Any truth to speakers being better with a more powerful amp?

[andrew]

This topic is also of interest to me as I attempt to find a power amp to drive some vintage stand-mount speakers that go down to 3Ohms at 150Hz. Is it as simple, for modern amps, as follows:

1. If the speaker has a benign impedance curve the relevant amplifier criteria are just the power required to meet SPL requirements and distortion

2. Alternatively, if the speaker presents a difficult impedance curve (e.g., very low impedance or high phase angles) then the ability of the amplifier to deliver the required current at low impedances is also a criteria

 

[ahofer]

It’s from the Latin “currere”, meaning “run”.

Which I *should* know given six years of Latin...ending 41 years ago. In my defense, the 'ou' in the French version gave me the impression it might have a different etymology.

 

[Martin]

My completely subjective, seat of my pants response is that there is no replacement for displacement. In the audio world that's the more watts you got the better. I run 1200 watt ICEpower monoblocks on my Von Schweikerts. Nothing wrong with having a little headroom.

Martin

 

[Ze Frog]

That's a 6.3 kW amp...

That would be for whole frequency spectrum, but seeing as transient peaks should largely be rather specific and narrow frequencies at any given point, it's actually really far less. Plus despite an amp having say 100 Watts available say, in theory because not each frequency is using the same amount of power at the same specific time there is usually a fair bit of headroom up to that point, and then there's the ability to provide power usually quite a bit beyond really albeit briefly. So really the headroom required isn't as large as the math's would dictate just because of the massive variance between frequencies.

Even cheap and nasty gear actually has quite the headroom for very brief periods, that's why some el cheapo gear would use really wild claims back in the day, in the 90"s I seem to remember really crappy stuff claiming say 500 Watts, think it would say like 500W PMPO(?) or something along those lines. Remember reading stories back then about how it was literally based on a max reading for a few milliseconds or something ridiculous, but apparently despite being seemingly false advertising it was deemed a valid measurement in a lot of stuff on that technicality of it could reach that target for a very very brief interval at likely a specific frequency in the band that would likely be very easy to manage.

Back to decent stuff we are all spoilt by today, even the cheap stuff is absolutely well and above what could be had for the equivalent price in the past, my rule of thumb is always what is my maximum volume going to be, how many Watt's does that equate to, then ideally I try to make sure I have double the required.

 

[Ze Frog]

My completely subjective, seat of my pants response is that there is no replacement for displacement. In the audio world that's the more watts you got the better. I run 1200 watt ICEpower monoblocks on my Von Schweikerts. Nothing wrong with having a little headroom.

Martin

Always better to have more than not enough, that's for sure. As long as you can control the volume dial sensibly no damage to be done.

I think a lot of people not in the know are scared of having an amp with say 200W with a 50W speaker and think they'll blow it up, which is actually quite amusing as you are more likely to do damage with a 25W amplifier and the clipping taking out a tweeter. A speaker within reason, given clean power will take far more than one might expect.

 

[Sokel]

That's a 6.3 kW amp...

Right on Genelec's money,they must have read the same article

 

[Sokel]

My completely subjective, seat of my pants response is that there is no replacement for displacement. In the audio world that's the more watts you got the better. I run 1200 watt ICEpower monoblocks on my Von Schweikerts. Nothing wrong with having a little headroom.

Martin

I already run a 1200as2 +300a2 in stereo for my semi-actives,don't temp me to double them !

(the worst thing thing is that is dead easy to do it,I don't even need new cases)

 

[Blumlein 88]

Easily rectified.

https://www.worldradiohistory.com/Archive-All-Audio/Archive-High-Fidelity/80s/High-Fidelity-1981-06.pdf

View attachment 341054

Thank you for this. @anmpr1

Mentioned about the new test protocol for sensitivity, in this same issue is a description of the new testing protocol for speakers. They previously used an anechoic chamber, but were switching to in room measurements using computer manipulation by an Apple computer.

