[bhobba]

Hi Hugh and All

Had a few minutes to kill and decided to catch up on the latest with the Vsonics now that Peerless has gone kaput to see what you plan to replace them with.  In your news it was said it would be replaced with a driver from SB Acoustics but in the build thread a SEAS driver was mentioned.  Can someone clarify?

Just as an aside are the new drivers paper?  With all the new materials they have these days like magnesium, aluminium, nomex, nextel etc etc I would have thought paper a bit old hat.  A friend of mine recently listened to some of these new materials in some German speakers (aluminium I think) and really noticed a loss of 'warmth' compared to his current paper based (but still excellent) Axis LS88's.  He didn't really know what to make of it - whether it was better, worse or just different.  Personally I must admit to preferring the 'sterility' of the new materials - but that's just me.  I lived for many years with paper and had no complaints.

Thanks
Bill

[AKSA]

Bill,

I'll handball this one to Laurie, whom I'm seeing tomorrow.  He is presently trying to acquire the new SB Acoustics 12" woofer, believe he's making some progress, but haven't heard the latest.

Cheers,

Hugh

[bhobba]

I'll handball this one to Laurie, whom I'm seeing tomorrow.  He is presently trying to acquire the new SB Acoustics 12" woofer, believe he's making some progress, but haven't heard the latest.

Thanks for that Hugh.  A two way with a 12 inch woofer - now that sounds interesting.  Can't wait to hear the details.

As an aside due to my arthritis I cant really do DIY stuff.  However a good friend of mine in Canberra thinks he may be able ot help me out so eventually getting some of your DIY stuff now looks possible.  This makes me feel 

Just had a look over at SB Acoustics and I am a bit unsure how Laurie will use the 12 inch - it is really bad above 1k.  Even the 8 inch is pretty bad above that.  Interesting to see what actually eventuates.

Thanks
Bill

[AKSA]

Aha, Bill,

My serious mistake.....  you meant the VSonics, I was thinking of Big Ben......

The VSonics have been reworked for the Scanspeak H1288 8" woofer.   All future crossovers/enclosure design will be set up for this driver.

My apologies   

Hugh 

[bhobba]

Aha, Bill,

My serious mistake.....  you meant the VSonics, I was thinking of Big Ben......

I do it all the time.  Don't worry about it.  Cant wait to hear about that new speaker though.

The VSonics have been reworked for the Scanspeak H1288 8" woofer.   All future crossovers/enclosure design will be set up for this driver.

I think you are having one of thsoe days Hugh - I think that should be the Seas H1288.  Dont worry about it - I am having one of those lives 

Thanks
Bill

[AKSA]

Bill,

Dead bloody right you are, Sire, that's a SEAS......

Cor blimey   

I need my walk in the park.  Sadly it's raining.....

Hugh

[daredevil_kk]

Maybe I can give my 2 cent.

The new materials used for the cone can be quite good due to the stiffness to weight ratio giving it, it's fast and accurate bass, maybe sterile to some. But the main pain in using them is the ringing freq that they have. Designing and building a good crossover is difficult usually an notch filter or a 4th order filter is required.

But if you can tame the tiger, the results are fantastic.

Cheers,
KK 

[bhobba]

Maybe I can give my 2 cent.

The new materials used for the cone can be quite good due to the stiffness to weight ratio giving it, it's fast and accurate bass, maybe sterile to some. But the main pain in using them is the ringing freq that they have. Designing and building a good crossover is difficult usually an notch filter or a 4th order filter is required.

But if you can tame the tiger, the results are fantastic.

Cheers,
KK

I think its to some extent what you are used to.  Its usually the metal (and to some extent ceramic as used by Accuton) speakers that have the horrid breakup modes - the modern paper treated material like nomex etc still ok from that viewpoint and interestingly are very very close to metal etc from a distortion viewpoint.  Metal etc still has the edge but Nomex, Nextel etc is scary close.  Personally with how close it is I wouldn't worry about the breakup problems with the metal stuff and stick with the easier to use treated paper.  That said some very interesting metal drivers are appearing out of China eg:
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=290-218

Guys who have worked with it say its scary close to the best out there such as the Seas magnesium and Accuton.  They still have the edge but now its so close some designers have no qualms pairing with with very high end components such as the RAAL 70-20 ribbon to make a fantastic product at a drop dead price eg:
http://www.audiocircle.com/index.php?topic=76365.0

For what its worth I am much more attracted to that approach than I ma to the cost is no object approach. 

