it will give me a volume of 90.6 liters. 4" x approx. 8" port. These dimensions will be perfect for future Dayton upgrades. Because the Dayton Series II and Quattro 12" woofers are direct drop in's for this box. Port size and everything. (Port length within .5" difference) They should all perform well in this enclosure. So if I eventually upgrade my power needs, I will still have usable enclosures.
The mid/tweeter box will be 13x15x13. They will fit into a lip border that will go on top of the woofer box.
I went back and revised my dimensions.
If I make the woofer box 15x32x15, it will give me a volume of 90.6 liters. 4" x approx. 8" port. These dimensions will be perfect for future Dayton upgrades. Because the Dayton Series II and Quattro 12" woofers are direct drop in's for this box. Port size and everything. (Port length within .5" difference) They should all perform well in this enclosure. So if I eventually upgrade my power needs, I will still have usable enclosures.
The mid/tweeter box will be 13x15x13. They will fit into a lip border that will go on top of the woofer box.
That seems pretty appropriate. I noticed all those Dayton 12's were pretty compatible (they just happen to want a little more air than I can offer in my current project). The Quattro will do less volume OK, but it sure would never complain about 90 liters... Maybe you could somehow make ports interchangeable if you wanted to.
I like the box-fit idea; like a routed groove in one and a lip on the other? 4 lighter boxes instead of 2 colossal ones. You could even bleep around with room positioning and fitting them into smaller places... Like the little ones on a shelf and the big ones as impromptu coffee table pedestals - Diggin' it.
Maybe you could somehow make ports interchangeable if you wanted to. I like the box-fit idea; like a routed groove in one and a lip on the other? 4 lighter boxes instead of 2 colossal ones. You could even bleep around with room positioning and fitting them into smaller places... Like the little ones on a shelf and the big ones as impromptu coffee table pedestals - Diggin' it.
Yeah, if I was going to upgrade, I would be more inclined to go with the Dayton Series II. It seems more of a beefed up Classic 12" and seems like a better fit in a 3-way setup. Where the Quatro is all sub.
By the way, how far could the woofer be separated from the mid/tweet before SQ suffers significantly? It's a 375hz x-over point. That's if I wanted to do some room positioning.
By the way, how far could the woofer be separated from the mid/tweet before SQ suffers significantly? It's a 375hz x-over point. That's if I wanted to do some room positioning.
By the way, I was thinking for putting female rca jacks on the back of the mid/tweet boxes and just wire male rca ends to speaker wire to get the signal from the amp/receiver. I was going to use the same method to connect the mid/tweet box to the woofer box.
Is this possible, since the rca end is +/- and speaker wire is +/- ??
Is this possible, since the rca end is +/- and speaker wire is +/- ??
prerunnerv6 said:
I'm not 100% sure of your question... You can use RCA plugs if you like, just avoid small-guage high-capacitance (shielded) cable. Do match + and - markings, except on the midrange (with 12dB XO, the midrange driver should be hooked up oppositely).
Personally, I'd put big connectors on the woofer box, wire the amp to them with speaker wire, then connect another piece of speaker wire from the same terminals to the mid-tweet box. That box can be RCA-terminated if you want. I'd probably use binding posts on all, with stacking banana plugs so that I can daisy-chain the speaker wires with ease. This also gives you polarity control (you may want the mid-tweet polarity to be opposite of the woofer if you place them apart at a distance, depending where you sit).
prerunnerv6 said:
Agreed on the woofers.
That's a good question (uh-oh you say...)
I generally use the same 1/2 wavelength rule of thumb as on driver circumferences, with 1/4 being even better. For example, At 375 Hz, the wavelength is (13,600in/sec)/(375/sec) = 36 inches. If you can keep them within 18 inches, you'll be doing alright, and if you can keep them within 9 inches, you kick butt. That's because if they are less than half a wavelength apart, you can never get a 1/2 wavelength further from one than the other, and you can't possibly have nodes exhibited in the sound field (room). Unfortunately, the mid-tweet at 3kHz gives (13,600in/sec)/(3000/sec) = 4.5" This represents the maximum sum of driver diameters (1/2 WL based on radius) which installed touching each other tangently will allow this rule to be followed. You can't possibly do this, but you can probably sound pretty good with as many wavelengths between the woofer and mid as between the mid and tweeter.
I like the 1/4 WL "rule" since the sound is shared between them for a continuum of frequencies on either side of the crossover point, and this gives you an octave's worth of the 1/2 wavelength rule. If you can set it up such that your listening position is equidistant from the drivers, they can be much farther apart, but that shrinks your "sweet spot" substantially. Picture that if the drivers occupied the same exact location in space you could never get farther from one than the other, and you want to get as close as possible to this. What I have stated here is another opinion-based method of quantifying the problem. It's how I do it. If you do this you'll never hear the speakers "wash" you over with nodes as you stand up from sitting while listening.
You can hear nodes sort of tugging or whooshing at your brain similar to out-of-phase speakers as you pass through them spatially. Try hooking two stereo speakers up in mono, set them some feet apart, say 9 or 10, play some music through them, and walk sideways across in front of them with your eyes closed. It should remind you of the feeling of if you hook them up the same way only out-of phase and just stand in the middle (pushing one ear and pulling the other).
