How to choose correct amplifier wattage

[@jeremiahchamberlin4499]

I know that when I attended my first electronics course at community college, the fact that devices drew as much current as they needed just blew my mind; it seemed as though I had just learned one of the secrets of the universe.

[@homeboi808]

1) Pick an SPL target, 100dB for instance. 2) Find speaker sensitivity (dB @ 1 meter away, hopefully anechoic and not in-room, Klipsch gives in-room). 3) Take into account room gain, usually +3dB for speakers with bass and +2dB for speakers with little bass. 4) Know that 2x wattage gives you +3dB and 10x wattage gives you +10dB. So, 100W gets you +20dB over the stated sensitivity. 5) Take into account distance. If you sit 10ft away, that’s about -6dB. So, if your bookshelf speakers are 84dB @1W @1m anechoic and you sit 10ft away, that’s gonna need 100W to reach 100dB (84, + 2 for room gain, -6 for distance, +100 for wattage).

[@homeboi808]

@Taco The math was for a single speaker. 2 speakers obviously will be a bit more.

[@nikhilsuryawanshi6301]

@@homeboi808 absolutely .... Every woofer count in system .... +3 db boost If your woofer is rated 86 db @ 1 watt Asume MTM in LR sides ... 86+3+3+3 ---- 95 db ....real Asume TM in LR sides ... 86 + 3 .... 89db

[@sarmehdi]

Non-audiophile here, but I follow audio tech and reviews as I find them engaging. Before this video, I had never come across anyone - in-person or online - that explained current and power so succinctly as Paul did in under 8 minutes. Just fabulous!

[@Justwantahover]

I agree.

[@krismichalsky]

Paul definitely has a way with words no doubt.

[@AndyBHome]

I'm making a playlist called "The Best of Paul McGowan Explains Why More Is Better When It Comes to Amplifiers" - it will only be the top 100 videos of Paul answering this question.

[@manj2482]

Definitely buying ps audio when i got my money right. Passion inspires, informs, and sells.

[@robertkeefer7791]

It's all about having adequate headroom for the amplifier to provide for sudden increase of Volume to transient parts of music instantly.

[@FraktaleFatalitaet]

It really like to know some numbers for once. Do I need a 100W amp for normal listening volumes on a 100db/1m/1W speaker? I dont think so, but what are the facts.

[@sMASHsound]

that IS a key advantage, but its not 'all' about that, the sudden increases in volume. but, that same capability, imo, helps it as it nears the limit of its range, where it isnt stressed to produce sound/signals if its a powerful amp, comapared to the same output of a less powerful amp.

[@My-Pal-Hal]

@@FraktaleFatalitaet Of course. It depends on how your speakers came about their rating. And the frequencies tested. Many say 100db. But rated at only 1000khz for that number. And in multi driver speakers. You can Gaurantee. This rating isn't reliable to say the least. As with a 3-way system. Only the mid-range speaker would even be producing 1000k. I've been an audio guy since the 70's. And have never seen a speaker produce a rating with anything but strict test equipment. (and not often) And Never in any real world applications. More is better. And Headroom extremely important in today's Home Theatre applications. And even amplifier ratings are spurious at best. RMS X 20-20,000hz X Distortion is the SPEC's you should look for as a start. Then determine how it was tested to achieve same. And you May find many amps, only rated at 1000khz. Imagine that 😂 ...jus my short opinion...

[@timharig]

No. There is more to it then that. The more of the amplifier's range that you use, the more non-linear it's output becomes. It is like seeing the curvature of the earth. The further away you get from the earth, the more you see of it and the more that you can detect it's curvature.

[@KenTeel]

@Taco You point to an interesting thing in this equation: speaker efficiency. If you're listening at a level where a sine wave would only go to 30% on each side of a sine wave (leaving 70% unused on each side), with a 100 watt amp, you're not running it into a nonlinear response. So, why would you need more wattage? Sometimes this stuff gets like guys bragging about the amount of horsepower in their car engines. Do you really need 600 horsepower in your car..... afterall, unless you're in an extreme circumstance, less horsepower will work just fine.

[@SPEEDOFDOG]

Thanks for explaining this. Been wondering for years. Always wanted to ask but didn’t want to get the looks of stupidity for not having known something since birth.

[@كورسسسكوللشبكات]

I have an Bose amplifier: 2x50w @4 ohms, 2x25w @8 ohms And Bose speakers: up to 80w, 4 ohms What's the maximum numbers that amplifier can handle?

