amplifying external speaker for tv??

[friendshipcafe]

hi. i wanted to be able to hear the tv while getting ready in the bathroom in the am so my husband put in a wall speaker in the bathroom and ran speaker wire to the tv. it is just not loud enough so we tried 2 different amplifiers and the 40 watt one was still not very loud and the 100 watt one just kept clicking in and out and in and out so not sure if defective or we are doing something wrong. any suggestions on the best way to make this work before we buy any more things. just want louder sound in the bathroom area. the tv is not blue tooth enabled. any suggestions greatly appreciated.

[jagabo]

Speaker wire to the TV? TVs don't normally have speaker level outputs. What is the wire plugged into? A headphone output (typically 3.5mm stereo pin plug)? Line level output (typically RCA connectors)? A 40 watt RMS amp should have been enough to blow you out of the bathroom.

[betwixt]

I would add that you should be extremely careful if you run any electrical connections to a bathroom, especially from a TV. In many countries that would be illegal due to the risk of the wires carrying high voltages.

Brian.

[pandy]

I recommend to search for wireless speakers - Bluetooth range is less than 10m (around 5 - 8 real life scenario) but other technologies offer even 100m range (like FM over 2.4/5.8GHz)

[friendshipcafe]

right now it is the headphone jack from the tv to the rca inputs of a 100 watt amp. speaker wires go from the amp to the 150 watt speaker in the bathroom wall. the sound is not very loud from speaker in bathroom. it also with this amp keeps clicking in and out and sound goes in and out. the 100 watt is louder than the 40 watt tried first. wondered if the amp was bad?? or are we doing it wrong?

we had bought the speaker first and had the problem and before we gave up on the speaker ( that they cut a whole in the wall to put in ) wanted to see if able to fix problem. probably should have tried wireless speakers but was not sure how to get to work with tv so went this route first.

[jagabo]

Do you have some other speakers you can test the amp(s) with? So you had reason to believe the in-wall speaker was bad to begin with?

[pandy]

right now it is the headphone jack from the tv to the rca inputs of a 100 watt amp. speaker wires go from the amp to the 150 watt speaker in the bathroom wall. the sound is not very loud from speaker in bathroom. it also with this amp keeps clicking in and out and sound goes in and out. the 100 watt is louder than the 40 watt tried first. wondered if the amp was bad?? or are we doing it wrong?

we had bought the speaker first and had the problem and before we gave up on the speaker ( that they cut a whole in the wall to put in ) wanted to see if able to fix problem. probably should have tried wireless speakers but was not sure how to get to work with tv so went this route first.

Thus no sense for you to buy wireless speakers (i.e. wireless link, amplifier speaker) as you have already everything except wireless link - there is plenty cheap devices that provide audio link without cable.
Level difference can be related to few thing:
low speaker efficiency - more efficient speaker is the lower power required to create sonic pressure - difference 6dB will give perceived twice louder (silent) sound - with typical speakers efficiency can be like 86dB (poor efficiency speaker) or 92 - 93dB efficient speaker (good efficiency) - this can create situation where 100W electrical power can be less efficiently turned to sound than different speaker with for example 50W amplifier.
And speaker efficiency is only one of factors that decide how loudly perceived is sound, amplifier can be fake 150W so called PMPO or some peak power (for example typical peak power is 10 - 100 times big of average) where different amplifier provide real - average power like 40W, speaker enclosure is important - it can reduce speaker efficiency (or increase).
Also it can be difference in levels (one amplifier provide 40W with 1V input level second provide 150W but with 5V input level thus feeding 1V to 40W amp give us 40W but feeding same level to 150W will give us 30W only).
There is many possibilities and without detailed information's or perhaps even checking (for corrupted or miswired cabling for example) it is very difficult to provide answer what is wrong.

[hello_hello]

The "clicking in and out" thing sounds like the amp trying to protect itself from what it sees as something too close to a short circuit on the speaker outputs. It sounds like a "relay" switching in and out, disconnecting the amp's outputs. Assuming there isn't a short curcuit (the speaker wires don't have a short), it could be caused by using the wrong speakers. The amp probably has a rating for minimum impedance (or an impedance range) and it's often written near the speaker outputs. It might be something like 8 ohms. If it is and the speakers are 4 ohms, that might cause it (the speakers should have some sort of impedance rating in ohms, often printed on the back of the speaker box or on the speaker magnet if they're not in an enclosure). Or the amp could be faulty. Or one of the speakers could be faulty or it's been driven too hard and the amp sees it as a short circuit.

I'd try connecting something like an MP3 player to the amp to see what happens. If it still clicks in and out then it's a problem with the amp and/or speakers which needs to be fixed. If it works you can probably increase/decrease the volume of the MP3 player itself to see if the amp will produce an acceptable volume. Then you can connect the TV again and see how well it works.

Because you're connecting a headphone output to a line level input, you might find you need to turn up the volume on TV/MP3 player quite a bit for it to supply enough level to the amp. Probably more than you would if you were using headphones. If the amp isn't getting enough signal on the input it'll never be loud no matter how many watts it is.