Sound Question: Amplifier And Speakers Risks

[CoMiKe]

Hi all! Hope you can help me with some sound questions.

Sometime ago (1998 or so), my brother bought a Technics sound system with an SA-EH60 amplifier.
Unfortunately, the amplifier has burnt, and now we have 5 beautiful speakers hanging on my room doing absolutely nothing. And I can't live with that on my conscience.

So I decided to buy a new amplifier, that should be able to feed all 5 speakers without taking to much risks.

The problem is the speakers are very different between them, so we get to the feared problem of impedances. These are the speakers we have:

Central speaker - Model SB-PC60
Input: 100W (Music), 50W (DIN)
Impedance: 8 ohm

Front speakers - Model SB-EH60
Input: 160W (Music), 80W (DIN)
Impedance: 6 ohm

Surround speakers - Model SB-PS60
Input: 50W (Music), 25W (DIN)
Impedance: 4 ohm

Well, I couldn't get more different impedances

First question: ¿What's the difference between 100W (Music) and 50W (DIN)?
I suppose the actual power of my speakers are 50W (central), 80W (front) y 25W (surround), and so these are the values I'm taking as reference at the time of searching for a new amplifier.

Second question: After so much searching, I'm weighting up the adquisition of one of the following amplifiers:

Skytronic 103.153
Power supply: 230Vac, 50Hz
Impedance: 8 ohms
Output power (PMPO): 2 x 140W + 3 x 40W

McVoice HVR-80
Power supply: 230Vac, 50Hz
Impedance: 8 ohms
Output power (PMPO): 2 x 80W + 3 x 30W

As you can see, both amplifier specifications say they support 8 ohm speakers, but on the back of both amplifier they state different impedance values (!!).

As far as I know, the impedance of an amplifier should be the minimum of your speakers, as the lower is the impedance of the speakers, the higher will have to be the voltage applied by the amplifier to the speakers to generate the same power. ¿Am I Right?

With the speakers I have, ¿what's taking more risk, the speakers or the amplifier?

It seems if I raise the amplifier volume a lot, I'm going to trash it, as it's going to have to generate higher voltages to feed the front (80W, 6 ohm) and surround (25W, 4 ohm) speakers, and the amplifier could get warmer than hell, huh? <_<

Can you please advise me about this topic?

Thanks in advance.

 

[BaDToaD]

First question: ¿What's the difference between 100W (Music) and 50W (DIN)?
I suppose the actual power of my speakers are 50W (central), 80W (front) y 25W (surround), and so these are the values I'm taking as reference at the time of searching for a new amplifier.

Second question: After so much searching, I'm weighting up the adquisition of one of the following amplifiers:

Skytronic 103.153
Power supply: 230Vac, 50Hz
Impedance: 8 ohms
Output power (PMPO): 2 x 140W + 3 x 40W


McVoice HVR-80
Power supply: 230Vac, 50Hz
Impedance: 8 ohms
Output power (PMPO): 2 x 80W + 3 x 30W

Can you please advise me about this topic?

Thanks in advance.



The ohm question I'm not sure about except the Skytronic backplate seems to suggest it can support any value between 4 and 16 ohms.

The power stuff I can probably help with.

Din is the actual power the amp can deliver for an extended time.

Music Power is usually 2in and PMPO (Peak Music Power Output) is 4in so taking that into account your amps above are not as powerful as they look. However they may be loud enough since to double volume you need to square the output power. i.e. a speaker with 100 Watts running through it will only be twice as loud as a speaker with 10 Watts running through it.

ALSO contrary to popular belief most speakers are damaged by underpowered amps that distort and clip damaging the speakers. To that end if you get either of the amps above be careful when you crank the volume.

 

[CoMiKe]

Thanks for the information, BaDToaD!

I've finally acquired an Onkyo TX-DS595 AV receiver on eBay.

It delivers 110W @ 6 ohm on all the 5 channels, so it should be powerful enough to feed my speakers.

Thanks again for your answer.