I have found quite a bit on tractrix horns and want to build one for a full range driver in the approximately 4" size. It will be supported by helper woofers so base extension is not my primary goal. 100Hz - 150Hz is low enough.
Actually, the primary goal is to build the horn. It is a lot of trouble when a rectangle box of the right dimensions or an open baffle work just fine in my experience. I have never built one and have some ideas about using wood segments to build the horn up. I have seen lovely looking horns made of everything from concrete to gossamer paper. But I like to work the wood.
Because it will be a lot of work, I would appreciate recommendations and horn dimensions from those that are proven and already successful. I have played with some calculation models but I am slow to pull the trigger on a model I have not heard.
Thank you in advance.
Actually, the primary goal is to build the horn. It is a lot of trouble when a rectangle box of the right dimensions or an open baffle work just fine in my experience. I have never built one and have some ideas about using wood segments to build the horn up. I have seen lovely looking horns made of everything from concrete to gossamer paper. But I like to work the wood.
Because it will be a lot of work, I would appreciate recommendations and horn dimensions from those that are proven and already successful. I have played with some calculation models but I am slow to pull the trigger on a model I have not heard.
Thank you in advance.
Would this be a front horn? Tractrix is not particularly useful for back horns AFAIK, where exponential or hyperbolic is better. For a front horn, to get any kind of usable bandwidth, you need a driver with rising response and a true ~150Hz horn would likely kill the upper-midrange and HF output of even that. Even if you can manage a decade of ~flat bandwidth, this only brings you to 1500Hz.
IMO, best would be to find a driver with on-axis rising response well into the treble and go for a ~400-500Hz front horn. Even then, a super-tweeter might be required.
IMO, best would be to find a driver with on-axis rising response well into the treble and go for a ~400-500Hz front horn. Even then, a super-tweeter might be required.
With this particular driver, you're defeating the reason for using a horn, so might as well just make a simple two flare conic wave guide like DSL uses for its various Unity/Synergy concepts and not have the tractrix's variable beaming added to the driver's natural rising on axis response.
GM
GM
+1 on what GM said.
I've build such a 2-flare conical a few years back. Still not a free lunch, as all horns are bandpass devices. It was quite large, but perhaps not enough to go down to 150Hz. Using the old Fostex FF125K, which has about as much a rising response as any driver in its size class available today, I still had some loss in the upper treble and above. A 150Hz equivalent would only be worse in that regard, especially with a flatter response driver.
I've build such a 2-flare conical a few years back. Still not a free lunch, as all horns are bandpass devices. It was quite large, but perhaps not enough to go down to 150Hz. Using the old Fostex FF125K, which has about as much a rising response as any driver in its size class available today, I still had some loss in the upper treble and above. A 150Hz equivalent would only be worse in that regard, especially with a flatter response driver.
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I really appreciate the objective perspectives shared. What started me down this path was seeing more and more of these Dr. Seuss looking horns at uber high end audio shows on-line. I was surprised to see Lowthers driving them. I had only seen and heard horns with compression drivers in the 2" range. Because I have FR drivers unemployed at present, and because I want to inaugurate my recent move and setting up shop with a way-cool wood working project, this idea asserted itself. Perhaps I don't understand what these Oris and other horns are about. Then there are the sheet goods made by Appleply that are about the purtiest plywood I have seen. That and a construction I wanted to try out and there are some huge laminated ply flower horns I saw in my future. I likely need to move on to compression drivers if its a horn.
But can someone enlighten me on the obvious presence of full range drivers in horn loaded enclosures like the Oris? Is this just a novelty that takes a load of crossover sonic surgery to tame?
But can someone enlighten me on the obvious presence of full range drivers in horn loaded enclosures like the Oris? Is this just a novelty that takes a load of crossover sonic surgery to tame?
