The Aethers: budget Dipoles from Iowa DIY 2007

[Undefinition]

If anyone's interested in more details about this design (which somehow managed to beat out some fantastic budget designs at Iowa 2007), the writeup is finished. You can find it here:

https://sites.google.com/site/undefinition/dipole-and-open-baffle/diy-aethers

Quick overview:
completely passive, parallel xover
Vented bass, open-back mids
Sensitivity: about 84 dB
T: Seas 27 TDFC
M: Vifa P13WG (4 ohm, in series)
W: Dayton 8" DVC sub
cost: about $250 in drivers and electronics

Any questions, email, or post here or on PE and I'll get back to you as soon as I can. Enjoy!

-Paul Carmody

[---k---]

Paul,

Thanks for posting. That is a great write up.

I thought they sounded pretty good in Iowa (except you had the same bass problem that Dan, Jim, and a few others had. ). I'm looking forward to hooking up sometime and getting more time to explore the world of Open Back speakers.

[JasonB]

Paul,

I have been looking for a low cost fully passive dipole for some time now. I realize the woofers are a conventional monopole setup but this may be the closest I will come in this price range, I have seen your writeup and it's great. All I need to know at this point in time is either the DC resistance or the wire gauge and core type of the inductors used in your crossover, even better yet you could just tell me where you got them.

Thanks,

Jason

[Undefinition]

Hi there.

The inductors were:
.47 mH (15 Ga air core)
4.7 mH (15 Ga Jantzen P core)

I'm pretty sure you could move up to 18 Ga for the air core and save a few bucks. The bit of extra resistance in the inductor wouldn't hurt, because I tend to like mids voiced almost "hot," and most ears might like a bit more padding in that area, especially for extended listening.

The P core inductor seems very nice. But I don't have an iron core in that value to compare it to to see if it actually makes any difference. I took a gamble on this project, and decided to try them.

By the way, the caps are all non-polar electrolytic, except the 5.1 uF on the tweeter, which are Dayton polys. Dis me all you want! 83 uF in polys or film is 'spensive! You want to sponsor a version with better caps, be my guest; I'd be curious to hear the difference.

Maybe I ought to just make a BOM Gimme a day or two, and I'll get that done.

Paul

[Coconutout]

Paul,

Thanks for posting. That is a great write up.

I thought they sounded pretty good in Iowa (except you had the same bass problem that Dan, Jim, and a few others had. ). I'm looking forward to hooking up sometime and getting more time to explore the world of Open Back speakers.

by jim would you be referring to jim holtz's statements? what was the problem with statement's bass?

[Hdale85]

They said it sounded boomy in the theater. Said it may have been due to the hallow stage floor.

[Sefferdog]

by jim would you be referring to jim holtz's statements? what was the problem with statement's bass?

It was actually the Mini Statements that had a slight problem, but from the looks of things it must not have been too bad. They won the midrange class! 8O

[dlneubec]

My HOSS plate amps were set at too high a volume for the theater, even though they were perfect in my 15'x20' room at home. The Mini Statements had a pretty strong boom. Paul's Aethers may have been a little strong in the bass also. Actually, it was rather astounding how much bass all the speakers had, even the RS150/BGNeo3PDR MT.

I believe it probably had to do with a couple things. First, there was a total lack of the bass cancellation (due to room modes, etc.) in that room that we normally see in our smaller rooms. Also, those that had the most enhancment in the bass were speakers with one bass driver or a port near the floor. That may have had something to do with the stage, I don't know, but based on how much stronger the bass in the HOSS was than it is in my home, my guess is that the Aethers and the Mini Statements are just perfect in a typical residential setting.

[Coconutout]

It was actually the Mini Statements that had a slight problem, but from the looks of things it must not have been too bad. They won the midrange class! 8O

haha. sweet. high-five!

[Undefinition]

I'm a man of my word. Proof that I DID build these for under $300. Actually, I paid $10 less apiece for the tweeters, as they were clearance versions that had little black grilles. Also, I have no idea what the L-pads SHOULD cost, since I pulled them off an old pair of Pioneers. You're free to use resistors, but get a few values between 1.5 and 4 ohms, and voice to taste (and room).

-Paul

[chasw98]

By the way, the caps are all non-polar electrolytic, except the 5.1 uF on the tweeter, which are Dayton polys. Dis me all you want! 83 uF in polys or film is 'spensive! You want to sponsor a version with better caps, be my guest; I'd be curious to hear the difference.

