How loud is 1 Watt (with an 87db Loudspeaker)?

This video is presented by Harley Lovegrove, Technical Director of Pearl Acoustics loudspeakers.
With many people chasing massively powerful amplifiers for domestic systems, I thought it might be useful to demonstrate just how loud 1 Watt per channel is when it is pumped into a pair of 87db loudspeakers? In this video you will see how loud the music gets as we reach 1, then 2 and eventually 6 Watts of power into a pair of Sibelius SG loudspeakers. Please note - there is an error in the graphics at 03:33: 5,5V = 4Watts and not 2! Thanks to Claes Jegeras for pointing that out.
The piece of music featured in the video is 'Storm' taken from 'Summer' part of Antonio Vivaldi's Four Seasons. It is a rights free recording from: Audio jungle - Envatomarket

[@enzoamara]

likely one of the most useful and easy to understand videos on this topic ever made. well done.

[@PearlAcoustics]

Thank you!

[@ThinkingBetter]

@@PearlAcoustics An underpowered tube amp doing soft clipping at the peaks is by design, in my opinion, much inferior to a well-built transistor amp that can keep the signal shape intact at the peaks. But, if someone really likes having musical distortion added, then tubes can do the job. Any notion that adding a tube stage makes the sound more loyal to the master signal is bogus and a DSP can easily do what a tube can do in terms of incremental distortion effects (incl. do it better) for those wanting such sound.

[@PearlAcoustics]

@@ThinkingBetter I am absolutely in line with you here. However, sometimes scientifically ‘better’ does not sound so pleasing. It’s a very emotive area where I dare not intrude. As I say in my video. On a cold winters night with a glass of wine and the warm glow of two, very high quality tube amplifiers not running anywhere near their max - life is just perfect. But in the summer when I need to analyse exactly what is happening in a mix. Or just hear it ‘as it was’ - a top quality transistor amplifier is a must!

[@ThinkingBetter]

@@PearlAcoustics Well, whatever makes a person most happy should be the choice for that person when it comes to solid-state vs. tube. One factor is also what sort of music you listen to. I'm not against people adding some distortion or EQ. In fact, I often calibrate with EQ carefully to fix issues with room acoustics, especially in the bass, and a slight boost in the high treble above 12kHz to compensate for my hearing aging. The loss in high treble compensated with EQ is sort of quite similar to the loss of eye focus when watching TV having to use glasses to enjoy the full resolution.

[@Mikexception]

@@ThinkingBetter I would argue to that comparison to TV. We easy see lack of details walking in street or in TV which is annoying when we cannot read small writing. In listening in nature we experience everything correct ( except much loss of hearing) only producers of gear force us to think that we need limits which are not playing role in listening. Just as TV producers who say we need 8K or 18 K and with it we are getting slower refreshing, jumping movement of picture and faulty colors. Because more "K" is easy for them . Most people tend to believe in years of invention of tubes and transistors as proof of progress. Progress is newer. When it is obviously wrong then they try to push that they have "better ears". then those who are more satisfied with older. First even started to produce transistors emulation of bad tube amplifiers which make proof that it is bad. How about transistor's emulation of tubes in radio receivers? .What "ugly" would it present? My conclusion to audio discussion is that it would be valuable to understand Einstein's Relativity Theory up to the bottom before trying to understand audio. It would help to find the truth which is "nothing better done " .

[@nickwilliams1065]

The best explanation I have seen on how power output is related to volume, many thanks.

[@PearlAcoustics]

You’re welcome Nick

[@kittypeterson1896]

I learned more from this video and the comments below than I have from any other stereo-related video. Thanks for all the good information. I have an 35 year old JVC receiver with power meters that rarely go over 1 watt.

[@niventhamanna5563]

Finally one the best and honest explanations of how these parameters all work together. Great video!

[@paulaj2829]

After listening to so many different ways to understand db & volume this is by far the most understandable video i have watched.. keeping everybody happy is what music is all about..

[@PearlAcoustics]

Thanks! Totally agree 😉

[@mysock351C]

The video is a bit misleading (probably not intentionally, but still worth pointing out). Firstly using a DVM to measure the power output. This will provide a reasonable estimate of the overall RMS power, but it ignores the peak power. If an amp can only provide 1.41 watts (peak value of the RMS power output), you'll get quite a bit of distortion and clipping even at low volumes. Due to the high peaks of music, the amplifiers RMS power rating (we assume that the music is still sinusoidal and not an actual impulse, which it almost always is) will be what determines when the amplifier goes into clipping, and the peak power output will be significantly higher than the average output recorded with a DVM. While its true that some amps can provide a bit more over short spans (dynamic headroom) due to the reservoir capacitors, this is not always the case, especially with class-D topologies. With those, 50 watts is 50 watts, period. The second is the frequency content of music. Even with a properly set up system to have a flat response music with lots of low frequency content will chew through a watt with very uninspiring results. For music with most of the audio power confined to the mid-bass and midrange region, you can get away with one watt. But hit any lows or music with a heavy bass line and forget it. You'll get distortion, or at least an unsatisfying experience. The last thing is that hearing is logarithmic. A doubling of the power will _not_ appear to be a doubling of sound amplitude. This is evident in dB based volume controls. If you put a oscilloscope on the amp output, you'll notice the output voltage climbing like crazy even though the volume appears to increase linearly. Each 3dB increment will require TWICE as much power. You don't need hundreds of watts for the domestic hi-fi environment, but at least 25W RMS/channel is needed unless you only listen to classical or at low volumes. To do the test properly, you would actually need an oscilloscope that can measure and log the peak-peak voltage, as well as some ability to measure (or at least knowledge of) the reactive impedance of the speaker at the same time. A 4-ohm speaker is NOT 4 ohms at audio frequencies. Its usually 5-7 Ohms, or higher, depending on the speaker and enclosure due to the back-EMF of the voice coil. The nominal impedance will lead you to overestimate the actual power output when just using voltage, sometimes dramatically. While this works in their favor, its still not right. Without these, the actual RMS output is essentially unknown. While its still a reasonable demonstration, people shouldn't get the impression that a very low power class-A amp will give good results.

