So I'm very much a novice when it comes to building speakers and need some help. For those of you that attended Lone Star Audio Fest, I'm the lucky guy that won the horns from Pi Audio (pictured below).
Its been a few weeks since Lone Star and things have settled down, so now its time to start figuring out how to do these horns justice.
Here is a little background on things to help:
Horn info: They were made by Bill Martinelli and they’re 800Hz horns with a conical throat and hybrid expansion. They’re not CD, but relatively close, and benefit from mass-rolloff compensation just like CD horns do. They mount a standard bolt-on 1” driver.
My room: I do not have 2 corners and it is fairly small. It is 10' deep x 14' wide with the rear wall being 38" tall and overlooking the entrance. So I cant do corner loaded horns, or large boxes either.
Wayne Parham and I exchanged some emails and he suggested some drivers to me. For the tweeter I think I am going to go with the B&C DE250-8 but am open to suggestions.
What I'm struggling with is what driver to use for the low-end/midrange driver, and MOST importantly how to build a crossover. Wayne suggested the Eminence Definimax 4012HO 12” driver, but I want to make sure there isn't anything out there better. He also suggested that whatever I choose be a high-efficiency 10” or 12” driver that is capable of smooth response up to 1500Hz or so
My goal is to build a 2 way speaker with the horn on top with a ported box for the bottom end. That ported box will be using a driver in the 10-12" range in a form fairly compact box that can dig down to around 40hz.
I spent most of last night looking at and I was either finding drivers that would dig deep enough but had low sensitivity (like the regular 8 ohm Tang Bang full range drivers), or ones with really high sensitivity but wouldn't go that deep.
As I'm not super good with WinISD modeling the every possible driver as I was looking at them wasn't an option from a time or technical perspective....
My goal is that the resulting speaker has a sensitivity as high as possible to allow for use with flea power amps, such as tubes, or Class A solid state amps, but housed in a fairly compact box.
The horn is 17" wide x 5.5" tall x 10.5" deep so at min I wanted to try and keep the box size barely wider than the horn's width, and also a bit deeper than the horn as well to account for the depth with the tweeter mounted to it.
So in thinking of box size, I was hoping for a driver that would work in a box along the lines of 17-19 inches wide x 15-20 inches tall x 10 - 12 inches deep in a ported box....
This morning I remembered that DIYSoundGroup has a bunch of kit options and most of them use waveguides, but more importantly larger pro drivers in fairly small-ish boxes....
So I started looking and found this gem of a kit which uses an off the shelf Eminence Delta Pro-12A...
The info on this kit says "The Tempest is vented and provides bass extension to 40hz (-3db) with a little extra kick in the mid and upper bass range"... and the flatpack for this driver is sized at: 14.5" x 26" x 14.25" deep, 2 cu ft net when used with ports
Now I realize this kit and what I'm doing are not exactly the same, however I think with some modeling I can play with that driver and get it to work for my setup.....
If I tweak the box size a bit as long as I keep the internals close and port it right I should be ok....
Alternately there is a smaller version of this same kit that uses the Eminence Delta-10A, so I may also play around with that driver. As configured that kit only hits 55hz and I'm guessing that it due to driver limitations, so the Delta Pro-12A may be the driver to pick.
I have no idea thought how I'm going to overcome the fact that both drivers will be 8 ohms, so I either have a 16 ohm load, which isnt ideal for any amp, or a 4 ohm load which may be a problem for a lot of amps.
Additionally I have no idea how to approach building a crossover to mate the two drivers together, so any and all help or feedback is appreciated.
I haven't bought anything yet so if I'm heading off on the wrong path, help me correct it now before I open up my wallet.
Its been a few weeks since Lone Star and things have settled down, so now its time to start figuring out how to do these horns justice.
Here is a little background on things to help:
Horn info: They were made by Bill Martinelli and they’re 800Hz horns with a conical throat and hybrid expansion. They’re not CD, but relatively close, and benefit from mass-rolloff compensation just like CD horns do. They mount a standard bolt-on 1” driver.
My room: I do not have 2 corners and it is fairly small. It is 10' deep x 14' wide with the rear wall being 38" tall and overlooking the entrance. So I cant do corner loaded horns, or large boxes either.
Wayne Parham and I exchanged some emails and he suggested some drivers to me. For the tweeter I think I am going to go with the B&C DE250-8 but am open to suggestions.
What I'm struggling with is what driver to use for the low-end/midrange driver, and MOST importantly how to build a crossover. Wayne suggested the Eminence Definimax 4012HO 12” driver, but I want to make sure there isn't anything out there better. He also suggested that whatever I choose be a high-efficiency 10” or 12” driver that is capable of smooth response up to 1500Hz or so
My goal is to build a 2 way speaker with the horn on top with a ported box for the bottom end. That ported box will be using a driver in the 10-12" range in a form fairly compact box that can dig down to around 40hz.