I'm a man of my word. Proof that I DID build these for under $300. Actually, I paid $10 less apiece for the tweeters, as they were clearance versions that had little black grilles. Also, I have no idea what the L-pads SHOULD cost, since I pulled them off an old pair of Pioneers. You're free to use resistors, but get a few values between 1.5 and 4 ohms, and voice to taste (and room).

-Paul

I am so tempted to send you a set of capacitors for you to try out on a single speaker for comparison. You built these speakers for the price I just paid for capacitors alone on my latest project. Maybe, just maybe......

Chuck

[ThomasW]

Also, I have no idea what the L-pads SHOULD cost, since I pulled them off an old pair of Pioneers

L-pads need to the the same impedance as the tweeter, so 8 ohm for an 8 ohm tweeter, 4 ohm for a 4 ohm tweeter. If they aren't matched there are problems...

[Undefinition]

I am so tempted to send you a set of capacitors for you to try out on a single speaker for comparison. You built these speakers for the price I just paid for capacitors alone on my latest project. Maybe, just maybe......

Chuck

Yeah, it would definitely be interesting. You know, sometimes we spend so much on "quality" components, and how often do we really check to see if the extra money was worth it?

[Undefinition]

L-pads need to the the same impedance as the tweeter, so 8 ohm for an 8 ohm tweeter, 4 ohm for a 4 ohm tweeter. If they aren't matched there are problems...

What kind of problems? Just curious.

Also, the tweeter (and mids) are 6 Ohm loads. And they don't make 6 Ohm L-Pads. Keep in mind also that this whole project began with me just looking around the house for something to voice with. They sounded OK, and the values modeled without problems in PCD.

[augerpro]

I thought I read that listeners at the diy meet would list the strengths/weaknesses of each project for owner to take with them? What do you think are the strengths and weaknesses of this design? Why did so many people like it?

[Undefinition]

I thought I read that listeners at the diy meet would list the strengths/weaknesses of each project for owner to take with them? What do you think are the strengths and weaknesses of this design? Why did so many people like it?

I'm not sure if you're asking me here... or if I'm even the right one to answer this question, as I'm biased. :W

In my opinion, the biggest weaknesses of the Aethers are technical. They do have a dip down to 3 and 4 Ohms in the bass region, due to the Dayton DVC sub. Also, they employ a 1st order crossover almost all around, and I believe that topology has a lot more naysayers than it does supporters. The other weakness of the design is simply the poly mids. They're very easy to work with, but they're not the most detailed drivers.

The strengths of this design, I believe, lie in the fact that the drivers are all operating in "comfortable" territory, and are not being squeezed or beaten by a complex crossover. They're good drivers to begin with, so as long as you let them "sing" the way they were meant to, they are likely to produce a good system overall. I also believe that the other strength of the Aethers is that they are tuned to be very musical. I have years of experience as a performer, arranger, and composer, as well as pro audio experience, so I feel like I know what certain things should sound like. The Aethers were tuned from the midrange out. I wanted human voices and acoustic guitars to literally sound like they were in the room. I wanted snare drums, clarinets, and violas to truly sound like their real-life versions, not squashed into a mix like they normally are. In the low end, the bass has a nice solid attack because the DVC cone is surprisingly stiff, and I worked for a long time to get the vented bass to click. So when I finally voiced the tweeter, I was really only looking to add air and high-end detail to instruments... the important musical information (to me) was below 3K. If things weren't clear and balanced below 3K, things wouldn't have sounded as realistic. Obviously, the final factor that was the big strength of the Aethers was the the dipole mids radiated into the room, and--again--created a more realistic soundstage.

I've heard some great box speakers at DIY events, and built other people's designs, and many of them are far better than anything I could design. So I wasn't even trying to compete with boxed speakers with this project, or create the perfect technical design. I was trying to re-create real-life music. In order to not sound pompous like some B*se ad, I'll shut up now.

[Andy_G]

Also, they employ a 1st order crossover almost all around, and I believe that topology has a lot more naysayers than it does supporters. The other weakness of the design is simply the poly mids. They're very easy to work with, but they're not the most detailed drivers.

I'm going to disagree with you on either of these being problems.

Both, in combination help, produce a much more natural sound than over controlled and filtered harder metal cones. Small poly cones do not lack detail, except compared to the over the top analytical sound of metal cones, which are often harsh and un-natural unless hammered into submission by a myriad of cross-over or correction components.

just my opinion :rant:

[Jim Holtz]

I'm going to disagree with you on either of these being problems.