[@scottlowell493]

Yeah, sound output lot more complicated than just "87db/1w/1 meter". and "I have a 9 watt amp so I'm good!" that's far from a complete formula.

[@shinvergil]

Thx for the sane comment.

[@SomeTechGuy666]

"The second is the frequency content of music. Even with a properly set up system to have a flat response music with lots of low frequency content will chew through a watt with very uninspiring results." Nope. A woofer with an SPL of 87db will produce 87 db with 1 watt, just as a tweeter will. The reason you think woofers need more power is because you are probably using low efficiency woofers.

[@OxBlitzkriegxO]

@@SomeTechGuy666 human ears don't hear lower sounds as efficiently as they do midrange sounds. That coupled with the fact the woofers/subs are inherently less efficient due to design, are why low frequency sounds need more power.

[@OxBlitzkriegxO]

OP, you know just enough to sound ignorant to people who know more than you. Your wall of text us full of inaccuracies and ignorance.

[@SPEEDOFDOG]

What an eye opener. Thanks. I no longer possess watt envy.

[@matejgrim]

That was a lot of information put so simply... I love it!

[@kloug2006]

Surprising demonstration, I was not expecting that much SPL !

[@charlespetersonii6989]

Absolutely loved your explanation of the video especially Damping factor. Thank you 😁

[@marks.2909]

Very interesting and educational video , I would never have believed it . Many years ago I used a David Berning 1 watt per channel vacuum tube amplifier used to drive a pair of Klipsh RF-7 speakers with dual 10 inches woofers in each speaker . A friend laughed at the idea I would use such flea power on such large speakers , five seconds into the first cut of a Pink Floyd selection he was speechless though he knew nothing of the high efficiency of this speaker it turned out this amplifier was a beautiful match with this particular Klipsh speaker .

[@bphilbac]

That is some great and eye opening information. Thanks for posting.

[@stevefranks6541]

Greetings, If a picture is worth a 1,000 words, imagine what a video can do? Fantastic demonstration. I have a 6.8 watt SET amplifier and it is more than enough power for my 10x14 foot computer den with 92dB sensitivity bookshelf speakers. Thanks for the wonderful demo! It proves me right. As an aside, your delivery is so friendly and laid back, I feel as those I am just sitting with an old friend having a great casual conversation over a cupper. I love all your videos, especially about your growing up loving sound. And I learn a lot along the way!

[@PearlAcoustics]

Thank you Steve, very kind. There’s more on the way in 2021! Take care. Harley

[@JC-oz6xn]

Great job. Thank you. However, I do believe my wife goes louder with even less wattage! Some room treatment, clearly, is in order.

[@PearlAcoustics]

In an obtuse way, you have hit on an important point. Sound source, frequency range and timbre have a massive impact on us, sometimes even more than the content! This is something I will be covering in a later video on speaker placement

[@johnmills3163]

LOL ... my wife too 👍

[@mrupholsteryman]

Mine works on "what"age. 😀😇😎

[@WiiNV]

L🤭L

[@franklinhankel6168]

I've noticed the very same results with my wife, she has very high efficiency and can be driven quite easily, with my comments, even with very little power! But seriously, when I was a kid, we used to take a cheap RadioShack watt meter and hook it up through the speakers of our various crappy systems and we were amazed at how little the amount of wattage was, even when loud.

[@1974UTuber]

This is exactly why a properly built 12W valve amplifier coupled to high efficiency speakers sounds so awesome

[@jungtarcph]

87 is not that efficient though.... imagine 90+

[@vespass225]

@@jungtarcph Or even 100+!

[@1rewd133]

Yes! I've been wanting this for a long time. Very well done. Thank you!

[@PearlAcoustics]

Thanks

[@666chew]

Thank you for making this understandable to a layman such as myself. There's too much erroneous information out there on various sites and blogs and this clears things up quite nicely. I'm presently interested in a 87db monitor and have a very fast 70 watt integrated (GaN FET) so this may just work out nicely for me.

[@PearlAcoustics]

Thank you very kind.

[@thomasedward2231]

This really awesome. Thank you for this.

[@charlesmiller6281]

If the first watt isn't any good, why would you want 200 more of them?

[@sc0or]

Because "old good" recordings assume you have to have enough in a reserve to play all peaks. Because typically 200W amplifier will have less distortions at 1W than a 10W amplifier, as well as 200W speaker comparing to 10W one. Because 200W woofers are simply bigger than 10W, and so have massive, volume, alive bass.

[@hauxon]

​@@sc0orWell distortion is not all equal. Our brain likes second order harmonics better than odd order harmonics so a 10W tube amp at 1% distortion may still be producing a pleasant sound to our ears. A have an 8W 300B amp at home (and 91db speakers) that sounds terrific ..on violins, acoustic guitar, piano, vocals you can play loud. And for moderate volumes it sounds great for anything you throw at it. But as expected it looses breath playing bass heavy material loud. Put Mother on from Pink Floyds The Wall and it will play loud until at 2:50 where the drums kick in. Lower the volume to moderate listening levels and those 8 flea watts deliver.

[@effenrad6776]

New to channel. Really liked the explanation for home audio and how loud one watt is. Efficiency of amplifier as well. I’m a car audio guy that uses 20,000 times it in my car just for bass. Wow. I’ll be watching more

[@PearlAcoustics]

Thank you

[@MichaelYates]

Thanks for this excellent demonstration

[@chris-non-voter]

My Tannoy Cheviots - I've owned them since 1976, are driven by a Leak stereo 20. 10W per channel. I have never used any where a quarter of that. I've never felt the need to up grade or change. They deliver everything I need - I love the sound I get. Thanks for another excellent video. 👍

[@PearlAcoustics]

Thanks for your kind appreciation Chris. Enjoy the Cheviots!

