View Full Version : speaker max DB. Q:
Hereis my confusion.
If a speaker is 92 DB.@1 watt
95 DB. at 2watts
98 DB. at 4 watts
101 DB. at 8 watts.
104 DB. at 16 watts
107 DB. at 32 watts. Right guys.
And the speaker is rated 25 to 125 watts continuos power or RMS.
and the max SPL per pair is 106 DB.
DOSE THAT MEAN MORE POWER DOSEN'T MAKE THEM ANY LOUDER?
OR THE 3DB. gain when you doubble power is not right at all?
So they will be as loud at 32 watts as with 125 watts?
Dose wattage just create heat at some point?
It probably means that at 106dB (about 30W) the speaker meets the other characteristics (frequency response linearity). Above this, things are out of specs.
As for the "max power" figure (125W) it must refer to speaker's destruction limits. But bare in mind there's no international standards on this...
That's how I see it : this speaker accepts 30W max peak power.
It probably means that at 106dB (about 30W) the speaker meets the other characteristics (frequency response linearity). Above this, things are out of specs.
As for the "max power" figure (125W) it must refer to speaker's destruction limits. But bare in mind there's no international standards on this...
That's how I see it : this speaker accepts 30W max peak power.
That seems to make sence to me.
I found some cool max. spl calculators.
http://www.fuzion.co.uk/support/Calcs/Spl.htm
http://myhometheater.homestead.com/splcalculator.html
HighFidelityGuy
16-03-2010, 16:38
You also have remember that a 100W RMS amplifier isn't producing 100W RMS all the time at any listening level. The only way you could get it to produce 100W would be with 0dB sine wave, probably at 1KHz. The 0dB part means that the sine wave is maximum amplitude.
You would then have to turn the amp all the way up to somewhere near full volume where the amp is producing full power without any distortion. Obviously this would never happen during normal listening, so the amp will only be using a small part of it's capabilities most of the time. The rest is there in reserve for sudden transients in the music.
Also, just because a speaker can make 92W with 1 watt at 1 meter doesn't mean it can make 120 dB when given lots more power. Speakers aren't perfect transducers as they will dissipate some of the power as heat. So if you gave it enough power to make 120 dB the voice coil may melt, the cone/surround could tear or the voice coil former could bottom out and hit the back plate. None of which are good.
Speakers have to be specifically designed to produce very high sound pressure levels (SPL). In doing this they rarely sound particularly good.
The wattage ratings on the back of speakers are really just a guideline. Also, it's often safer to use an amp that's more powerful than recommended than one thats very low powered (when using standard speakers). This is because you'd have to turn the low powered amp up much higher to get the desired listening level. This makes the possibility of running the amp into distortion much more likely. This can make the voice coils get hot and cause them to break down over time. This is why you need special very sensitive speakers to use with low powered amps like SET's. That way you can get the high volume from a lower volume setting on the dial.
The key thing is to make sure your amp is suitable for your speakers or vice versa. You want your normal listening level to be at around 12 o'clock on your volume dial as that's where volume controls sound the best. If you can't get the dial that high before it's too loud you have too much gain. That's when you need an attenuator like THESE (http://www.rothwellaudioproducts.co.uk/html/attenuators.html). I've just ordered one to solve that exact problem in my system.
With solid state amps I usually look at the speakers RMS rating and then use an amp that's at least double that. That way your normal listening level is more likely to be making your amp produce somewhere near that output. With valve amps you only need about half the power of an equivalent solid state to get similar results. I'll not go into why as it's a bit complicated and I've already waffled way too much. :ner:
That was probably way more info than you needed but I needed a break from work. :lol:
That seems to make sence to me.
I found some cool max. spl calculators.
http://www.fuzion.co.uk/support/Calcs/Spl.htm
http://myhometheater.homestead.com/splcalculator.html
Hey, that's cool !!! Thanks Jeff. :)
(I still have my *paper* (printed) SPL calculator... shame on me :o)
With valve amps you only need about half the power of an equivalent solid state to get similar results. I'll not go into why as it's a bit complicated and I've already waffled way too much.
Dave,
Please do, as I don't understand why valve gear 'sounds' louder than the solid state equivalent.
Regards
Hi Dave,
Apart from everything else you've written, I particularly agree with this:
The key thing is to make sure your amp is suitable for your speakers or vice versa. You want your normal listening level to be at around 12 o'clock on your volume dial as that's where volume controls sound the best. If you can't get the dial that high before it's too loud you have too much gain.
...And I would add that from the 12 o'clock position, if the gain structure of the system is correct, you should be able to turn the volume control of the amplifier up to nearly maximum, so that taking full advantage of the dynamic range available on good recordings is possible, and before any clipping takes place. Basically at that level, the sound should be very loud but not distorted.