Both, in combination help, produce a much more natural sound than over controlled and filtered harder metal cones. Small poly cones do not lack detail, except compared to the over the top analytical sound of metal cones, which are often harsh and un-natural unless hammered into submission by a myriad of cross-over or correction components.

just my opinion :rant:

Andy, Andy, Andy!

You are in the land of hard cone mania, of which I'm a proud member, and you're kicking dirt on our beloved cones. :rofl: Just kidding of course but honestly, the direction here is for accuracy of music reproduction with minimal coloration so poly and most paper drivers can't cut it.

I'll have to disagree with you in that a low distortion metal cone driver with a well designed crossover will be smooth, clean, detailed and extremely musical. Try a TB W4-1337SA and you'll see what I mean. No 1st order crossovers but 2nd will work fine.

Good to hear from you!

Jim

[Jim Holtz]

I thought I read that listeners at the diy meet would list the strengths/weaknesses of each project for owner to take with them? What do you think are the strengths and weaknesses of this design? Why did so many people like it?

Hi Brandon,

Since I was one of the group scoring them, what I liked best was the open sound stage and the top end. Seas tweeters are a favorite of mine. They also did well on vocals.

There were some very nice speakers in the Budget group this year but the di-pole sound stage nosed out the rest. I think the sound stage was the single feature that lingered in peoples minds when scoring.

Jim

[---k---]

I thought I read that listeners at the diy meet would list the strengths/weaknesses of each project for owner to take with them? What do you think are the strengths and weaknesses of this design? Why did so many people like it?

I heard them. I thought they had a good open, natural sound. As I've expressed a couple of times, I would like to hear them more. But, and this isn't to take away from Paul, they were a Budget speaker. They weren't the most detailed or distortion free speaker of the day. They were just a good, solid, open back design that is uncommon in the Budget class.

[Hdale85]

Anyway you can do a better sketchup of the enclosure deminsions? I'm just having a hard time following them.

[Undefinition]

Anyway you can do a better sketchup of the enclosure deminsions? I'm just having a hard time following them.

I can make a cut list in sketchUp. it will take me a few days, but I'll do it for the love of DIY.

For the time being, here is a very verbal description of the dimensions:
The U-frame cabinet is 10.5 x 4.5 x 18
The bass bin is 10.5 x 13 at the top, and 10.5 x 16 at the bottom. It is exactly 24 inches high. Note that the front baffle of the bass bin is 1.5" thick. This makes for an internal volume of about 1.5 cu ft.
The mids are centered horizontally, and placed in 4" from the top and bottom of the top cabinet
The tweeter is centered vertically (in the top cabinet), and offset somewhat--making it about 4.25" from the edge of the cabinet. I think I may have actually used the golden ratio to figure this out ;-)
The woofer is centered on the baffle horizontally, and placed about 9.5 inches up from the ground.
The vent is on the back. I used a 2" inch piece of PVC pipe, about 5" long, located about 4 or 5 inches from the top of the cabinet.
The bass bin has about 3 horizontal braces, about 3" wide, placed at "irregular" spacing inside the cabinet. The walls are lined with a layer of carpet padding, and loosely filled with polyfil to about half way up the cabinet. I'm sure egg crate foam would make a good wall liner--and you may actually be able to get away with no wall lining at all, just by trying out different amounts of stuffing.
Also of note: in my house I often keep a layer of quilt batting (it comes in a roll at Wal Mart) jammed behind the U-frame cabinet. This helps tame the backwave of the mids *just a bit. Depending on the music, though, I sometimes remove it. At Iowa, I did not use the batting at all, because the room was enormous, and the speakers just sang.

[Andy_G]

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[Andy_G]

Anyway you can do a better sketchup of the enclosure deminsions? I'm just having a hard time following them.

I'd try to switch to a bass driver without the yuk at 1k. That way you are not forced to compromise the sound by using a parallel cross-over..

(remember it needs to have a few extra dB sens for BSC purposes) good hunting ! :roll:

gees , I'm in a mood, aren't I !! :rofl:

[Hdale85]

Not sure I'll be building these...I have a brother in law that wants to build a set of speakers though and these definitely fit the budget.

[Andy_G]

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[Hdale85]

Yes I know He has a large bedroom with very little in it so wouldn't be a problem.