 

[Blumlein 88]

This topic is also of interest to me as I attempt to find a power amp to drive some vintage stand-mount speakers that go down to 3Ohms at 150Hz. Is it as simple, for modern amps, as follows:

1. If the speaker has a benign impedance curve the relevant amplifier criteria are just the power required to meet SPL requirements and distortion

2. Alternatively, if the speaker presents a difficult impedance curve (e.g., very low impedance or high phase angles) then the ability of the amplifier to deliver the required current at low impedances is also a criteria

Pretty much correct on this.

Stereophile uses an EPDR test result now in speaker reviews. Effective Peak Dissipation rating. In short it is an impedance in pure resistance equal to the max dissipation across the output of the power amp. So a nearly resistive load like a Maggie which is 4 ohms would get a 4 ohm rating, while something with a lot of reactance that might have an impedance of 4 ohms with considerable phase shift would get a lower than 4 ohm rating.

If you want the long explanation here it is:

Heavy Load: How Loudspeakers Torture Amplifiers

Why, in loudspeaker reviews, is impedance measured (assuming that the magazine in question bothers to measure anything)? Generally, for one principal reason only: to establish whether the speaker presents an "easy" or a "difficult" load to its partnering amplifier. In the design context, much...

www.stereophile.com

For an example of rather difficult load see their recent review of a Q-Acoustics speaker.

Q Acoustics 5040 loudspeaker Measurements

Sidebar 3: Measurements I used DRA Labs' MLSSA system, a calibrated DPA 4006 microphone, and an Earthworks microphone preamplifier to measure the Q Acoustics 5040's quasi-anechoic behavior in the farfield. (The 5040's manual doesn't mention an optimal listening axis, so I examined the farfield...

www.stereophile.com

Generally with cone, dome and box speakers most people worry too much about this. With ESL's or ribbons you can run into more problems. Of course there is always the rather weird issue now and again from an oddball design.

 

[Nicolas_]

Doesn't that just mean keeping up with the times?

I didn't know French had the same synonym.

You are correct, "être au courant" = being aware of/up to date with the current knowledge.
Exactly the same multiple meanings as in English (electrical current, sea currents... basically whatever flows)

 

[voodooless]

That would be for whole frequency spectrum, but seeing as transient peaks should largely be rather specific and narrow frequencies at any given point, it's actually really far less.

It doesn't matter, if you want that headroom, you need that power, no matter how short that may be.

Plus despite an amp having say 100 Watts available say, in theory because not each frequency is using the same amount of power at the same specific time there is usually a fair bit of headroom up to that point, and then there's the ability to provide power usually quite a bit beyond really albeit briefly. So really the headroom required isn't as large as the math's would dictate just because of the massive variance between frequencies.

Again: if you want 18 dB of headroom above 100W, you'll need 63x the base power. Physics doesn't change that. You need to be able to provide the voltage and current, otherwise, you will not have that headroom.

Now the real question is: do we realistically need 18 dB of headroom above 100W? I guess not. You usually don't need 100W to run an average speaker in an average room at normal average listening levels (let's say < 86 dB). You'll need only a few watts for that. Add 18 dB on top of that, and you'll end up with a much more realistic number of what is actually needed.

 

[Chr1]

I am curious as to why excursion protection isn't built in to good passive speakers? Most actives have this. Is there a reason, other than cost obviously?
Presumably it would ensure we could have the required headroom without as much risk.

 

[voodooless]

I am curious as to why excursion protection isn't built in to good passive speakers? Most actives have this. Is there a reason, other than cost obviously?
Presumably it would ensure we could have the required headroom without as much risk.

Because it's an active measure.

 

[Chr1]

Thanks. But presumably it could be useful? ie semi-active, where you choose the external amplification but driver protection is built in to the speakers.

Guess that there's a good reason why it's either passives with a fuse/bulb, or fully active with more advanced protection.

