AudioNervosa

Systemic Development => Multiple Personality Disorders => Optometry Equipment => Topic started by: StereoNut on November 26, 2010, 09:40:33 AM

Title: Headphones & TV's...???
Post by: StereoNut on November 26, 2010, 09:40:33 AM
I hope everyone had a wonderful Thanksgiving.  Too much to eat and drink, for sure!  :-&

Anyway, I am looking to solve a dilemma in late night TV viewing in my household.  My son has a 3-4 year old CRT Hi-Def (720p, not that it matters for this) TV in his room, but there isn't any headphone jack.

How do I rig something up to allow him to listen with headphones from a TV that doesn't have an imput jack to do so?  Of course, I'm looking for an inexpensive solution as possible... and, no I am not a DIY'er that's going to open up the back of the TV and solder something into it!  8-[

Oh, his headphones have a 1/8" plug on them.  (If that's important or not?!?)

Thanks!
SN
Title: Re: Headphones & TV's...???
Post by: tmazz on November 26, 2010, 09:50:42 AM
If you , like many of us, have an old cassette deck laying around that you don't use anymore (I for one have not made a single cassette since I got a CD player in the car), try hooking the audio line outs from the TV to the record inputs on the cassette. put a blank tape into the deck and press record & pause. This will allow you to plug your headphones into the deck and use the record level controls to adjust the headphone volume. (Almost all home cassette decks were equipped to allow you to use headphones to monitor recordings, I am amusing yours is one of them.)

This will solve your problem with no cost outlay and allow you to use that old cassette deck for something other than a doorstop. :lol:
Title: Re: Headphones & TV's...???
Post by: richidoo on November 26, 2010, 12:11:19 PM
That's a good idea Tom.

There are a lot of cheap headphone amps available now too, most are battery powered for portability.  e.g. FiiO E3 on Amazon for $7. Someone probably makes an AC powered quality unit for more money. Late night TV watching is a popular sport.  I am going for world champion. :thumb:
Title: Re: Headphones & TV's...???
Post by: tmazz on November 26, 2010, 12:23:14 PM
That's a good idea Tom.

There are a lot of cheap headphone amps available now too, most are battery powered for portability.  e.g. FiiO E3 on Amazon for $7. Someone probably makes an AC powered quality unit for more money. Late night TV watching is a popular sport.  I am going for world champion. :thumb:

The problem with using little devices like this are twofold. First they are designed to work with a headphone level input. If the TV had a headphone out already we wouldn't need the box. Fixed line level outputs which what is on most TVs are a different impedance and voltage that what you would find on a headphone interface. the second problem is that the TV line outs are usually a fixed output (assuming that you are plugging it into a HT system that will take care of the volume control duties. To drive a pair of headphones from a fixed line level interface you need not only something that will do amplification and impedance matching, but it must provide volume control as well. The FiiO E5 ($23) have an electronic volume control, but I am not sure it can handle a line level source.
Title: Re: Headphones & TV's...???
Post by: richidoo on November 26, 2010, 03:05:28 PM
To use the volume control on the TV remote you need to use outputs from the TV. There should be RCA outputs on the back of it.  That line level output will work fine with an opamp based headphone amp which will have high input impedance. It would be nice to have a "gain adjust" on the amp like Tom suggests so the remote volume control will have good operating range. If you get wireless headphones there is probably a volume control on them or on their transmitter station.

http://www.ehow.com/how_4883556_use-wireless-headphones-tv.html