I spent most of last night looking at and I was either finding drivers that would dig deep enough but had low sensitivity (like the regular 8 ohm Tang Bang full range drivers), or ones with really high sensitivity but wouldn't go that deep.
As I'm not super good with WinISD modeling the every possible driver as I was looking at them wasn't an option from a time or technical perspective....
My goal is that the resulting speaker has a sensitivity as high as possible to allow for use with flea power amps, such as tubes, or Class A solid state amps, but housed in a fairly compact box.
The horn is 17" wide x 5.5" tall x 10.5" deep so at min I wanted to try and keep the box size barely wider than the horn's width, and also a bit deeper than the horn as well to account for the depth with the tweeter mounted to it.
So in thinking of box size, I was hoping for a driver that would work in a box along the lines of 17-19 inches wide x 15-20 inches tall x 10 - 12 inches deep in a ported box....
This morning I remembered that DIYSoundGroup has a bunch of kit options and most of them use waveguides, but more importantly larger pro drivers in fairly small-ish boxes....
So I started looking and found this gem of a kit which uses an off the shelf Eminence Delta Pro-12A...
The info on this kit says "The Tempest is vented and provides bass extension to 40hz (-3db) with a little extra kick in the mid and upper bass range"... and the flatpack for this driver is sized at: 14.5" x 26" x 14.25" deep, 2 cu ft net when used with ports
Now I realize this kit and what I'm doing are not exactly the same, however I think with some modeling I can play with that driver and get it to work for my setup.....
If I tweak the box size a bit as long as I keep the internals close and port it right I should be ok....
Alternately there is a smaller version of this same kit that uses the Eminence Delta-10A, so I may also play around with that driver. As configured that kit only hits 55hz and I'm guessing that it due to driver limitations, so the Delta Pro-12A may be the driver to pick.
I have no idea thought how I'm going to overcome the fact that both drivers will be 8 ohms, so I either have a 16 ohm load, which isnt ideal for any amp, or a 4 ohm load which may be a problem for a lot of amps.
Additionally I have no idea how to approach building a crossover to mate the two drivers together, so any and all help or feedback is appreciated.
I haven't bought anything yet so if I'm heading off on the wrong path, help me correct it now before I open up my wallet.
Flea power amps, medium sized woofers and deep bass dont go so well together
In a room thats 10 x 14 empty, which it isnt so your more like 6 feet from the speakers if that, I'd hazard you wont need a ton of power to get more than adequately loud, especially when the drivers I'm looking at are 8 ohm 96db+ efficient.
Also I should mention I'm not focusing on just 6-8" drivers. My intent was to look mainly at 10 and 12" drivers, its 15's that get to be too big. That and the driver needs to fit into what I'd consider a smallish box (for that size of a driver). I'm not looking for a 4+ cubic foot box.
From what I seeing in WinISD the 12' Definimax 4012HO looks quite good in a 2.0 - 2.5 cubic foot box tuned to 40hz with a 2nd order highpass at 35hz. I'm showing 2 4" vents of 14" in length each keeping port velocity under 10 m/s. It can handle right around 150 watts before the driver gets into trouble, so since I plan on 100 watts max I will be fine.
The difference between 2 cubic feet and 2.5 from a SPL perspective is almost nill so I may go with the smaller box size just to save some space. I think I give up like 1db from 45hz down to 40hz.
Its still a bit pricey, but I dont mind hunting for a good bargain for a used driver, or waiting till Parts Express runs a deal on them.
If that's the route I go, once I get the driver in and the tweeter as well I will contact Wayne again to see if he's got a pre-configured passive crossover schematic for them already.
If not things will get tricky.
As far as going active..... thats not something I'm wanting to do at this point, though I can see the pro's of being able to tweak and build the crossover electronically for testing and tweaking on the fly, then building a REAL one once thats completed..... but thats hopefully not a route I have to go down.
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I figure this is a typo, but the Tempest actually goes down to 37hz which is what really caught my eye.
I'm looking hard at that driver or just using the 12" Definimax Wayne recommends.... I need to work on modeling the Delta Pro in WinISD to see what I can do with it and compare to the Definimax. The Delta Pro is a bit cheaper too so thats a nice factor in play as well.
In doing some quick fast dirty math, a box that is 20 wide x 13 deep x 20 tall and uses 3/4" wood has internal dimensions of 18.5 x 11.5 x 18.5. That equates to 2.2 cubic square feet. After subtracting the driver, ports and some small amount of bracing, that likely gets me RIGHT to 2.0 cubic square feet....
With the horn on top, that gives me a final dimension of 20 wide x 13 deep x 25.5 tall which is I think an acceptable size for what I need.