[@albylizhard]

Hello, just bumped on this comment.I have a Stereo Leak 30 plus, it's rated 15W amp per channel, but with any of my speaker It's loud enough to make people run away.Not that is what I want, just wondering why I usually need to get it more then half volume to have some beef out of my speakers. Maybe it's because it's not a tube amp? Can you explain this? Thank you very much

[@totalplonker824]

Thank you for the enlightenment! Because after watching quite a few videos of content providers demonstrating their speakers, i was always under the illusion that when one is watching/listening on KZbin, one is rarely unable to tell the difference between a average speaker and great speaker! The funny thing is you wasn't even demonstrating just how good you're beautiful sounding Sibelius are! Maybe it was the placement of those professional-looking mics, I really don't know, I'm new to this but what I do know is those speakers sound wonderful!!! Thank you changing my perception of just how good speakers are able to sound even going through KZbin. compression

[@phugoid]

Now that is one capital video! Well done, Sir. Thanks

[@PearlAcoustics]

Thank you, very kind!

[@pf5658]

Wow! The sound really came through well on KZbin. Sounds fantastic.😊

[@PearlAcoustics]

Thanks!

[@scaryperson27]

Nicely done video!

[@obscurazone]

This was so SO good! V informative and enjoyable :)

[@blackbeansmatter1280]

Wow that was very informative and helpful. Thanks so much and it sounded amazing.

[@PearlAcoustics]

Thank you. You’re very welcome

[@diegogarces6931]

What a superb video. Thank you

[@PearlAcoustics]

Thanks Diego, glad you enjoyed it.

[@rodrigocastillo872]

Nice job, thank you for this video

[@joshuajones9482]

Ok my mind has been blown by this video.

[@mochipepper]

I've been looking for a demonstration like this for long time. Now I get the picture of what 1 watt sounds like. I have to now question the need for 200 watt speakers. Thank you.

[@PearlAcoustics]

Dear Raymond, unless you have a massive room and want to play music very loud, you don’t ‘need’ 200W loudspeakers. But there is no connection with enjoyment. Ie (using a car analogy, having a 5 litre Aston Martin can be fun, even if you are only driving at normal speeds. Enjoy your music

[@rosandpl]

bear in mind that it is 1 watt avarage, while sinus with bas peak is higher

[@TheCharlesAtoz]

I really enjoy Harley's audio symposiums-- it would be fun to meet him as well.

[@PearlAcoustics]

Thank you. The best way to meet him is at a European HiFi show, or by appointment in Belgium

[@davej3487]

Great explanation. Many years ago I picked up a Amp from an estate sale of a well known 60's Rocker in Seattle when he passed. It was a studio Phase Linear D-500 with 550 Watts RMS at 0.1 THD. I have never gotten it above 10 watts as there is no need. Really just 3 watts is enough for most LP's. Playing Chicago Transit Authority's California Purples it's stellar.

[@PearlAcoustics]

Nice story, thanks for sharing

[@TheAlphaAudio]

Brilliant. Very well explained!

[@PearlAcoustics]

Thank you.

[@2574mcu]

Great video.

[@adunacamilo9863]

Great demo

[@PearlAcoustics]

Thank you

[@boydsargeant7496]

Nice demo!

[@PearlAcoustics]

Thanks!

[@TalkCafe]

Great explanation, thanks!

[@PearlAcoustics]

Thanks!

[@gerrit555]

Thank you for the demo and all the other infos in the other videos. It‘s helpful for me to buy the right new stuff....

[@PearlAcoustics]

You’re very welcome!

[@gerrit555]

@@PearlAcoustics Du you have dealers in switzerland where I can hear „the“ Sibelius? I like the idea and the style very much and the speaker would have a really good size for my needs and room...

[@PearlAcoustics]

@@gerrit555 thanks fir your kind words. can you contact us via our website and we will help you from there... PearlAcoustics.com thanks!

[@bigjay1970]

That sir was genius and well put together! New sub!🤗😉😇

[@johndurak]

Thank you. Proof of quality, over quantity.

[@methedutch9647]

Great experiment, thank you for this ear opener!

[@Harley1Lovegrove]

You're very welcome Henk!

[@kimbiwasmith9661]

I hope YOU enjoyed the demo, because I've been playing guitar in front of amps that loud or louder fir years and though it FEELS great to play through a cooking amp, it will certainly wear you out. It was a cool demo. I already knew the conclusion from practicing at home. Five watts will piss off the neighbors,much less eight or more. I attenuated of my amps at home, which are 14 and 15 watts respectively. Occasionally, when neighbors are gone I will plug in and play in wet'dry or duel mono/ stereo. It is DEVINE, but brutally loud.

[@PearlAcoustics]

😉 indeed, I had a lot of fun.

[@James-ce7wo]

When his 2 watts is louder than your 500.

[@ilpatongi]

Well I guess that's what happens when you buy "500" watts speakers.

[@automachinehead]

Just look how big those tubes are. I have an 89db/w fostex speakers here hooked to a 22kg Yamaha ss integrated rated at 130w rms into 8ohms that takes in 600w of input power and a 98db pro jbl speakers powered by a 1kw class D amp. The Yammies have beefier bass and meatier mids than the larger speakers and I believe it's because of the toshiba output drive transistors and the two very large filter caps in it that makes the whole class ab much preferable to audio than class d for low levels. But the pro speakers of course would destroy any of these puny hifi speakers in regards to pure sound pressure level. I practically listen only to two genres at a time, old classical music recordings and 70's rock. JBL for the former and Fostex for the latter. No matter how good hifi is, pro audio beats it flat out in dynamics.

[@ilpatongi]

@@automachinehead I can't quite understand what you're trying to say. Dynamics and SPL aren't the same thing, and whilst of course a serious and expensive pro-audio setup would destroy any HiFi setup in terms of shear volume, I wouldn't necessarily claim the same regarding sound quality. Pro speakers and amps can sound very good, but that means you need to buy expensive equipment to achieve the same sound quality of something that you could have with much cheaper HiFi components. I'm not talking about records and tube amplifiers either, those aren't for "pure" sound quality.

[@James-ce7wo]

@@ilpatongi I mean for now a have a LG XBOOM stereo thing. But sometime in march I'm getting like a Sony DH something receiver, 3000w rockville amp, (2) RSG12s from rockville, and the RBG10 sub. plus all the necessary wires and stuff.

