Tweeter Quest

Hi,

While you are of course perfectly welcome to believe what you like, the fallacy of this believe is easily illustrated. Make three different shapes from the same material, eg one set metal, one set plastic and one set cardboard. Then proceed to strike any of them with a suitable object, like a biro.

Despite the different shapes, the same material will have in subjective terms a sameness to the tone, on top of the different resonance frequencies the different shapes and sizes introduce, while identical shapes made from different materials will sound notably different.

The issues are related to such issues like speed of sound in the material and the materials lossiness and so on. As these are fundamental properties of the material on elementary levels they can only be changed by layering the materials or making (for want of a better word) alloys or other blended combinations.

This a view commonly promoted by the objectivists, who believe that:

A) If something is measured, it actually matters

and

B) that all that matters is being measured

and

c) that if all that matters is measured and that is measured matters what measures the same MUST the same.

The spikey and buzzing realm of reality however refuses to conform to this pixelated cardindexer viewpoint and continues to defy the requirements of the objectivist....

The mangers diaphragm and voicecoil former is NOT metal. It is actually nowadays a composite layered plastic, IIRC what Ms. Manger told me, early versions used pantyhose that was for want of a better word rubberised (basically a huge and flattened out softdome tweeter).

The key is a high internal loss and damping of the material which allows the mangers diaphragm to operate in what is permanet breakup without too many severe resonance modes, in fact again analogous to the way in which softdomes work and in opposition to the rigid piston principle commonly claimed to be the best solution for transducers.

Ciao T

 

Like I said, if it were a metal cone woofer and a metal dome tweeter I think that has some merit but when the design is very different (not just a different shape), I think it’s another story. A dome mid and a ribbon tweeter are very different in the way they actually work so I don't think it matters too much what material its made of.

Anyway, I think its not as much the material itself 'sounding' but the characteristics of the driver which certain materials allow you to achieve. Metal is light and stiff so it sounds fast and lively but you could maybe do the same with carbon for example. I agree the actual material pays a roll but to a much lesser degree I feel.

You see to me, ribbon tweeters 'sound like metal' in as much as they are very very fast and don't dull the high frequencies much, but if you take an isoplanar they can sound the same in that respect, despite being made mainly of plastic film. They are fast and don't dull the highs... to me they sound like metal as much as an aluminium ribbon I'm afraid!

Maybe what I associate with different materials sounds is not the same as you.

I thought I read that the Manger diaphragm is a variable thickness steel plate but now I read up on it you are right, they call it a specially developed three-layer material.

 

Nick, I can't believe that you would consider butchering those speakers - they cost a fortune!

Clean sheet design gets my vote.

 

T(HD) wipe ya mouth.

You've got to be the biggest joke on the net, your nothing but a rubber chicken of the very worst kind.

http://www.zaphaudio.com/nondomes/

A cheap Vifa unit beat the lot. There's no wonder you've love ribbons T(HD). They've got a lovely distortion profile that matches the rest of your system. But of course, distortion is baad in your book.

Folks like Tony Gee, John Krutke, Troels and ScottG have forgotten more than you'll ever know about loudspeaker design and they also offer a balanced viewpoint on design.

 

Well just a tweeter swap - totally reversible

Materials do have immutable physical characteristics however it will depend on physical dimensions, shape, how it is being driven and damped etc. Does a metal flute sound metalic? Can an organic violin never sound harsh? Suitable application of ingenuity can solve (almost) any problem. In its absence certain fundamental characteristics will assert themselves. I think both sides have a point here.

 

Shin,

Your quote of Thorsten made me laugh! However, I think you are a bit harsh on Thorsten! He is a VERY helpful guy and just expresses his views. I don't think he said ribbons are particularly low distortion. Your jabs are pretty funny, but ease up a bit 'eh?

By the way my black finish is coming along! Layer after layer of lacquer going on! The bloody filler I used in the small join gaps was not as smooth as I thought it was though! Ahhh! Don't use caulk when you have run out of proper pollyfiller! (the powder stuff you mix with water)

 

Hi,

You might try washing yours out.

Surely you are projecting your own hangups and insecurities at others?.... I'm neither chicken nor rubber, as you could find out if you said things like that to my face....

I do not what Zaph has been measuring and how, the measurements found in Klang + Ton and Hobby HiFi look certainly very different.

Anyway, what means "beats"?

The Isoplanar I use manages easily around 0.1% 2nd HD and less 3rd HD at 95db/1m. In fact, the distortion measurements made by Canadian NRC, a much trustworthy body in my view of a Speaker using the same isoplanar I use look like this:

(from: http://www.soundstagemagazine.com/measurements/ascendo_z_f3/)



This is the THD at 95db/2m, in other words 101db/1m!

For comparinson here a "beats everything" Vifa Tweeter as used in the PMC GB1:

(from: http://www.soundstagemagazine.com/measurements/pmc_gb1/)



The "beats everything" tweeter has over 6% (-24db) THD at high frequencies for identical SPL against the "horribly distorted" isplanar drivers unde r1% THD at the same frequncies and SPL's.

Obviously. And it should be equally obvious why YOU love the Vifa Dome (BTW, the ring radiator is worse, I also have measurements from K+T to illustrate that, but never mind, it still looks way clean next to that ATC Midrange dome, so what, if you like it there is no arguing with that)....

Yup, well spotted. Of course, in my system as it is now, the speakers are still the highest distortion device, still, what is there is jolly low, for speakers anyway.

Anyway, nice talking to you, but forgive me for adding you to my ignore list (you will be in august company), as I have no more time to waste with you.

