Re: 3 dB bandwidth


Adrian Tuddenham wrote:

> Kevin Aylward <see_website@xxxxxxxxxxxxx> wrote:
>
> > There is simply no bloody law that says Bell labs original definitions
> > mean anything at all. "I don't need to stinking Bell labs" to tell me
> > what is a correct definition. Today, Bell labs are wrong.
>
> That's an interesting approach to a scientific/engineering subject.
>
> But you should save all that vehemence for when you will really need it:
> ... to convince an irate customer and the Trading Standards authorities
> that your product is fine because it meets your definition of electrical
> units, even though it obviously doesn't meet theirs.

Bell Labs definition is *not* the standard. Trading Standards would laugh at
an attempt to refer to it.

The standard is set by the AES. They even introduced the dBu ( voltage
reference unit = 0.775 V ) to replace the dBm ( 600ohms ) so that modern
voltage matched audio circuits could be correctly specified without having to
refer to a trashy old power-impedance related unit.

Do you perhaps also think that all audio is still done with toobs ?

Now grow up and read some *new* books !

Graham

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