[@ilpatongi]

@@James-ce7wo I doubt you will solve anything if quality is your goal, it's extremely cheap and low quality stuff

[@mrboat580]

I connected my Pass DIY Class A, 8 watt amp, to my 98db speakers and it showed me quite quickly just how little power my speakers need. Half volume was enough to run people who don't like loud music out of the house and at 87db at my MLP barely had the volume cracked. The 25W Pass diy F5, is an absolute monster in that role. I think the giant caps in the power supply must help as well.

[@antreaskonstantinou8585]

I was thinking of buying 2 99db woofers and powering each with 250 watts but your comment might have changed my mind😂

[@summerforever6736]

Well done! Nice music!

[@PearlAcoustics]

Thanks!

[@fabieneldridge3414]

Sounds Great ! Your the Man ! Nice speakers and amp ! I run very efficient speakers I think 101 db Klipsch k- Horns up front and Klipsch Belle’s in Back . I run A&B speakers because the sound of them blended is wonderful. The room is filled with music just wonderful.

[@PearlAcoustics]

So good to hear your passion coming through Fabien. Thanks for your kind words. Enjoy the music!

[@jackbarnard1781]

You know..i was just listening to one of my most favorite pieces of music. A fresh 2020 BBC recording of Vaughan Williams. A lark ascending. At one point it's only the strat & a triangle. I was just thinking how splendid your loudspeakers would resolve this. Cheers as always!!! 😀

[@PearlAcoustics]

Hi Jack. It’s very true… often big complex pieces can impress but, I, like you am mostly blown away by the simplest of moments. Getting that right in both the recording and the playback is so critical. But let’s not forget the musicians - these moments are so dammed difficult to pull off in a convincing way

[@anoxicfiltrationplenums]

Excellent video

[@PearlAcoustics]

Thank you very much!

[@stpd1957]

That's a highly informative video, Thank you. Seán

[@PearlAcoustics]

Thanks

[@justScrollin0627]

This is absolutely amazing and I had no idea....When I was a teenager I was very interested in car audio...with all the 500 watt 1000 watt amps all over the place and one day my father took me to a car audio store with him...It was an authorized "Kicker" dealer which is what my father was shopping for..In a really nice display they had their Amp selection and I noticed that many of them were labeled as "25 watt" or "40 watt" amplifiers and were priced fairly high..I asked the guy how could only "40 watts" be enough to do anything and he said "because they are real watts"...I never understood what he meant but now I guess this is what he meant...

[@PearlAcoustics]

Hi Gregory, Some manufacturers ‘cheat’ they talk about music power ie peak and not constant driven power or RMS. it can be a factor of 10 difference. Most OF THE hifi industry - go on RMS

[@justScrollin0627]

@@PearlAcoustics So is it true that a higher efficiency speaker takes less power to drive it..but in turn the lower frequency ranges suffer? Just trying to make sure I understand it correctly...Or is it possible to have a sub woofer with a high db efficiency rating (90-92 db) that produces good clean low frequencies (25hz - 80hz) ?

[@f430ferrari5]

@@justScrollin0627 yes it’s true that high efficiency speakers take less power to drive it but there is a trade off. My understanding is that low frequency doesn’t necessarily suffer. You just need a bigger size box/cabinet to produce your desired low frequency results. 87.5 db for a speaker isn’t high efficient. 90-92 is almost mid efficient to me. Anything above 92 is high efficient. What is a bit misleading about this vid is that low wattage Class A valve/tube amps work well with slightly more efficient speakers when playing “classical” music. While 87.5 db isn’t efficient this is more of a test as to how loud even 7 watts per channel can produce. The thing though is that doubling of wattage doesn’t equate to doubling of loudness. Not sure if the author made this clear or not. Perhaps he assumes most audiophiles know this. If one listens to bass heavy music then wattage from a reputable amp company starts to become much more important. There are always trade offs though. My listening presence is geared more towards hip hop pop rock jazz classical in that order. It’s perhaps this preference because my system is designed this way. I have Class A/B amps and cone type speakers with a subwoofer. I’m running 1,200 watts RMS of true clean power. 5.1 system. 200x5 plus 200w sub. My system does not sound as musical as this KZbin vids system.

[@Scott31415]

The speaker sensitivity tells you how loud they will be at a given input power measured at a given distance. I this case 1W @ 1 meter will produce a SPL (Sound Pressure Level) of 87dB. To double the volume level (SPL) would required 3dB, or 90dB for this speaker and twice the input power, or 2W. 1W @ 1M == 87dB 2W @ 1M == 90dB 4W @ 1M == 93dB 8W @ 1M == 96dB 16W @ 1M == 99dB SPL falls off at a rate of 1/d^2, or 6dB at 2M. 1W @ 2M == 81dB so to get 99dB @ 2M with 87dB sensitivity speakers would take 64W of power. Of course all these numbers are based on a single speaker. Multiple speakers at the input power will create a louder soundstage. Just in case you were curious about the numbers. :-)

[@henrikl1394]

Completly right, I was just thinking write this to. Becaus e he said 8 w would be enough for 100 dB , but so isn't the case. Then the speaker isn't static 4 or 8 Ohm, that very to. And some speaker's are very hard to drive. For that you maybe need some umph in the Amp.

[@PearlAcoustics]

@@henrikl1394 thanks for your input. However, if you noticed, I had two speakers driving into the room (left and right channel) and that gives an extra 3db. Thus: 90db at 1 watt per channel and therefore 99db at 8 Watts. The sound pressure level meter recorded over 100 dB in my seating position, and that’s all that counts at the end of the day? I only wanted to show how loud 1 watt per channel can be in a domestic situation. I hope I achieved that. In practice I like to use amplifiers of at least 16w per channel.

[@asdfghjkl1755]

87db is 1m from a single speaker at 1W of power with 1Khz sinewave, not music and it makes signifficant difference. The fact that host is talking all the time makes db meter measurements invalid. At 1.6V we see +6db on the meter, which is 96db I imagine 2-3meters from the source, so something is clearly not right.

[@PearlAcoustics]

@@asdfghjkl1755 thanks for your input. I noticed that too and later discovered that in editing the sound pressure level meter image is not in sync with the the stereo mic soundtrack. This is noticeable at the end when the needle is no longer moving. But the measurements are correct in themselves

[@asdfghjkl1755]

​@@PearlAcoustics Thank you for response and congratulation on making valuable youtube content.

