[TenTec] Headphones for ORION I?

[Dr. Gerald N. Johnson]

One solution I use for really noise free audio is posted at: 
http://www.geraldj.networkiowa.com/papers/speakerfilter.pdf This filter 
has selectable cut off frequencies and being passive and built for 
speaker impedance there is no high frequency noise introduced after it 
by 100 KHz bandwidth audio output ICs.

73, Jerry, K0CQ

On 8/12/2010 2:46 PM, Stuart Rohre wrote:
> Joe,
>
> You may want to read Rob Sherwood's web site on receiver and rig
> testing, about excess audio response.  He reports operators get tired
> listening to any audio above the voice or SSB, needed frequencies.
> In fact, you may want to put a band limiting filter in front of any hi
> fi headphones to avoid operator fatigue if you do much DX operating.
>
> That has also been our finding at the Acoustics research lab where I
> work for the Navy sonar folks.  Sonar operators need to only have the
> sonar frequency audible components and not a full span of ocean noise.
>
> 73,
> Stuart Rohre
> K5KVH
>
>