So for those that are seriously thinking about building your own DIY full-range Multiple Entry Horn (MEH), also called "Synergies™", some questions:
1) What common compression driver(s) and woofers would you most want to use (brand and model) in a kit?
Remember that the compression drivers must cover a wide operating band, so 2" compression drivers are typically simpler and also in the $140-$240(US) range. These will replace midrange drivers that are difficult to integrate and are problematic when it comes to finding real estate on the horn throat area between the compression driver and the woofers. That way you avoid more than 2/3rds of the problems encountered with multiple entry horns.
Woofers need to have medium Qts values (0.6, etc.) and relatively low Fs to work well as horn-loaded woofers.
2) What is the lowest crossing frequency (i.e., "fc") that you would want out of the loudspeaker?
Typical values are in the range of 100, 50, and 30 Hz for "full-range" horns.
3) What maximum size would you be willing to build/buy for your listening environment?
The size of a Klipsch La Scala? Smaller? How small? How much low end would you be willing to give up to have a small size? Are these only going to be stereo pairs? Three across the front? Or surrounds, too? Elevation (Atmos)?
4) How much would you realistically be willing to spend per loudspeaker to make them from a kit?
5) Would you be willing to use an active crossover instead of passive?
1) What common compression driver(s) and woofers would you most want to use (brand and model) in a kit?
Remember that the compression drivers must cover a wide operating band, so 2" compression drivers are typically simpler and also in the $140-$240(US) range. These will replace midrange drivers that are difficult to integrate and are problematic when it comes to finding real estate on the horn throat area between the compression driver and the woofers. That way you avoid more than 2/3rds of the problems encountered with multiple entry horns.
Woofers need to have medium Qts values (0.6, etc.) and relatively low Fs to work well as horn-loaded woofers.
2) What is the lowest crossing frequency (i.e., "fc") that you would want out of the loudspeaker?
Typical values are in the range of 100, 50, and 30 Hz for "full-range" horns.
3) What maximum size would you be willing to build/buy for your listening environment?
The size of a Klipsch La Scala? Smaller? How small? How much low end would you be willing to give up to have a small size? Are these only going to be stereo pairs? Three across the front? Or surrounds, too? Elevation (Atmos)?
4) How much would you realistically be willing to spend per loudspeaker to make them from a kit?
5) Would you be willing to use an active crossover instead of passive?
A 1" compression driver is the most popular size for Synergy Horns.
The choice of midrange will determine everything else.
If I were making a kit, I would base it on Bill Waslo's "Small Syns" project:
Tymphany compression driver $30
Celestion midrange $30
Faital midbasses $??
If someone had space for something larger, I'd replace the midbasses with the Cerwin Vega twelves that Apex Jr sells. $25
If you want to make it smaller, you can make Bill's design smaller by replacing the celestion mid with a Dayton RS52
The choice of midrange will determine everything else.
If I were making a kit, I would base it on Bill Waslo's "Small Syns" project:
Tymphany compression driver $30
Celestion midrange $30
Faital midbasses $??
If someone had space for something larger, I'd replace the midbasses with the Cerwin Vega twelves that Apex Jr sells. $25
If you want to make it smaller, you can make Bill's design smaller by replacing the celestion mid with a Dayton RS52
If you want this thread to be a rehash of 3-way MEH kit threads, then I suppose you could simply answer with that kind of thinking. However, that's not what I'm planning. I also can't plan anything until I get some data from those that want a full-range MEH kit (i.e., not those that intend only to build their own MEH designs without kit help).
I see a lot of complaints about the lack of full range multiple entry horn (MEH) kits. I really like what Bill has done and have thanked him profusely, and the ease of using Hornresp to model relative to using ABEC or other BEM/lumped codes, the fact remains that there really aren't any full-range MEH kits (or any "MEH kits" for that matter).
The Sound Physics Labs Unity patent is more than 2 years out of expiration--which by legal means makes it unable to be reinstated, i.e., the IP is free and clear according to the USPTO.
I see a lot of "half full-range" MEH creations on this forum, but I've found that they are just like Lowthers and other "full range drivers"--that aren't actually full range. You have to integrate a woofer into them at some midrange frequency. Typical vented box direct radiating woofers don't sound very good to my ears. YMMV.
