Solved! So, how many watts are my speakers?

[Gal Blech]

Hi, I got some old speakers that sounds really good and I need to buy an Amp.
The problem is that I don't know how many watts the speakers are.
We're talking about 2 speakers, each with:

1. woofer: Philips AD8061/W8
2. tweeter: Philips AD0161/T8
3. mid-range: MEROT 5030S, 8 ohms, 20 W

For the first two I found an old Philips catalog (http://www.verheijde.net/library/Philips_1978-10_CM3b_Loudspeakers_939810550011.pdf).
In the catalog it is very clear that the tweeter and the woofer are 8 ohms, but I couldn't understand how many watts.
For the mid-range I couldn't find a thing, but it's written on it 8 ohm, 20 W.

So, how many watts are my speakers?
Is there a specific number or is it a range?
And how much watt amp do I need to buy?

Thank you,
Gal.

 

[Sonic Illusions]

The woofer is rated at 30 watts, so we can safely say 30 watts continuous for the whole system, IF the original crossover parts, as designed, are present. Even though the mid is rated at 20W, keep this in mind: The woofer demands the most from your amp, because most of the energy required, goes to reproduce the bass octaves of the sounds we hear. The mid has the frequencies covered by the woofer filtered out, so it "sees" less power (wattage). I didn't look up the spec's of the tweeter, because it's irrelevant. If we did find the spec's, I wouldn't be surprised to see a power rating of 10-15W for the tweeter. To be safe, don't choose an amp rated over 30WPC, continuous RMS power. 25WPC would be safer. The reason is this: amp clipping (occurs when volume is too high causing distortion) is usually audible, but sometimes you may not notice it. Amp clipping, even with a low-powered amp, can destroy tweeters. Some systems include tweeter protection, but most do not.

 

[Gal Blech]

The woofer is rated at 30 watts, so we can safely say 30 watts continuous for the whole system, IF the original crossover parts, as designed, are present. Even though the mid is rated at 20W, keep this in mind: The woofer demands the most from your amp, because most of the energy required, goes to reproduce the bass octaves of the sounds we hear. The mid has the frequencies covered by the woofer filtered out, so it "sees" less power (wattage). I didn't look up the spec's of the tweeter, because it's irrelevant. If we did find the spec's, I wouldn't be surprised to see a power rating of 10-15W for the tweeter. To be safe, don't choose an amp rated over 30WPC, continuous RMS power. 25WPC would be safer. The reason is this: amp clipping (occurs when volume is too high causing distortion) is usually audible, but sometimes you may not notice it. Amp clipping, even with a low-powered amp, can destroy tweeters. Some systems include tweeter protection, but most do not.

Really?
I thought it's 30W woofer, 20W mid and ~10W tweeter ---> 30+20+10 = 60W.
There is in there the tweeter specs (page 228) but I don't know what are the differences between "power handling capacity" and "operating power".
And what about that range of watts people are talking about?

thank's for the fast reply 🤗

 

[americanaudiophile]

There isn't a strict definition of those terms but I would say that capacity is the absolute max the driver can handle and operating is the practical maximum you should use.
I would probably go with a 50-75 watt amp. Having a bit of extra power gives you a cushion against the amp clipping which would damage the tweeter.
It will also depend on the quality and current capability of the amp. The small digital amps and boards you see online are usually rated much higher than their actual power rating. You have to dig into the specs to see the actual rating. Not unusual for a 100 w x2 amp to actually product 30 w x 2.
How loud the system will play will depend on the crossover and how the cabinet is designed.

 

[Sonic Illusions]

In my experience with speakers (40 yrs) those power ratings stamped on the magnets are almost always continuous. I too, prefer headroom, but driving those speakers with a 50-75 WPC amp will surely destroy the woofer. Do you want to learn the hard way, by being tempted to crank them up, only to smoke the woofer coils? It's a trade-off; do you fry the woofer or tweeter. With such a low power rating on the speakers, you won't be breaking any SPL records, but the volume levels with those speakers being driven by a decent 25-30 watt amp can surely be satisfying. Amp spec's can be very misleading, so pay attention to the 'continuous' rating at 8 oms. Regarding your comment about adding the power ratings of the individual drivers together for total system power, it doesn't work that way. You would be doubling the power the woofer can handle - not good. Think about it this way: each driver is designed to reproduce certain frequency ranges, dictated by their design and the crossover filters. Higher frequencies require less power. So your woofers take the most power for the bass, the mids take a bit less and the tweets take very little power, compared to the woofers. Your speaker system's power rating will not exceed that of the woofer. There are some exceptions, but it's safe to say your speakers handle the power of which the woofer is rated.

 

[Gal Blech]

Ok, thank you very much, I was struggling with that for some time!