[@stephenmead5488]

Optimal levels for gain staging are sometimes assumed to be -20dbfs (decibels full scale). This means that the normal listening level has roughly 20dBs of headroom to account for transient peaks. This is pretty reliable as a rule of thumb, especially for digital sources. Vinyl, not so much since things like record warp and needle drops can blow woofers connected to high power amplifiers. If a comfortable listening level for you with your current room/speaker/amplifier combination is 80dBs at the listening position, and this level can be obtained @ 1W/channel, a good rule of thumb would be to have a 100W/channel amplifier to provide 20dBs of headroom. Ironically, highly processed popular music could be accommodated with less power at the same or greater apparent loudness due to the significant compression impeding dynamic range, all things being equal.

[@srikanth04]

Hi Paul, I just hit you with a similar question last week from Arizona, Looking forward to see that video sometime in the future. But coming back to this video here, you explained it so well saying it wont make a difference for moderate listening levels however at the end you contradicted the whole explanation and asked to go "BIG" :) I still need more clarity , looking forward for more explanation ! Thanks for your great work ! very few ppl are are generous enough to give free wisdom !

[@Paulmcgowanpsaudio]

Well, yes, that can be confusing. It's hard to say the right thing and have everyone covered. There's just no getting around the issue of headroom. You cannot have too much which is why I say go big. But that said, it's not going to make that much difference at moderate listening levels - but that assumes you won't always be listening at moderate levels. I have a few tracks I listen to a medium level but they have several places where the dynamics are huge! I don't want to mess those up either. Bottom line, since we cannot know what your listening habits will be now or in the future, or what kind of music you're listening to, it's better if you have a choice to go big.

[@jeremiahchamberlin4499]

The situation with electronic sound amplification is that two things are going on at once; the amp is drawing power from the wall, but it is also making power for the speaker. Like an electric motor, the amp is kinda dumb, and the speaker is too, intelligence, and ‘protection’ must be added. When the source increases its dynamics (gets louder), the amplifier responds in kind and sends more voltage and current to the speaker to cause it to worker harder, push more air, and thus make more sound, in other words, to get louder too. So far so good. The volume knob has the same effect. We use the volume knob to adjust the loudness to our liking, what could go wrong? Two things. In response to the user’s request to play louder (using the volume button), the amp can be driven into clipping. If you are feeding a single test tone into the amp, the swings of voltage become so great that they can no longer be contained within the operating range of the output devices (transistors or tubes), but the amp will try anyway. On the oscilloscope, the tops and bottoms of the wave form will flat-top. If connected to a speaker, the user will start to hear the sound distort itself, because the signal it is receiving is distorted, but it will try to reproduce it anyway, because it doesn’t know any better. If this situation is allowed to continue, one of two things will happen depending on the ‘balance of power’ between the amp and the speakers. 1. ) If the amp is rated for, say 30 Watts, and the speakers are rated for 200 watts, the amp will blow. The amp will also blow if the speaker’s impedance is too low, as in hooking four 8 Ohm speakers up in parallel and thus presenting a 2 Ohm load to the amplifier, but we’re not talking car audio, here. 2. ) If the amp is rated at 300 Watts and the speaker is rated at 60 Watts, the amp won’t go into clipping, the wave forms won’t flat-top, but the speaker will try to exceed its mechanical limits of excursion, it will start to heat up from the extra current running through it, the voice coil will expand, start stick, get stuck, and the speaker will destroy itself, if that happens, it could take the amp down with it; hopefully it will blow a fuse on the output side of the amplifier before it does that. There are other ways that amps and speakers can damage each other and blow themselves up, like turning the bass tone control up so high the voice coil is slapping the magnet at the rear. And there are ways to add protection to the amp so that it recognizes when clipping is occurring, and notifies the user (who is still free to ignore the warning), fuses can be added to speakers is case there aren’t any in the amp, etc. So, while in the main, on this topic, Paul is correct to emphasize the desirability of equipping oneself with a powerful amp, and there are advantages to having one, when the whole chain is considered there are several facets of performance that must be aligned to get optimal performance from one’s system. Buying an integrated amplifier takes a lot of the guesswork (and cables) out of it.

[@vvcv__00]

I personally enjoy the sound of small watt amplifiers, both in Hi-Fi and instrument amplifiers. Not sure Fender could get the same sound, of their tweed amplifiers, in a 'high watt' version. Not to over simplify or generalize too much, but a lot of jazz guitar players, that have some fantastic sound, all use small watt amps. As far as speakers, i'd have to say I sway towards the enjoyment of high efficiency speakers. Matched with a nice small watt class a amp, it's a sound I do enjoy more than I did with a high watt b&w or sonus faber sound. Knowing the sound you want, for me, is the hard part.