I've been using 1.4" and 2" compression drivers on K-402 two-way Jubilees for almost 10 years now--crossed at 400 Hz and extending up to 16-18 kHz, whose performance is spectacular, IME.
I've also built a true full-range MEH based on the K-402 horn that uses two 15" woofers (I used the Danley SH-96 design as a launchpad for thinking about the design). Unfortunately the SH-96 costs more than $8000US each. You probably don't need 11 drivers in your MEHs in your home listening room, too.
The results of the K-402-MEH--well, you'll have to hear it for yourself. You can bound its performance by reading Jubilee reviews and adding point source capability and superior midbass coverage to those reviews, and also being about 1/3 the size of the Jubilee envelope. For me, using larger 1.4"-2" compression drivers solve problems, including eliminating a set of fairly complex and extremely audible higher frequency crossover filters. The larger 1.4" or 2" compression drivers have become more economical to get very good performance over the past 10 years.
You can continue to use 1" midrange drivers and midrange cone drivers in a 3-way. No one is stopping you. Continue on, please... This thread is about a prospective full-range MEH kit. Elimination of the "real estate problem" in shoehorning midrange drivers between the apex compression driver and the woofers is a big deal. It's okay for the full DIY crowd (including designing their own using spreadsheets and Hornresp) to go 3-way to decrease driver costs (but perhaps not crossover costs), while the kit DIY community is apparently still waiting for a simpler solution.
But you can answer in any way that you wish (short of feeding trolls, of course)...
Chris A
I see a lot of complaints about the lack of full range multiple entry horn (MEH) kits. I really like what Bill has done and have thanked him profusely, and the ease of using Hornresp to model relative to using ABEC or other BEM/lumped codes, the fact remains that there really aren't any full-range MEH kits (or any "MEH kits" for that matter).
The Sound Physics Labs Unity patent is more than 2 years out of expiration--which by legal means makes it unable to be reinstated, i.e., the IP is free and clear according to the USPTO.
I see a lot of "half full-range" MEH creations on this forum, but I've found that they are just like Lowthers and other "full range drivers"--that aren't actually full range. You have to integrate a woofer into them at some midrange frequency. Typical vented box direct radiating woofers don't sound very good to my ears. YMMV.
I've been using 1.4" and 2" compression drivers on K-402 two-way Jubilees for almost 10 years now--crossed at 400 Hz and extending up to 16-18 kHz, whose performance is spectacular, IME.
I've also built a true full-range MEH based on the K-402 horn that uses two 15" woofers (I used the Danley SH-96 design as a launchpad for thinking about the design). Unfortunately the SH-96 costs more than $8000US each. You probably don't need 11 drivers in your MEHs in your home listening room, too.
The results of the K-402-MEH--well, you'll have to hear it for yourself. You can bound its performance by reading Jubilee reviews and adding point source capability and superior midbass coverage to those reviews, and also being about 1/3 the size of the Jubilee envelope. For me, using larger 1.4"-2" compression drivers solve problems, including eliminating a set of fairly complex and extremely audible higher frequency crossover filters. The larger 1.4" or 2" compression drivers have become more economical to get very good performance over the past 10 years.
You can continue to use 1" midrange drivers and midrange cone drivers in a 3-way. No one is stopping you. Continue on, please... This thread is about a prospective full-range MEH kit. Elimination of the "real estate problem" in shoehorning midrange drivers between the apex compression driver and the woofers is a big deal. It's okay for the full DIY crowd (including designing their own using spreadsheets and Hornresp) to go 3-way to decrease driver costs (but perhaps not crossover costs), while the kit DIY community is apparently still waiting for a simpler solution.
But you can answer in any way that you wish (short of feeding trolls, of course)...
Chris A
Chris,
This question is the interesting one. Your method using a 2" CD and 15" woofers needs a big horn. The K402 is a big horn by most domestic standards. I am not sure how much smaller it can be and still work properly.
I can understand trying to gauge interest before you put much effort into prototypes etc. but I think if you were able to get a reasonable facsimile of the K402 in wood that could be flat packed then I'm sure there would be a market, how big is hard to know.
A lot of the DIY synergy efforts have been smaller and I think that is because most people don't want massive horns even if they know they need to be to work better
I also think the method of construction of the horn will be important as a rectangular box can be made to flat pack and can be assembled with some glue and a couple of clamps. To do that with a horn would need a clamping jig so it might be worth thinking about that as an addition.
