[TenTec] Best Headphones?

[RaySoifer@cs.com]

In a message dated 12/27/05 7:26:19 PM GMT Standard Time, 
jkelly at bellatlantic.net writes: 
> Just to mention that they are listed at 14.99 but
> they rang up at 9.99 in my Manasquan, NJ store.
> 

The same thing happened here in Tucson.  The TDE headphones were marked 14.99 
but they rang up 9.99 at the register.  I had to go to two CVS stores, 
though: the first one didn't have them.

I tried them on my Argonaut V, which has only mono audio, but even there they 
reduced external noise, e.g., from the fan.  When my Orion II comes, 
hopefully later this week, I'll try them out on binaural CW.

Many thanks to Bill for bringing these cheap noise-cancelling headphones to 
our attention.  BTW, Prof. Bose also tried to teach me introductory circuit 
theory, but he obviously had more success with Bill :-)

On another subject, S/N ratios and filter bandwidths: some years ago Joe 
Reisert, W1JR, wrote in Ham Radio magazine about experiments that were done by the 
Signal Corps during WW II.  They found that the effective bandwidth of the 
human ear/brain combo, when copying CW, is a function of the audio frequency of 
the desired signal.  The narrowest bandwidth was found to be approximately 50 
Hz, at an audio frequency of approximately 400 Hz.  The ear's bandwidth widens 
as the audio frequency is raised.  I don't have Joe's article in electronic 
form, nor is the hard copy easily at hand (it's buried somewhere in the stuff I 
brought with me when I moved QTH), but if you have the old issues of HR, it 
was in the Aug/Sept 1987 issue.

73,

Ray W2RS