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Old 7th February 2013, 02:53 AM   #34351
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Originally Posted by john curl View Post
We have often found that German/Swiss standards of mechanical perfection higher than typical American standards.
Europe was not so rich than US, so, we were obliged to use as little raw (import) material as we could. This obliged-us to have very good steel and advanced technology etc. While US used to oversize everything, with quality of the materials way under. At the end, with resource reductions, the US had joined the same technology we used in Europa, with little light cars, good quality and finish, good breaks and good road holding. The result is we buy some American cars in Europa, now, while it was no way in the 60/70s apart some for the look, like Ford Mustang.

About actual overall quality, we are now all on the same level all over the world: planned obsolescence in a little planet.

About audio, the major problem is the size of the market: Hifi for the few in little countries. Public audio is mainly highly industrialized Japanese, nowadays, except for stuff not industrial, like loudspeaker's baffles. And for those, Europa is not so bad on the market (Cabasse and Focal for France, as an example).
Last, in France we were absolutely not aware of business, commercial and export. A country of artisans. Now we copy US business with ten years late, and the result is our lives have become hell.
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Last edited by Esperado; 7th February 2013 at 03:12 AM.
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Old 7th February 2013, 03:09 AM   #34352
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Christophe,
I understand what you are saying about touring sound systems and the difficulty with sound checks and getting the sound correct in so many different venues. You never know what you are going to have to deal with. It could be indoors one night and outdoors another and these are very different situations to deal. Then you have the size of the venue to deal with, one very large and a bowl and another small and intimate clubs with some good acoustics and others that are more of an echo chamber than anything else. On the other hand if you got to work with a fixed installation then you had the time and hopefully the equipment to get things right over time. Some of the best sound are these fixed installations. I know that you have been in all of these situations and can appreciate the difficulty of the constant changes from place to place. Same thing goes for the engineer who has to work in different facilities with different monitors and electronics, you don't know what you are going to walk into and what you will be able to accomplish with all the changes. I guess that today with digital recording it may be a bit easier to get the basic tracks down and then take them somewhere that you can do a final mix on equipment that you know and understand.
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Old 7th February 2013, 03:32 AM   #34353
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Live recording is an other stuff. We used big trucks with a real comfortable studio inside, big mixing desk, in the street or parkings, far away from the stage. As the musicians know they are recorded, and that is important for them, sometimes more than the public performance itself, they agree to have less feedback and more rehearsals.
That makes often the best sound for the audience, and, in the same time the best records, as it brings better conditions, and the real excitement and atmosphere brought by the public. Too, the musicians play together, not always the case in studio recordings. This make the music true and 'living' as each musician react in function of the other's play. This does not prevent to re-record some parts in studio after the show and before mixing, to correct errors, or try to get better singer's parts, or better solos, as an example, but the basis is there.
Too, with the use of 'rythm boxes', they can play the same tunes at the same exact tempos several days, so we can mix parts of the same tunes from different days, sometimes.
Of course everything is recorded with close miking, so the "room" is artificially recreated during the mix.
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Last edited by Esperado; 7th February 2013 at 03:43 AM.
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Old 7th February 2013, 03:40 AM   #34354
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Just out of curiosity what type of plastic did you use for the suspension? TAD uses the beryllium itself but to try and get down to 2.5Khz I feel will not be practical for that much excursion.
It was a thermoplastic material which we were alerted to by Heco, who were also part of Rank in those days.

Hostaphan variant springs to mind but that can't be right cos that's Mylar. Excuse my senile memory but it was more than 20 yrs ago.

Using Be for the suspension is a no no. I'm surprised Andy Jones even considered it. The surround provides the only damping except for a miniscule amount from the air load.

If you are only making a few, the woven fabric surrounds used by many manufacturers today for soft domes are worth trying but need to have damping applied. Liquid latex dissolved in ?? is as good as anything more sophisticated. However, this type of surround construction isn't really appropriate for consistent production.

The material we used is no longer made cos the EU regulations on WHS.

We had similar problems with surrounds for cone speakers cos the 'rubber' mixes available were always dictated by tyre manufacturers but then the quantities we used made it worthwhile to stockpile.

The Accuton page brings back many memories and I see they use a 'fabric' surround. Ferrofluid is important and they improved a lot over the period we used them.
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Old 7th February 2013, 03:57 AM   #34355
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Look at JBL now run by marketers and accountants rather than engineers, their classic products and engineering drive of the 50s through the 80s gone, except for their top of the line Japanese export market product , has lost it's soul. Closed up shop in California and now just a brand name to sell more Chinese and Mexican produced lo and mid fi. Looks good on a balance sheet somewhere.

http://audioheritage.org/

Last edited by ticknpop; 7th February 2013 at 04:13 AM.
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Old 7th February 2013, 03:58 AM   #34356
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Finally, you make sense, Esperado. I have heard both bad and good sound from the same PA, and it is often bad luck with the acoustics at a particular venue.
You have to take very fast decision about the setting, in places you don't know, and with the heavy stuff involved and assembly time, it is a no way back.
When you realize you had made a mistake, it is too late, you have to do with it.
Worse, when you decide the set-up, the theater is empty: acoustic change a lot with the audience (good damping material) in a way difficult to guess.
And so many unexpected incidents and disasters from outside or your own stuffs , you have to get around instant with no room for error!
I would not have the courage today to take such risks and such responsibilities, it is scary and exhausting.
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Last edited by Esperado; 7th February 2013 at 04:03 AM.
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Old 7th February 2013, 04:10 AM   #34357
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Kgrlee,
Thanks for the information. Yes I agree about the damping of a metallic surround and especially one where there is no discontinuity between the surround and the dome. I am looking at using a thermoplastic urethane surround for the specific reasons that you sighted. I am looking at serial production so I do not want to deal with doping a cloth surround, as you say to inconsistent for production. The adhesive used at the joint is just as important as the surround itself and so many make the mistake of using a rigid adhesive like a CA and then we are right back to having a reflective material sending vibration directly back to the dome before the surround can even attenuate those vibrations. As you learned most of the butyl rubber or natural rubber compounds also have poor damping properties. I would think the same about the mylar suspensions. I know some companies use that material as a surround for there compression driver surrounds but there we are looking at extremely low excursion and I know that it can be the cause of some nasty noise production. Thanks for trying to jog your memory. The beach can do that to you!
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Old 7th February 2013, 04:25 AM   #34358
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ticknpop,
I can attest to the fact that JBL was a stickler for products heading to Japan. I did contract work for them, including development, tooling design and manufacturing, on their highest end product at one time that was destined for Japan. If there was the tiniest flaw that you had to go out into the sun and look for they would reject a product. It was insane but we did meet the requirements. Even then most of their products were being made in the orient except for the pro-audio devices. This was all done with the Northridge facility on Balboa Blvd. But even then the quality of what was done in-house was shoddy some times, this was during the time that Harmon was out of Sidney Harmon's hands and the company was run by a bunch of MBA's as you said. I forget who owned them at the time but I want to say it was a large food conglomerate. They were a mess.
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Old 7th February 2013, 04:29 AM   #34359
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Christophe,
One of the problems that I remember doing concert sound in different venues was the ac power source. Some places would have enough power, others would blow breakers and have nothing but noisy ac sources. How many times did we have to bring in portable power generation to separate the audio from the house power and especially the lighting systems. The more you make me remember the more I want to forget.
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Old 7th February 2013, 04:54 AM   #34360
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JBl and HK was owned by Beatrice Foods.
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