This is exactly how things are in my own system.
There are far too many systems (and equipment) these days which go loud far too quickly, saturating the sound in the process, and where the incorrect gain structure is in place, and the owner has an inability to use the full range of the volume control. Music will never sound right (or natural) that way. The trouble is though, people don't know what's right until they can hear what's wrong - and appreciate why this is so.
Marco.
Dave,
Please do, as I don't understand why valve gear 'sounds' louder than the solid state equivalent.
Regards
Some would tell you it's because of the huge amounts of added distortion coupled with soft-clipping :door:
Aye, and that someone would be an ignorant and deluded arsehole like Ashley James! :ner: :lol:
Marco
Soft clipping is certainly a possible cause. As for distortion, some should look at the figures of some high-praised (technologically and "sonically") class-D amps that dare to print 10% figures on their specs without having *any* objectivist finding this incredible.... :lol:
No Regrets
16-03-2010, 23:00
Hi Dave,
Apart from everything else you've written, I particularly agree with this:
Quote:
The key thing is to make sure your amp is suitable for your speakers or vice versa. You want your normal listening level to be at around 12 o'clock on your volume dial as that's where volume controls sound the best. If you can't get the dial that high before it's too loud you have too much gain.
...And I would add that from the 12 o'clock position, if the gain structure of the system is correct, you should be able to turn the volume control of the amplifier up to nearly maximum, so that taking full advantage of the dynamic range available on good recordings is possible, and before any clipping takes place. Basically at that level, the sound should be very loud but not distorted.
This is exactly how things are in my own system.
There are far too many systems (and equipment) these days which go loud far too quickly, saturating the sound in the process, and where the incorrect gain structure is in place, and the owner has an inability to use the full range of the volume control. Music will never sound right (or natural) that way. The trouble is though, people don't know what's right until they can hear what's wrong - and appreciate why this is so.
Marco.
I think we also have to keep in mind the types of volume controls or attenuators being used........is it a wiper or stepped; is it shunted, series, or ladder? These have variables to be considered.
Don (No Regrets)
Hi Don,
Indeed. I have a shunted stepped attenuator, and you're right, the type of volume pot used does make a difference, but whichever one is used, the end result within the circuit should mean that you are able to use the full range of the control, not merely half of it (or less)...
Like Dave correctly says, pots sound best when used more 'wide-open' than closed - i.e. at the 12 o'clock position for normal listening, and at around 5 o'clock for maximum volume before clipping.
If the sound distorts before that point has been reached, then it's likely the incorrect gain structure is in place and music will tend to sound over-modulated/saturated at levels before the full dynamic range of recordings is realised. This of course varies depending on recordings, and presumes they have a wide dynamic range in the first place, which is sadly not always the case these days!
Marco.
Hi Marco,
Agree with you that the full usable range of the volume control should be such that for normal listening levels the control is around the 12 'o' clock position. I don't believe however that the actual type of volume control (series, shunt or ladder) makes much difference.
What is important is the attenuation law (i.e. linear or logarithmic). Most volume controls are logarithmic, as that is closer to how the ear peceives changes in loudness.
Either way if you find you're listening to your system with the volume control at say 9 'o' clock, then your amp has too much gain, conversly if at 3 'o' clock too little. Changing the input to one of a different sensitivity (if available) will usually sort things out.
Regards
Agreed, Barry. It was Don who brought up the issue of volume controls, and I could see where he was coming from, but like you say, if everything else is right it shouldn't make much difference :)
Marco.
No Regrets
19-03-2010, 22:10
Yes, it was me that brought up the issue of volume controls. I brought up this issue because I felt the following quote was too much of a "blanket statement".
Quote:
".....You want your normal listening level to be at around 12 o'clock on your volume dial as that's where volume controls sound the best......"
From my understanding, there is a big difference in volume controls. I agree that when using a "pot" or "series" type control that the signal will be more pure the higher the control is. For example, with a series type control you have many resistors in series. The positive leg sees a portion of the resistors depending where the control is at the time. In essense, the lower the volume control the more resistors it sees(less pure), and conversely, the higher the volume control the less resistors it sees (more pure). However, the ground leg still sees all of the resistors, all of the time.
With a "ladder stepped" attenuator, all though there are many resistors connected to the control, at any given spot on the control the signal only sees one resistor to the positive leg and only one resistor to the ground leg thereby insuring a pure signal no matter where the volume control is. With this type of control, the sound quality of the signal is the same whether the dial is at 10, 12, 2 o'clock or where ever it happens to be.
This was the only point that I was trying to convey with my comment.
Warmest regards,
Don (No Regrets)
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