Lowther drivers are technically horn drivers due to their stepped HF response. IOW, looking at XRK's response plot, a horn driver would have a stepped up HF response that would blend in with the horn's HF falling response to make for an on axis ~flat response out to whatever the driver's HF mass corner is, i.e. he would not have to EQ it flat to a lower efficiency.
Look at some Oris horns with other brand drivers that don't have this stepped up response and the 'horn' is actually a very fast expanding one that makes it basically a WG and since conic has the least impact on a driver's output, the best overall for high SQ pattern control.
Yes, Appleply, Baltic Birch and marine grade are the wood materials of choice for durability and high SQ designs.
GM
Look at some Oris horns with other brand drivers that don't have this stepped up response and the 'horn' is actually a very fast expanding one that makes it basically a WG and since conic has the least impact on a driver's output, the best overall for high SQ pattern control.
Yes, Appleply, Baltic Birch and marine grade are the wood materials of choice for durability and high SQ designs.
GM
This all makes total sense. And, I really appreciate the reality testing from y'all. I clearly need to learn more about horns. But I am a hands on type of learner. And, I am mathematically incontinent. I like to build things. I enjoy a dumb Neanderthal block diagram recognition of the engineering issues. I follow plans and have a garage wood working shop. But truth be known, there have been plenty of bonfires of audio vanity cab's that did not sound right, and they are no more. Carbon unto carbon.
I have relocated to the low country of GA. There is no "hifi" community I can find in Savannah. There were a ton of bottle heads and speaker enthusiasts in E.TN. But there is a great resource here, Stereo Doctor, that fixed a Golden Tubes amp of mine that did not make the move. I am organizing years of storage and both working and non working systems at present.
This place is ok, but not home yet. My main room is 13' x 27' with only 8ft ceilings. The end of the room, where the speakers are placed, is lined with book cases. It is open on the left and the right to other large rooms. The other end of this "not so great room" is a dinning table and, at about 12' from the speakers, is the listening spot/captain's bridge to the sound controls. The speakers are 3' away from any wall, in front of the book shelves, so I can't take advantage of corners or walls. I have never had a room like this.
But I want to start playing with horns and maybe eventually build some horns. It's new to me and I want to make something other than boxes with mazes inside of them for a change. I remember being in my early 20's and hearing Klipsch corner horns. It was unlike anything I had ever heard. I was hooked on hifi. But I have been down the road of multi-driven systems, full range systems, and electrostatic systems since then. I want to play with some horns in my pipe years. Its not a big gamble. I have all kinds of speakers and amps that will continue to work great as this develops.
I still listen primarily to FR back loaded horns and reflex cabs. I fire up the KEF B139/B110/T52's for the occasional live Hendrix rock concert or Mahler symphony.
These sorts of requests often just die on the vine of DIYAudio and thats ok. It is boring and can appear lazy or entitled. Someone gushes about wanting the "best" system or quips "price is no object." LOL.
But, seriously, what recommendations would you kind and experienced people make for horn systems for this sized room? Would an Altec 811b convert me or would it be an 800 pound canary in such a room. I wanted to build some horns but now I think I need to just buy some used vintage horns that have proven successful over the years and see how they work.
Thanks Again for the patience and the support.
I have relocated to the low country of GA. There is no "hifi" community I can find in Savannah. There were a ton of bottle heads and speaker enthusiasts in E.TN. But there is a great resource here, Stereo Doctor, that fixed a Golden Tubes amp of mine that did not make the move. I am organizing years of storage and both working and non working systems at present.
This place is ok, but not home yet. My main room is 13' x 27' with only 8ft ceilings. The end of the room, where the speakers are placed, is lined with book cases. It is open on the left and the right to other large rooms. The other end of this "not so great room" is a dinning table and, at about 12' from the speakers, is the listening spot/captain's bridge to the sound controls. The speakers are 3' away from any wall, in front of the book shelves, so I can't take advantage of corners or walls. I have never had a room like this.