Many of the people interested in flat packs don't have the tools for a complicated assembly.
This forum has a much greater number of true diyers that want to do the work themselves so to interest them it would need to be tempting
You might try AVSforums too as home cinema seems a perfect use for your style and size of horn.
I don't believe that you clicked the link. The patent didn't expire due to time, but rather non-payment of update fees. Read the link for the history.
There are a lot of people in the engineering profession that have held onto the old rules of owning patents, but those have changed--not the least of which is the fees that must be paid on a regular schedule, and that increase in monetary value as time progresses ($1K-$5K, etc.). Recommend reading the patent law forums on the subject. It's a lot different than when I was a young engineer, as well as the "reinstatement" process if fees are not paid on time. Apparently the game is to wait 6 months to a year and then claim ignorance of the fee due date, then the USPTO will reinstate if fee and penalties are paid. But that runs out after 2 years of non-payment duration in a single stretch.
...A lot of the DIY synergy efforts have been smaller and I think that is because most people don't want massive horns even if they know they need to be to work better
I understand your interest in the specifics, but unfortunately you're a little wide of the mark. You probably haven't seen a K-402 up close: wood isn't a panacea, and in this case would not be the material of choice. But I appreciate your interest in trying to guess the direction this might take.
How about providing your own preferences to the posed questions...including all others here in read-only mode reading this. The purpose of this thread is to gather user preferences on full-range MEH design...not so much guessing the outcome.
Everyone benefits from the data exchange on preferences, needs, and constraints. Please share your needs and constraints.I'd like to re-emphasize a point on size: it's not about the size of the horn itself but rather the size of the entire assembly with integral LF performance (i.e., no other horns or direct radiating woofers). I think some people might be thinking about an MEH + bass bin like the other 3-way "full range" MEHs that really aren't full range. That isn't the case here. Think in terms of the total loudspeaker envelope, not horn size.
The comment about the size of the La Scala as a point of departure was made so that the reader can compare apples-to-apples with something that is totally horn loaded and also relatively compact as compared to other fully-horn-loaded solutions that currently exist.
Chris
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Hi Cask05,
Since Synergies are complicated, I would definitely go for building an absolutely no-compromise speaker. I do not want to use the next years thinking: "Ok, these are great, but could they get even better if I bought better CDs/woofers??"
By 1. I would prefer a Be diaphragm compression driver, that actually can be had. Either a JBL 1.5" 2435H which can be bought second-hand or one of the Radians (e.g., the 1.4" 745neoBe). I have no specific suggestion regarding the woofers.
By 2. 100Hz would be fine. From around 100 Hz, it will sound as if everything comes from the Synergies anyway. I have vintage 18" JBL 2245H in 8 cu feet cabs as subs below anyway
By 3. I don't really care. I only use speakers for music, so stereo is fine.
By 4. I honestly do not know. However, a pair of Danley SH-50 are too expensive for sure.
By 5. I have digital crossovers (not FIR though). Regardless of whether active or passive, I think the 'flat phase' prominent in Danley's products should be pursued for sure!
One Q: Do you consider using the Klipsch K402 horns as base for these, or....?
Thanks!
Best regards
Peter
Since Synergies are complicated, I would definitely go for building an absolutely no-compromise speaker. I do not want to use the next years thinking: "Ok, these are great, but could they get even better if I bought better CDs/woofers??"
By 1. I would prefer a Be diaphragm compression driver, that actually can be had. Either a JBL 1.5" 2435H which can be bought second-hand or one of the Radians (e.g., the 1.4" 745neoBe). I have no specific suggestion regarding the woofers.
By 2. 100Hz would be fine. From around 100 Hz, it will sound as if everything comes from the Synergies anyway. I have vintage 18" JBL 2245H in 8 cu feet cabs as subs below anyway
By 3. I don't really care. I only use speakers for music, so stereo is fine.
By 4. I honestly do not know. However, a pair of Danley SH-50 are too expensive for sure.
By 5. I have digital crossovers (not FIR though). Regardless of whether active or passive, I think the 'flat phase' prominent in Danley's products should be pursued for sure!
One Q: Do you consider using the Klipsch K402 horns as base for these, or....?
Thanks!