[@AdaptivePhenix]

Hey this is great 👍👍😎 I have a zillion questions but here is not the ideal place so let the research commence...subbed, BTW 👍

[@emiel333]

Great video and well explained.

[@PearlAcoustics]

Thank you!

[@emiel333]

@@PearlAcoustics You’re welcome!

[@tee-jaythestereo-bargainph2120]

Awesome Video !!!

[@picobyte]

I do agree 1W can get pretty loud, your multimeter is just not the right tool here.

[@oysteinsoreide4323]

Yes, you need a very fast voltmeter for this.

[@samohraje2433]

Or osciloscope. Measuring the voltage using volt meter is inaccurate. And the second inaccurate measure is the song he plays. When you need to measure how many dB your speakers actually producing , there must to be a sinewave signal with the same frequency for example 1kHz test tone or 5kHz test tone. Speaker coil is not exactly a resistive load when AC voltage is applied. Since the voicecoil is the coil not a resistor , when you apply different and changing frequencies , the actuall resistance is changing too. Expensive speakers have datasheet with them or , use induction meter to measure inductance not the resistance because it is not the same resistance

[@oysteinsoreide4323]

@@samohraje2433 Yes, osciloscope is much better. And having a controlled sweep or sine wave is better. He probably doesn't realize that music has peaks that goes much higher than RMS. And also the dynamics in the music can have several times the average energy. So his way of measuring things very flawed.

[@samohraje2433]

@@oysteinsoreide4323 Sorry i forget to mention , it's not a inductance , yes , coils have inductance but to be right , it is impedance. Impedance is much more complex to measure right values than resistence.

[@dhruvmeena96]

its a Transmission Line speaker and the impedance peak due inductance behaviour of voice coil would be flattened out, so it would be a pretty flat impedance load to amp i think, just some high frequency data reading would be off, otherwise it would be pretty much a linear drive

[@kesm66]

I have a ‘low watt’ desk top set up. I have an amp switcher that allows me to run a Schiit Aegir (20 watts into 8 ohms) or the LTA MZ3 (1 watt) paired to Omega Super 3 High Output Speakers (97 db efficiency; 6 ohms impedance). It is amazing! Note: I love the design/decor of your room.

[@PearlAcoustics]

Thanks! I suppose I can guess your LTA MZ3 drives your Omega’s just fine, or do you crave that ‘extra watt?’

[@kesm66]

@@PearlAcoustics The LTA drives ‘em just fine; I have the Aegir in play primarily during the day for a more visceral response. I typically use the LTA MZ3 at night...as it has a soft/lush sound quality/nuance. I love having both options...but honestly...I’m stunned by what 1 quality watt can produce. I have the LTA MZ3 serving in full capacity as a amp/preamp/HP amp. So the Aegir is my primary amp in my desk top set up...I run the LTA MZ3 as an amp option. Either unit can drive the Omega’s beautifully. Note: I have a main rig as well which is comprised of a 200 watt into 8 ohms Krell Vanguard integrated amp paired with Salk Song3 Encore tower speakers. I fully understand what a larger system provides. Having a low watt desk top system is simply a different (not necessarily better) experience (more intimate). I listen to the desk top rig daily as opposed to the main rig (preference).

[@skitstorm5634]

I’m thinking of buying the Schiit Aegir but not sure how good it will work with my speakers - AudioVector QR1. I’m a complete rookie when it comes to this. Any advice is appreciated and highly sought after. The QR1 are 4 Ohms, 45-45 frequency response, gold leaf upper limit (not sure what that is) 195 kHz and a 150 W power Handling.

[@kesm66]

@@skitstorm5634 I won’t pretend to know the answer. I’ve since sold off the Omegas and have the Spendor Classic 4/5 in line….which are less efficient than the Omegas…but I prefer the sound quality of the Spendors…go figure? The speakers you’ve referenced sound power hungry on paper at 4 ohms. I dare not say 1 watt will work. Have you contacted the manufacturer for amp guidance? Ex. Amp power pairing requirements and recommendations?

[@jjjpetersen]

OMG, I just learned a lot! Thanks :))

[@PearlAcoustics]

You’re very welcome!

[@Clint_the_Audio-Photo_Guy]

Great illustration! That said, I have 1200 watt monoblocks on my stereo, lol. I have seen about 120 watt peaks on the meters though, about 60 watts RMS and that's about all my ears want to take in the room. The speaker is a 87.7 db sensitivity Revel Ultima Studio 2. I will say the power demands increase hugely with the speaker's ability to produce deep bass. Also, to increase the volume 3db, you have to double the power, so it happens fast. The dynamics are actually audibly better than with the 600 watt monoblocks even though I'm only using 60 watts or less most of the time.

[@klm_]

You should go with 2400watts, sounds even better x') ..

[@ThanhLe-qo8cn]

@@klm_ Then you need air conditioning running when playing music.

[@joeysarmiento1925]

I don't have the test equipment you have but I get what you are trying to drive at. When I put my woofer and tweeter in a bigger baffle similar to what you have if not close to your Sibelius baffle dimension, it played loudly with the same quality. When I removed the crossover and wired it directly and played even loudly and that was the time we have to tweak the inside of the baffle and that's where my fun is. Mind you, when I was getting to a similar sound quality using a bigger baffle compared to the mini-monitor baffle I started with, I just trusted my ears. A few of my friends who are into the same hobby agreed with me. I am not saying I did a better job. No. You are Sibelius and since there are no Sibelius in my country, Philippines, I did the next best thing which is improvised. Congratulations on your Pearl Acoustics and I will watch your other equally exciting videos. Thank you for sharing and I am learning as I go along watching you.

[@PearlAcoustics]

Interesting thank you 🙏

[@joeysarmiento1925]

@@PearlAcoustics I have a Coral 12TX speakers with a sensitivity of 103dB owned by my olds and discovered it last year in our pile of 'To Go.' The Coral makes my solid state STR151A sound a bit like tube, a faux realization. This is where I compare the baffless 😉 I built using the two drivers from a mini monitor speakers. It also has several ports that I will experiment on soon made possible by my good carpenter. Again, your Sibelius is my dream 🔊 speakers. Thank you ☺️ for appreciating my narration.

