hello all,
i've decided to try my first speaker build...
Im a sound tech for a local rock band. as such, I'm constantly looking to learn more. and to that, I'm a very hands on learner. hence my want to build from scratch. (probably a big mistake http://files.diyaudio.com/forums/images/smilies/mad.gif)
here are the basic specs I'm starting with....
all drivers are Eminence
Delta 15 8 ohm 400watt 48-4000hz 100spl
Beta 10(sealed back) 8ohm 200watt 300-4000hz 99.6spl
psd2002 8ohm 80watt 1200-20000hz 105spl
Jbl hm25-25 waveguide 90 x 60
Cabinets are trapezoidal in design, with the 15" being baffled into its own chamber approx. 1.7 cu ft.(sealed) With the 10" and the compression driver sharing the same space. basic cabinet dimensions being 40.625H x 18W x 12D (basic internal dimensions). built from .75" plywood.
CL between 15" and 10" is approx. 16" and CL between n10" and CD is approx. 11.75". so my quandary is..... where did i mess up and whats likely to be my worst problem. (I'm just starting to learn about lobing and phase.) these are intended for medium to large bars and outdoors.
also, they will be trip-amped.... Qsc gx5"s(lows and mids) Qsc gx3(highs). controlled through Dbx driverack. but I've also tossed around the crazy notion to go the route of building passive crossovers with single amplifier.
and to the crossover conundrumn... i would like to utilize jeff bagby's crossover designer. does anyone use this on Mac without running windows on parallel?
any information would be greatly appreciated.....
i've decided to try my first speaker build...
Im a sound tech for a local rock band. as such, I'm constantly looking to learn more. and to that, I'm a very hands on learner. hence my want to build from scratch. (probably a big mistake http://files.diyaudio.com/forums/images/smilies/mad.gif)
here are the basic specs I'm starting with....
all drivers are Eminence
Delta 15 8 ohm 400watt 48-4000hz 100spl
Beta 10(sealed back) 8ohm 200watt 300-4000hz 99.6spl
psd2002 8ohm 80watt 1200-20000hz 105spl
Jbl hm25-25 waveguide 90 x 60
Cabinets are trapezoidal in design, with the 15" being baffled into its own chamber approx. 1.7 cu ft.(sealed) With the 10" and the compression driver sharing the same space. basic cabinet dimensions being 40.625H x 18W x 12D (basic internal dimensions). built from .75" plywood.
CL between 15" and 10" is approx. 16" and CL between n10" and CD is approx. 11.75". so my quandary is..... where did i mess up and whats likely to be my worst problem. (I'm just starting to learn about lobing and phase.) these are intended for medium to large bars and outdoors.
also, they will be trip-amped.... Qsc gx5"s(lows and mids) Qsc gx3(highs). controlled through Dbx driverack. but I've also tossed around the crazy notion to go the route of building passive crossovers with single amplifier.
and to the crossover conundrumn... i would like to utilize jeff bagby's crossover designer. does anyone use this on Mac without running windows on parallel?
any information would be greatly appreciated.....
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Well.. your first mistake was probably not asking for help before you made sawdust but maybe you only just found this website so I can't fault you on that too much.
The best way to go about building a speaker is to first define your goals. In your case we know it will be a band PA so what are your requirements and limitations there...
- How loud do you need it to be? How large a room or how many people.
- How much storage and transport space do you have?
- How heavy an object can you or you band members lift?
- How much money do you have to spend?
Ok now we can get into the basics of PA. The first thing you need to know is the best bass response is obtained with the low frequency speakers on the ground, but the best coverage position for mids and highs is overhead. As a result most PA systems are broken into 2 types of boxes.. relatively large subs that remain on the ground and smaller mid/hi boxes that are either stacked on the subs or flown or stand mounted overhead.
Now when you get into designing the speakers themselves there are software tools available that will take the performance specs(Theile small parameters) of a low frequency driver and define the size(volume) of enclosure needed to get optimum performance. Typically pro sound speakers are bass reflex loaded(ported) as this technique enhances bass output without costing additional amp power, sealed enclosures are reserved for mids or horn loaded designs.
So where does that leave you. Unfortunately the bass driver you picked is not at all suitable for a small sealed enclosure.. response falls off fast below about 80hz, and even if you removed the separation in your box which would be OK for the other drivers because they are sealed things would not improve much.
So given that what would you like to do next? I don't suggest trying to utilize this driver in a larger box because that box would be hugh(refridgerator sized), so to utilize the boxes you have you need different drivers. But if you aren't opposed to starting over from scratch then I'm sure you will get all kinds of suggestions on building something much better.
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Thank you for your response Conanski!!
Unfortunately, I suffer from jump in and learn as I go... ��
And knowing just enough to be dangerous.
-The crowd I'm running for can vary largely, but on the outside for this rig(clubs and bars), approx 300-500.
-how loud.... I don't want ears to bleed. ����
-room and transport are not an issue(large bandroom and trailer to transport)
-money to spend.... Fair backing, but not not new powered cabinets backing.(EV Jbl)
Additional gear... I do run a pair of 18" powered subs(I know I do it wrong.... Cabs on subs, set on outboard corners. It's what I have to do for the environments we play in.)
To that I'm not too concerned with the 80hz roll off. Only vocals, guitar and drums are run through the main stacks. Kick, bass are piped in the subs(lite mix of floor Tom also).
