This is the point that we are trying to make.
A 5W amp that is capable of 50W peaks ir MORE than sufficient for domestic listening.
Some interesting new posts and points. As Andrew points out, drop your speaker sensitivity by 10dB and you'll need 10X the power to hit the same sound levels. That can make a big difference. Power needed can get big, fast. Small subwoofers are a good example of that. Folks who need a lot of power usually have inefficient speakers that need the power. Some very good speakers are built that way, E.G. the Magnapan.
Gogitech - I suspect that you were missing the real peaks when you measured. They can be pretty fast and almost impossible to catch with a DVM. I looked at my version of Money (there are so many remasters) and it has an average level of -14dB, pretty hot. Thru the loud sections the average is only 12dB below peak. (see below) Still, of your peaks really were 2.5V that would put the average way down at 1/2 volt, or 31mW. I'd be as skeptical as a.wayne on that one. Possible, but not likely. I've attached a zipped MP3 of a 120Hz tone at -14dB. It matches the average level I found on the Money track from the CD layer of the DSOM SACD version. If you can, please measure that at the same volume setting as you played Money.
The "tricK" with the 120Hz tone is that it's easy and accurate to measure with a DVM. And it's recorded at the same average level as most music. You might want to sneak into it if you don't think your speakers will handle it, turn it up slowly. Not likely to be a problem, if music at the same level is not.
Gogitech - I suspect that you were missing the real peaks when you measured. They can be pretty fast and almost impossible to catch with a DVM. I looked at my version of Money (there are so many remasters) and it has an average level of -14dB, pretty hot. Thru the loud sections the average is only 12dB below peak. (see below) Still, of your peaks really were 2.5V that would put the average way down at 1/2 volt, or 31mW. I'd be as skeptical as a.wayne on that one. Possible, but not likely. I've attached a zipped MP3 of a 120Hz tone at -14dB. It matches the average level I found on the Money track from the CD layer of the DSOM SACD version. If you can, please measure that at the same volume setting as you played Money.
The "tricK" with the 120Hz tone is that it's easy and accurate to measure with a DVM. And it's recorded at the same average level as most music. You might want to sneak into it if you don't think your speakers will handle it, turn it up slowly. Not likely to be a problem, if music at the same level is not.
Of course! 😛
Attachments
Nice plot showing compression.
Note all the peaks above the one of mONEy.
They all reach the same Vpk. Coincidence or compression?
Note all the peaks above the one of mONEy.
They all reach the same Vpk. Coincidence or compression?
As far as I could tell there wasn't any clipping here. It is, after all, a premium edition. 🙂
There isn't a lot of dynamic range, but it's loud Rock, so there shouldn't be. Compressed? Sure. But that's part of the genre. No idea if it's more compressed than the original.
EDIT: I take that back. Zooming in on the rage you pointed out, I see what looks like hard limiting. Zooming in further shows either clipping or a brick wall limiter. See attached as typical of that section. Funny thing is, that flat top is not at 0dB, it's at -0.7dB. There's still a bit of room above it.
There isn't a lot of dynamic range, but it's loud Rock, so there shouldn't be. Compressed? Sure. But that's part of the genre. No idea if it's more compressed than the original.
EDIT: I take that back. Zooming in on the rage you pointed out, I see what looks like hard limiting. Zooming in further shows either clipping or a brick wall limiter. See attached as typical of that section. Funny thing is, that flat top is not at 0dB, it's at -0.7dB. There's still a bit of room above it.
Attachments
Everyone is missing the point here.
For a loud listening experience you only need about 5W of clean Class A power.
Peaks may take you up to 50W or so,
Take your daughters boom box. It is only about 500mW but its LOUD.
For a loud listening experience you only need about 5W of clean Class A power.
Peaks may take you up to 50W or so,
Take your daughters boom box. It is only about 500mW but its LOUD.
Agree and yes the systems is down , i'm doing updates to the speaker i need another 3-4 db increase in sensitivity and my monitors are at another house miles away.
Regarding the choice of recording i find such recordings to have not much in the way of dynamics and a poor choice, Eagles hotel california , live would be a better choice for dynamics, at the end there is a sustained increase with the crowd response, yet better choice is Hugh Masekela, coal train , early 90's release that is not compressed or The Sarafina CD.