Best regards
Peter
Thanks Peter--that's exactly on target.
As for your question on horn size...I don't know yet. The reason for asking the questions is to first understand market needs and dimensional variations before offering one or more solutions. Certainly, it would be attractive to talk in terms of a horn profile that controls its polars vs. frequency more consistently than a dual flare straight-sided horn constructed of MDF or wood.
But first an understanding of the overall market/design constraints is needed--and not so much aimed at preferences--because fully horn-loaded loudspeakers aren't really competing with direct radiating boxes. If you want a small loudspeaker and don't really care as much about the sound, then you go in that direction (i.e., not the direction of this type of kit).
If it is the sound that's produced, and you understand the size constraints and physics of horn loading, then the question becomes: what are the available market trades between size and consistent polar directivity control to low frequencies while maintaining effective point source output? People that have heard and love the sound of the larger Danley Synergies (e.g., SH-50, SH-60, SH-96...) with lower frequency polar control and effective point source output have created an apparent demand for a full-range MEH kit.
All the collective answers to the above questions combine into a handful of design decisions...including horn mouth dimensions, expansion profile used, the number and sizes of drivers used, and very importantly, the number and type of crossover filters employed--which are significantly different in practice than those for conventional FLHs or direct radiating woofers in that attention to phase growth/group delay is paramount.
Trading for absolutely rock-bottom driver costs, smallest HF horn mouth size (that's not actually a full range polar control horn), and assuming dual flare straight-sided horns constructed of MDF, and assuming a bass reflex box below the MEH would be used (or living with more limited bass output from the MEH itself) has been the path taken by a few--either in their mind's eye only or in sawdust in actual MEH designs. However it is clear that approach yields a more complex and time consuming solution that to date hasn't led to MEH kits being offered.
For a full-range MEH kit, the approach could likely be different than the above.
But first, it's best to ask questions of those who would want a kit. I find that this type of activity always yields insights into better design solutions.
Chris
As for your question on horn size...I don't know yet. The reason for asking the questions is to first understand market needs and dimensional variations before offering one or more solutions. Certainly, it would be attractive to talk in terms of a horn profile that controls its polars vs. frequency more consistently than a dual flare straight-sided horn constructed of MDF or wood.
But first an understanding of the overall market/design constraints is needed--and not so much aimed at preferences--because fully horn-loaded loudspeakers aren't really competing with direct radiating boxes. If you want a small loudspeaker and don't really care as much about the sound, then you go in that direction (i.e., not the direction of this type of kit).
If it is the sound that's produced, and you understand the size constraints and physics of horn loading, then the question becomes: what are the available market trades between size and consistent polar directivity control to low frequencies while maintaining effective point source output? People that have heard and love the sound of the larger Danley Synergies (e.g., SH-50, SH-60, SH-96...) with lower frequency polar control and effective point source output have created an apparent demand for a full-range MEH kit.
All the collective answers to the above questions combine into a handful of design decisions...including horn mouth dimensions, expansion profile used, the number and sizes of drivers used, and very importantly, the number and type of crossover filters employed--which are significantly different in practice than those for conventional FLHs or direct radiating woofers in that attention to phase growth/group delay is paramount.
Trading for absolutely rock-bottom driver costs, smallest HF horn mouth size (that's not actually a full range polar control horn), and assuming dual flare straight-sided horns constructed of MDF, and assuming a bass reflex box below the MEH would be used (or living with more limited bass output from the MEH itself) has been the path taken by a few--either in their mind's eye only or in sawdust in actual MEH designs. However it is clear that approach yields a more complex and time consuming solution that to date hasn't led to MEH kits being offered.
For a full-range MEH kit, the approach could likely be different than the above.
But first, it's best to ask questions of those who would want a kit. I find that this type of activity always yields insights into better design solutions.
Chris
Yes! I agree: a complicated endeavour like this should be based on the best possible components.
1. I would prefer a large format (4" diaphragm size) Be compression driver, with 1.4/1.5" throat. An 1.4/1.5" throat should (in a well-designed horn) yield better and more consistent directivity all the way up. And a large format driver can be crossed low enough to comfortably integrate with the horn's woofers directly, eliminating the midranges. Best woud be Be offerings from Radian or TAD - or JBL that can be user upgraded with Truextent.
2. 80-100Hz is great. Below that, dedicated subwoofers is the best option anyway.
