"It would be very interesting to compare the "absorbing" product to the "mechanical grounding" method to hear which is more effective in minimizing/eliminating the bass boom."
It's not necessarily either/or; neither excludes the other.
Also, IF lowering the tuning frequency of the port by reducing its cross-sectional area (as described a few posts up) actually works, I think that approach holds out more promise than port-stuffing because it is less likely to have a downside.
Duke |
It would be very interesting to compare the "absorbing" product to the "mechanical grounding" method to hear which is more effective in minimizing/eliminating the bass boom . I'd hope Mr. Horning would offer more input, who has more insight on this speaker than him?
Regards, |
I have found that putting speakers on a Symposium shelf will reduce the tendency for bass to boom, particularly if the flooring is suspended (not on a solid concrete base) and made of wood. I use Svelte Shelves (the thinnest Symposium platform) which is less than an inch thick. Other platforms are much taller. I would not say that platforms are a "generic" positive, they can make some systems sound too dry if that is already the tendency of the system. In other words, you will have to experiment.
If booming is an issue, energy absorbing shelves or footers like those by Stillpoint (also energy absorbing, and not designed to couple the vibrational energy to the floor) will be of help. |
Hi there and thanks again for all the inputs.
Duke, I hope it's not over me that you're run into those sleepless nights.
Tommy isn't making many suggestions. He just says it's very uncommon to have such issues with the Eufrodites.
Jefferey of High Water Sound, Horning's importer in the US, recommends using either Eden Sound feet or Symposium bases for the Eufrodites. His recommendation isn't just for solving boominess but is a generic one.
Does anyone have any experience with those products?
Cheers. |
Amuseb,
Tommy wasn't keen on the port damping approach apparently. Did he offer any suggestions for the bass issues you have? As the builder you'd think he knows this speaker better than anyone and could really help you.
Regards, |
Your first step should be to couple the speaker and then wait a few days for the unit to find ground. Until you do this properly your retuning of the enclosure may lead down a path of continual frustrating results. There are ways to mechanically ground a ported speaker so that no internal damping material is needed but probably not now in your case without serious intrusion. Damping will reduce dynamics coupling will not. Tom |
This is a long shot, so consider it just the ravings of an insomniac:
It is possible that the enclosure is a transmission line/tuned port hybrid of sorts, and if so, you might be able to tighten up the bottom end a bit by lowering the tuning frequency. One way to do so would be to reduce the cross-sectional area of the port over its entire length.
Remove the stuffing from the port, then measure how far the port extends into the box (horizontally). Cut several boards that long, and just wide enough to fit into the port. Stack enough such boards in the port to roughly cut its cross-sectional area in half.
If the box functions as a reflex box, we've just lowered the tuning frequency somewhat. And that just might be a better "fix" than stuffing the port with damping material. If the results seem promising, find the optimum number of boards by trial-and-error, and then if you want to, glue and/or screw the boards together to make a solid block, and maybe wrap the ends with electrical tape or some such to give you a snug, rattle-free friction fit.
Theaudiotweak's suggestion of improving the coupling between speaker and floor may work very well, I don't know, I have less experience with that approach. I don't see how it could do any harm (unlike the things I've recommended, which very well could be detrimental, especially in the wrong dosages... but at least they're easily reversible).
Duke |
Even though Tommy's remark, I agree with your statement, Duke.
I'm continuing the research... |
Using absorbent material in the ports isn't the ideal, but if the Eufrodites' way of working isn't working for you and your room, then imo it's reasonable to try to find a solution that is a worthwhile net improvement.
I design speakers too, and most of my designs have user-adjustable ports, because I can't always reliably predict in advance what the room acoustic situation will be like, where the speakers will be positioned, and/or what the output impedance will be of amplifiers they might be used with. I have one customer (a single-ended triode amplifier manufacturer) who went all the way to plugging the ports on his speakers, so they are now sealed boxes. Yeah that theoretically goes against their "way of working", but it's what works best for him, his amps, and his room (speakers up against one wall, listening couch up against the opposite wall, so lots of boundary reinforcement).
As for optimizing the type and amount of damping material, I'm afraid it's a matter of trial and error, and a juggling of tradeoffs.
Duke |
BTW, I asked Tommy about the damping materials and shutting the bass ports, he said: "all the things you are thinking of doing is against the whole idea of the Eufrodites way of working". |
Yeah Tom, I figured you had something to offer in this domain.
Where can I see some more details of it?
Thanks. |
The Horning website is pretty lean of info and pictures. There was a model reviewed on 6 Moons way back and it appears that they have made an attempt to couple the speaker to the floor. You do not want to damp any speaker you want to couple the speaker and provide a specific direction for the resonant energy to travel to ground. In this case the floor. If you impede the flow of energy from the cabinet it will sound different and most likely worse.