Very difficult to appreciate any of those with flea power...🙂
Andrew has done a better job than i , in explaining the necessity for more power than we think , i'm sure most are getting "loud" sound from their flea power equipment, but i'm also aware of the quality of such sound..
Regards,
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Are we?
An amplifier that can supply 5W RMS (class A, B, A-B or D) will supply 10W, peak. Amplifier power is rated on a sine wave. A sine wave has a peak value 3dB higher that its RMS value. Simple, and easy to measure. If the amplifier can sustain 5W rms, then it can supply 10W peak - (sometimes a bit more, depending on the power supply.)
Yes, 500mW can be very loud. A 5W amplifier is not going to supply 50W peaks, unless there is something new I don't know about.
The subject of the thread is "How much power do you really need?" There are easy ways to actually measure that.
Maybe. Wouldn't that depend on the room and speakers? Even most dynamic recordings don't have an average to peak difference or more than 22dB. Meaning for all but the most extreme recordings, you don't need more than 25dB of headroom over the average level. Usually much less. Just figure out what the average power level is and you'll know what peak levels you need. Simple. It may be 10 watts, or it may be 200 watts.
If you are regularly blowing 10A fuses at the speaker, then you are regularly hitting 400W or more (into 4 ohms). Or maybe you have an impedance dip down to 2 ohms or less. Have you checked?
1ohm from 300hz to 22k ....
No i have heard the high sensitivity stuff with flea power , spent alot of time years ago listening to the ongaku 1 watt , first watt that counts theory🙂, it does not work for me , i find most high sensitivity speakers to be unbalanced, shouty in character and not my cup of tea.
High sensitivity from large multiple drivers works and is the only way to do high sensitivity to me, they have good balanced and grow in size and lower dynamic distortion, unlike Small single drivers or 2 way type high sensitivity which do not, those tend to have poor dynamics IMO (stay big and loud ) and size's wrong,
regards,
No i have heard the high sensitivity stuff with flea power , spent alot of time years ago listening to the ongaku 1 watt , first watt that counts theory🙂, it does not work for me , i find most high sensitivity speakers to be unbalanced, shouty in character and not my cup of tea.
High sensitivity from large multiple drivers works and is the only way to do high sensitivity to me, they have good balanced and grow in size and lower dynamic distortion, unlike Small single drivers or 2 way type high sensitivity which do not, those tend to have poor dynamics IMO (stay big and loud ) and size's wrong,
regards,
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Ah, thanks! So you could be blowing fuses at 100 watts. That's 10 volts into 1 ohm.
From that I would say you are running an average level of about a volt, just like me. You're just using more power because of the lower impedance load.
It will be interesting to know your actual voltage levels once you're back up and running.
From that I would say you are running an average level of about a volt, just like me. You're just using more power because of the lower impedance load.
It will be interesting to know your actual voltage levels once you're back up and running.
Yes that's about right 100 watt rms sustained will blow the fuses .... with the changes in sensitivity for the speakers and a dedicated 1 ohm amplifier , we will see.
I'm not sure if I was supposed to run the test with 120Hz or not, but I did anyway...
To summarise, 98dB @ 1W, Money played sensibly loud (I guess this is down to opinion, but it was loud enough to enjoy the music) 2.5V peak on the scope. 120Hz sine played at pretty close to the same volume reads 0.75V on DMM. This would be a power of 70mW per speaker, a quick estimate of 85dB average at the listening position. Does this seem reasonable?
Brian.
To summarise, 98dB @ 1W, Money played sensibly loud (I guess this is down to opinion, but it was loud enough to enjoy the music) 2.5V peak on the scope. 120Hz sine played at pretty close to the same volume reads 0.75V on DMM. This would be a power of 70mW per speaker, a quick estimate of 85dB average at the listening position. Does this seem reasonable?
Brian.
Yeah Brian, sounds about right to me for 98dB speakers. I'd be at about 1V, but am at a lower efficiency than you. Thanks for testing. 
my friends
We must guard our ears
careful with the volume
I was sound engineer in a rock band
if we feel is because we are alive
not much more
health
We must guard our ears
careful with the volume
I was sound engineer in a rock band
if we feel is because we are alive
not much more
health
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