I'm not sure if this is the correct form for my question but it deals with a multi way speaker. I have an amp with 50 watt channels and I have a pair of two way speakers consisting of a full range driver and a tweeter. The full range driver requires 30 watts of power and the tweeter requires 20 watts of power. I added the values together for my amp to get 50 watts. Should I have not done this? Are both my speakers over powered or powered correctly? Thanks!
If the speaker has a properly designed crossover the power gets divided proportionally, as the full range falls off, the tweeter engages, so basically more or less constant power to the whole system. And for various reasons, the tweeter will only draw only a fraction of the power the full range does. So if the full range is drawing 30 watts, the tweeter will most likely draw something like 5 to 10 watts.
And in most cases one is better off having and amp capable of higher power rather than a lower power one. An amp being asked to supply more power than it can will cause clipping distortion, which if taken to extremes can blow out tweeters especially.
Mike
And in most cases one is better off having and amp capable of higher power rather than a lower power one. An amp being asked to supply more power than it can will cause clipping distortion, which if taken to extremes can blow out tweeters especially.
Mike
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Some good information Michael.
Keep an ear out for distortion. Whether the speaker distorts or the amp, it will sound different.
Replace requires, with 'can deal with up to'.
Keep an ear out for distortion. Whether the speaker distorts or the amp, it will sound different.
Even if the crossover weren't a factor, they work more simultaneously than separately.
I would tend to use a 30 watt amp with a 30 watt speaker and tweeter.
With 50 watts you can over drive your speaker.
This subject has been flogged to death on here and numerous otehr forums and always causes disagreements.
I ran a mobile disco for about 5 years with 200WRMS speakers and 200WRMS amp.
Never had any problems.
I worked in an audio shop for a while and the shop was full of dead speakers people had flogged to death.
If its not loud enough you need more powerful amp and speakers to match.
With 50 watts you can over drive your speaker.
This subject has been flogged to death on here and numerous otehr forums and always causes disagreements.
I ran a mobile disco for about 5 years with 200WRMS speakers and 200WRMS amp.
Never had any problems.
I worked in an audio shop for a while and the shop was full of dead speakers people had flogged to death.
If its not loud enough you need more powerful amp and speakers to match.
The consensus I have gotten is that 50 amps is to much power for my driver but shouldn’t be an issue as long as I don’t over power them/turn the volume up to the point of distortion. Is this a correct? Thanks!
If the amp is putting out 50 watts then it wont distort it will just blow up your speaker. Some speakers will go quite a bit past x-max. Its only when voice coil burns or fuses do you realise it was over driven.
It's not quite straightforward to figure out. Speakers fail from mechanical means ( bottoming, torn spider, damaged leads ) and also simply overpowering. ( exceeding a certain voltage, or too much thermal buildup )
If the speaker was competently designed and manufactured, it will have a crossover network that supplies high frequencies only to the tweeter, and features a low pass for the midrange or full range, and possibly a 'pad' to lower the voltage sensitivity of the most sensitive device to the lowest, matching sensitivity.
Depending on the efficiency and the total bandwidth of the tweeter, it may be fine rated at 5 watts of power in a 3 way speaker with a total power handling capacity of 100 watts, if for example it is a horn loaded high efficiency unit.
Simply adding the 'capacity' of individual drive units in a multi-way unit doesn't work. Manufacturers use a method to specify the maximum amount of power with noise, which will not result in a failure. Some give this as a voltage into the system minimum impedance. ( in the case of many pro-audio finished systems )
I hope that partially answers your question.
Sorry I'm not sire if I was clear. I have built a pair of bookshelf speakers. Each has a full range and tweeter with the power requirements I stated above. I have no cross over right now and have played the speakers with both the tweeter and full range connected together to the amp. I am planning on building a crossover soon. Do I have the risk of blowing my drivers right now before the crossover. Do I have a change of blowing the drivers after I install a crossover? Thanks!
I would simply say yes to this but sometimes it isn't that simple. Some speakers would push their cones far enough to distort before they reach 30W, and some after reaching 30W depending on the way they are set up.
What the situation calls for is for you to keep a watch on it and use them sensibly 😉
The amplifier is at risk of damage if the combined impedance is too low. The tweeter is at risk of mechanical damage, since it's asked to reproduce frequencies that will cause excessive motion.
Stop while you are ahead. A passive crossover is not trivial to design or execute. Internet 'calculators' are less than worthless.
As we discussed in the other thread... it's not that simple.
First when speakers are wired in parallel, you are asking them both to take the amplifier's full power. So no they don't add, you simply end up killing the weakest.
Lots of people commonly run 100 watt speakers on 250 and 500 watt amps without trouble. The power rating is not a hard ceiling... 31 watts and poof... what it is is a measure of how much power the driver can absorb for an acceptable cone movement and voice coil temperature. A proper driver can generally sustain short bursts well beyond the stated limits.
The reason this is true is that music (other than hyper-compressed crap) has a fair bit of dynamic range. Dynamic Range is the ratio between the loudest and the quietest parts of a song (movie, speech, video, etc) While the 250 watt amp may hit peaks of about 200+ watts for a few milliseconds at a time the average power is far lower. On properly recorded music it can be as low as 5 or 10 watts.
Now the risk in overpowering like that is 1) Celine Dion hits one of her 15 second high notes, 2) The music is basically someone fingering the end of a guitar cord, 3) The record starts skipping in the loudest part of the anvil chorus.
It is probably accurate to say that most "living room" stereo happens at an average of 4 or 5 watts.
Does that help?