[@krismichalsky]

So please don't take this as me busting your chops, but I wouldn't compare full spectrum audio amplifiers to guitar amplifiers. In a guitar amplifier you want the break up of the tubes to occur, to get that "warm tube" sound. In an audio amplifier, you don't want break up otherwise the music would sound distorted. Tubes distort in 2nd order harmonics which is the next octave, and this is pleasing to the ear. However in HiFi, too much tube break-up and you will hear it. Low wattage amps are much easier to drive into that break up area where guitar amps start to get that natural good sounding distortion and HiFi (at least to my ears) not so much. I agree with Paul on this one. I run very high wattage amps that are not run very hard, so as to avoid clipping and a tube preamp for that natural tube sound.

[@atxplus]

It's weird, I have a pair of kef LS50, the recommended range of matching amp is 25 to 100w into 8 ohms impedance. It's a low sensitivity speaker. I got a musical fidelity m2s amp. Which is rated at 72w into 8 ohms. Boy in my room, which is a medium size British bedroom size. I can't get the volume more than 35 percent of the total movement, until the sound is so painfully loud.

[@donalddeorio2237]

Most people don't get that, they see a power rating of 75 watts and and they freak out if their amp is 100 watts. The one occasion I blew up my tweeters was with a 30 watt / channel receiver. Later in my audio journey I had a pair of Dahlquist DQ20i and I had an Adcom gfa5500 amp and a Carver avr100 receiver. I disconnected the crossover jumpers and powered those speakers rated at 125 wpc with a 200 wpc amp and 150wpc receiver and they were amazing, clear clean sound great soundstage and imaging didn't blow the fuse for high frequency. That's my experience with power ratings

[@iblesbosuok]

In my experience, between 2×50W to 2×100W amplifier adequate for regular home hearing. Don't disturb your neighbour, please. Cheers from Indonesia

[@كورسسسكوللشبكات]

I have an Bose amplifier: 2x50w @4 ohms, 2x25w @8 ohms And Bose speakers: up to 80w, 4 ohms What's the maximum numbers that amplifier can handle?

[@كورسسسكوللشبكات]

@Taco which word?

[@atticusrussell1225]

@@كورسسسكوللشبكات pretty sure he means bose

[@David-dj5kb]

This reminds me of when the Dodge Challenger Hellcat came out, it has like 700hp and people kept saying “oh your gonna crash with that power” or “how can you even handle that amount of power” or even “that is WAYY too much power for the street”. And I always thought, well just because you have access to all that power doesn’t mean you have to use it. You tell the gas pedal how much power you want and it will give you that.

[@Enemji]

David Pastars - The problem has always been how easily you can control that power. If 50% of that power is available at idle, that means 350 hp just as you start driving. That might be too much for most people.

[@David-dj5kb]

Nikhil Gee Lol that’s not how it works. The car won’t be making 350hp from a slow stop light start. If it would you would be spinning out all the time.

[@Enemji]

David Pastars - “If” was the key clause that you missed reading.

[@David-dj5kb]

@@Enemji Ah I see :)

[@MrDac0964]

That may be true but my counter-argument is if you’re not gonna use all that hp (or watts) anyway or very often why even bother getting and paying for them in the first place?

[@richarddarr3381]

Plain English ...loudess level using 80db is same in 10 watts or 1000 watt equal 80 db before you move the volume level up, what change the sound stage developed the sound is relaxing or it idle

[@Taffy84]

My speakers are rated to handle up to 300w but my amp is only 80w per channel @8ohms. But I use them in nearfield listening position on my computer desk and never have the volume past 1/4 so for my needs 80w per channel is plenty.

[@carlosoliveira-rc2xt]

Volume at a quarter means nothing. As Paul mentioned in this video he will go into gain at a later date.

[@mjthrillergn]

I learnt so much from this! Was always chatting RMS output but this taught me something...

[@lohsuankhoon4422]

Well described and thank you for sharing Paul. Cheers!

[@dragonflyfab8982]

As I have gone up in speaker sensitivity, down in amp power while improving signal to noise. My sound has become magical! Sorry Paul, big amps are for big egos or football stadiums.

[@كورسسسكوللشبكات]

I have an Bose amplifier: 2x50w @4 ohms, 2x25w @8 ohms And Bose speakers: up to 80w, 4 ohms What's the maximum numbers that amplifier can handle?

[@drivethrou]

I bought Jbl L 300 Summit 1984. I didnt like them until i build my own 845SE amp in 1999. Now its perfect

[@donalddeorio2237]

The amplifier doesn't run at full output unless you turn the gain all the way up. Higher power is good for dynamics for brief periods of time usually milliseconds. Higher power also means your amplifier is less likely to be driven to clipping, clipping is what damages tweeters. I have a 5 channel power amp that puts out 125 watts all channels driven and the only times I came close to clipping was with movie. More power good. The only time I fried my tweeters was with a 30 watt receive.