[@PearlAcoustics]

@@joeysarmiento1925 hey Joey, thanks for your comment - what a discovery! Enjoy the music, and who knows? Maybe one day you’ll own a pair!

[@jackbarnard1781]

Great video. & very informative. I understand that these speakers can handle 70w peak. That's loud!! I listen to a 50/50 split of classical & 70s british progressive rock w/ a smattering of late 50s jazz. I listen at low to medium volume. In fact I have vivaldis 4 seasons so it was easy to imagine these in my listening room. Not a stretch at all. I'm such a big fan of single driver loudspeakers. The simplicity of em. Cheers from California

[@PearlAcoustics]

Hi Jack. We have very similar tastes. Best wishes to California

[@jackbarnard1781]

Let me tell you...to spend an afternoon in your listening room would be a special treat for sure. W/ special music of course. Fanny mendelssohn piano trio yes tales of topographic oceans. Bruckners 8th. Camel mirage beethoven 9th alan parsons i robot bartok music for strings percussion & Celeste & pink floyd dark side of the moon. What a treat!!! 😀

[@PearlAcoustics]

@@jackbarnard1781 absolutely!!

[@DevonReviewer]

Excellent video, answered a lot of questions I had in terms of power and loudness.. what would you consider a reasonable dB level to enjoy hifi at? I.e. getting the best out of the equipment, preserving your hearing and not being a fatiguing experience?

[@PearlAcoustics]

Generally, in a small to medium sized living room... 86 dB is a good average to max level for most music, with mini peaks at 90db

[@salvadorrodenas3071]

@@PearlAcoustics and that is even too loud, I have enough with 70dB and in a concert live listening a jazz trio with vocals, I measure 80dB from a five row seat. Plenty.

[@TheCogitech]

Listening fatigue has more to do with harmonic distortion (more specifically, odd harmonic distortion) and/or unnatural frequency response, than SPL. "Loud and clean" will not produce fatigue as quickly as moderate SPL with 3rd order harmonics and/or a preponderance of midrange "shout". Having said this, I agree with the other commenters - somewhere in the range of 70-86dB is plenty. At 86 dB, no conversation is happening in the room without yelling.

[@ingenfestbrems]

The speaker cabinet’s doing the work

[@RobertChampion1]

Excellent video! I have a pair of Spendor SP2/3E speakers with an efficiency of 88dB and a lovely vintage Revox A740 amp, rated at 100 watts per channel. Apart from excellent sound, the best feature of the amp is a pair of very accurate power meters. My normal listening range is 1 to 5 watts. If it gets to 10 watts, I'm getting up and turning the volume down! Do I need 100 watts per channel? Clearly not. But as Harley explains the key feature of a great amplifer is the ability to respond to driver loads quickly and accurately. The Revox weighs 20kg/44 lbs, has a 1000 watt transformer and 4 15,000 mf electrolytic capacitors the size of beer cans. Checks all the boxes for me! Thank you Harley!

[@PearlAcoustics]

You’re very welcome! Enjoy the music!

[@kaymanul]

In just the right set-up, in a normal room, about 6 feet from the speakers, with 5W you should get around 95 dB peaks. That's plenty loud. For me, at least. But, in a larger room, further away from the speakers, just like that you need 50W. Because that's how things work. And if, for some reason, you so desire to peak above those 95 dB, let's say 10 more, have a wild guess. You need 500W. Level would be pretty loud. But there is another problem, especially with poor solid state amps. If the rated power would be 50 and gets driven at 50, there will be some sort of compression that makes music sound worse and worse (unless you have a very good amp, you need extra power available, even if not used). As someone tested this quite a bit, that's when the amplifier is also most likely to damage the speakers. Thus, there are some scenarios that would explain the need for power in a very honest way.

[@ziofanale3853]

It's about the 10th time I watch this video. As soon I'll be able to get a pair of Sibelius, they'll be mine!

[@PearlAcoustics]

That’s very kind. We look forward to making you a pair one day...

[@kasperkjrsgaard1447]

I remember that back in them days,,,,, I had an Audio Innovations Series 500 with a max output of 10 watts and a pair of Horning A1 Concrete horns with a Lowther P6c as far as i remember. It was so easy driven that the attenuator should barely be moved before it was extremely loud. Plus it was so dynamic that it was scary. I should have kept those speakers but at that time i moved a lot and with two loudspeakers at 150 kg each and a size of a big suitcase 105 by 105 and 30 cm depth they just got to go.

[@OscarSanchez-tk3hx]

Bravo I barely use 2 watts on my Klipsch speakers nice video thank you Sir.

[@davidsagarra9841]

Klipsch speakers are known for being highly efficient (just like other horn speakers); I own three pairs and the largest ones (RP-280F) can deliver 98dB@1watt, they sound HUGE!!

[@OscarSanchez-tk3hx]

@@davidsagarra9841 thanks bro good choice I love my Rp 8000 klipsch amazing sound clarity and details with any kind of music Kuddos

[@mcplutt]

@@davidsagarra9841 I just bought a pair of RP-280F. I think they will be great on my Cayin tube amp.

[@davidsagarra9841]

@@mcplutt Well done, the Cayin amp is more than enough for those highly efficient speakers. I have mine paired with a PrimaLuna EVO400 powermap. The soundstage is huge and the acoustic image is beautiful.

[@pimianimavdo1523]

Music is about dynamics and timing, silences and emotions included. :) Its also about micro-dynamics and harmonics and providing access to a moment in time. Its not just about watts or simply spl ratings alone (although well applied science is key to getting "musical great sound" in any playback setup and its indeed quite complex). . . From my experience, power ratings are not that important if all is is not well designed. I have done systems that worked very well with relatively low power amps and modest spl ratings and also experimented with 3 to 10 kilowatts per channel (using active x-overs and multi amp & driver setups) with superb results. . . Having said this, even if one could run into rabbit hole about the details and argument presented here, fact is i liked this video for placing a relative perspective on what one can expect with even average spl rated loudspeakers in a nice listening environment with a dynamic amp. Nice. :)

[@PearlAcoustics]

Thank you!