I will need to read up on this obviously

 

[DanielT]

....an average speaker in an average room at normal average listening levels (let's say < 86 dB). You'll need only a few watts for that. ...

I know you voodooless know this, but for others reading it may be a tip.

A little OT. I know more people who said that, around "average speaker in an average room at normal average listening levels (let's say < 86 dB)."
Yes maybe. A matter of taste. Depends on the conditions too.
In my small combined living / listening room 86 dB more than normal listening volume.

I urge everyone to at least download a free dB app meter and test this at home. Just to get a feel for this with dB, sound pressure, listening volume. Do it first before you spend a lot of money on a powerful amp, whose potential maybe then will not be used anyway.

 

[Nicolas_]

I urge everyone to at least download a free dB app meter and test this at home. Just to get a feel for this with dB, sound pressure, listening volume. Do it first before you spend a lot of money on a powerful amp, whose potential maybe then will not be used anyway.

Good advice, I did just that for the first time a couple of days ago, for the same reasons: trying to understand what power I would realistically need. I found that ~70db (given by the app I downloaded at my listening position) was already plenty of sound, and a higher volume than I would listen in probably more than 90% of the cases

 

[Nicolas_]

Also, I tested it first at 4m from my speakers, than got closer all the way to 1m. I expected the dB reading to increase by 12db, it did not (barely moved). Could it be that this is due to me seating inside a "box" - speakers 30cm from the wall on one end, seating position 4m away against the opposite wall - and the sound bounces off each sides and gets diffused (if that's the right word) more evenly within the room?

 

[fpitas]

Also, I tested it first at 4m from my speakers, than got closer all the way to 1m. I expected the dB reading to increase by 12db, it did not (barely moved). Could it be that this is due to me seating inside a "box" - speakers 30cm from the wall on one end, seating position 4m away against the opposite wall - and the sound bounces off each sides and gets diffused (if that's the right word) more evenly within the room?

Probably. The microphone has no idea those are reflections, so happily measures them.

 

[DanielT]

Also, I tested it first at 4m from my speakers, than got closer all the way to 1m. I expected the dB reading to increase by 12db, it did not (barely moved). Could it be that this is due to me seating inside a "box" - speakers 30cm from the wall on one end, seating position 4m away against the opposite wall - and the sound bounces off each sides and gets diffused (if that's the right word) more evenly within the room?

That's because your listening room acts like a reverb chamber (reflections as fpitas mentioned in post above). Therefore, with the calculator below in the link
regarding how much amp power you need, you don't need to put in more than 1.5-2 meters. It depends on the type of room you have (how much furniture, carpets and so on ) and how narrow the speakers' dispersion pattern is, but roughly so. You can easily measure that at different distances in your room, as you did, and realize how it works in practice.

How much power does an amplifier need with this type of range of dynamic music

Feel free to use this calculator. Add sensitivity to the speaker and then tell which effect you have chosen and why. Weigh in that you want some headroom. http://www.mh-audio.nl/Calculators/REAP.html You can select music from this list. Or something else, but in that case tell us how you...

audiosciencereview.com

If you use this type of calculator, keep in mind that an extra speaker adds 3 dB.

Edit:
However, take your speakers outside and measure in an open field and you will notice a clear difference how the sound level decreases with distance. Intuitively, most people already know this, so there is no need to measure it.
(indoor vs outdoor -sound pressure)

 

[amadeogt]

Sorry if I missed this, but: OP, which Denon AVR are you using? Does it have a 4 ohm rating in the specs?

The reason I ask is because some Marantz AVRs are not rated by the manufacturer for 4 ohm operation - which means they might have issues with that.

I have an SR 5005, and it isn't able to properly drive my Monitor Audio RX8s (4 ohm nominal). Weak and undefined bass.

Adding an external amp, either a cheap Aiyima A07 or my old Marantz PM8003, fixes the issue.