nuckolls.bob(at)aeroelect
Guest
|
 Posted: Tue Oct 04, 2011 6:37 am Post subject: Audio systems and "output impedance" |
 |
|
At 10:53 PM 10/3/2011, a reader wrote:
| Quote: | Bob, the audio out on this beast is rated at 500 ohms. I don't
think my Bose headsets are the same? What's the best way of tying
this into my audio system, I have a cheap aviar intercom I was
planning on using but open to suggestions? I also have your Audio
Isolation amplifier.
|
See the description of audio systems and the concept
of 'output impedance' in the audio chapter of The
Connection.
There's not a single audio device with a real
output impedance of 500 ohms . . . or any
similar value.
By definition, a source of energy with an output
impedance of 500 ohms would see a drop in output
by 50% when loaded with a 500 ohm headset. Two
such headsets in parallel would drop the output
further to 33%.
So when an audio output is 'rated' for 100 mW
into 500 ohms, they're only speaking to the
ability of the amplifier to deliver a VOLTAGE
along with a citation as to POWER delivered
into a typical load. Interestingly enough, the
same output, when presented with TWO headsets
of load would deliver 200 mW.
My audio isolation amplifier has an output
impedance of less than 1 ohm . . . but it's
capable of delivering about 8 volts pk-pk into
what ever load you wish to tie onto it. The
smaller the resistance . . . the higher the
current . . . the higher the power.
Further, because the true output impedance is
so low, you can drive 1, 2 or 10 headsets with
no perceivable drop in ouput.
Your radio(s) and intercom are similarly configured.
Just know that the term "output impedance" is
quite often used in a manner that does not
contribute to understanding.
Bob . . .
Bob . . .
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
Get Email Distribution Too!
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