You may have an EF5 tornado in a box and your room. The energy is trapped and is trying to make it's way out and you will not be able to stop that energy that you paid thousands for. Why would you want to do that? The end result should be to make a funnel cloud of that 2 mile wide tornado and channel that energy to earth because that is what it is trying to do now. You do not want to stop that flow but to steer that energy full speed ahead to ground. Make use of all that energy make it work to your advantage make it work in one direction. I hope these concepts are of some help.
I myself design and build products that enhance the mechanical grounding of musical instruments that touch the floor. I am also a member of a company that designs, builds and sells similar technology for home and commercial audio products. Tom |
Listening along, I find that the stuffing of the ports also takes some good qualities away.
The music is less dynamic, the loss of bass is also making it be missed across the spectrum, overall the sound is more itchy and less musical.
Of course this is just with the two provisional pillows tucked in the cave.
Will check the recommended materials in different configurations to see how they do.
Cheers. |
Amuseb,
It`s good to know that such a simple (and cheap) solution has led to this level of improvement.Turning your speaker into a partially sealed box is obviously effective. I`m glad you can enjoy your system now.
Regards, |
I've stuffed into the ports a couple of polyester pillows I have here under hand.
So far the impressions are that the more stuffed, the better it is for the bass control.
With this understanding, Duke, would you have any fine tuning to make on your recommendations above regarding the material to be used?
How about using better feet for the speakers? There are a few guys that make sort of dedicated such spikes.
Would that add to the gig?
I highly appreciate everybody's help here with bringing me back to enjoying my system. |
"What material would be best to use for an appropriate stuffing?"
I'm not sure. With the towel, what you did was add flow resistance to the port; you made it significantly harder for the low frequency energy to get out of the port. If the towel was filling the port completely, then you added a lot of flow resistance; the more airspace around it, the less flow resistance.
My suggestion is, trial and error. Bigger towel, smaller towel, see which is a step in the right direction. Maybe open-cell foam (when you "haaaaah" into the foam, can you feel the heat form your breath on the other side? If so, then it' open-cell foam), again I can't tell you how completely you should fill port, or how deep the foam should extend into the port.
Long-hair wool was mentioned. That's great for stuffing a transmission line, but imo the intention here is different - we're trying to reduce low bass output, rather than facilitate it. Unless you packed it tightly into a cloth bag and crammed it into the port - then, it would be behaving more as flow resistance than as gentle damping along the length of the line. Imo you can accomplish the same thing for less money with tightly packed polyester batting or fiberfill.
The variovent is itself a flow resistance device, and one with a rather strong flow resistance, maybe more like packing the port tightly with a towel than like open-cell foam. You'd want to turn the cabinet almost into a sealed box, with the only pathway between the inside and outside being through the variovent (which is dense fiberglass compressed inside a plastic housing that has airflow holes in it).
Duke |
Tom, you reckon right, neither Kentucky nor Louisville is where base is.
Can you educate my layman self on what the mechanical grounding elements are?
Regards from the city of lights. |
Well there is a Paris Kentucky and I reckon the word reckon is used there many times a day as it is in Louisville, that other French name sake.
I'd have to ponder the variovent and how many and what size. That's probably more than just drilling a random hole I reckon. As far as material to place in the vent well that would be long hair sheep's wool.
Before you do any other mods you must mechanically ground your speakers. And after doing so the speakers and the grounding components will take a few days to settle in. There are several other enhanced grounding methods that could be applied to both the cabinet and the driver. All of which would improve performance and void the warranty. Tom |
Hi,
So further positioning trials have somewhat improved the boominess.
And then, following Duke's post, I stuffed towels into the woofers' ports and I think this is making an important contribution to the battle!
For sure, right now, I can listen to music and enjoy it.
Big step forward. Thanks a lot.
What material would be best to use for an appropriate stuffing?
Other than that, from the positioning trials I came to spread the speakers even further apart from each other which opened up the sound stage and brought in a lot of space between the instruments. So way to go for this collateral benefit.
Tom, how would you reckon the Variovent be installed in my speakers?
It seems that large speakers require a few of those. How would that be done, any idea?
Thanks a lot to all the contributors so far. It's helping a lot.
Regards from Paris. |
These have been around for 15 years or more and they work.
MB Quart had them as well as Audio Concepts
http://www.gattiweb.com/images/dynaudio/variovent_data.pdf
Tom |
Duke,
That is a good idea for a ported speaker.If that does not work or if it partially solves the problem would some degree of bass absorption benefit him?
Regards, |
It sounds to me like the speakers are getting a lot more boundary reinforcement in your room than what the designer anticipated, and reducing the amount of bass they put out may be a lot easier than changing your room's acoustics.
I have zero experience with the Eufrodites, but eyeballing the speaker, I see four woofers and a big port, and the description sounds like it's a transmission line variant. You might try attenuating the port's output via damping materials. Open-cell foam, polyester batting, a bath towel, whatever you have on hand. The idea is to find out if this general approach makes a net improvement, and then you can fine tune it from there. You might get better results (tighter bass with decent impact) by solidly sealing off the ports completely, turning the bass system into a sealed box, perhaps even with that damping material inside.
