Hey there, Dont misquote me, I didnt state that, someone else did. Seriously, jco
PS. I stated the 0dB marking was just arbitrary and the rest Of the dial was marked in dB for reference only to the Arbitrary 0dB marking. In reality an amplifer has a voltage Gain in dB at specific settings of the volume control dial. I would venture to say that at the marked 0dB setting there is actually A voltage gain of something on the order of 25 dB. What they Did was probably just mark the typical volume control setting as 0 dB Arbitrarily, and show all other "non-typical" settings of the Volume control in dB relative to that arbitrary 0 dB marking. The whole thing is nearly moot as most people just adjust the volume They want by ear and really couldnt care less about how many dB they Are changing the setting up or down. -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Ralf R. Radermacher Sent: Friday, February 03, 2012 7:06 PM To: Pentax-Discuss Mail List Subject: Re: OT question for electronics geeks JC OCONNELL <[email protected]> wrote: > Typically, 0 dB represents 1 mW (milliWatt). This is only the case with dBm where 0 dBm is indeed 1 mW across 600 Ohm, corresponding to a voltage of 0.775 V. dB with nothing behind expresses any kind of logarithmic ratio. Amplification, attenuation, signal-to-noise, whatever. You could define the price of a K-5 as 0 dB and then give the prices of all other cameras as plus (or minus) x dB. A camera costing +6 dB would be twice as expensive. -6 dB would be half price etc. Faders in studio equipment, e.g. mixing consoles, are usually labelled from minus infinity through 0 dB (the normal "open" position) to +15 dB. I suppose the manufacturer of the amplifier has put these dB values around the volume knob to make it look more professional. But don't take my word for it. I'm just a simple audio engineer. ;-) Ralf -- Ralf R. Radermacher - DL9KCG - Köln/Cologne, Germany Blog : http://the-real-fotoralf.blogspot.com Audio : http://aporee.org/maps/projects/fotoralf Web : http://www.fotoralf.de -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