Thanks
Bill

[Tliner]

Hi All,

The replacement driver for  "BEN" will be a yet to be released aluminium coned 12" woofer made by a highly respected European manufacturer. This metal coned driver should not exhibit the dreaded "metallic sheen" as it will work below 180 Hz, well below the metallic induced spike. Which is at about 3000 Hz.  This driver will fit exactly in the same hole and even the screw holes as the defunct Peerless 830847 driver. The moving  mass for the new driver is 119 grammes, giving a saving of about 44 grammes which makes for a faster responding driver. A woofer from SBAcoustics was concidered but it is 38 mm larger in diameter and won't fit in the box as designed. The only change may be to the positioning and weight/density of the stuffing.

When we auditioned drivers for the VSonics we found that no matter what tricks were tried a plastic coned driver it still sounded plastic. Similarly with metal coned drivers.

Don't forget that as we become older our hearing drops off in the upper registers. Friends who have worked in noisy industrial places simply love metalic drives because to them as these drivers deliver a "cleaner, clearer" sound for them. Obviously the metalic coned driver compensates their hearing loss somehow.

I suppose that there are horses for courses!

Have fun,

Cheers,

Laurie
   

[bhobba]

Don't forget that as we become older our hearing drops off in the upper registers. Friends who have worked in noisy industrial places simply love metalic drives because to them as these drivers deliver a "cleaner, clearer" sound for them. Obviously the metalic coned driver compensates their hearing loss somehow.

I think there is something in that.  I never worked in industrial environments nor listened to HI Fi at loud levels. It is an unappreciated fact that if you listen for extended periods over 90db it can and will lead to damage.

My friend in Canberra does not like metal speakers - he much prefers paper cones.  I am pretty ambivalent I must say - either is fine for me.  From a design viewpoint those horrid breakup modes must be murder to handle which is why I would shy away from them.  Sure on the basis of distortion measurements they have an edge - but distortion is not the only thing and other materials are scary close anyway.

Thanks
Bill

[daredevil_kk]

That is when active crossover come in play. A cheap but very good high order crossover can be easily achive. Of course it requires you to bi-amp, but you will be also enjoying all the benefits of bi-amping

KK

[Tliner]

In front of me right now I have an aluminium, ABS (plastic), Nomex and a paper coned driver and I am very gently tapping the cones with a pencil, just letting the pencil bounce under its own weight while holding it at the other end. I can easily hear a metallic ring (sound), a palstic sound (like tapping a plastic drink bottle) and a fairly neutral sound of both the Nomex and paper coned drivers.
Once you identify the particular sounds the different materals make you can from the back of a listening room identify the material a driver is made from. Personally I don't like music with a metallic or plastic bloom to it. No matter what crossover is employed you can't eliminate the inherent sound of the material. Where as "natural fibres" (Nomex is made from hemp fibres and can be bonded with a variety resins depending on the end use) including paper don't add much if anything to the "sound". But to make paper reatively stiff and hard wearing a variety of resins are used to achieve the desired result sometimes at the expense of weight. Very generally metal cones are lighter than resin saturated ones as there is less energy required to to move the cone, ideally as fast as the strings or reed of an instrument move, there by replicating the origional note in all its glory. But as said before, IMHO there is a down side to plastic and metal coned drivers.

Once you hear the sounds of the materials used in a drivers cone you will know exactly what I mean. Hearing is believing!

Cheers,

Laurie   

[Rhythm Willie]

Tliner,

Depends on what sort of metal or plastic is used as there are hundreds of different materials and alloys.

Just tried the pencil experiment with the Seas Excel Magnesium and paper drivers in my speakers and the magnesium ones are "deader".

[Tliner]

Yep RW,

Your are correct. Magnesum has a inherently deader sound particularly when compared to Aluminium. And that all depends on the grade/temper of the metal. If the metal in a cone is too thin and or soft they will eventually fail.  Even some metal cones are thicker at the voice coil and thinner at the surround. I presume that tapering would break up "the sound" too. I have made some resin transfer moulded speaker cones with the optimum fibre/glass ratio of 68% carbon and 32% resin. There were no voids in the matrix. The cones were unburstable and light as paper but the sound was horrific. Obviously the resin was too hard, ringing like glass when the pencil test was applied.

It is more economical and satisfying to use a appropriate commercially manufactured driver.

have fun,

Cheers,

Laurie