But I want to start playing with horns and maybe eventually build some horns. It's new to me and I want to make something other than boxes with mazes inside of them for a change. I remember being in my early 20's and hearing Klipsch corner horns. It was unlike anything I had ever heard. I was hooked on hifi. But I have been down the road of multi-driven systems, full range systems, and electrostatic systems since then. I want to play with some horns in my pipe years. Its not a big gamble. I have all kinds of speakers and amps that will continue to work great as this develops.
I still listen primarily to FR back loaded horns and reflex cabs. I fire up the KEF B139/B110/T52's for the occasional live Hendrix rock concert or Mahler symphony.
These sorts of requests often just die on the vine of DIYAudio and thats ok. It is boring and can appear lazy or entitled. Someone gushes about wanting the "best" system or quips "price is no object." LOL.
But, seriously, what recommendations would you kind and experienced people make for horn systems for this sized room? Would an Altec 811b convert me or would it be an 800 pound canary in such a room. I wanted to build some horns but now I think I need to just buy some used vintage horns that have proven successful over the years and see how they work.
Thanks Again for the patience and the support.
If you can find a Bruce Edgar tractrix used get it. Put a PRV 5MR450NDY in it for 400Hz to 15kHz at 105dB sensitivity. Then find a used University Classic horn and that will take you from 60Hz to 500Hz using a 15in pro audio 100dB woofer that is now probably 105dB sensitive. Drive them with some 50 watt TPA3116 class D amps and use a miniDSP for XO, EQ and time alignment. This will play classical as well as rock with guitars and drums very well. Can be very loud too as you are indoors - won't need more than 10 watts or so.
Sage advise. I have been reading articles by Edgar and skimming over the Lansing Heritage forum. It is like dropping in on a Packard car enthusiast weekend. I had always considered these horns the province of theaters and ball rooms in big hotels. I need to figure out what works in the relative near field of 10' in such a modest room.
Thanx
Thanx
When I was 18 I had DIY Altec A7-500s in a 10 x 10 ft bedroom and by 25 a trio of A4/805s in a ~26 x 46 ft 'great' room, so about the same, acoustic scale wise and nobody seemed to think either was overkill/too large once they heard their favorite music through them with a clarity and life-like presence like never before and probably since for one reason or another.
Speaker design theory says to scale them to the room/listening distance though, so 12 ft back either a 'small' studio monitor with a ~800-1200 Hz XO with one or two 12" or single 15" will work and since you mentioned the 811, a variation of Altec's M19 with GPA components and modified XO in a MLTL alignment would be my recommendation if the parts cost is OK. Several have been done and all have been very pleased.
GM
Speaker design theory says to scale them to the room/listening distance though, so 12 ft back either a 'small' studio monitor with a ~800-1200 Hz XO with one or two 12" or single 15" will work and since you mentioned the 811, a variation of Altec's M19 with GPA components and modified XO in a MLTL alignment would be my recommendation if the parts cost is OK. Several have been done and all have been very pleased.
GM
Large and sensitive speakers can be pretty great in comparatively small rooms, where they'll render large-scale music with no effort. As with everything, there are tradeoffs and associated issues.
Personally, I like compression drivers and constant directivity waveguides for ~1kHz+. If you want a cone driver, the PRV 5" seems like it could be decent in an appropriately designed Tractrix horn; the 200Hz-1kHz rising response and later 5kHz+ raised shelf should help to make for an extended response, but a super-tweeter is likely to be required IMO, both for extension and dispersion.
The only Tractrix I've experienced is an 11-segment 700Hz petal horn I've built a couple of years back for 1" compression driver. Sounded pretty good playing ~800-900Hz and up with the old Emilar EC-175. A bit of EQ was required. Much different than my usual constant-directivity speakers. Gets beamy fast, but takes the room out of the equation, which can be both a curse and blessing. Heh, no free lunches!
