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From: sher@bbn.com (Lawrence D. Sher)
Newsgroups: sci.electronics
Subject: Sony, are you listening?
Keywords: Sony, TV, volume, headphones
Message-ID: <59154@bbn.BBN.COM>
Date: 27 Aug 90 12:19:56 GMT
Sender: news@bbn.com
Reply-To: sher@BBN.COM (Lawrence D. Sher)
Organization: Bolt Beranek and Newman Inc., Cambridge MA
Lines: 33

I have a new Sony Stereo TV (Model 20TX11).  On the back are
  a) 2 RCA phono plugs labeled "Audio Output (Variable)" for R and L channels
  b) a "Speaker On/off" switch
  c) no "Headphones" output

With the TV's speaker shut off and stereo headphones (Sony Model MDRS101
II) plugged into the R and L channel outputs for private listening, the
audio volume is very low, although usable if the TV volume is cranked
way up (80-90% of maximum in a quiet room).

Sony's customer assistance line ((800) 222 SONY) says "You can't use
headphones with that TV."  (Hard to believe, isn't it.)

The problem appears to be the mismatch between the TV's output impedance
(manual says 10k ohms) vs the headphones' probably-much-lower input
impedance (like 32 ohms).  I've tried other headphones; the results are
expectedly similar.

Questions:
    1. Will I damage the TV by running it with the volume cranked way up
       and the internal speakers shut off?
    2. Are there any modestly priced headphones that *would* be suitable?
    3. Is there a simple fix?  (Buying a stereo amp just to drive
       the headphones seems crazy as well as expensive.)

Your help is very much appreciated.


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