[Zidane82]

Hey.

I have a HiFi . LG FA 166DAB and the system has a total output of 160W and it came with two 80W speakers that I find too boomy with no where near enough treble .

Anyways luckily I have a TWO pairs of spare speakers that sound much better and they are only 40W speakers (each) so I'm wondering if I can fix up BOTH sets off speakers and get a great sound from ALL four speakers ( 4 x40W is still only 160W) or am I mistaken ?

They will only be played at average volume certainly not blasting out at top volume or anything close.

Thanks !

[Nigel Goodwin]

Quote:

Originally Posted by Zidane82

Hey.

I have a HiFi . LG FA 166DAB and the system has a total output of 160W and it came with two 80W speakers that I find too boomy with no where near enough treble .

Anyways luckily I have a TWO pairs of spare speakers that sound much better and they are only 40W speakers (each) so I'm wondering if I can fix up BOTH sets off speakers and get a great sound from ALL four speakers ( 4 x40W is still only 160W) or am I mistaken ?

What impedances are both speakers? - you also need to be aware that many specifications on cheaper audio (like LG) are often wildly imaginary - the only figures worth noting are RMS continuous.

[chrisjr]

Make life simple for yourself. Connect just one pair of speakers to the unit.

Forget about the 160W rating of the thing, it is (like many such units of this type) bragging about it's size but fails to live up to the boast. The specs in the manual say it has 160W output but only a 45W power consumption from the mains. So where do the remaining 115W come from?

Which probably means it is actually 2x20W RMS and the 80W per channel is some meaningless made up measurement unit. Which means you are very unlikely to blow your 40W speakers, unless they too are measured using some random fictional measurement system (only RMS figures really mean anything).

Also 4x 40W speakers do not necessarily add up to 160 W, Doesn't really work like that.

[Zidane82]

I'll try and find a bit more out about the specs - if there was going to be an issue .... anyone know for sure which part would suffer ..... the amplifier or the speakers ??

[Nigel Goodwin]

Quote:

Originally Posted by Zidane82

I'll try and find a bit more out about the specs - if there was going to be an issue .... anyone know for sure which part would suffer ..... the amplifier or the speakers ??

If you put them in parallel the amplifier will be most at risk (depending on the relevant specs of everything).

[gemma-the-husky]

Many amps accept 2 pairs of speakers

A, B, A+B. Does yours?

[Zidane82]

Quote:

Originally Posted by gemma-the-husky

Many amps accept 2 pairs of speakers

A, B, A+B. Does yours?

Na just the normal four clamps -two wires each speaker.

[Zidane82]

Could I get away with using the four speakers if as I said I only use the unit at low volume say a third of max volume ?

[Nigel Goodwin]

Quote:

Originally Posted by Zidane82

Could I get away with using the four speakers if as I said I only use the unit at low volume say a third of max volume ?

'Probably', but there's always a chance of killing the amp.

Putting them in series would be safer, with no chance of damaging anything.

[chrisjr]

As I posted above. Save yourself all the hassle and use just one pair of speakers. If the speakers are rated at a genuine 40W RMS there is no chance of the amplifier blowing them through raw power alone. The 160W spec is a fabrication, it cannot possibly produce 80W per channel while only consuming 45W from the mains. That breaks a fundamental law of physics so cannot possibly happen.

If the speakers are 8 ohm impedance then they could be wired in parallel as the amplifier appears to be rated into 4 ohms. If they are less than 8 ohms then do not connect in parallel. Oh and two 40W speakers in parallel does not equal one 80W speaker so even if the amp could dump 80W into the speakers you could still blow them both.

If you must use two speakers on each amp output (and I say again it is not necessary) then wire them in series, ie

Amplifier +ve terminal --> Speaker 1 +ve terminal
Speaker 1 -ve terminal --> Speaker 2 +ve terminal
Speaker 2 -ve terminal --> Amplifier -ve terminal

That would be safer for both amplifier and speakers.

But at the risk of sounding like a broken record there is little point trying to wire up both pairs of speakers. Save yourself a world of hassle and just use one pair. You are not going to damage anything, unless the speakers are less than 4ohms impedance.

[Zidane82]

Quote:

Originally Posted by Nigel Goodwin

'Probably', but there's always a chance of killing the amp.

Putting them in series would be safer, with no chance of damaging anything.

Quote:

Originally Posted by chrisjr

As I posted above. Save yourself all the hassle and use just one pair of speakers. If the speakers are rated at a genuine 40W RMS there is no chance of the amplifier blowing them through raw power alone. The 160W spec is a fabrication, it cannot possibly produce 80W per channel while only consuming 45W from the mains. That breaks a fundamental law of physics so cannot possibly happen.

If the speakers are 8 ohm impedance then they could be wired in parallel as the amplifier appears to be rated into 4 ohms. If they are less than 8 ohms then do not connect in parallel. Oh and two 40W speakers in parallel does not equal one 80W speaker so even if the amp could dump 80W into the speakers you could still blow them both.

