Adding more layers of rigid and damping increases the isolation about 6 dB per layer.
Still exploring ideas.... what if; I focused on the mid cabinet, in effort to make it worthy of having the horn mounted to it. The cabinet itself is well braced. 3/4" BB spaced evenly, ~ every 6-7"s... There's actually a little more bracing at the back of the cab not shown in this mock up...and the woofer baffle is double thick, 1.5". This cabinet can be fixed to the sub cabinet, using metal hardware.
This is not enough??? If I added a layer of granite tile on top of the midwoofer box, mounting the horn to this, using the SS hardware, does the heavy mass approach work in this situation?
This is not enough??? If I added a layer of granite tile on top of the midwoofer box, mounting the horn to this, using the SS hardware, does the heavy mass approach work in this situation?
Or is the point that the rope suspension is just so much better why entertain anything else...
It's been 30 years since I tried to design anything outside what I build in my garage, but fixing the rope bed in three axes (while balancing a lower number of suspension ties against a higher tension which would increase transmission) would simply require you have front/back suspension ties. I believe a weave would make it more fiddly than it would help.
Fine adjustability would probably be easier if they all tie to a mount such they are all on a common plane (I was going to add flat plane, but that would be redundant) - but the 2-d shape of that plane could be a circle, triangle, etc. and it doesn't have to be a physical plane (i.e. like the back of a speaker driver, six screw eyes can form a circle on a plane) although I think a solid plane level wrt to gravity might be less likely to introduce multiple resonances (say, if the mounting legs or suspension ties are unequal - although maybe unequal lengths are desirable?).
A triangle with two ties per mounting point (>15° between them) wouldn't be that complex if the weight distribution works out (two points and four ties to the sides of the mouth and one point with two ties at the rear might be similarly loaded?).
Alternately, while I don't know what damping/isolation/transmissibility you are looking for (and long ago forgot most of the relevant math to try to convert among the data sheets), but you might also ask one of these places if they have an appropriate design. Some are big honking things, but there are some for aircraft electronics so they should have ones aligned to 70# of weight - just not sure if the frequency and damping are what you are looking for.
https://springcompany.com/products/vibration-isolators
https://vibrodynamics.com/our-products/wire-rope-isolators/
If you are asking me, I think it would look cool (now I kind-of want to make one to play with myself) but functionally, I would talk to the experts that design them to verify if they provide the appropriate damping/isolation/transmissibility you are seeking. They could be tuned in a way that makes things worse for your application.
I also have an oddly shaped horn (e-jmlc 300) and have placed it on a big sand bag. It works very well and it is easy to make adjustments. It also dampens resonances in the mid bass.
//Anders
//Anders
Nice, minimalist approach Anders!
Your experience and philosophy seems to have many parallels with mine.
No matter how good the implentation - and this is and remains personal, I can't seem to listen through the localization issues of separate subs.
Certainly not in clubs, but neither with a room-corrected high-end setup like the one that Grimm demoed at DAE.
The three of us concluded that this - although by no means bad:
... was several levels below this, in terms of homogeneity and overall rendering quality:
Last edited:
Despite the fact that the latter (bare) speaker system is cheaper 😉
It doesn't imply the horn system is free of (subtle) artifacts. These primarily concern the (integration of) horn(s) and deserve an extensive post/discussion, for which in advance I invite the horn scientists and experts on this forum to participate.
It doesn't imply the horn system is free of (subtle) artifacts. These primarily concern the (integration of) horn(s) and deserve an extensive post/discussion, for which in advance I invite the horn scientists and experts on this forum to participate.
Last edited:
Because of the time of year,
![Hi-Fi Loudspeakers and Enclosures [2nd edition] by Abraham B. Cohen_Cover.jpg](https://www.diyaudio.com/community/data/attachments/1032/1032409-0872340a96a02f8adbed72b80259bc6b.jpg?hash=CHI0CpagL4 "Hi-Fi Loudspeakers and Enclosures [2nd edition] by Abraham B. Cohen_Cover.jpg")
a small (nostalgic) gift.
Camplo will particularly appreciate chapter 10 😉
a small (nostalgic) gift.
Camplo will particularly appreciate chapter 10 😉
Last edited:
Thanks 🙂
The heart of all good systems i have owned/heard is a solid two-way. I have another pair of 416 woofers so the plan is an MTM set-up eventually, only problem though is that the current system is quite satisfying so it is moving slooooowly.
//Anders
Sorry, it struck me someone might read this in many different ways (there are much more experienced experts here in many fields) - my use of "design" was a young draftsman in a mechanical/fabrication shop going to school for Mechanical Engineering who had a concern later validated by the customer's engineers - so I got to design some simple industrial machines. After Desert Storm #1 I went another way (Army) so ... I did not mean to imply anything about speaker design.
I personally would not g go to extremes, it's not that important. Just good solid mounting should be fine.
It's just that extremes seem to be your favorite.
Lack of high frequency reverb, more directivity and headroom? Room seems to more dampened. Can't beat the SQ increase had by increasing directivity.
Touché, I appreciate that. I've got like 3 different pathways to entertain now, but I think a single SS mount at the balancing point might do the trick 😊
In both cases, the room wasn't a major factor due to the sophisticated arrangement, the treatments and - in the case of the Grimm, room correction.
The LS-1s are among the best monitor systems, according to the German magazine Audio even the best ever and it is certainly not a bad sounding system.
