Is More Watts Better?
Version 6:
Consider two amplifiers of extremely similar design and configuration to each other, 200W and 30W respectively.
Each is optimized for their own respective power output, set to the same perceived loudness (SPL). They are any type (Class D, tube, or solid state).
Will each amplifier have the same SQ, same battery efficiency, and no other qualitative or quantitative, subjective or objective, acoustic or otherwise, benefit of one over the other?
Loudness:
Loudness - Wikipedia
SQ:
Defined how you, listener, scientist, analyst, or hobbyist, define sound quality. If that includes lab tests, great. If not, fine. Could be distortion, headroom, resolution, transient response, bass response, frequency response, and any other parameters of interest.
Other benefits:
non-acoustic factors, like efficient use of power supply (eg for battery considerations).
SPL:
is set, presumably, by adjusting input amplitude.
Sweet Spot:
I wonder if each amp's SPL sweet-spot isn't different.
Version 3:
Say you're comparing two amps. They are the same type of amp (class D, solid state, or tube). Same design or chip-family. Same manufacturer. Same factory. Same production month. It's considered a high-quality amp.
You're feeding each amp their optimum supply voltage and current. The values and ratings of components, and sizes of traces, wires, and connectors are optimized, for each amp. Their respective heat-sinking is optimized.
One is 30W, the other 200W. The 200W amp is just the big brother to the smaller amp. They're as similar as possible, but just different
You set the 30W to it's optimum volume for best overal SQ. It's volume sweet-spot.
Then you set the 2000W to the exact same decibel volume as the 30W. They're equally loud.
Will one sound better? How? Why?
Version 1:
is there any benefit to driving a given speaker with more watts?
assuming a 50W amplifier can drive the speaker to max capability, will a 100W amplifier thru same speaker, at same perceived volume level, sound better?
Eg, less distortion, faster transient response, more efficient, etc.
to clarify: i'm not over-driving anything.
i know this is somewhat apples to oranges, assume:
- both amplifiers powered with their respective recommended power-supply.
- similar amplifier design. Main difference: one is more watts. Say, 30W vs 50W. Or 50W vs 100W.
- same speaker driver, assume compatible with both amplifiers.
- comparing each amp driving the speaker to same perceived volume-level.
- It's a "medium" volume-level, meaning doesn't clip on either amp, but not very quiet either.
thx
Version 6:
Consider two amplifiers of extremely similar design and configuration to each other, 200W and 30W respectively.
Each is optimized for their own respective power output, set to the same perceived loudness (SPL). They are any type (Class D, tube, or solid state).
Will each amplifier have the same SQ, same battery efficiency, and no other qualitative or quantitative, subjective or objective, acoustic or otherwise, benefit of one over the other?
Loudness:
Loudness - Wikipedia
SQ:
Defined how you, listener, scientist, analyst, or hobbyist, define sound quality. If that includes lab tests, great. If not, fine. Could be distortion, headroom, resolution, transient response, bass response, frequency response, and any other parameters of interest.
Other benefits:
non-acoustic factors, like efficient use of power supply (eg for battery considerations).
SPL:
is set, presumably, by adjusting input amplitude.
Sweet Spot:
I wonder if each amp's SPL sweet-spot isn't different.
Version 3:
Say you're comparing two amps. They are the same type of amp (class D, solid state, or tube). Same design or chip-family. Same manufacturer. Same factory. Same production month. It's considered a high-quality amp.
You're feeding each amp their optimum supply voltage and current. The values and ratings of components, and sizes of traces, wires, and connectors are optimized, for each amp. Their respective heat-sinking is optimized.
One is 30W, the other 200W. The 200W amp is just the big brother to the smaller amp. They're as similar as possible, but just different
You set the 30W to it's optimum volume for best overal SQ. It's volume sweet-spot.
Then you set the 2000W to the exact same decibel volume as the 30W. They're equally loud.
Will one sound better? How? Why?
Version 1:
is there any benefit to driving a given speaker with more watts?
assuming a 50W amplifier can drive the speaker to max capability, will a 100W amplifier thru same speaker, at same perceived volume level, sound better?
Eg, less distortion, faster transient response, more efficient, etc.
to clarify: i'm not over-driving anything.
i know this is somewhat apples to oranges, assume:
- both amplifiers powered with their respective recommended power-supply.