[@soddi7239]

Amazing. I finally understand. THANK YOU!!!

[@jimbasler1054]

I find myself watching your videos,over and over. I don't understand all of the great info,that you give,but I hope if I watch them enough,some of the info will find it's way in my head. Thanks!!!

[@edgar9651]

Long time ago I had a 25W amplifier in my car. Then I bought a 200W (sinus) amp. Wow, what a difference. And I don't even talk about the maximum volume. Hearing music at relative low volume, a level which the 25W amp could easily do, the sound was a lot better with the bigger amp. Obviously the 200W could also produce a higher volume, but that was not the main difference.

[@Breakbrain1]

Tru, but not when you're kid (then 3 years old) is saying, nice music dad, while he turns the volume way up. And before I could tell him don't. The Smoke already was pouring out of the tweeters. And a year later, just when I repaired both speakers, my other son did the same. And I took a long long walk. Only one woofer survived. i Still love my kids. But never bought other speakers. Mabe someday, when they are living on their own I Wil.

[@captainwin6333]

Amps should have a max power setting you can set or a way to disable the front volume pot.

[@jkbrown5496]

It is possible to put more current through a coil, generating heat in the windings than a coil design cannot dissipate fast enough to prevent breakdown of the winding insulation, and thus smoke and shorted speaker coils. The question is why don't speakers have thermal fuses since coil design is independent of the power amplifier.

[@artderix803]

A Hegel H360 does that exactly. user can program minimum (start up) and maximal volume! ;-)

[@ohmythatsweird]

Two question to ask: 1. Are you speakers under warranty? 2. Are your kids under warranty?

[@ryacus]

@@captainwin6333 With all the technology we have these days an amp should be able have an input for specs of speaker and the amp can then adjust accordingly to the speaker hooked up.

[@DreidMusicalX]

Sounds much like my guitar amp. I like those big 100watt amps because they push the air and sound better. To me they have more headroom as well.

[@jkherberger]

Glad to see Mr Wizard found a new career.

[@BedPanAlley]

I suspect the misunderstandings and/or confusion stems from the association of the potential dangers of putting a lightbulb with a wattage rated higher than the lamp can support.

[@jeromemckenna7102]

My only worry with big amps is the ability of young children (we have grandchildren around on weekend), playing with the volume knob and blowing my speakers. It is amazing what kind of mischief children can get into.

[@crazymetallian]

welll i need more experience, lets say mu pioneer CS-A700... or klipsch fortes which are very sensible speakers to drive, and they might deliver the best with 5-10W RMS... i think a small 20W tube amp will drive them better

[@wesleyleigh4063]

Another concern is whether high wattage amps sound different to lower ones, or is the only reason some amps are lower wattage is to save on price of components. Like are you losing anything, say depth or resolution for picking a 750 watt amp compared to 50 watt one?

[@AllboroLCD]

"The Source Remains The Same".... That make a great title to a Paul book ; )

[@TheGwt3]

I never knew this about amps! I was always conscious of using an amp that didn’t exceed the max spec’d for the speaker. Thought it would overload it somehow.

[@TheTruthKiwi]

@Taco Yeah, and he should've said that if you crank the volume of a 700 watt amp with 100 watt speakers too high it will make you deaf AND blow your speakers.

[@DivergentDroid]

Thanks! I have to replace a door speaker in the used car I just bought. It has a 600 watt SPL FX2-600 amp. I had no idea if I needed to buy a 600 watt speaker set. I'm sure the door speaker is OEM. The previous owner added two Bazooka tube speakers to the back. I have no clue what they are rated for. I'm looking at a set of 300 watt speakers and hope I'm not making a bad choice.

[@CheeseForEverybody]

Hello there! I am trying to make sense of the whole amp - speaker - wattage issue and the more videos I watch, the more confused I get. In this video you are saying that you can't have too much wattage on an amplifier. But in a very similar video about amps and speakers you say that the wattage of the amp should NOT exceed the wattage of the speaker (which makes sense to me). Do you mean that you have to be careful and not pull up the volume control too much in order to keep the speakers safe? Sometimes people say this, sometimes people say that, I find it extremely confusing! Could you maybe enlighten me once again on this subject. Thank you very much, Cheers.

[@kamesh_98]

Hi @PSAudio , I'm first time building a speaker on my own. I have 100w 2.0 Apm that will power 50w/channel. for 3 way crossover i chosen: woofer - 40w mids - 15w tweeter - 15w all are 8ohms (i have option to go for 4ohms) What do you think, in total 60w for speakers is too much or how should i choose mids and tweeter power?