Unfortunately, I didn't start with computer modeling(obviously). Eminance literature recommended a sealed box of 1.2 cu. ft., yes with a step roll off at approx 100-120 he, which is why I went 1.7 cu. ft.(to give a little more "breathing room" for the driver).
I'm not opposed to fitting another low driver in the cabinet and making some mods.
Unfortunately, I suffer from jump in and learn as I go... ��
And knowing just enough to be dangerous.
-The crowd I'm running for can vary largely, but on the outside for this rig(clubs and bars), approx 300-500.
-how loud.... I don't want ears to bleed. ����
-room and transport are not an issue(large bandroom and trailer to transport)
-money to spend.... Fair backing, but not not new powered cabinets backing.(EV Jbl)
Additional gear... I do run a pair of 18" powered subs(I know I do it wrong.... Cabs on subs, set on outboard corners. It's what I have to do for the environments we play in.)
To that I'm not too concerned with the 80hz roll off. Only vocals, guitar and drums are run through the main stacks. Kick, bass are piped in the subs(lite mix of floor Tom also).
Unfortunately, I didn't start with computer modeling(obviously). Eminance literature recommended a sealed box of 1.2 cu. ft., yes with a step roll off at approx 100-120 he, which is why I went 1.7 cu. ft.(to give a little more "breathing room" for the driver).
I'm not opposed to fitting another low driver in the cabinet and making some mods.
You could use WIN ISD WinISD - Linearteam to plug in the TS Parameters, as a bit of a guide. Not keen on you placing a second driver in the same cab, err, do the calcs first as suggested above. You could intro a second set of cabs for some solid 50 to 100Hz bass and fill the gap between your subs and existing project.
agree that your existing project won't be "bess endowed" with 80Hz sudden roll offand would require a re think/make. How does another set of bins sound ? probably reflex helmholtz resonator type, they would be approximately a bit over 1 third larger in internal volume or more.
Crossovers, go active if you are tri amping, fiddle with actual room response and EQ on set up per channel, makes thing a little more simple.
Enjoy
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Well knowing that you have subs the low freq response of these isn't as much of an issue, ideally a speaker this size should be able to operate on it's own and deliver decent "fullrange" sound but what you have will work as they are. I'm going to suggest 800hz and 2.5khz LR24 crossovers to start, dial those into the driverack and have a listen and then maybe give the auto EQ a shot at taming them. The thing to know about corrective EQ is unless you can setup outdoors away from structures you are measuring the room as much as the speakers, so try that if you can and save it as a baseline EQ preset.
So in your opinion, is this an viable option(viable enough). The cabinets are not "built". I have all the panels cut to size and shape. Pretty much ready for assembly. Knowing that this Driver isn't truly correct. Could I swap out the driver, remove the baffling for the low driver, vent the case..... To gain more chamber size. Also, do you know of a driver that would be usable in this cabinet size? I think I could scratch up another $150/ driver for a swap out , if that's an option. Or honestly, am I just barking up the wrong tree.
Worst case scenario..... I do a redesign and rebuild!!!
I appreciate your suggestions and help, truly!!! Those crossover settings are damn near what I was thinking. Eminance Is suggesting 2500hz LR12 for the high driver. But I can set that separate from the mids, and go from there.
Worst case scenario..... I do a redesign and rebuild!!!
I appreciate your suggestions and help, truly!!! Those crossover settings are damn near what I was thinking. Eminance Is suggesting 2500hz LR12 for the high driver. But I can set that separate from the mids, and go from there.
How much chamber size can you gain? If you get to about 4 cubic feet you could use the delta pro 15 for a full-range-ish cab. Sort of x-max limited but for full range music without too much bump it's ok (50 hz). And quite efficient - the real half space (not marketing) SPL comes in at 98db. For a more full range, use the kappa 15LF (steel frame version). That will get you maddeningly close to 40 hz in 4 cubes (will do it in 5). Costs 2db - it is really 96db/2.83v. Neither will do crazy high levels without subs, but use a sub and you can get full power handling. Or run subless up to about 400 watts.
Yes what would the total internal volume be with the divider removed. You wouldn't lose much volume with ports for a 40hz or even 50hz tuning.. something you could potentially add pretty easily with a slot port at the bottom.
P.S. After looking at your pics again you don't have room at the bottom for ports, but if you're open to mods then I'd suggest cutting a new baffle with driver spacing minimized and that should free up enough space for a slot port across the bottom or even a couple corner ports.
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This is awesome guys!!! Ill have to run the numbers again, but i think it came in around 4.5-4.6 cubes, with the baffle removed. Also, i should be able to run approx. 2.5” corner vents without trouble. What about rear venting? The back is 13” corner to corner, so i could do about 11.5” wide slot vent??
At this point, I’m leaning towards the Kappa 15 Lf. At band practice tonight, I’ll do another calculation of the cabinet interior volume. If somebody could help me just figuring out what I need for Vents I would appreciate it. As of right now, I don’t have a Windows computer. So my limitations of software would be major hindrance on me figuring this out.
I converted to Mac OS X a couple years ago.
I converted to Mac OS X a couple years ago.
Yes that will work fine, did you try to download WinISD? These Eminence drivers are all preloaded.
I have attached a screenshot of these drivers modeled with it bases on your box volumes and porting that I think is optimized for the Kappa15lf, the difference in low freq performance between these is not subtle.
I have attached a screenshot of these drivers modeled with it bases on your box volumes and porting that I think is optimized for the Kappa15lf, the difference in low freq performance between these is not subtle.
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