[@pimianimavdo1523]

@@PearlAcoustics -- I suspect we would have enjoyed a good conversation or two when I was working in Audio (a lifetime ago) between some great music listening sessions. Cheers! (& keep the good work) :)

[@PearlAcoustics]

@@pimianimavdo1523 I am sure we would have!

[@tigertiger1699]

Most excellent.....

[@nc3419]

I just ordered a small class AB integrated that produces less than 50 watts at low distortion (according to one review, about 33 into 8ohms and 58 into 4). Comparatively, I have a Hegel h160 (overkill for my speakers) which weighs over 40 lbs and plays very, very well on the speakers I listen to...bliss. Thought about class D but the amps I was interested in are just that, amps and I wasn't prepared to just buy a pre if I found an amp to my liking. Looking for a good dac with good pre abilities I can live with for a long time but I do like integrated amps. Regardless, a smaller, lighter footprint is what I am after. The amp I bought is a KECES E-40 and I am wondering how close to the Hegel it will sound at the volume I listen to which likely is typically a few watts as the video shows. I really like my amp but I have fairly efficient standmounts and as I get older, I don't want heavy. Looked at various tube, A/AB as well as class D choices and see anywhere from 35 to over 50 lbs (except class D). As I only listen at low to moderate volumes, I am hoping for a lighter, smaller solution that gives me what I need...within a price point I can live with which is under $2000, preferably well under. Did I once listen at 100 watt levels, yes. From time to time I may still want to do that but only a few songs and for a few minutes. So that may justify getting into headphones which is the next foray. But mainly I like two channel traditional speakers. Its been a long and both enjoyable and frustrating road trying to chose equipment over the years but at the end of it all, regardless of the equipment I have had, I just enjoy the music. Love the one you're with.

[@jimgroce9487]

Years ago I switched to a 2.3WPC amp and speakers with about 95 sensitivity, and have never looked back.

[@paulf.5261]

Thanks, great demo and explanation 😁👍 Now I’ve just got to see if you’ve got a simple explanation between 8ohm and 4ohm speakers🤷‍♂️😬

[@Steven---]

Nice video. I showed a friend something similar. that a T-Amp and Klipsch speakers could get fairly loud.

[@PearlAcoustics]

Thanks!

[@thiagobartolo]

Are there objective measures for comparing this dynamic capabilities between different amplifiers?

[@Odyss2023]

Often single chip very low power mini amps like LM386, LM380, TDA2822 are built with minimum parts of low quality, but if you use high quality capacitors and resistors with proper circuit layout, powered by clean DC power source like 12v battery, and matched with highly efficient speakers, they sound quite fine while using less than 1w of DC power(for example 12v 70ma). Of course they don't have the true HIFI specs, but I personally checked that they can easily produce average of 75~77db undistorted sound with one bookshelf speaker(8 ohm 2 way 5 inch 90db SPL) one meter away, while playing ordinary random musics, using less than 1w of DC power. Usually if there is a problem it's the low output music source and if you use a low noise device with headphone output and volume control it's fine.

[@braydencooper2441]

Even though this isn't too scientific, it is just a rough indication. It is super cool to see that power doesn't matter. Sensitivity does.

[@PearlAcoustics]

Thank you.

[@88dugjt]

Would love to see the same test done using a sine wave instead of a dynamic track. I'd bet you would need a less "volume" to reach that 1w/2.75v. Testing car audio I know it's impossible to get clamped wattage rating using anything with any kind of quick frequency change and especially so with lower end multimeters.

[@tomkohman4620]

Interesting demonstration. Is my understanding correct that the relationship between speaker efficiency, power and volume is highly dependent on frequency?. Most of the efficiency ratings I've seen are at 1000 Hz. How much power is needed to get 87.5 db at 500 Hz, 250, 125 or 62.5Hz?. Perhaps not an issue for the reproduction of classical music but a real consideration when selecting an amplifier for jazz or rock music with more low frequency content.

[@marran8140]

I love this video. My home theater consists of 7 Klipsch speakers with sensitivity ratings of nearly 100dB 1w/1m. I know my receiver is barely idling even at very high volumes.

[@PearlAcoustics]

Thanks. Indeed you could run your set up with a Decware Zen amplifier and still have power left over! 😉👍

[@marran8140]

@@PearlAcoustics I actually used an AA battery powered Sonic Impact T-amp for quite a while when I had a 2 channel setup with Klipsch forte II speakers. People who listened to it couldn’t believe that a few AA batteries could make them play so loud and clear!

[@PearlAcoustics]

@@marran8140 😀

[@VEC7ORlt]

You got me till the part 'amp needs to be fast enough' and the whole digicam equivalent - any and all somewhat adequate amps are way way faster than any speakers out there.

[@meckarmickebjornsson2567]

God demonstration 😍👍🏻👍🏻

[@PearlAcoustics]

Thank you 🙏

[@T1k3mys0n]

I just noticed about real watt output from amp to speaker the other day because I was curious and bought a multimeter, I was so surprised that my amp was only outputting like 0.2 watt with the usual volume I'm comfortable with, but my amp drew like 4 watt of power out of wall socket, I bought a watt meter for that. So watt to speaker is not the same as watt from the wall socket. And even 0.2 watt is quite loud.

[@Odyss2023]

Most audiophiles never built or heard of a LM386 one chip 1w bread board(or strip board) amplifier. A decent LM386n-4 amplifier circuit + 9v battery(or 9~12v clean DC power source) + efficient 90+ SPL bookshelf speaker combination will blow your mind. If you measure the DC current with DC current meter while playing music, it rarely goes near 1w.