3. They really must be big, to give good directivity far down. 100x100 cm (or some more) is fine by me, if necessary.
4. Depends. A lot, if the performance is great.
5. Oh yes.
Best,
Espen
Then I hope the solution you have in mind won't be as expensive as Paul Spencer's PSE144 as historically anything not made of wood has been very costly.
I think that your way of going about a Synergy has a lot of merit but for now my preference is not for a 2" CD and 15" woofers which is why I didn't post them. Your first reply made that quite clear.How about providing your own preferences to the posed questions...including all others here in read-only mode reading this. The purpose of this thread is to gather user preferences on full-range MEH design...not so much guessing the outcome.
Spoken like a man who has had big horns for over 10 years
I find that I can go taller in a speaker but struggle to go wider. If I could put them in the corners like you then the width would be less of an issue. My comments were meant to be helpful but it seems like they weren't.
Hi fluid
Theres a number of reasons why Paul's PSE's aren't the cheapest out there .Cad work required , cost of mold's/cnc machining and theres 2 mold's to make one PSE . Guarantee tolerance on multiple pairs . The fit and finish of the glass work and the cost of manufacturing in Australia .
Cheers
Mal
A fully horn loaded full range speaker would have to have a truly large single horn or perhaps a moderately large Synergy horn sitting inside, above, or between split horn paths of a bass horn or between vertically separated direct radiators.
The crossover between the Synergy and the bass system has a major effect on the floor and ceiling boundary interference problems that will be incurred, so should be chosen carefully. Pursue this and you will have to trade horizontal pattern control below some frequency for vertical pattern control.
Celestion's new axidriver CD allows one to do a 300 Hz up horn that isn't Synergy or multiple entry. The key is access to that driver and a good horn to put it on. Autotech makes 32" SEOS that might be adaptable to this. More options are available if multiple entrance isn't required.
I've never heard horn bass for the lowest octaves so perhaps I'm wrong about this. I would use a number of 15" sealed slot loaded woofers for 300 Hz and down. At least two, perhaps four. Cone motion would be less than for any remotely practical bass horn, efficiency at least as good, and physical volume lower. One 15" driver with corner loading is shown to be about good enough in my corner Synergies, two would be awesome, four might be desired if corners aren't available. Of course subs can be brought at some point to make things easier or cheaper.
I could go with something as large as a K-402 in the corners but out in the room they would put even me off. If I were doing something commercial I would go limit it to 24" or so wide, perhaps a SEOS24. I think market size shrinks as the solution gets larger. 24" with absorption at the first reflection points and vertically separated dual bass subsystem for vertical pattern control might be a very good compromise.
The crossover between the Synergy and the bass system has a major effect on the floor and ceiling boundary interference problems that will be incurred, so should be chosen carefully. Pursue this and you will have to trade horizontal pattern control below some frequency for vertical pattern control.
Celestion's new axidriver CD allows one to do a 300 Hz up horn that isn't Synergy or multiple entry. The key is access to that driver and a good horn to put it on. Autotech makes 32" SEOS that might be adaptable to this. More options are available if multiple entrance isn't required.
I've never heard horn bass for the lowest octaves so perhaps I'm wrong about this. I would use a number of 15" sealed slot loaded woofers for 300 Hz and down. At least two, perhaps four. Cone motion would be less than for any remotely practical bass horn, efficiency at least as good, and physical volume lower. One 15" driver with corner loading is shown to be about good enough in my corner Synergies, two would be awesome, four might be desired if corners aren't available. Of course subs can be brought at some point to make things easier or cheaper.
I could go with something as large as a K-402 in the corners but out in the room they would put even me off. If I were doing something commercial I would go limit it to 24" or so wide, perhaps a SEOS24. I think market size shrinks as the solution gets larger. 24" with absorption at the first reflection points and vertically separated dual bass subsystem for vertical pattern control might be a very good compromise.
All true and if you have the money to spend I am sure they are excellent, I only said that they were expensive and they are which limits the chances of more people being able to afford them.
Another thing I am sorry to have mentioned in this thread
Mate I'm not having a go
.Like you said once you move away from , mdf , ply and move to more complex shapes things can just get out of hand .