- similar amplifier design. Main difference: one is more watts. Say, 30W vs 50W. Or 50W vs 100W.
- same speaker driver, assume compatible with both amplifiers.
- comparing each amp driving the speaker to same perceived volume-level.
- It's a "medium" volume-level, meaning doesn't clip on either amp, but not very quiet either.
thx
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It's better to have more power than not enough. More headroom means running the amp at lower gain settings so that the speaker doesn't see over driven or clipping audio. Heathier for the amp and speakers. As long as you aren't pushing the speakers too hard, a larger amp within reason is a better match.
I think Your question is wrong formulated.
What do You mean by perceived volume level 1W / 5W / 50W ??
Say your perceived level is 50W. You just can't drive the same 50W speaker with a 100W amp at the same level or You'll blow the speaker. Try a car 12V lamp in a mains 120V socket. It blows !! (Analogy: The lamp is Your speaker and the mains is Your amp).
I believe this answers Your question:
Why Do Tweeters Blow When Amplifiers Distort?
What You can do is to wire the 50W speakers in series and connect them to a 100W Channel, or play at low <50W volume.
On large PA systems, the amps have usually more power in order when slightly clipped they don't shut off and ruin the show when for example the mic begins to squeal because of feedback or the drummer hits the drum more harder..
What do You mean by perceived volume level 1W / 5W / 50W ??
Say your perceived level is 50W. You just can't drive the same 50W speaker with a 100W amp at the same level or You'll blow the speaker. Try a car 12V lamp in a mains 120V socket. It blows !! (Analogy: The lamp is Your speaker and the mains is Your amp).
I believe this answers Your question:
Why Do Tweeters Blow When Amplifiers Distort?
What You can do is to wire the 50W speakers in series and connect them to a 100W Channel, or play at low <50W volume.
On large PA systems, the amps have usually more power in order when slightly clipped they don't shut off and ruin the show when for example the mic begins to squeal because of feedback or the drummer hits the drum more harder..
I think what he meant is,
If a speaker having 150 watt maximum power rating with 90db sensitivity is driven with 50 and 100 watt amp at the same level, do they have any noticeable difference in sound quality?
given both the 50 and 100 watt are the same amp just different power output
I'm curious about this as well
Most music will need ≥ 14db between rms and peak power to avoid ANY clipping. That means that a 100 watt amplifier can be cleanly operated at ~ 8 watts. That's enough for a VERY efficient speaker (≥100 db sensitivity) but probably lacking for most inefficient hifi speakers (~ 85 db sensitivity).
This is more complex question to which I wish to get an answer some day.
1. Some amplifiers, like class D have high levels of THD at low power, even if the amplifier has 0.01% at 100W, at 0.02W it has 1% of horrible distortion. Tube transformers are not immune to this. Most transistors have it.
SO a lot of amplifiers actually produce a lot of distortion with lower powers under 1 watt and then it improves.
The peak to peak signals sent to your speakers during a loud playing are mostly 1-5 watt at most. But you have to remember that this is a multiple signal and that it is inductive / reactive load!!!!!
The amount of power to drive an inductive load can be 2x or more! but imagine there are dozens of such signals at the same time?
So the real power required for the amplifier is at least 3 times the RMS peaks.
1. Some amplifiers, like class D have high levels of THD at low power, even if the amplifier has 0.01% at 100W, at 0.02W it has 1% of horrible distortion. Tube transformers are not immune to this. Most transistors have it.
SO a lot of amplifiers actually produce a lot of distortion with lower powers under 1 watt and then it improves.
The peak to peak signals sent to your speakers during a loud playing are mostly 1-5 watt at most. But you have to remember that this is a multiple signal and that it is inductive / reactive load!!!!!
The amount of power to drive an inductive load can be 2x or more! but imagine there are dozens of such signals at the same time?
So the real power required for the amplifier is at least 3 times the RMS peaks.
High power system, even with low volume opening, can transfer low frequency energy to long distance. With small power amplifiers, it is necessary to use high current power supply like in class-A. But what we hear is not amplifier's power. The decibel is a function of the distance between ear and speaker where within short distance (like headphone) we can feel a small speaker to sound as if a 15 inches speaker. But our practical listening distance is never constant.