Node positions are defined purely as the locus of points in space which are ODD multples of 1/2 wavelength more farther from one source (driver) than the other (at a frequency of interest; full node mapping is spectral function of frequency). EVEN multiples are anti-nodes, and this is where the summation is complete. Even-order XOs are designed for antinode response.
About the RCA cables...I'm just ill because I forgot to buy extra binding posts from PartsExpress. But I didn't come up with the split box idea until after I ordered. The binding posts I want are only $2 a piece, but they will cost nearly $10 to ship them.
If I would have remembered them on my first order, then they wouldn't have cost anything to ship. (No added shipping cost I mean.) That's why I thought about using some RCA cables I had laying around. I'll probably wait to see if I need something else, then order them.
If you know of anyplace where I can get some speaker terminals cheap, please let me know.
About the speakers...fortunately, I shouldn't have to separate them usually, since I'm splitting them for transport reasons and their main purpose is to play as a 3-way speaker. If I did separate them, it may be to put the mid/tweet on a table top and the woofer right next to the table or in front of the table.
If I would have remembered them on my first order, then they wouldn't have cost anything to ship. (No added shipping cost I mean.) That's why I thought about using some RCA cables I had laying around. I'll probably wait to see if I need something else, then order them. If you know of anyplace where I can get some speaker terminals cheap, please let me know.
About the speakers...fortunately, I shouldn't have to separate them usually, since I'm splitting them for transport reasons and their main purpose is to play as a 3-way speaker. If I did separate them, it may be to put the mid/tweet on a table top and the woofer right next to the table or in front of the table.
Well, I got the PA x-over done. Simple 1st order 6db and 2500hz. Sounds good for PA use. I noticed that the horn tweeter seems to be matching the 10" woofer better. So I didn't wire in the L-pad...which are larger than I expected. So I'm done with the PA boxes.
I did the Dayton 2-way retrofit...6.5 woofer and silk tweeter. I'm impressed the the punchy bass of the woofer. I'm using a stock Dayton x-over at 2000hz, since I already had them. I'm letting them break in this weekend. I will need to tame the tweeter just a little. When I turn my receiver to -2 on the treble, it seems to do the trick. But I'm going to research some mods on the silk tweeter. Off axis response is good though.
Hopefully I'll get my Classic 3-way set done in a couple of weeks. The stock Dayton 3-way x-overs are heavy.
This experience has shown me that I can make my own x-overs and will do so in the future.
I did the Dayton 2-way retrofit...6.5 woofer and silk tweeter. I'm impressed the the punchy bass of the woofer. I'm using a stock Dayton x-over at 2000hz, since I already had them. I'm letting them break in this weekend. I will need to tame the tweeter just a little. When I turn my receiver to -2 on the treble, it seems to do the trick. But I'm going to research some mods on the silk tweeter. Off axis response is good though.
Hopefully I'll get my Classic 3-way set done in a couple of weeks. The stock Dayton 3-way x-overs are heavy.
This experience has shown me that I can make my own x-overs and will do so in the future.
prerunnerv6 said:
Sweet! I don't know much about horn tweeters, but with the light domes I usually use I would be afraid of power handling limitations at that XO frequency with only 6dB slopes...
Me too on the woofer impressions. Those are definitely good XOs. I'd probably stick my L-pads in this pair...
Heavy's good... except for iron cores; they will magnetically saturate at high power throughput. I'm hoping the same thing for a week from now on my retrofit... I am also hoping they're at least 60 pounds each...
They have two weaknesses, the baffle is surrounded by projecting side panels (may tamper with treble and soundfield cleanliness) and tweeter hole is quite a ways from midrange hole...Nice. XOs are actually all I ever meant to do in the first place, I just kinda got sidetracked into speakers as a whole somewhere along the way.
XO's are pretty do-able. If you build them yourself, consider skipping the circuit boards, and doing point to point wiring... Allows spatial separation and decoupling of things particularly inductors... They will talk to each other if they share axis and are nearby (the ol' mutual inductance thang)...After a little more research, I found that quite a few people are using resistors on these Dayton silk tweeters. Anywhere from 3-10 ohms. So I went to Radio Shack and picked up a couple of packs of 10 ohm resistors. Figured that would let me go with either 10 ohms or 5 ohms (parallel). 5 ohms seemed to do it. It took out much of the harshness without making it dull. Killed alot of the "SSSSS" sounds as well.
I found one guy who put some type of Zobel circuit on one of the Dayton stock x-overs. I may or may not try that later. But for now, it's sounding good. The woofer is breaking in and the bass is mellowing out nicely. For casual listening for Internet radio, I'm playing these Dayton 2-ways along with 2 more 2-ways I made from some car component speakers. The Dayton's have more detail and the car speakers a little more bass. Playing them all together...its surprising how much good bass they kick out. Especially close to the wall, which is helping.
I found one guy who put some type of Zobel circuit on one of the Dayton stock x-overs. I may or may not try that later. But for now, it's sounding good. The woofer is breaking in and the bass is mellowing out nicely. For casual listening for Internet radio, I'm playing these Dayton 2-ways along with 2 more 2-ways I made from some car component speakers. The Dayton's have more detail and the car speakers a little more bass. Playing them all together...its surprising how much good bass they kick out. Especially close to the wall, which is helping.
Here's another thread here on DIY Audio regarding the Pioneers just in case someone didn't know about it:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=60632&perpage=10&pagenumber=1
http://www.diyaudio.com/forums/showthread.php?s=&threadid=60632&perpage=10&pagenumber=1
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