Cheers
As you might know, the tolerance requirements based on acoustics loosen up as you move away from the throat of the horn--tolerances measured in large fractions of a millimeter at the throat, but loosen up considerably at the mouth. Most horn manufacturers seem to lose track of that, but it's extremely important to note that symmetry relative to the central axis becomes much more important as you move toward the mouth of the horn, not so much accuracy of volume expansion or surface flatness that's required toward the mouth.
And I agree, the high costs of that product you mention appear to be either self-inflicted or someone is making a god-awful profit per horn. I tend to believe the former cause. Choice of manufacturing method and material can drive costs up by a factor of ten at the drop of a hat. Using 3D scanners, 3D printers (for production) or stereo lithography (for prototyping), and CNC is a good way to allow your costs to go out of sight instantly. I know these issues first hand--having spent the bulk of my career in defense and national lab engineering.
The challenge is to not allow that to occur. But there are very effective ways to make sure that doesn't happen and to produce a product that is the same quality acoustically and visually...perhaps even better visually, in fact.
Chris
And I agree, the high costs of that product you mention appear to be either self-inflicted or someone is making a god-awful profit per horn. I tend to believe the former cause. Choice of manufacturing method and material can drive costs up by a factor of ten at the drop of a hat. Using 3D scanners, 3D printers (for production) or stereo lithography (for prototyping), and CNC is a good way to allow your costs to go out of sight instantly. I know these issues first hand--having spent the bulk of my career in defense and national lab engineering.
The challenge is to not allow that to occur. But there are very effective ways to make sure that doesn't happen and to produce a product that is the same quality acoustically and visually...perhaps even better visually, in fact.
Chris
Hi Chris
Looking forward reading how you go about it
. Even the one off diy job's cost can blow out so easy .Cheers
Mal
Yea, I understand the cost sensitivity...that's why I put it in the list of questions, above.
Just to put your fears at rest a bit: the K-402 horn, as a point of departure (albeit not as complex to make as an MEH) is about a metre wide, by 2/3 metre tall, by a half metre in depth. The horn version that I prefer is 25 pounds in weight (11.3 kg)...while the MEH version would be much heavier. Its replacement cost from the manufacturer is $285(US) with their profit thrown in. (They won't sell it to you in horn-only form unless replacing a damaged horn.) And that company historically puts 100% markup on everything based on their cost, including overhead costs of a big company.
That's a significant fraction of the price of an "MEH kit", isn't it? You supply the drivers...or perhaps they're in the kit. The horn is the most difficult part of the problem.
When you consider that plywood or good quality MDF in flat form would be a significant fraction of that cost in raw material, I think you'll see that there is a solution path available that's probably affordable--even for you poor guys living in the land of Oz (a term of endearment as a native Texan living on early retirement pension...who understands value).
Chris
Just to put your fears at rest a bit: the K-402 horn, as a point of departure (albeit not as complex to make as an MEH) is about a metre wide, by 2/3 metre tall, by a half metre in depth. The horn version that I prefer is 25 pounds in weight (11.3 kg)...while the MEH version would be much heavier. Its replacement cost from the manufacturer is $285(US) with their profit thrown in. (They won't sell it to you in horn-only form unless replacing a damaged horn.) And that company historically puts 100% markup on everything based on their cost, including overhead costs of a big company.
That's a significant fraction of the price of an "MEH kit", isn't it? You supply the drivers...or perhaps they're in the kit. The horn is the most difficult part of the problem.
When you consider that plywood or good quality MDF in flat form would be a significant fraction of that cost in raw material, I think you'll see that there is a solution path available that's probably affordable--even for you poor guys living in the land of Oz (a term of endearment as a native Texan living on early retirement pension...who understands value).
Chris
Yeah, this is the crux of the matter, size and cost Vs desired BW, and why when I've 'daydreamed' doing a 'full range' ~40-20 kHz Synergy concept for DIYers and also living on an early retirement pension and SS [huge 'hit' on both], it always wound up being a piezo HF, some reclaimed [analog] TV drivers [or suitable oval equivalent] and cheap 12" woofers 4th or 6th order BP loaded via a conical horn and large reflex or sealed back box, using multiple fine slits to cover the necessarily large mids cutouts required to get a high enough HF XO point to minimize reflections back to the throat, i.e. basically an 'el cheapo' modern day 'take' on a '40s era Altec small cinema two way horn system.
GM
GM