[Undefinition]

Yes I know He has a large bedroom with very little in it so wouldn't be a problem.

Wow! These would be crazy in a bedroom! They're definitely full-range. last night I was shaking the house with them with very little effort. That said, I wouldn't mind just drifting off as I got lost in the soundstage. Plus, even though I have a flat line through the midrange (no dip), they're not fatiguing to listen to--my guess would be the cone type, but I'm trying not to start a war here. Tuned properly to the room, they're nice and dynamic, and you will hear a lot of details from recordings.

[Andy_G]

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[---k---]

Let the war begin!

But, yes you are probably right. Those poly cones and first order crossovers mush up the music so much that it pretty much impossible to get fatigued from.

Metal cones need a lot more attention to prevent fatigue. You won't get fatigued from listening to mine.

Dougie, you better make sure you understand what you're getting and the tradeoffs before you spend cash. If you compare these to the Lineups your building, your brother may be very disappointed in the amount of detail and accuracy he gets. However, on the flipside you get all the benefits of an open back speaker with a subwoofer and YOU may be disappointed. Again, not to take away from Paul, but in this price range, there are a lot of tradeoffs that you must understand.

[Hdale85]

Yeah I know. I'm not sure he's ears are trained well enough to really notice a lot of difference. We're looking for something cheaper for his first setup. Currently he has a set of 10 dollar computer speakers and thinks they are great....so I have to "save" him I found a new amp kit I think I'm going to try out. Uses a chip (LM4702) for the driver and has fets for outputs. I'm going to build one my self and if I decide its good its what we'll probably use for his system. Only bad thing is their kits come with some cheaper parts but no big deal I can always tune and tweak it later.

[Andy_G]

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[---k---]

You forgot the smileys. :roll:

[ThomasW]

it is nice to be able to listen to the MUSIC not the cross-over components trying to control the rattles of the metal cones....I guess k's mushy experience comes from trying to use 50 or so x-o components on a poly cone in a tight cabinet.. ie, lack of experience.

Take this kind of blather elsewhere, it's not welcome here.

[---k---]

I probably started it. I'm sorry. I see there is a smiley there now, I didn't see it earlier. But, you're right. Best to move on.

[Andy_G]

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[ThomasW]

Failed to see any humor in the snipping.

If you have something constructive to post that's always welcome.

[Dennis H]

It all started with some trash talk leading up to Iowa. The mods probably should have nipped it then but now is as good a time as any. On the internet, it's really hard to tell the difference between friendly trash talk like you'd do with your buds and serious insults. Andy and Ryan (and any others involved) are all good guys and I trust that they didn't mean anything unfriendly.

[tktran]

I have been hanging around HTGuide long enough to know that many of the regulars here are fans of hard cone drivers. Just take a look at the Misson Accomplished section. It is the home hard cones and steep filters.
Any hint of an impedance wiggle or delayed energy-time curves and the crowd run for the hills.

There are many ways to skin a cat, but I think we all agree that loudspeaker design is full of compromises. It depends on what one's willing to accept.

Remember Thomas, you are free to make fun of Andy for his serial crossover fanaticism and "Who-needs-measurements?" approach to crossover design.

I know I do.



There is a post over at DIYAudio where the moderator hopped in exclaiming "90 dB is high sensitivity?" (in reference to a SEAS ER18RNX/27TDFC MTM) and goes on to suggest Fostex 6" full range drivers in 15L cabinets....

[MuaDibb]

It is the home hard cones and steep filters.
Any hint of an impedance wiggle or delayed energy-time curves and the crowd run for the hills.

OMG! You mean this is one of those "hard cone" sites? Well my mother was right. She said it starts with a an innocent "poly" here or there, then its on to the hard cones, and before you know it your buying ceramics and living on the street. Mommeeeeeeeee, save me from the speaker dealers!

[---k---]

I started it. It was a joke, but can get out of hand quickly. My fault. I apologize. Lets get back to talking about Paul's great budget open baffle speakers.

Paul, when you going to have CJD and me over to your place for a listen?

[Undefinition]

Paul, when you going to have CJD and me over to your place for a listen?

I look forward to that. It'll be sometime after December, as I'm getting married next month. It'll be fun. Maybe Chris will have another design by then.

[---k---]

You're letting a wedding come before a bunch of guys from the internet with speakers? Sheeshhhh. So it begins.

[philip_g]

I kind of dig it.
if I build them thomas, do you want to listen to them? lol.

[Andy_G]

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