It is one of our design objective to get a certain distortion level at several conditions. I think my main amplifier is 0.002% from may be 0.5W to more than 5W (it's associated with 0.2 to 1 volt input). I tried to make it linear like that.
thx for replies.
to clarify: i'm not over-driving anything.
i know this is somewhat apples to oranges, assume:
- both amplifiers powered with their respective recommended power-supply.
- similar amplifier design. Main difference: one is more watts. Say, 30W vs 50W. Or 50W vs 100W.
- same speaker driver, assume compatible with both amplifiers.
- comparing each amp driving the speaker to same perceived volume-level.
- It's a "medium" volume-level, meaning doesn't clip on either amp, but not very quiet either.
thx
to clarify: i'm not over-driving anything.
i know this is somewhat apples to oranges, assume:
- both amplifiers powered with their respective recommended power-supply.
- similar amplifier design. Main difference: one is more watts. Say, 30W vs 50W. Or 50W vs 100W.
- same speaker driver, assume compatible with both amplifiers.
- comparing each amp driving the speaker to same perceived volume-level.
- It's a "medium" volume-level, meaning doesn't clip on either amp, but not very quiet either.
thx
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You have to look at the distortion graph, and at what power level distortion starts to rise, and if you're keeping away from that point, then there will be no difference, or than the other aspects of the quality of the amps.
Keep in mind that most of the distortion comes from the speaker, so most bang for your buck you will get from getting better speakers not another amp.
First, I want to show you that it is practically impossible to have everything else equal...
An amplifier is specified only in certain conditions. It's THD can be specified at 1W or at its 'rated power'. THD is usually specified for 1kHz (it's sinewave not a musical signal) so that two amps have the same THD at 1kHz may differ at 100Hz or 20kHz. The load is usually specified at 8 Ohm (it's resistive and constant not like real-world speaker impedance) so that at lower resistance like 4 Ohm it can be better or worse.
Now, let's see how easy it is to get the 'identical' amplifier to have different maximum power...
Take a simple topology like single-ended design like ACA#1. With certain supply voltage you can get maximum usable power of say 6W. To maximize this number and to have the lowest THD at this number you have to make the signal clips 'symmetrical'. Let's say it is 0.1% at 6W and 0.05% at 2W. But you realize that you don't need 6W so you can opt for 0.3% at 6W (by allowing unsymmetrical clipping) but better distortion (0.02%) at 2W.
With common high power amplifier topology, the above situation may apply too. You can design an amplifier that is capable of 100W but your 'goal' is actually not that high power.
In practical situation, a higher power amplifier often performs better (not always). Can be because the transformer is bigger so can give instantaneous high current when have to drive lower impedance and/or low frequency.
When you know what to do and you design your own amplifier, smaller amp can sound better than bigger amp at close listening distance.
The real bottom line is your amp need to drive an inductive and reactive load with multiple signals (compounding). So the 100 W sine wave into 8 ohm has NO MEANING.
A 1 watt capable amplifier which can drive inductance and reactance without distortion could be way better than your 40 50 100 watt or whatever amp into 8R or 4R.
This is why in general a transformer output stage has 2X more power before you can hear the clipping than a purely transistor with resistor load.
A 1 watt capable amplifier which can drive inductance and reactance without distortion could be way better than your 40 50 100 watt or whatever amp into 8R or 4R.
This is why in general a transformer output stage has 2X more power before you can hear the clipping than a purely transistor with resistor load.
Correct, but (statistically) small amps usually have more difficulty driving low impedance speakers than bigger amps. That's why statistically/practically higher wattage amps perform better at low power than lower wattage amps.
Extreme example is a headphone. It performs very well at low power but with high impedance headphone. The higher the impedance of the headphone, the better the performance. But it will collapse driving 8 Ohm.
Amplifier's ability to drive a speaker is an important factor for amplifier's performance. Damping factor and Output impedance are variables often cited related to this although there is no perfect correlation between those.
A small amp usually is made of a pair of output transistor. To get higher wattage (with the same limited supply voltage) the number of the transistors must be increased and this increases the damping factor etc. So a bigger amp with paralleled output transistors often sound better (at low power) than a smaller amp with a single pair of output transistor.