If you must use two speakers on each amp output (and I say again it is not necessary) then wire them in series, ie

Amplifier +ve terminal --> Speaker 1 +ve terminal
Speaker 1 -ve terminal --> Speaker 2 +ve terminal
Speaker 2 -ve terminal --> Amplifier -ve terminal

That would be safer for both amplifier and speakers.

But at the risk of sounding like a broken record there is little point trying to wire up both pairs of speakers. Save yourself a world of hassle and just use one pair. You are not going to damage anything, unless the speakers are less than 4ohms impedance.

Thanks guys . I was hoping to get a kinda 360 surround sound by using the 4 speakers . I presumed that two sets have to sound better than just the one being that each set are only half as powerful as the set that came wth the system originally .
Both sets of speakers are 6ohms incidentally so I'm real tempted to set them up in series as mentioned above ..

[Zidane82]

Now thinking outside the box . How about Plan B ?
Could I revert to using the original BOOMY heavy bass 80W speakers AND put one of these better sounding 40W sets but wired up in series ???

That sounds like a posssible compromise ?

[chrisjr]

Quote:

Originally Posted by Zidane82

Thanks guys . I was hoping to get a kinda 360 surround sound by using the 4 speakers.

You won't. All it will do is move the stereo image closer to the middle of the four speakers.

Quote:

Originally Posted by Zidane82

I presumed that two sets have to sound better than just the one being that each set are only half as powerful as the set that came wth the system originally .

Not necessarily. Power rating has absolutely sod all to do with sound quality. As does the number of speakers you use. And as I keep mentioning the 80W per channel rating is a work of fiction anyway. In fact it is even possible your 40W speakers will go louder than the original speakers. The power rating is only one factor in how much noise they make.

Quote:

Originally Posted by Zidane82

Both sets of speakers are 6ohms incidentally so I'm real tempted to set them up in series as mentioned above ..

Well wiring in parallel would make the total load 3 ohms which the amplifier might not like. So series would be safer.

[chrisjr]

Quote:

Originally Posted by Zidane82

Now thinking outside the box . How about Plan B ?
Could I revert to using the original BOOMY heavy bass 80W speakers AND put one of these better sounding 40W sets but wired up in series ???

That sounds like a posssible compromise ?

It might sound absolutely horrible. To use multiple speakers properly requires matching them carefully otherwise the results can end up sounding worse than any single speaker in isolation.

Not something to be recommended unless you really don't care about sound quality.

[Zidane82]

Ok thanks .

I'll give it all a bit more consideration. I just presumed putting a set of speakers with particularly good bass sound but poor treble alongside a set of speakers with a good treble sound and poor bass would be a decent combination

[gemma-the-husky]

If you use the 40w speakers only, and like the sound it will probably work better. What the amp has to do is deliver peak power occasionally, without clipping, which a powerful amp will be able to do.

Since you need 10 times the power to go twice as loud, it will still be pretty good. I doubt you rarely turn the volume to full power snyway?

I think that is right, isn't it, experts?

[grahamlthompson]

Quote:

Originally Posted by gemma-the-husky

If you use the 40w speakers only, and like the sound it will probably work better. What the amp has to do is deliver peak power occasionally, without clipping, which a powerful amp will be able to do.

Since you need 10 times the power to go twice as loud, it will still be pretty good. I doubt you rarely turn the volume to full power snyway?

I think that is right, isn't it, experts?

The efficiency of the speakers is a major point. Small speakers though capable of high quality audio need a lot of power. Large speakers are much more efficient. You can get a lot of sound from a high quality 15/20W amplifier coupled with large high efficiency speakers as HiFi enthusiasts from the early days of limited power valve amplifiers will testify

But yes you are correct.

[Zidane82]

Soooooooo. In theory . If I were to try two sets of speakers IN SERIES .

Which combo is most likely to give the best sound ?

A : The 80W Heavy Bass ones with a set of 40W High Treble ones ( not too much bass)

OR

B : The two sets of 40W speakers again set up in series .


To my amateur mind the first option seems more tempting , as in theory , I'd be getting the Bass from the 80W ones placed in the corner of the room next to the HiFi Amp and decent Treble ( and less Bass ) from the 40W speakers placed in front of us .

[grahamlthompson]

Quote:

Originally Posted by Zidane82

Soooooooo. In theory . If I were to try two sets of speakers IN SERIES .

Which combo is most likely to give the best sound ?

A : The 80W Heavy Bass ones with a set of 40W High Treble ones ( not too much bass)

OR

B : The two sets of 40W speakers again set up in series .


To my amateur mind the first option seems more tempting , as in theory , I'd be getting the Bass from the 80W ones placed in the corner of the room next to the HiFi Amp and decent Treble ( and less Bass ) from the 40W speakers placed in front of us .

What you need is a crossover. These split out the bass, midrange and treble frequencies and send them to the appropriate drive unit. The Bass heavy speaker should have one in each one. You could use it to connect the speakers with a better midrange and treble instead of the built in ones. That way you will not have any impedance issues. Personally I would look for a pair of decent speakers to cover the full frequency range. Or you could simply disconnect the smaller drive units in the larger bass units effectively creating a subwoofer.