My expectations were high, but it didn't live up to that. We thought the whole thing sounded pretty lifeless, even a bit flat and it lacked a certain coherence, naturalness.
The classical piece that was played failed to impress in many subtle ways.
Keep in mind that the Grimm system costs around 50k, so one has to be critical.
In my opinion, the individual (material) characteristics of the drivers also play a role; Be for the tweets, Magnesium cones and Aluminum for the subwoofer.
The Kii Three in the previous room sounded much more coherent.
Naturally, the double horn of the Blumenhofer is an important aspect, but certainly not the only thing.
It was remarkable that this system was the only one of the entire show capable of providing the illusion of "they are here" and "you are there", even more since the entire chain consisted of old-school analog equipment.
As said, later I'll delaborate on some specific characteristics of the radiation pattern of this system.
Last edited:
After some time, I have come to know a few aspects about the drivers I have and how they are set up. Making due the best I can without a proper horn stand, I have come to know the horn at 90 degrees lol. I have used the 15" and the dual 18"s, separately, as a mate to the horn, crossed at 200hz, I can take a sine signal and sweep back and forth of each side of 200hz and hear no strong transition, whether using 15" or 18"s as the mate. The Horns mouth is about the height of the 15" so approximately 16" above the 18"s in these experiences. I must recognize that an impressive 2way is had between the horn and PPSL dual 18"S crossed at 200hz.... I want to try some some stress testing but consider, during my one channel only listening, this combination has been a real joy. I have a space in the back of my mind for this combo, as the mains. The aspect of SQ that it presents, is one that I did not anticipate, the SQ aspect known as bandwidth....Silly for me to not consider it, since I have been chasing this low tweeter XO point from the beginning. But, the full, undistorted passband, south of the tweeter, from just one point in space, is definitely underrated. Yes I have a messed up, in-room FR, due to poor room acoustics, but non the less.... If I switch the mating woofer to the single sealed 15", the bottom end is sorely missed..... Part of the idealization of my design was To have a midwoofer and create an ideal "Port"....Taking the same concept, of a Vented design essentially adding LF in the form of an additional sound radiation source, I have, in a way, placed another radiation source, to perform the same duties that the vent would, alleviating the upper woofer from any real excursion, no less. Even as a Slot load, this "vent" outperforms a BR port, I think. Cost more, but thats not the point. SQ is higher, in my opinion.
That leads me to a question. Does anyone have any real technical qualms about a slot loaded woofer? Personally, I think to keep this type of thing in the bass region, due to the lower resolution perceived at these frequencies. Yet Slot loading is the heart of Synergy Horns, and this takes place well into the upper midrange... The same blur (multiple peaks) in the IR will be there, maybe somewhat like a Tapped horn in ways. Maybe this is the reason for @mark100 's interest in the temporal EQing? If the synergy crowd is not having an issue, per say, using, multiple, slot loaded drivers in the upper mids, I am more confident about using a slot loaded woofer, in bass region, is what I am getting at. My lower woofers only need to make it to ~200hz and the PPSL I designed, makes it there. It seems adding additional redundant sources, is the name of the game, for improving Bass response, in a room. I wonder, am I not taking advantage of the space above the lower PPSL, by not using yet another, matching PPSL, thus creating 2 redundant sources that are now able to be so, from 200hz down to 20hz. This could be done within a space that would allow coupling of 4 woofers almost to 200hz and below.
Another thing that is bothering me, is my failure to keep the tweeter at ear level....I never anticipated such a large horn, and now I have over shot my height goals....I could re-engineer the cabs to a shorter height, if it really is that big of a deal to me... a ~37.5" stack of cabs would put the tweeter at ~47".... Much better than the 53" center tweeter height, I am looking at now.... I kinda feel like having tweeter, at ear height, is a huge part of the experience, a sort of unappreciated luxury?
Just some thoughts. The low 200hz XO is creating some possibilities I did not consider. With the low XO point, intermodulation distortion might be more forgiving, allowing me to retain a high perception of SQ, though, excursion may exceed 2mm at times. The most practical idea would be to run the 2 18's, stacked. Dual stacked PPSL would be interesting to say the least lol.... a MTM using PPSL would be very impressive in my opinion. Thinking out loud... If I remember correctly, @gedlee decided to keep the 15" in his 2way, above about ~100hz. I can appreciate that idea just by looking at an excursion plot of 15" diameter woofers.
Another thing that is bothering me, is my failure to keep the tweeter at ear level....I never anticipated such a large horn, and now I have over shot my height goals....I could re-engineer the cabs to a shorter height, if it really is that big of a deal to me... a ~37.5" stack of cabs would put the tweeter at ~47".... Much better than the 53" center tweeter height, I am looking at now.... I kinda feel like having tweeter, at ear height, is a huge part of the experience, a sort of unappreciated luxury?
Just some thoughts. The low 200hz XO is creating some possibilities I did not consider. With the low XO point, intermodulation distortion might be more forgiving, allowing me to retain a high perception of SQ, though, excursion may exceed 2mm at times. The most practical idea would be to run the 2 18's, stacked. Dual stacked PPSL would be interesting to say the least lol.... a MTM using PPSL would be very impressive in my opinion. Thinking out loud... If I remember correctly, @gedlee decided to keep the 15" in his 2way, above about ~100hz. I can appreciate that idea just by looking at an excursion plot of 15" diameter woofers.