But obviously those amps are not equal
When I made an amp for my own use, I started with the speaker and the listening room. I have never looked for more than 60W. This is a magical number for me because bigger amps (and this is the minimum) tend to have 'authority' or 'impact' (with my speakers) that I rarely have with low power amps.
this statement is a little confusing. You never look for more than 60W, and that is your minimum? sounds contradictory.
thx
For complex reason, high power amps often deliver bass quality usual small power amps cannot. 60W is the threshold with my living room size. But that's only related with bass. There are other benefits i'm after with small wattage. Mainly the ability to use high quality transistors with low ability to withstand high voltage needed for high power (Yes we can cascade several transistors but not without price).
Transistors with Vce(max)=45V is what i'm trying to use. Most JFETs have low Vgds as well, and suffers current leakage. Many small TO-220 mosfets are better sounding than the legendary IRFP240.
I think you don't understand, a speaker load is not only Z, impedance, simply a term to describe resistance vs frequency. I am talking about inductance and reactance, and capacitance I add.
A speaker coil with the XO isn't your typical light blulb type of load.
There are a lot of distortion effects when the signal varies in such a load.
There were threads with RMS measured and we concluded they are watt, however the phase changes too, Z, etc, which means the amp should be 3 to 4 times more powerful than the measured RMS at speakers.
P=V*V/R, at some frequency R is 10, amp doesn't need much power for 3 Vrms, if the impedance drops to 2 ohm then it is a lot more, add to this the power factor...
A speaker coil with the XO isn't your typical light blulb type of load.
There are a lot of distortion effects when the signal varies in such a load.
There were threads with RMS measured and we concluded they are watt, however the phase changes too, Z, etc, which means the amp should be 3 to 4 times more powerful than the measured RMS at speakers.
P=V*V/R, at some frequency R is 10, amp doesn't need much power for 3 Vrms, if the impedance drops to 2 ohm then it is a lot more, add to this the power factor...
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gabdx got it just right. To give you an more elaborate answer:
- More power does not mean better fidelity.
- Efficiency and power capacy goes hand in hand. Dynamic range is the key. You can easily calculate it, 1W can be enough, 300W might not be enough. Depends on your speakers, listening distance and your listening levels. Use a SPL calculator. If you don't have any imagination what level is appropriate, compare with a sound pressure level meter (there's an app for that..).
- Distortion at a certain level (spl or power wise) DOES matter. Don't be fooled by amp power x @ 10%THD, power y @ 1% is the value you'd be looking for (if, at all).
- What matters for others might not apply for you! Wattage does not matter AT ALL! Compare power at the impedance your speakers are rated. Okay, a lot speakers are rated at a wrong impedance but that's a value you can take an approache on it. Wattage is only of any significance if it's in relation of the impedance. If an amp is rated 100W @ 4 Ohm, you'll only get 50W at 8 Ohm. If an amp is rated 300W (wow, impressive!) @ 3 Ohm, it will only give you a bit over 100W @ 8 Ohm! If your amp is rated at 400W @ 2 Ohm, it will still only give you a hundred Watt at 8 Ohm!
- Power ratings do NOT give any information on how it does sound.
- Different chips do sound different. Again: Power rating does not provide any information on how good an amp sounds. That's dependent on the amplifier/modulation IC, the board implementation. I.e. TDA 7498 amps bring 100W per channel @ 6 Ohm (80W@8 Ohm), yet the merely 35W @ 8 Ohm TDA8932 sound a lot better.
the used speakers (YES, class D amps are very dependent on the impedance, especally in the treble!) and the power supply. And YES, the PS does have a huge impact on the sound!
Thx for observations. But, your comparison doesn't seem to address the comparison I'm asking.
Eg, I understand different chips sound different. The theoretical comparison I'm suggesting means SAME chip , that is same basic chip topology, same configuration, just different power. I understand the 8932 isn't available in different powers, but if it was? It's a theoretical comparison.
Likewise power supplies. I understand different power supplies sound different. I'm asking to compare SAME power supply design. Just scaled up in capacity to meet needs of more powerful amp.
Likewise listening setting. You're saying different settings will produce different results. Understood. I'm comparing SAME setting.
Thx
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