Sony SAW Speakers & Amp

What a load of faff!

I know about Ohms law and dont have to refer to a calculator on line.

Your case description is so extreme only a fool would try that. But there's always one I guess... :rolleyes:

Clipping is one type of distortion that an overdriven amp will produce. If you study basic electronics and technology you'll realise that an over driven amp will also produce many more harmonics and phase distortion to name a few. Look these up and see what these can do to high powered speakers! And also study how an amp does it's work. Square waves anyone?? I don't think so.

I mean calling my explanation 'bollocks' is what i'd expect especially after your ridiculous practical explanation you gave.

Some of the 'stuff' you have said is fine. But you contradict your opening comment by most of your post.

Anyways go with who you wish. I will go on the advice and practical evidence recieved from teachers and producers alike.
OK.

first, I have studied electronics, firstly at GCSE Level, secondly at A level and thirdly at degree level,
I've been making speakers, and amplifiers as a hobby for the past 11 years,




Anyway, you may be aware of ohms law, but you seem to ignore that it applies?

you say get am amp that's bigger than the speakers. and there will be no trouble?

I'll admit that my example is extreme (100W amp 3W speakers), but it was meant to be extreme to show what you'd said was such bollocks,
or are you now revising your statement...

as far as I read it was that the rule is that your amp has to be higher powered than your speakers are rated at else you're likely to overdrive the amp and make the amplifier clip and distort and that'd damage much higher power speakers, (though surely if that were the case it's damage lower powered speakers as well exactly the same)?

you can never go wrong yet I pointed out that you can go wrong. with this... (yet a brief example involving just the smallest about of actual scientific theory prooves what you said wrong)

going back to the calculator, take a less extreme example, use 75W spakers with a 100W amp.

when your amp is cranked up full there is 3.5 amps running through the voice coil, yet the speaker can only handle 3 amps, as it's rated at 75W, and it can't handle that continuously either, that's a 14% overload over what the speaker can handle.
the voice coil will deteriorate over time.

As for the rest of my post.
Yes, I pointed out that if you have 75W speakers you can use a 100W amp and not break the speaker assuming that you don't turn it up all the way...

in which case, what's the point in spending extra on a larger amp?

i.e your example can work, but only if you waste a lot of the capacity of your amp.

and yes, clipping, like a square wave. try looking at the output of a amplifier that's clipping with an oscilloscope,

in fact this image descripes better than I ever could with words

clip.gif


now here comes the scientific fact part again, listen carefully I know you had trouble with that the first time.

look at the wave form, you see in the first example the part where the waveform reaches around a quarter of the way to the top is about a quarter of the way into the graph...
yet the second waveform shows that the the wave reaches half way to the supply voltage (where it clips) in about an 1/8 of the time taken to complete a half cycle.

The point is, (and this is where it gets really obvious), that higher voltage is on for longer, the current flows at a higher value for longer, more power is coming out for a longer time. and thus since there is power on for a greater period of the cycle of the wave the speaker coil is generating heat for a longer period, which is harder to disipate, and the energy builds up until it's rather hot and the speaker coil can melt.

you talk about harmonics introduced, but do you have any idea how you can make a square type wave? square type waves contain almost infinite higher frequency sine waves, so what you're saying (in your second post where you tried to get technical) and what I'm saying (in my first and second post) is essentially the same thing, clipping produces a square type looking wave, you'll see it in the diagram above. and that waveform contains a large amount of harmonics that actually go into making a square type wave form.

however, you're still wrong.

Sure, clipping is
producing extra harmonics but they never approach the levels of the amplified high frequency source signals.

source: http://www.adx.co.nz/techinfo/audio/note128.pdf

what's that? oh just some guys research paper that shows what you think that you've been taught, is (as I said) bollocks.




So lets sum up.
you get an amp that's too small, you over drive it you'll break even high powered speakers,
so the best thing that you can think to do is get an even higher powered amp, even though you surely must realise that you can't turn it all the way up without damaging the speakers that you have.




having said that, I'm giving up now.

you made a statement said that it was a rule, when proved that your 'rule' was not a rule and was just blatantly wrong you sit there moaning about how you can't be wrong and you'd rather believe advice of producers, what producers? what teachers, can you even link to anything to show what you said is a fact?

or do we just take your word for it, against the odds of common sense, basic examples, and now scientific research papers...
 
so the best thing that you can think to do is get an even higher powered amp, even though you surely must realise that you can't turn it all the way up without damaging the speakers that you have.
There are different types of speaker ratings, so you need to clarify what mean. Some speakers offer specifications on continuous pink noise, continuous program noise, and peak handling. I'll give you an example.

175 W Continuous
Program Power

87 W Continuous
Pink Noise
JBL Pro suggests using twice the rated RMS of every speaker they offer, which they call continous program power. This supposedly gives you 3dB of headroom to work with. If you do turn it up all the way, the speaker is more likely to hurt you, before you hurt the speaker. Some manufactuers even suggest using four times the rated RMS of the speaker.

The point is, you're more likely to damage a speaker by underpowering (and I use that term loosely) than overpowering. You can damage the speaker either way, but it's always safer to have headroom. I think that's the point Remeniz was trying to make, even though he was a bit vague.
 
All I was trying to say is that I like to get slightly higher rated amps than the speaker rating so I can achieve the loudness I want without distortion. I don't see the point in running an amp till it distorts just so you get a loud sound. It doesn't sound good. And I have blown a few speakers, mainly the tweeter in multi set ups, through doing the latter.

Root you are correct and I understand what your saying and your graphical explinations. (takes me back to college). I bow down from this discussion and I apologise for 'my' arrogance.
 
I've got a mate who has a Denon 2500W Amplifier that he insists he doesn't want anymore, so he says he wants me to have it. As long as I'm sensible with the volume, it will be fine with my speakers won't it? Also how will I know whether its the speakers or the actual sound thats distorting (I will be playing mp3s from the PC which are lossy)?

EDIT: The amp is here, these speakers are incredible! Thanks everyone for the help.
 
I've got a mate who has a Denon 2500W Amplifier that he insists he doesn't want anymore, so he says he wants me to have it. As long as I'm sensible with the volume, it will be fine with my speakers won't it? Also how will I know whether its the speakers or the actual sound thats distorting (I will be playing mp3s from the PC which are lossy)?

EDIT: The amp is here, these speakers are incredible! Thanks everyone for the help.


Get some pics on here... :D
 
2500W? With all due respect, I doubt it :p. Allthough I could be wrong! Are you sure he didnt accidently read an extra zero? :)
 
SDC11215.jpg


SDC11216.jpg


I was told it was a 2500W amp, it may be incorrect, but either way, these speakers are still awesome!
 
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