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Re: 20dBPad

PostPosted: Mon May 23, 2011 2:41 pm
by Mathieu Benoit
macrae11 wrote:Yeah I totally understand it now, just that most places it's taught, it's still shown at I=V/R. As in all the places that I learned it before here.

I seems strange that they'd bother using "I" in that case though. I mean when not "C" for current, if they are going to use "V" for voltage. I'd actually understand C=V/R, but to mismatch what the letters represents makes my OCD senses tingle.

macrae11 wrote: Not that it will probably make any practical difference in my life... ever.

That's the spirit, now Alain will be less inclined to bother explaining it next time. :roll:

Re: 20dBPad

PostPosted: Mon May 23, 2011 2:50 pm
by Mathieu Benoit
Here's an interesting bit of trivia:

Internet wrote:The conventional symbol for current is I, which may seem puzzling. It originates from the French phrase intensité de courant, or in English current intensity. This phrase is frequently used when discussing the value of an electric current, especially in older texts; modern practice often shortens this to simply current but current intensity is still used in many recent textbooks. The I symbol was used by André-Marie Ampère himself, after whom the unit of electric current is named, in formulating the eponymous Ampère's force law which he discovered in 1820. The notation travelled from France to England where it became standard, although at least one journal did not change from using C to I until 1896.

Re: 20dBPad

PostPosted: Mon May 23, 2011 2:53 pm
by Alain Benoit
Mathieu Benoit wrote:
macrae11 wrote:Yeah I totally understand it now, just that most places it's taught, it's still shown at I=V/R. As in all the places that I learned it before here.

I seems strange that they'd bother using "I" in that case though. I mean when not "C" for current, if they are going to use "V" for voltage. I'd actually understand C=V/R, but to mismatch what the letters represents makes my OCD senses tingle.



Because C is for capacitance, the unit for which is Farad. Also C is for coulomb, a unit being the product of both time and current.

Re: 20dBPad

PostPosted: Mon May 23, 2011 3:16 pm
by Alain Benoit
Jef wrote:Can these be used in tandem, I mean like plugging one into another one? and if so, is the gain reduction of each added together? For instance if a 10db gets plugged into a 20db will the total gain reduction be 30db? I was thinking about building a few of these for my own tool kit and I could probably get by with just a few different sizes if this is the case.

The construction looks easy enough, but I don't know the math involved in determining the size of the resisters per/gain reduction. Any help for a do-it-yourselfer?


1) Yes they are additive.

2) Google "H Pad calculator" or "T Pad calculator" .

Re: 20dBPad

PostPosted: Fri Jun 08, 2012 3:43 pm
by sean.boyer
Wow! What's the part # for those XLR barrels? Those are great! Pads, phase reverse, phantom blocker... The applications for those are endless! I want some!

Re: 20dBPad

PostPosted: Fri Jun 08, 2012 4:45 pm
by Alain Benoit