[Kludden]

Hi zygdr!
It is hollow. Thickness off the tube wall are 4 mm. Inside of the tube are the same as the inside of papertube by the exciter.
No vented, thats why i could glue the backside with silicon.
Kludden

[CLS]

About venting, I mean in between the VC former and the wood tube. Or on the side of wood tube. 

Or, in reality it's no big deal since such operation shouldn't produce big excursion, thus no significant volume change in that cavity.... 

[zygadr]

He said it's a "tube":

 

I'd suggest, maybe it'd be even better to have some venting paths among the VC former, pole piece ... etc. 

Yes, I know he said it's a ''tube'', but can you find ''wooden tube'' at your local hardware store??????????  

[zygadr]

inrank, good find!
I have sent them an email on availabilty in Australia. If I can get it I will.

[CLS]

How about a lathe, or a big drill bit? 

[Kludden]

Jepp.
I have an wood lathe and an metall lathe . It is important to get some good wood that not cracks.
You could also see my wood horn on page 73 behind the cc-board, left top
Kludden

[zygadr]

How about a lathe, or a big drill bit? 

Cheaper to buy a proper ''EXCITER''

[pol_bct]

Yes, I know he said it's a ''tube'', but can you find ''wooden tube'' at your local hardware store??????????  

napkin ring  ?   

[zygadr]

Got an answer via email this morning from CLARK SYNTHESIS whether these transducers can be used for music reproduction - mounted to the back of a sheet of timber/ply etc.

The answer was ''YES'' !!!!

Have we overlooked these?.........they are far, far, more powerful than these Chinese toys (exciters) that we have been playing with.
They don't need any special honeycomb panels or anything light and rigid..........just a sheet of ply and that's it.

Remember these are not only ''bass shakers'' as most people would think. They have an audible full frequency output from 35hz - 17khz and are similar to the Roland Star transducers.

The official specifications PDF document states : ''full audio bandwidth capabilities to allow for wide variety of audio applications''........and.........''The transducer has full audio bandwidth capabilities to allow for any audio application''

The starter model is on special  ($69) and is 8 inches in diameter!

[CLS]

Ah, you forget the one I brought up -- the guy who built piano sound board as the panel from 'the other forum'. He uses a Clark synthesis transducer.

[zygadr]

''THE OTHER FORUM''!!!!!!??????

Well then, if it works, this forum is about to take a different approach I feel.

The theory of a powerful exciter and wooden board is immensly interesting and a concept that can not be ignored 

[panomaniac]

Wood would be better because......?

More bass?

[CLS]

Easy, easy....

That guy disappeared anyway, only one post left, never answer my questions. 

Your last sentence is indeed very true. My experiment of glass / dry wall revealed something very interesting. Powerful exciters are desirable, too.

Talking about powerful, as I read the product page of NXT (hi wave), it seems that the "hi shove" is not about wattage, but more on the weight of driver. Interesting, huh?

I suppose that additional weight should be accompanied with stiffer suspension to complete the 'shove' action.

Anyone tried adding weight to the excitors? Or how is that different from spine-mounted?

[zygadr]

When the refer to the ''weight'' they mean the amount of force that the exciter applies against a surface (''shove factor'').......nothing to do with the weight of the exciter, but the high shove version is heavier due to a more powerful magnet and the mounting/casing around it.

If you just applied more weight to an a standard exciter you will no doubt damage the spider/voice coil alignment.

The high shove exciter by the way, is like comparing an ant to an elephant against the Clark Synthesis transducer. The difference in price is only $30 US.!

[CLS]

I think there're two factors.

The load on suspension of transducer can be arranged so that the movement of VC isn't affected. (suspending, frame support... )

And the "shove" comes from the motor of transducer. The motor has 2 major portion: magnet and VC. Now the magnet is fixed (and tinny on el cheapo), but we can feed more power into the VC (before burning it). Eventually, it is the efficiency. What I'm wondering is the role of mass inertia.

Efficiecy aside, what on earth is the difference between hi/lo-shove transducers? ( One cheapo on big enough PS foam board is pretty loud already! )

[pol_bct]

Wood would be better because......?
More bass?

CLS
"Anyone tried adding weight to the excitors? Or how is that different from spine-mounted?

the very fist DML I bough was heavy weight about 400grams
which was intended to be used on an horizontal panel
the output level was very low, but the bass goes down to 30Hz

later, others experiences show that a very leightweight panel has a HI-output but lacks of bass extension.
the wood panel I tried, (3mm plywood) goes  very  low but with attenuated output.

POL

[j gale]

Re: Clark synthesis transducer ($69 one) I just did a quick and dirty experiment, made a stand for it and attached it to a 6'x2' 3mm plywood panel  at about 1/3 mark centre. Panel is suspended from a frame with 4 elastic bands 1 in each corner. The Clark comes with a bunch of mounting parts including a plateabout 3" in diameter so married that to panel with 3m tape. Full range it didn't sound very good. Tried running them off a sub woofer plate amp. With the cheap 2 for $5 exciters (bargain of the century) running full range and the Clark limited to bass duties it was pretty good. I usually use a couple of 15" woofers in H frames with the panels. So far I think adding one of these $69 transducers will give enough bass so that woofers etc won't be needed. The panel could do it all.At this point I don't think one of these could take the place of regular exciters. I intend to try different ways of attaching it to the panel to see what difference it makes.

[CLS]

Folks, thanks a lot for sharing.

Hi j gale,

That's interesting and very promising! Did you use 2 types of transducers on the same panel? If so, any problem of interactions between them?

I got a pair of Dayton's bass shakers, should be suitable for such task. I've been thinking of doing it, but as always, too many things to do with too little time....   

[zygadr]

Thanks j gale.
Well, I would guess at this point that even with further experimentation, I agree that these tactile transducers are not going to sound as good as the normal exciters we have been using.

The high shove version is designed to activate and drive ''large panels'' apparently due to their stronger/more powerful vibrational effect.

Using four of these mounted on a spine would enable a large and heavier than normal panel to sound quite efficient I would imagine.
We would not have to be limited to EPS to get a loud sound. Corrugated cardboard, or even thin plywood which is much heavier than EPS might actually sound very good with these high shove exciters?

[CLS]

I think of cars.

MB with big capacity V8 on Autobahn vs Elise (or Caterham) on country road. 

High power vs agility....

Eventually, nothing can deliver perfection in every aspect. This brings us back to multi-way speakers.