The Tempest box size, which likely needs tweaking since the waveguide and compression tweeter wont be there taking up internal space, is 14.5" wide x 26" tall x 13.5" deep, and I'd likely lay it on its side and try to tweak out some of that width so its closer to the dimensions of the horn sitting on top.
I have this feeling I am going to end up with a almost 2 foot wide x 2 foot tall x 1.5 foot speaker size lol.....
The only thing I'm not sure of is if I need to have the ports fire front or back, or if I can have them fire out the side. If they have to fire out the front or back I'm going to end up with a speaker thats quite deep unless I do a 90 degree turn internally with the port which I think your supposed to avoid.
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I was looking at the measurements of the 2ft box with the Delta Pro 12. Mid-band it's 95dB at 2.83V, which is impressive. If you take 95dB as reference, then it does play down to 40H, then rolls off fast. The bass bump above that will sound nice, but will be dependent on room gain. That's darn good for that size speaker. It's not small, but considering my old rig had 11 cu ft bass boxes (external), it's not a monster.
All the woofs mentioned will work well. If you have two amps, go with the MiniDSP. You can tweak the crossover parameters to fit your room much more persisly then messing with a passive. With those woofs and horn, going digital or SS on the woof and a small SET tube amp on the horn would be the nuts!!!
I was looking at the measurements of the 2ft box with the Delta Pro 12. Mid-band it's 95dB at 2.83V, which is impressive. If you take 95dB as reference, then it does play down to 40H, then rolls off fast. The bass bump above that will sound nice, but will be dependent on room gain. That's darn good for that size speaker. It's not small, but considering my old rig had 11 cu ft bass boxes (external), it's not a monster.
Yeah, I was hoping to get away with a 1.5- 1.75 cubic foot box, but then I'd have to go with a 8" driver and that would likely be hard to find a high sensitivity one that wasnt an arm and a leg that would work in that type of design. I'm ok with a 2 cubic foot box as thats the smallest I think I can really get into without getting a lot of rolloff as you drop below 60hz.
I'm totally fine with significant rolloff at 40hz as I plan to use my sub with these, but I'd like the "option" of running them as pure stereo speakers and still be able to get a fair amount of the normal frequency bandwidth from most music. I dont listen to pipe organs ever, though I enjoy a fair amount of dubstep and electronic music, which digs deeper than these will go, hence the sub addition.
I'm anticipating running a highpass around 35 on the Definimax, not sure about the Delta 10, I'd have to look at the graphs. If you have the WinISD file created already, anyway you could attach it here? I'm not so much good with inputting the numbers in the right sequence to get them to not error out.
Also since this setup will be 2m or less from you when listening, I doubt I will even get it above 90 db.
For my sim's I'm using 100 watts as the input signal as I dont anticipate using an amp with more than that anytime soon. I'm going to run them off my Anthem which is 100 wpc @ 8 ohm x 2 channels per spec, so thats why I choose 100 watts for modeling.
Yeah I thought of that, it just starts getting more complicated than I was hoping to go, but I am well aware of the benefits. With the MiniDSP as the crossover I would have to do a lot of work to get that right before running the Anthem ARC which I've found to do a STELLAR job at EQ. It would also basically make the amp channels in the Anthem a moot point as I couldn't use them.
Right now I JUST have the Anthem MRX-500 to work with so I could potentially use the marketed bi-amp feature to drive each driver independently, but that starts to get tricky I think....
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I failed to make it to his room before they packed up unfortunately.
I enjoyed JWM, The Black Hole, Stereo Clarity and Blowtorch's rooms immensely. Each for a different reason.
I also really liked Skips room (Audio Thesis). Douglas Connections room was pretty cool too and I enjoyed seeing all the bling he brought with him. And those small bookies in the GR Research room blew me away for a desktop setup. Those things were awesome.
There were a bunch of us from another forum floating around and most of us agreed we will be back next year.
If you listen to Dubstep and electronic music then a sub is a no brainier. In those genres, the subwoofer is used as a musical instrument. Listening to more "normal" music, a solid 40Hz will be plenty satisfactory.
I've attached 2 WinISD files zipped to get you started.The Delta 12A and a Dayton pro 12 that should play as deep in a slightly smaller box, but at ~3dB less efficient. I hope they have the driver parameters included.
I've attached 2 WinISD files zipped to get you started.The Delta 12A and a Dayton pro 12 that should play as deep in a slightly smaller box, but at ~3dB less efficient. I hope they have the driver parameters included.
They extract as .wid files not .wpr which are what all my other WinISD files show as.
Am I missing something?
Weird, I'm running it on Windows 10 with no problems...
Try this version: http://www.linearteam.org/download/winisd-07x.exe
Try this version: http://www.linearteam.org/download/winisd-07x.exe
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