[@PearlAcoustics]

Interesting! Thanks for sharing

[@Unker_Spunkanathan]

Just what I've been wondering recently. I revisited hifi during this covid season due to having more time at home and started visiting Internet forums again. I see people raving about 200W or 500W icepower modules and how cheaply they can built an audiophile grade amp with them. Started wondering... Do we really need 200W? I had a 3.5W 2A3 amp for a couple of years and I don't think I pushed it even halfway. Anything more and I would have been kicked out of my neighbourhood. So do we need that much power or 30W amp with a hefty power supply would meet most of our needs? Thanks for this video... It clarified all my doubts

[@startkapital]

often budget or just plain hifi grad equipement is not that efficient icepower moduels Purifi 1ET400A and hypex also TPA3255 with the Texas Instrument Chipset all offer very low signal to noise ratio almost silent even on higher loads these DIY solutions outperform many expensive Class AB also in terms of Money/ Value since a TPA3255 balance amp board and digital switching power supply is had for around 150 USD I transitioned my self from pure clas A to a class D and i am blow away by the performance

[@BlueCliff72]

I'm fairly new to high-end audio and have had a Decware SE84UFO2 on backorder for a while now. I've recently become pretty curious about the Sibelius! The Decware outputs 2.3 watts, which is concerning for 87 db sensitivity, but I rarely listen to anything at over 70 db loud, let alone something like 80 db. Would I really have enough power on tap for my needs here? Or do you think I'd be lacking a bit of control and not getting much out the speakers with this amp? I'd also want to avoid damaging either of the components, of course

[@PearlAcoustics]

Hi, very sorry for the late reply. If you listen as quiet as you say, you won’t have any problem at all. It’s a fantastic combination in the right room. Feel free to reach out to us via our website and we’ll be happy to advise you. We have customers with the same combination and we loved it when we auditioned the zen

[@jptok]

Thanks Harley for a explaining this topic well. I am using the small SMSL VMV A1 amp that you recently reviewed. It only has 10w into 8ohms and I am using it to drive the KLH model 5 speakers. Do you think this small amp is fast and good enough to bring the true potential and capabilities of my speaker?

[@PearlAcoustics]

Hi. Your KLH5's are quite effieicent +/- 90db at 1 Watt. I am absolutely sure that in a medium sized room 6m X 5m it should provide plenty of punch. At 1 Watt per channel you have 93db in your room! so at 8Watss per channel you wil have 101db - enough to do serious hearing damage. No dobts it should be bringing out the best in your speakers. But these things are all about synegy and your room acoustics, and personal taste too. Best wishes. H.

[@coyoteproject999]

that's why I LOVE my Klipsch with it's 98dB !!!

[@pabloosvaldopenizzotto1098]

Anyway I do agree that music stage is fantastic!!

[@brianhowe2078]

GREAT VIDEO. Very interesting topic. I wonder how much louder it would have been if you had your mic volume adjusted properly. Probably would have been too loud to listen to.

[@PearlAcoustics]

Thanks.

[@mvsrpharma]

Thank you

[@thor7564]

Good video for those who bash 3-8 w tube amps as underpowered. Add in that vintage speakers usually had 93-95 db sensitivity. 95 db is loud! For those who address bass: usually nothing under 40 hz on records, and definitly not under 40 hz on a rock concert. Why? Well, mainly because of feedback. So: has tech moved forward at all?

[@PearlAcoustics]

Thanks for your contribution to the discussion!

[@tigerstyle484]

There is a rule, +10dB x 10 watt. So a 87dB Loudspeaker would need 10 watt to be 97dB loud, 100 watt to be 107dB loud, 1000 watt to be 117dB loud and so on. But, the sensivity was measured at 1kHz (1watt / 1m at 1kHz). So, if you play music (variable load and frequency), especially with a lot of bass, you will need a bit more watt to reach the 87dB.

[@brucegelman5582]

He said 8 watt amps drove his speakers to over 100db so how does your formula make sense.Please explain.

[@tigerstyle484]

@@brucegelman5582Dude, i've explained it in my answer. What exactly you don't understand?

[@EricLee-rz2vo]

Is it right that always taking tube amplifier instead of transistor amplifier in terms of sudden current flow (another saying of power)?

[@georgecromar4094]

Great video and demonstration. How does one quantify the dynamics of an amp?

[@PearlAcoustics]

Thanks George! Much appreciated

[@mathmathematics4420]

So, speed of amplification is directly proportional to the loudness no matter what type of speaker and materials used in them are. Is that your point? This video is interesting because I have never reached that level even with way more power. Even though I have used a lot of amps both vintage and modern ones. Also I'm just curious how much of RMS can those drivers handle.

[@512bb]

It's kinda of like the young car guy these days obsessed with big HP figures but it's torque that's king on the street.

[@PearlAcoustics]

Very good point! Thanks for adding to the conversation. I should have thought of that analogy 😀

[@paulcampise3050]

Definitely subscribed after your informative presentation, looking forward to the next. The music drowned you out at the close, unfortunate because I wanted to hear all of your close.

[@wattspeakers]

That sure sounds a lot louder than 1 or 2 watts.

[@danielgeiger7739]

Interesting demo, even if one may quibble about technicalities. Two questions: - What is the typical relationship of volume level set on amp to proportion/% of power used? I have a 120 W/channel amp, usually turn knob to about level 35/100 for less than speaking volume (~50-60 dB) in room with 88 db efficiency speakers. Knob turn would suggest ~35/120 W =~40 W going to speakers, but your demo suggest more like 0.1-0.2 W. Hmmm. - Linearity of amplification was recently discussed by Ask Paul, who argues that strict linearity only exists in about bottom 10% of amp range. Does that linearity range differ with amplifier type (A, A/B, D)? That would explain why Nelson Pass First Watt amps go at max to 30 W (class A if I recall correctly), but your class D mono blocks have 600 W of potential power.

[@TimpBizkit]

A volume control is usually scaled more on perceived loudness than power. Usually at around 5/10, the amplifier is 10dB below maximum - "half volume" is only about 10% power. At "35% volume" you will be using 3.6 watts out of 120, but the input gain is also important, as is the scale on your volume control for instance half the clicks on a scale could be 20dB down, and if the device uses the decibel scale, it could be a tiny fraction of maximum. If the input gain is higher, it could be more power, but the amp might clip at just over mid-way, or it could not reach maximum power at full volume if the input source is low. Also music doesn't stay at its maximum level all the time. Only the loudest part of a song will use the amplifier's full power. This explains why small speakers can handle amps with surprisingly high power ratings, because the speaker isn't subject to a continuous tone. On average, only 10-25% of the amplifier's maximum power stresses the speakers at maximum "clean" volume.