Tower Speaker Question

I have the Samson S7hd's which are the same as the exile xm7. I was wondering if I could put anything inside the speaker like some sort of sound dampener so that it would be quieter for people riding in the boat?

How about a volume control knob in the boat so you can turn the tower speakers down. That is how I do it.

Those are molded ABS pods which really isn't that 'live' of a material. I don't think that is your core problem. However, you could still try a little damping (HushMat, DynaMat, RoadKill, etc.) attached to the interior wall of the pods. It may make a marginal difference. A solvent-based spray expansion foam is highly effective in killing any resonance. Contrastly, a latex foam product will not stick to the pod interior and is useless. Easy does it as you would not want to reduce the pod's interior displacement with too much foam. You could also fill the pods interior with polyester fiberfill which will convert some of that acoustic energy into thermal energy which serves to attenuate the interior radiation. But too much of a good thing will take the spring out of the midbass and leave the sound a little flat. Its a trial and error thing.
If you have a flat cast tower rather than a tube tower you get alot more radiation reflected into the boat.
If you have multiple staggered speakers then some forward speaker radiation gets reflected of the rear most speaker.
Plus, if your tower is forward leaning and/or lower than normal then the problem gets worse.
If you have one pair of speakers always take the highest position.
An EQ can help attenuate the frequencies most radiated into the boat or at least the spectrum that you or your occupants are most sensitive to. The Wetsounds EQ has separate circuits for the tower and in-boat zones so you don't have to influence the in-boat speakers as you are affecting the tower speakers.
Beyond that there isn't much you can do about the major causes when you are pushing the tower speakers hard to reach the rider.

David
Earmark Marine

Ill bet they already have some poly material in them. At Least the 3 I had to replace the defective drivers in did.

David did a good job of commenting on virtually all the possible situations the OP may have. I'll extend the energy on the thought that you can't do much given the parameters you currently have, i.e speaker, tower, placement. My point here is that speaker design will have inherantly diferent Radiation ( some call it "Off Axis" energy or response). I'm not going to explain it here, just google it. Point being that the Off Axis response of a given speaker is pretty much fixed. David offered some simple ideas of trying to affect it but each is minimal in effect and will affect overall fidelity....negatively.
Simply put, if you have too much sound In your boat from your tower speaker(s), you picked the wrong one(s) for you application.

Kramer - I'm sure everyone has the best of intentions here but they missed some specific things regarding the speakers you own.

Yes I'd agree that a lot of this has to do with the tower and position of speakers on a tower i relation to people on the boat. Know with that said, the speakers that you own have some special attributes that can help in exactly this situation. The design of the enclosures do have deadening material already inside. They also have a structural design that add's ribbing into the exterior to both strengthen the enclosure and eliminate internal resonances. Could you add a dead liner inside? Sure. But its effects will be nominal at best.

By nature the HCLD (XM7/S7HD/XM9) designs are going to be sharper sounding with its horn design versus our radiating tweeter speakers (SXT / SMT). In simple terms, the XM7's are designed to throw maximum sound out to wakeboard distance with a narrow dispersion pattern. The SXT/SMT are designed to produce sound with a wider dispersion pattern -- great for surf and party cove situations. Less great for wakeboard distance.

With all that said, I would suggest that you return to the place you purchased your speakers and ask the installer to engage the crossover switch. this will add ~ 3 ohms of additional padding to the horn part of the speaker and has a smoothing effect. Some people opt for MaX horn output. Others prefer a smoother horn output. Our design gives you the choice. We ship the speakers in the Max setting. the reason I suggest you have your installer perform this modification is that you need to remove the speaker from the enclosure. It's not complicated but it is a bit technical.

Without knowing all your stereo specifics (sub / cabin etc), this change should have a very real effect on the sound.

If your running a harpoon amplifier for the speakers, I would also suggest you add the throttle box controller (if you don't have one). It takes the smoothing effect up another level by actively shaping the phase response of the horn. You can vary it from "wake" to "surf". It works well with any brand tower speaker as long as it is a horn design.

If you have any other questions, shoot me a pm.

cheers!

-Brian
Exile Audio

Its all going to depend on exactly what Kramer and his occupants are experiencing and how he normally uses his speakers.
As Duane mentioned there is the off-axis consideration. This can be described in two different respects. First, you have the on-axis versus off-axis dispersion pattern. An HLCD tends to have a narrower dispersion pattern while a conventional or surf speaker has a broader dispersion pattern. If you are trying to get projection to the rider then a broader pattern spraying the rear occupants can be counter productive. If you are looking for a higher ratio of amplitude at projection range versus in the boat an HLCD may be preferred. The rest of the problem would be too bright of a speaker or just playing it too loud which punishes the rear cockpit occupants.
The other issue is a speaker's near field polar response which dictates that all speakers will have alot more sound energy around the entire perimeter of the speaker that will collapse to a far narrower pattern as you increase the distance away from the speaker. If the tower is low and forward and the driver and observer are getting alot of overhead radiation, especially with a flat arch, then this is just amplitude related and there is not much you can do without a total speaker relocation like over the top or on the outside of the tower.
As Brian mentioned you can alter the speaker's treble response with a passive attenuation circuit in the speaker or an active null circuit within the amplifier. Or you can acomplish this with an EQ. In any case its equalization that is reducing some of the more strident treble aspects when listening near field. This would be particularly effective for surf or listening at rest. But for projecting to wake range you are essentially reducing the speakers peak output. If that causes you to turn the overall output up to reach and satisfy the rider then you are still going to have more residual output in the boat. And if you are trying to drive a surf speaker with authority at wake range you may expose the speaker's limitations and that won't be a pleasant experience for the in boat occupants.
Some boats are less cooperative and the intended usage can compound the problem. Its not a brand thing. And there isn't always a magic pill. Larger or warmer speakers can help depending on what the real issue is.

David
Earmark Marine

Good points David.

I do like the magic pill idea tho :>

Thanks for all the replies. 90 percent of the time we use the boat for wake boarding and so the speakers are turned up loud enough to hear while wake boarding and it bothers some people that ride with us. I do have the throttle box so I will have to play with that. If I did engage the crossover am I still goin to be able and hear the music while wakeboarding?

Kramer,
Give it a little trial.
The treble section is normally set to be unbridled for maximum projection and so that the sound will still be intelligible at wake range. Distance and noise competition tends to be a little harder on the distinctive treble qualities. So some of that extra emphasis is welcomed at 80 feet. But the extra treble is also in the spectrum that the human auditory system is particularly sensitive to. Our pain threshold is also coincidental with the area of increased sensitivity. The extra emphasis may not be welcomed at close proximity especially at a very high volume level.
So you can bridle that a little with both the internal tweeter switch and the Throttle Box. In doing so you will also sacrifice a little peak output and projection ability.
Try it and attempt to find a balance between what the in boat occupants want and want the rider wants. It can't be a perfect scenario for both.
Here is another possibility. You can install angled shims between the speakers and tower (if you have the flat arch) to aim the speakers upward and parallel with the water and more over the head of the rear occupants when the boat is pulling and squated.

David
Earmark Marine