Personally, I like compression drivers and constant directivity waveguides for ~1kHz+. If you want a cone driver, the PRV 5" seems like it could be decent in an appropriately designed Tractrix horn; the 200Hz-1kHz rising response and later 5kHz+ raised shelf should help to make for an extended response, but a super-tweeter is likely to be required IMO, both for extension and dispersion.
The only Tractrix I've experienced is an 11-segment 700Hz petal horn I've built a couple of years back for 1" compression driver. Sounded pretty good playing ~800-900Hz and up with the old Emilar EC-175. A bit of EQ was required. Much different than my usual constant-directivity speakers. Gets beamy fast, but takes the room out of the equation, which can be both a curse and blessing. Heh, no free lunches!
Review
I found the Westend MLTL cab you designed for the 416-8B woofer, and I have a friend who is willing to sell a paiar me at reasonable cost. I have not seen a sketch or plans for the salsa. I have seen the wonderful information, put on the web. But is is now 8mil from any reliable transportation requirments.
I am getting the hang of searching these forums. There is a lot that is repetitive in the questions and answers. I now understand why some threads die on the vine.
There are a dozen threads on the 416 in an MLTL and half are "GM" designs. The ones on HostBoard and by westend are best.
In terms of forum protocol do I ask questions here about the "Westend" GM 416-8B/MLTL or do I start a new thread? I can't imagine the number of PM's you must get, and you are not accepting them off of this board.
For a big project Peach State Lumber was go to, but I did not have the truck. I am still trying to source quality sheet goods here in the coastal empire.
Suggestions welcome. Happy Memorial Day.
There are a dozen threads on the 416 in an MLTL and half are "GM" designs. The ones on HostBoard and by westend are best.
In terms of forum protocol do I ask questions here about the "Westend" GM 416-8B/MLTL or do I start a new thread? I can't imagine the number of PM's you must get, and you are not accepting them off of this board.
For a big project Peach State Lumber was go to, but I did not have the truck. I am still trying to source quality sheet goods here in the coastal empire.
Suggestions welcome. Happy Memorial Day.
I'm running / testing multiple horns for exactly this, using a 4" pro driver. In a simple conical horn with roundover to a 60cm wide baffle, I get similar response to what x posted for his horn - a shelf of boosted output from 300-3000Hz, with lower output up to 15kHz. (i get dead flat response down low, and peakier up high, but overall very similar, and possibly mostly different due to measuring differences). A bigger horn (80cm wide and 40cm high) went lower, but not to 150Hz, so I think you might have to settle for a 300ish low end on the horn if you want something reasonably sized.
Massive equalization works well, but something else that seems promising is basic crossover on the horn and a fill / scatter tweeter. That is: an efficient tweeter firing up and backwards at the roof so that the HF fill is dispersed and delayed.
The Azura Horn site is the only place I've seen a Lowther on front horn measured. It may have many excellent properties, but it is not flat across any part of its range.
Massive equalization works well, but something else that seems promising is basic crossover on the horn and a fill / scatter tweeter. That is: an efficient tweeter firing up and backwards at the roof so that the HF fill is dispersed and delayed.
The Azura Horn site is the only place I've seen a Lowther on front horn measured. It may have many excellent properties, but it is not flat across any part of its range.
Hmm, I can only recall two Altec loaded MLTLs ATM that's been posted that I didn't 'do' in some way or other and dozens more of them alone in private back when I had the time, tools to quickly do so, but for now I've neither and why I was forced to block my forum PMs.
Really, between Hornresp, AkAbak, MJK's MathCad, AJ Horn and recently, Leonard Audio's software, anyone can design their own that can theoretically be superior to my way, though it remains to be seen/heard if audibly so, and Horresp can only sim the vent at the extreme bottom.
Regardless, if you plan on building westend's 811/416 alignment and have Qs about it, then post them there; otherwise just reference it here to discuss and since you're wanting to build a multi-way, please get a moderator to move it.
Peach State Lumber 'coastal'? I thought it was only in Kennesaw, Ga.
GM
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