Roger

There are plenty of old ex Marine es Military headphones about that are suitable. 2000 ohms was a common imp for the older headphones. S G BROWN was a common make in the past plus a variety of others. Old GPO ear pieces would also suit your requirements. 

More recent communications headphones are around 600 ohms.

Old Crystal sets with a good set of high Z headphones and a decent antenna like an inv L produced good results, plenty of volume on MF es LF

mal/g3kev

 

----- Original Message -----

From: Roger Lapthorn

To: [email protected]

Sent: Friday, January 27, 2012 10:29 PM

Subject: LF: OT: Headphones

Slightly OT but people like Mal and Jim may have an answer.

Is there a "modern" (i.e. can you buy it new today?) headphone set that is extremely sensitive in the same way that the old DLR5 headsets were in terms of efficiency converting AF to sound pressure in the ear? 

I believe Jim M0BMU claimed 2uV audio power could be heard using DLR5 headsets in his passive mechanical SAQ receiver. As DLR5s are more difficult to find these days I was wondering if there is anything as sensitive, or more so, around "new".

73s
Roger G3XBM

--
http://qss2.blogspot.com/
http://g3xbm-qrp.blogspot.com/
http://www.g3xbm.co.uk
https://sites.google.com/site/sub9khz/