This video will be elementary to most.
It's good to see it demonstrated.
Why post it here?
First Watt.
How loud is 1 Watt (with an 87db Loudspeaker)? - YouTube
It's good to see it demonstrated.
Why post it here?
First Watt.
How loud is 1 Watt (with an 87db Loudspeaker)? - YouTube
87db/watt tell tiy all you need to know...
with this speaker you will measure 87db at 36" or 1 m depending on what was used to provide the 87db with a 1 watt input (2.83 volts input)
with this speaker you will measure 87db at 36" or 1 m depending on what was used to provide the 87db with a 1 watt input (2.83 volts input)
Hmmm, the main flaw in that video is the method of determining that it was playing at 1W. There could have been many peaks that were well over 1W that were not registering depending on the sampling rate of the multimeter.
Without doing a constant tone (at 0db) and setting the level based on that, I think it is rather arbitrary.
Tony.
Without doing a constant tone (at 0db) and setting the level based on that, I think it is rather arbitrary.
Tony.
if you want to use a small amp that only has a watt or so of power you will need a pair of speakers with about 96 db or more (always better) of efficiency or you will need a pair of subs if you decide to go lower so far as efficiency is concerned. You may still find it does not spin your propeller. Moral of the story is go listen to the speaker you are interested in or one that is similar on the amp you want to use or one which is also very similar and judge for yourself if this sort of combination is going to work for you and the music you like to play. First had experience is what you need, all the on line comments in the world will not tell you what you need to know.
He is using a multimeter to measure audio from the amplifier, does he realise that the multimeter is band limited on its ac range (40Hz - 500Hz) and only valid in manual range mode.
Notice at the 3:26 minute mark of the video he's yelling out that the amp is putting out 2 watts but fails to notice the multimeter is displaying 9.06volts that's closer to 10 watts than 2 watts and that is based on the band limited response of the multimeter and its ability to keep up with the changing waveform as the multimeter is expecting a continuous sinewave.
Who really knows what the amplifier output voltage really is, what we do know that its significantly more than 2 watts.
I couldn't be bothered to calculate the required power level from the amp to drive the loudspeaker to produce the dB level displayed on the sound level meter, but something is wrong with his maths (at the 3:18 minute mark) if 1 watt from a 87.5dB (1 watt) speaker is producing 96dB peaks on the sound level meter from at least 2.5meters from the speaker.
Notice at the 3:26 minute mark of the video he's yelling out that the amp is putting out 2 watts but fails to notice the multimeter is displaying 9.06volts that's closer to 10 watts than 2 watts and that is based on the band limited response of the multimeter and its ability to keep up with the changing waveform as the multimeter is expecting a continuous sinewave.
Who really knows what the amplifier output voltage really is, what we do know that its significantly more than 2 watts.
I couldn't be bothered to calculate the required power level from the amp to drive the loudspeaker to produce the dB level displayed on the sound level meter, but something is wrong with his maths (at the 3:18 minute mark) if 1 watt from a 87.5dB (1 watt) speaker is producing 96dB peaks on the sound level meter from at least 2.5meters from the speaker.
I agree with you guys, it's pretty obvious his setup is totally flawed. And not a single comment pointing this out under that video.😕
jeff
jeff
I try to use a peak detector instead to see what I really need.
With a tube amp, I take a full wave rectifier with enough PIV to not die and put across the primary side Add 1bout 1 microfarad on the other side of the bridge and see what I eventually come up with for voltage.
Remember to multiply voltage by .7 for RMS and figure power based on impedance.
Wondering if anyone has an easier way to do this.
With a tube amp, I take a full wave rectifier with enough PIV to not die and put across the primary side Add 1bout 1 microfarad on the other side of the bridge and see what I eventually come up with for voltage.
Remember to multiply voltage by .7 for RMS and figure power based on impedance.
Wondering if anyone has an easier way to do this.
In my experience, I found 1 Watt is quite load for a moderate room size, but it greatly depends on the speakers. Listening to music using efficient speakers, makes a huge difference.
Regarding the use of a multimeter to measure the audio voltage, unless one inspects the entire signal waveform for a specific time, one will never know whether there were music peaks beyond 1W.
Regarding the use of a multimeter to measure the audio voltage, unless one inspects the entire signal waveform for a specific time, one will never know whether there were music peaks beyond 1W.
Haven't watched the video so don't know what he used but my multimeter has a bandwidth of 100kHz.
He is using an Mastech MS 8217 , frequency range 40 Hz to 500Hz on AC measurement
what ever happens , we here all know that the Firstwatt are plenty enough and are the ones we like 😉
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what ever happens , we here all know that the Firstwatt are plenty enough and are the ones we like 😉
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You don't - in a small room. But remember that if you are really playing at 1 watt average power on music, then peaks can easily be 18 dB higher, or in the range of 63 watts. You'll need that headroom, whether 1 watt is loud or not.
Your multimeter may have a bandwidth of 100kHz but it will only measure sinewaves not complex waveforms.
Not to mention the laws of physics defying claims when he was yelling out 1 watt and the audio level meter is peaking over 96db at around 2.5 meters from a speaker with a sensitivity 87.5dB @ 1 watt.
The quote at 8:45 was laughable which he also gets wrong.
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I agree with the overall premise and conclusion, despite the measurement errors.
We all have different room sizes and some of us like music considerably louder than others, however a few watts is more than enough for the average room at "normal"* listening levels.
* levels that do not produce cumulative hearing loss
We all have different room sizes and some of us like music considerably louder than others, however a few watts is more than enough for the average room at "normal"* listening levels.
* levels that do not produce cumulative hearing loss
