[CQ-Contest] LOUD cans

[Mark Steven Williams]

Steve,

I am careful but probably run 'em a little too hot when I'm on the broadcast radio. After 44 years in broadcasting and 25 years as a ham I still have most of my hearing...save some high frequency loss. Probably the more damaging factor as far as my hearing is the Ohio Valley weather. I occasionally have severe sinus and inter-ear problems...and an occasional bout with labrynthitis...which is NOT fun.

Probably the most outrageous case of "headphone self abuse" I've ever seen was while I was still in L.A.back in the late '70's. A friend of mine was engineering KTNQ in Los Angeles. The "Real Don Steele" was doing afternoons and they installed a 200 watt Crown stereo power amp just to power his cans. Talk about making the ol' tympanic membranes bleed!

While we're on the subject of headphones and headphone systems I've been doing more experimenting with outboard headphone amps. The solutions posted by Tree and others are right on. An outboard amp, if configured properly, is an effective solution. Properly setting the gain structure is the key factor.

I have an older Timewave DSP 9 which has a decent audio amp. The "ideal" situation would be to drive this with the "fixed" "IHF line level" radio output. Problem with the DSP 9 is that it only has a "mono" input so splitting the main/sub rcvr audio or using the FT 1000s "diversity" receive function is impossible.

Currently I'm experimenting with some used broadcast headphone amps, a Rolls HP4 (if memory serves) and an Edcor "HA400". For starters I'm going to drive these from the radio's "phones" jack. Both the Rolls is pretty noisy..the Edcor a little better. I may try replacing caps and stiffening the power supply in the Edcor...or powering the Rolls with a gel cell. Once the s/n is satisfactory I'll drive the amp from the SO2R control box. Another option might be a Mackie or Beringer mixer...just use the headphone amp. I strongly believe that noise up in the "super audio" (16 khz and up) range, while imperceptible, can be a major cause of fatigue...especially over a contest weekend. Roll off everything above about 5 khz.

...and BTW, the Who was my favorite band starting way back...and who still apparently has most of his hearing and produces some of the best concert audio? (thanks in no small part to Bob Heil).... Joe Walsh!

73, Mark, K9GX

  ----- Original Message ----- 
  From: K7LXC at aol.com 
  To: cq-contest at contesting.com ; k9gx at n4gn.com 
  Sent: Wednesday, July 26, 2006 1:42 PM
  Subject: LOUD cans


  In a message dated 7/25/2006 9:02:08 A.M. Pacific Daylight Time, cq-contest-request at contesting.com writes:
    >  Everyone hears and processes audio differently.

    >  I must add here that I prefer the AUDIO HEADPHONE AMP in the 746, although
    there is some noise there. The 1000's headphone amp does not drive my Heil
    Proset to my liking. Professionally I am broadcaster and when I'm on the "3
    meter" band I like those cans LOUD.
          Ouch - please be careful. I suffered permanent hearing loss when I spent a year doing mortgage loans where I spent all day on the telephone with a one-eared Plantronics headset. I didn't realize that I had the volume turned up to unsafe levels until it was too late. LOUD isn't good. Ask Pete Townsend about it; he ruined his hearing the same way. 

  Cheers,
  Steve    K7LXC