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"Jeg hører ex. soft domer som støj"
Meget interessant - mest for dig, Tadman, for der er sørme ingen andre, der skærer alle softdomer over en kam. Hvis det skal være, er der til gengæld andre, der er kede af det ultrasoniske peak på metaldomer. Personligt lytter jeg fra gang til gang.
"...har en lidt reserveret mellemtone, da denne er lavet af magnesium"
Igen en interessant, men udokumenteret slutning.
"Tænk på, at der ikke er noget svingspole gab til at holde fast i membranen - når først du sætter det i gang, så stopper det altså ikke bare lige sådan"
Ups, Tadman, du glemte den associerede luftmasse. Det er den, der varetager dæmpningen i et bånd, ligesom ved en elektrostat. Og jo, de stopper. Hurtigere end nogen anden elektrodynamisk enhed. Læs dog en bog!
Her er lidt læsestof, til dig som virkelig er sagkyndig hinsides ht - så vågn da op fra din forestilling om metal er metal...
Mr. Be
Name: Beryllium
Symbol: Be
Atomic Number: 4
Atomic Mass: 9.012182 amu
Melting Point: 1278.0 °C (1551.15 °K, 2332.4 °F)
Boiling Point: 2970.0 °C (3243.15 °K, 5378.0 °F)
Number of Protons/Electrons: 4
Number of Neutrons: 5
Classification: Alkaline Earth
Crystal Structure: Hexagonal
Density @ 293 K: 1.8477 g/cm 3
Color: gray
| Isotope |
Half Life |
| Be-7 |
53.3 days |
| Be-9 |
Stable |
| Be-10 |
2600000.0 years |
Date of Discovery: 1798
Discoverer: Fredrich Wohler
Name Origin: From the mineral beryl
Uses: spacecraft, missiles, aircraft
Obtained From: beryl, chrysoberyl
History
(Gr. beryllos, beryl; also called Glucinium or Glucinum, Gr. glykys, sweet) Discovered as the oxide by Vauquelin in beryl and in emeralds in 1798. The metal was isolated in 1828 by Wohler and by Bussy independently by the action of potassium on beryllium chloride. Beryllium is found in some 30 mineral species, the most important of which are bertrandite, beryl, chrysoberyl, and phenacite. Aquamarine and emerald are precious forms of beryl. Beryl and bertrandite are the most important commercial sources of the element and its compounds. Most of the metal is now prepared by reducing beryllium fluoride with magnesium metal. Beryllium metal did not become readily available to industry until 1957. The metal, steel gray in color, has many desirable properties. It is one of the lightest of all metals, and has one of the highest melting points of the light metals. Its modulus of elasticity is about one third greater than that of steel. It resists attack by concentrated nitric acid, has excellent thermal conductivity, and is nonmagnetic. It has a high permeability to X-rays and when bombarded by alpha particles, as from radium or polonium, neutrons are produced in the amount of about 30 neutrons/million alpha particles. At ordinary temperatures beryllium resists oxidation in air, although its ability to scratch glass is probably due to the formation of a thin layer of the oxide. Beryllium is used as an alloying agent in producing beryllium copper which is extensively used for springs, electrical contacts, spot-welding electrodes, and nonsparking tools. It has found application as a structural material for high-speed aircraft, missiles, spacecraft, and communication satellites. It is being used in the windshield frame, brake discs, support beams, and other structural components of the space shuttle. Because beryllium is relatively transparent to X-rays, ultra-thin Be-foil is finding use in X-ray lithography for reproduction of microminiature integrated circuits. Beryllium is used in nuclear reactors as a reflector or moderator for it has a low thermal neutron absorption cross section. It is used in gyroscopes, computer parts, and instruments where lightness, stiffness, and dimensional stability are required. The oxide has a very high melting po9int and is also used in nuclear work and ceramic applications. Beryllium and its salts are toxic and should be handled with the greatest of care. Beryllium and its compounds should not be tasted to verify the sweetish nature of beryllium (as did early experimenters). The metal, its alloys, and its salts can be handled if certain work codes are observed, but no attempt should be made to work with beryllium before becoming familiar with proper safeguards.
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Emne: højtalere til 30-40.000kr
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av, den sved, Tadpole! Som jeg skrev, er jeg ikke modstander af nogen type domemateriale på forhånd. Og Be er naturligvis et glimrende materiale, det er der ingen tvivl om. Men spar os venligst fra "alle andre end jeg vandrer i mørke"-spærreild. Hvis du ikke forstår, hvordan folien i en elektrostat eller i en bånddiskant dæmpes af den koblede luftmasse, så tjek det inden du taler om manglende dæmpning. Og husk, at vi begge er enige om at Pioneer-modellen er et godt, omend lidt dyrt valg ift. udgangspunktet - de kan vist ikke fås på 40.000..
men hold da helt op de spiller musik.Og en helt utrolig bund
har faktisk haft nogle henvendelser på mine strausser, hvor folk havde BKS som de ville bytte med. Dene ene var den høje satan på 180cm 