Type this into Google

how to build a crossover for speakers

[Chris Frost]

Zidane82, sorry to be direct, but you're trying to make a silk purse out of a sows ear. It's not going to be possible to distribute the power evenly between the speakers without some kind of intervening bit of circuitry. Forget about the wattages for a moment and just look at the impedance (resistance) of the speakers. When the speaker impedances are different then the power split will reflect that. IOW, one set of speakers will be louder than another.

If you really want to pursue this then have a look at "impedance matching volume controls". These devices use transformers to balance the power distribution between speakers of differing impedances.

The rub with any passive device like this is that it takes a chunk of the power that's driving the speakers and diverts it to run the circuit. The effect is that the power available to the speakers gets smaller. The LG doesn't have that much oomph in the first place. The wattage figure for it is derived from a high distortion figure and driving at 1kHz rather than with a full spectrum music signal. What's measured isn't a real world figure but an engineering exercise.

In all honesty, if you want 4 speakers connected then just go with chrisjr's suggestion and forget about adding in the LG speakers for more bass.

[chrisjr]

Quote:

Originally Posted by Zidane82

Soooooooo. In theory . If I were to try two sets of speakers IN SERIES .

Which combo is most likely to give the best sound ?

A : The 80W Heavy Bass ones with a set of 40W High Treble ones ( not too much bass)

OR

B : The two sets of 40W speakers again set up in series .


To my amateur mind the first option seems more tempting , as in theory , I'd be getting the Bass from the 80W ones placed in the corner of the room next to the HiFi Amp and decent Treble ( and less Bass ) from the 40W speakers placed in front of us .

As others have posted your option A is full of potential problems.

There is no guarantee that you will get anything remotely resembling a decent sound out of that combination. The problem is that without any frequency filtering to separate the two speakers both will be producing sound at the same frequencies over much of their range.

The sound waves from the two speakers can combine in all sorts of unpredictable ways. They can partially cancel out each other or reinforce each other and any combination between those extremes. Probably going to end up sounding a complete mess.

The only way to combine two different speakers properly is to use some sort of crossover filter that feeds different frequency ranges to each speaker and also balances out the relative loudness of the two so that you get a smooth spread of sound across the frequency range.

And if you do try to combine two different speakers they have to be sat one on top of the other really. If you separate them physically you introduce all sorts of additional sound delays and level shifts that can also affect the resulting sound.

You also mention having the speakers in the corners. This could be the cause of the emphasised bass. Speakers should be kept out of corners and away from walls, unless specifically designed for such locations. The bass from a speaker is much less directional than the higher frequencies so it is affected more by reflections off the walls, corners make the reflections worse. This can in certain circumstances reinforce the bass sound.

Speakers should be placed in free space with the tweeters (high frequency drive units) at about ear height and equally spaced either side of the listening position.

[2Bdecided]

Quote:

Originally Posted by Zidane82

Soooooooo. In theory . If I were to try two sets of speakers IN SERIES .

Which combo is most likely to give the best sound ?

A : The 80W Heavy Bass ones with a set of 40W High Treble ones ( not too much bass)

OR

B : The two sets of 40W speakers again set up in series .


To my amateur mind the first option seems more tempting , as in theory , I'd be getting the Bass from the 80W ones placed in the corner of the room next to the HiFi Amp and decent Treble ( and less Bass ) from the 40W speakers placed in front of us .

You could have tried it by now and then you would know

[mark6226]

The power rating is meaningless, especially on low end or Japanese kit. I have hi end bi-amped cyrus system. It is rated as 55 watts per channel. I have a massive sitting room and my amps absolutely fill my room with sound at around 25% power.
Ignore figures like 160 watts per channel on low end gear. It is simply not achievable. And to play any system at that level of volume would probably blow your windows out and deafen you.
if possible, always try before you buy and then judge for yourself. But don't get seduced by the power numbers game. Generally is all a lie designed to seduce you. But it is an easy trap to fall into.

[jjne]

Quote:

Originally Posted by mark6226

The power rating is meaningless, especially on low end or Japanese kit.

Explain?

Some of the best consumer audio kit is/was manufactured by Japanese companies.

[grahamlthompson]

Quote:

Originally Posted by jjne

Explain?

Some of the best consumer audio kit is/was manufactured by Japanese companies.

I have just replaced a elderly £1400 pound Denon AVR receiver with a Sony Unit costing approx. 1/3 the price. Paired with my KEF speakers if anything it has superior sound. More importantly it has more HDMI inputs and outputs and support for more recent and more advanced audio systems like Dolby DTS Master HD.

For many years Japanese audio kit has been excellent. Technics Panasonic and Sony being an example.

Mark6226 may have only 55W per channel, I bet he has largish efficient loudspeakers with adequate bass response. These are massively more efficient than the small speakers many of us have to use.

That's the reason why high end AV kit from anywhere have power outputs of over 100W per channel into 6 or more channels and require a separately powered subwoofer to create a stunning sound stage from a suitable source.