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Saturday, 5 December 2015

3. Big sound for your flat screen TV - in a stylish way!

Today’s TVs are flat and thin. They are easy to place in the room, do not take much space, and do not require any special stands or other special pieces of furniture we used to have in our houses or flats not so long time ago. You can even hang them on the wall, like a picture. The cathode-ray tube is dead, at least in the home TV set. There are flat screen TVs, and while the first ones were perhaps not as good as the CRT, today’s high definition technologies offer much better picture.

But what has happened to the sound?

Well, unless the room is really small, you have a problem. Why? Because most likely your TV will not be able to fill your room with the sound of acceptable quality. Instead, it is buzzing and tweeting, and you cannot get the nice, deep, reasonably loud and clear sound that your old big TV could produce seamlessly – especially if it was one from the era of wooden enclosures.

What on earth is going on? The technology has advanced so far, but they cannot make a TV that produces good sound from the in-built speakers? Well, they cannot. This is the price one pays for the thin plastic housing. There is no way to beat the laws of physics. Decent sound requires a decent enclosure of the speaker, of appropriate volume, and created from appropriate sturdy materials. That’s why a flat screen TV just cannot produce reasonably powerful, and pleasantly deep sound (your iPhone cannot do it either).
So what am I supposed to do? Go for the external amp and speakers? Or one of these unsightly “sound bars” the salesman wanted to add to my purchase?

Sophisticated surround systems for your TV have been on the market for over 20 years, and you can easily set up a home cinema with a great sound that will make your internal organs vibrate (and your neighbours mad, if you have them). But… you need a big amplifier and six or more speakers all around the room. And what if you do not want them? What if your room is furnished in a style with which all these additional appliances simply do not go, and you do not want them there; you do not need the home cinema sound in your nook of living room, you just want your TV set to sound ... good enough? 

Sound bars offer a little improvement, but only very little. Again, they are not large enough, and will not be able to reproduce the full range of sound correctly. Of course you can add a subwoofer, but in my opinion this is not a good solution either – a combination of tiny speakers and a subwoofer sounds just awful. And, going that route, you slowly start turning your room again into a repository of devices that you really do not want there. Especially if your room is nicely furnished with antiques, or you just prefer to keep it a bit traditional.

So what is the solution? Well, there is one. A very nice one.

Remember the big stereos from the 50s or 60s, solid pieces of furniture, often in quality wooden housings, carved and nicely finished?

 
     
They were made that way because they were bought with the intention to keep them for life. Or at least for a good portion of life. And now they are mostly dead, perhaps you have one at home, serving as a cabinet, or somewhere in the loft, or in the basement? And even if you do not have one, you can find plenty of them in antique shops or on Craigslist, and they are not too expensive. Time to bring one of them back to life!

I am quite serious. There is no reason not to. Typically, such an old stereo has all you need: solid enclosure, large speakers that most likely work, and even if not – they can be easily replaced. I would not necessarily rely on the amplifier part, as some  electronic parts not used for many years may have aged and therefor may not be working properly (although you may have a stereo that has been regularly used, in which case the amp may be quite good). This is not a problem, a small amplifier may be bought very cheap on eBay. And perhaps your TV has a built in amp that can be used for this purpose. If you like the idea, there are a few ways in which things can be put together, and so you can enjoy decent sound while watching the TV, without ruining the character of your place.

Here are a few ways in which things can be connected and configured. I am assuming that you are at least a little technically skilled and have some experience with audio devices; if not – ask someone who has to help, or enjoy learning how to do such things. For anything I may have not covered her, you will find tons of information on the web, just look for it.

  1.  If your stereo has speakers and amplifier all in good order, just connect the audio outputs of your TV to the stereo. Unless your stereo has a tube amplifier and you have no patience to wait until it warms up – in such case go for solution #2.
  2.  If the amplifier in your stereo is not good (you cannot get any sound from it), do not try to fix it. Open the back of your stereo (in most cases there will be a removable perforated panel), and find the wires going to the speakers (the wires will be running to the speaker either from one of the boards, or from the backside connections of the external speaker sockets. Cut them off, so you have enough wire to connect the speakers to an external amplifier (the wire can be easily extended, just keep the connections reasonably well insulated with a tape. There is no high voltage on these wires, but a short may damage the amplifier. Have a look at the impedance of the speaker (the number preceding the Ohm symbol, or the word ‘ohm’ on one of the speakers. Go on eBay and look for a small 15-20W stereo amplifier. Go for one that works on the mains power, and one that supports the impedance you found on your speakers (or a lower value – if your speakers are 8 ohm, and the amp supports 4 ohm, that is fine. The other way would be not). Once you have received the amplifier, connect the outputs of the TV to its inputs, and the speakers to the speaker outputs.  
  3. Now set your TV to external speakers, turn the volume to about 20%, and check if the volume changes with the use of the remote. If yes, everything is OK. If not, you may need to use a different output from your TV (e.g. the one for headphones, you may need a plug adaptor), or you may need to switch some settings in your TV menu. Once you can control the volume with your TV remote,  set the volume knob on the amplifier to maximum. You are good to go!
  4. If the speakers in your stereo are no good, you will need to replace them, ideally with identical ones. Just search on the Internet, it is incredible what one can find there. Alternatively, look for broad-range speakers with similar dimensions, impedance, and mounting holes (!); in most cases they will work OK – you are not building a Hi-Fi system. Remember to replace both channels at the same time, otherwise the system will not sound good.

Some final remarks:
  1. The amplifier usually is very small and can be placed inside the housing of the stereo, or behind the TV. Make sure that the area is well ventilated, and vacuum the inside well – these things collect a lot of dust!
  2. To be able to switch the amplifier or the stereo on and off together with your TV set using your remote, buy a power extension cable that can automatically switch additional devices once the “main” device is on. It is a simple and very reliable solution, the only disadvantage I have with my amp is that it produces a loud click in the speakers when switched off in this way. Well, I can live with that – a small price to pay for the privileges I receive in return. This is what the amp and the switchable extension cable look like (behind  the TV):
 
And here is my "TV stand" – both I and my wife love the way it both looks and sounds!

2 comments:

  1. my Bose amplifier and Sony receiver just stop working and fixed them is very expensive. Then I decided to use my old Onky receiver and i try it to connect my flat TV to this receiver and it doesn't work. How do you handle the analog connections?

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    1. Your TV should have analog outputs - line out, or audio out. You need a standard RCA audio cable, and just connect to any analog inputs of the onkyo receiver. It should work, of course you will not have surround sound (just stereo). Check various options on the TV, some TVs may allow to adjust the output level, and it may be turned down.

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