L8er T

 

Join the club ShinOBIWAN - those who dare to disagree with the one hiding behind the mask of T for Totalnutter

 

Is the atc a bit messy looking? Somehow I am not surprised given the aching in my ears.

The ribbon in your design sounded pretty clean and with a benevolent low-distortion signature to my ears - its efficacy should be obvious in my reaction since that time!

 

Total and utter cobblers!

Why the stupid attacks?

I've only met T once and got the impression that he'd gladly assist anyone to achieve better results from their system, freely giving advice and passing on his knowledge - gratis.

Disagreement is one thing but you do yourself no favours with the attitude you adopt.

 

I think given the choice between any other ribbon and a planar like Thorsten's Hi-Vi I would choose the planar. Its only the Raal that I think will match it and perhaps better it in subjective terms.

Edit: Just to put some figures on that, the Raal's impulse response is done and over before 3.1ms and the cumulative spectra decay shows practically nothing beyond 0.2ms even at 2KHz. The THD is slightly higher than the planar but I believe THD is over rated as long as it is within very low levels anyway.

I can't actually read the THD graph from Raal, it has 1% in the middle then below, it goes 562.3m, 316.2m, 177.8m and so on.. whats that mean?!

 

The guy deserves no quarter. He's one of the worst kinds of self confessed rubber chicken - one that offers only his own preferences. If offering help is biased information based on personal preference and misleading or plain false information, then I wouldn't want help.

He should stick to electronics because I can clearly see a lot of talent there. His views on loudspeaker and driver design are completely valid but its just another take on a very long line of opinions. What makes him an easy target is his statement of fact based on opinions and his somewhat do what I say not what I do approach. There's also the fact that other choices that don't agree with his own are put down, when in actuality there's a good chance they're actually superior.

Blinkered through self-importance and personal opinion would be the best way of describing T(HD)'s comments on loudspeaker design. Sure they're valid like anything else but are they as right as he would have you believe? Absolutely not.

Sounds good

I sent you a good few sheets of 3M on the way home from work. The Bonda 2part woodfiller is great stuff - very smooth finish and doesn't shrink like other fillers. Or alternatively car body filler works well.

How much laquer have you laid down so far?

You'll have to send some pics or post in the DIYA thread. If you need a second opinion give us a shout and I'll try to help out.

 

So far I have put two very thick coats on, but have more to go. I'm aiming at 5. I'll probably give up at more like 4 though!

 

Respectfully,

I'm not arguing with you. And likewise I'm not questioning T(HD) generosity in 'information' sharing. Clearly Thorsten has folks who agree and wholeheartedly endorse his viewpoints, are these the enlightened few who can only achieve a 'true reference' through his teachings as he would have you believe? And likewise, there's also a lot of folks who disagree with his views in loudspeaker design, perhaps being a minority forced a viewpoint that narrows in perspective compared to well rounded and more knowledgable loudspeaker designers.

One area where I wouldn't question T(HD) is electronics but I've built, designed, measured, researched and listened to enough loudspeakers to know ignorance when I see it.

 

No, but your attitude stinks mate.

Describing someone as the 'biggest joke on the net' is below the belt.

 

Well thats a bit unfair. I have had quite a bit of helpful advice from T and he always deals with topics objectively even if he does state his own preferences as well. On a number of occasions he has pointed me in the direction of things he thinks I will like even if they are not to his taste. He always respects others "tastes" at the same time as providing an interesting viewpoint and valuable knowledge and he does so whilst keeping an open mind and without descending into the usual antics on forums. I have never once seen him put anyone down. For that I think he deserves a little bit more respect as one of the most valuable members of this community. Even though many of my audio preferences are diametrically opposed to his and I dont agree with all of his views he has always been a gent in our discussions.

 

The biggest joke on the net are linn + naim + atc + mana owners everyone knows that

 

I'm guessing you've only heard the ATC mid in an ATC speaker? All respect to ATC but they don't use it to its potential. The FR in particularly is rough at best and it has anomolies that need to be avoided.

Look here:





There's clearly issues with ATC's take on things, for starters they don't implement any FR smoothing in their active or passive versions - see Stereophile's review of the SCM70's. The ATC mid sounds more coherent and 'right' after the response has been flattened to +/-0.5dB through out its passband. I also think they cross the mid too high/too shallow slopes because there's a nasty resonance at 4.5Khz when they're crossing at 3.5Khz 24dB/Oct, this is clearly audible from my listening test and lends an unpleasant hardness to the sound that over shadows softer detail. I cross at 3.2Khz with 96dB/oct slopes and that offers a much less hyped sound and a more realistic, balanced and easy going listen.

ATC also have the same sort of views on cabinet construction as when they formed. I put considerable effort into minimising the cabinets contribution to the sound. Again this aid things in ways that really make the notion of listening to a box very nearly dissappear.

I've heard the SCM50 30th Anniversary and my own take is much smoother with better insight and very coherent/natural imaging thanks to superb phase response and time alignment - something the ATC don't do well after looking at measurements. Overall the two speakers sound and measure very differently.

Much of the reputation of the ATC mid from the naysayers is actually based on a flawed implemention or rather one that isn't using everything the driver has to give.

Come listen to my implemention and have some sauce to go with that hat.

 

I appologise for the gross exageration and rudeness, it didn't help. I'm not out to make enemies but I'm voicing my opinions on T(HD)'s self rightiousness. Obviously some will agree and some will disagree with that.

 

How low do you cross them Shin? Anyone got THD measurements on the ATC mid?

One thing is for sure, Thorsten is Marmite!