Duke
dealer/manufacturer |
Try using mechanical grounding devices under your speakers and components they work. They direct mechanical resonace and energy stored within the component to ground. Less boom and blurr.. Tom |
That`s why I had made the earlier suggestion that a good bass trap for absortion of the excess bass energy.Why not give it some consideration? Changing placement has not helped and I don`t believe your amplifiers are the issue either(certainly not the Horning amp).You have a significant investment in your components, a bit more to try some bass absorption seems reasonable.Have you emailed Tommy Horning for his input?
Regards, |
Hi,
So I've been moving the speakers in, out, more toe, less toe, slanted forward, etc, etc.
But the boominess is there all the time.
Very clearly the issue comes from the left side of the room. I'm not sure why. There's a glass door there leading to a corridor which some experts told me would be where the problems comes from but I've covered the door with 3 types of fabric and carpet and it changes absolutely nothing, nada, gurnisht, niente.
There's also a little wall of about 1 meter that comes into the room on the left side about 3 meters from the back wall which creates some kind of a so called "niche" there on the left and when I stand there the boominess is heavy.
When I stand next to the right speakers, there's no boominess at all.
It is so annoying, I can't even start telling you how much.
I don't even need my system to be the best in the world, all I want is just to listen to music which right now is very challenging.
I'm not into high end hifi for a long time but I have so far maybe 5 pairs of speakers in this room with never even a hint of boominess, and now this.
What can I do?
Help!!!!!! |
Thanks a lot Assad.
On a business trip this week, will do some trials when back home and report the outcome.
Charles1dad, regarding professional consultants, mmmm, if I knew one that wouldn't take me to bankruptcy and for little result (like many times consultants do), I would consider that.
Has anyone had any experience with resonators and their efficiency in untying nods?
Regards. |
Assad,
You make some very good suggestions and have experience with these speakers. I 'd agree maximize speaker placement (although it seems there are some practical living room limitations). If this is only a partial solution then proper bass traps are an option to quell excessive bass energy into the room. I believe that the Hornings can work successfully in this room with some effort, it's a very good speaker. Amuseb, have you considered a professional consultant, your system is worth it.
Regards, |
Hi there,
I have been a Horning owner for 15 months now. Before you do anything to your room ... don't!
So Horning's energize the room in a way few other speakers can (this is both good and bad).
My strongest hunch is that the speaker in that room in ITS current position is causing the problem.
Given that you can't turn the room 90 degrees (short wall to long wall placement or vice-versa) .... I would recommend you start to pull the speaker out a little or move it back a little. Same with toe in, and distance between the speakers. Little changes will change how nodes and standing waves buildup!
I had imaging and bass issues on the short wall, so I moved to the long wall. Then I had boomy bass issues for a while there as well (but the soundstage and depth were insanely huge) ... so I stuck with the long wall, threw in a few plants into the corners and around the inside of the Hornings (between the speakers) and it helped a lot, but the bass was still not tight enough. THEN, on a whim, one day I moved my left speaker (kept the same toe in) closer to the right one by about 1 cm ...and then ..everything clicked! deeper sound stage, super tight bass (everywhere). And if you are wondering ...I measured everything to be symmetric. All I can think of is that the multiple woofers in the back excite rooms and since most rooms are not 100% symmetric ...one side was exciting things more than the other side.
Try that and report back, if you can.
AND UNDER NO CIRCUMSTANCES should you use bass traps around the speaker! The back wall behind your ears is fine for that. Hornings are true dipoles and their soundstage is all behind the speakers .... bass traps will suck the life out of those speakers! If you want to break nodes up .... use plants in the corners ...you want reflection/diffusion ...not absorption!
BTW, the Sati 520 should make those speakers sing! I have the Puresound m845 and it really controls the speaker very very well! I came from KT-88's push pull with a lot more power and the speakers sounded "just ok". Goes to show synergy!
Good luck and keep us posted. We are here to help!
-Assad
|
Try Not to sit to close to the back wall. About 2m/7ft away from the back wall. |
Thanks Charles1dad,
Yap, that possibility of course has crossed my mind.
My room is about 5.5X7.5X3.0 meters.
Speakers are about 3m apart, 60 cms from the back wall and my listening spot is about 3 meters out.
I can also say that in the listening spot the issue is smaller although bass should be tighter. Outside of the spot, the bass is really annoying to my ears and as music is on a lot in the house, it's bothering.
Most of the bass issue is coming from the left side of the room.
The problem with bass traps is that my system is in a family living room and I already hijack a good portion of the room for my musical purposes, adding bass traps can make me even less popular with my dear ones.
Thoughts welcome. |
Have you considered it may be speaker-room interaction?
Acoustic bass traps may solve your problem.
These speakers can generate significant bass energy, how large is your room?
Regards, |
No doubt you have them placed a good distance from the rear and side walls and of course as required with all horns you surely have a large room. |