[@sonnyaraneta6488]

Big amplifiers don't make 1 set of speakers louder (even if your speakers has big wattage capacities to handle the push of the amplifier) add a multiple set of speakers in your big amplifier to accommodate the loudness that you need. Just make sure that your amplifier has 25% more power to the total wattage needed for multiple set of speakers.

[@howardskeivys4184]

I have an old Rega Elicit amp rated I think at around 105 watts. It drives my 88db efficient floorstanding speakers. I very rarely set the volume control past 12 O’clock. It would be far too loud, in excess of 105db! If I connect my preamp and 400watts monoblocks to the same speakers, turning the volume control to 12 O’clock only raises the SPL to around 78db after that the SPL rises sharply when turning the preamp volume higher!!

[@Drivehead103]

Still trying to figure it out. I am probably going to try to go with high power because I do like to crank it up now and then. I understand the Hi Power Amp not running out of as you increase the volume. But then I read about tube amps putting out 16 Watts that blow 100 watt amps out of the water. I also read that the first watt is the most important and that most of the time people do not use more than 5 Watts. I am wanting to go with a tube amp or maybe a hybrid. Thinking about a Vincent sv-237mk because I could later use it as a preamp and and a high power amp. Primaluna premium or dialog is looking tempting also. Also considering getting ohm 2000 speakers or maybe ohm 1000 since my room is only 15 by 15. Component matching is very critical and glad to see PS audio tackling that issue also.

[@nancy4don]

"Clipping" is a description of what the waveform of an overdriven signal looks like on an oscilloscope - it's like the tops of the waveforms got "clipped off." When that clipping gets really severe, the waveforms resemble squares - "square waves." When tube amps clip, they don't behave like a solid state amp. SS amps pushed to clipping put out lots of third harmonic distortion and even square waves, which are VERY damaging to speaker voice coils (and sound dreadful). Tube amps clip "softer," meaning the harmonic distortion is more musically related to the main sound. They also aren't as quick to generate square waves as a solid state amp. So even if you start pushing a tube amp to its limits, the onset of nastiness is more gradual.

[@johnsweda2999]

There's a thing "generally sounds better" it doesn't have to be the case. If you got 100 watt speakers you could easily blow them if you turn it up very loud. Nobody needs 900 Watts there is head room and there is head room... use in a home situation it's not necessary to have that power. you take the music fidelity A1 at 20 Watts it is a very good sounding amplifier in anybody's language can and will some better than a 300 watt amplifier

[@alanrcrews]

The potential problem is the teenagers when the parents aren't there...

[@hamidnia7242]

Alan Crews 😂😂😂😂😂😂

[@Drackleyrva]

I have a Marantz PM8006 integrated amp w/70 wpc and thinking of getting the S300 amp to increase the wattage. I can use the Marantz as a preamp. My Dynaudio S40s love power and the Marantz just doesn't seem to have the 'juice' to do it. I hope this will work. Any thoughts?

[@paulgolub6823]

Go for it. 30 day free listen.

[@bphilbac]

Thanks Paul. Great info.

[@kencohagen4967]

The more the better, right? Well, what are you trying to amplify? How big a space? What are your speakers rated at as far as power handling, i.e. heat, can they take? 700 watts? Damn man! 100 is more than I need. 700, with a smart hand at the volume knob that would be ok. Yup, Paul is right. You can't force energy i to a speaker, but if you try to turn them up too high, no matter what the power is behind that, it will destroy a speaker. My roomate blew out one of his speakers with an old gorilla amp that was rated at 100 watts. He fried the other side on my 30 watt amp. It didn't matter, he overdrive the tweeter and it's excursion was greater than the room it had available, mechanically slammed the voice coils against the back of the magnet, mechanically breaking them. As for the bigger amp question, the more power you have available that's clean, undistorted power, the more your speakers can handle until either they reach they're mechanical limits, i.e., running into the back of the magnet housing where the voice coil rides on the cylinder attached to the magnet, or the heat is too great for the windings of the voicecoil to handle, melting them.

[@russredfern167]

But those peaks are murder on speakers that can't handle much. I have pair sitting downstairs since one of those peaks blasted the woofer. They were rated at 75 rms 150 peak. Paul I can't count the number of speakers that I lost over the years running big amplifiers.

[@nikonman3971]

There’s a difference between small & large amps like you said the clipping and or distortion on a small amp you get to the distortion level sooner and a large and you have a lot more before the distortion so at normal listening levels you have more perfect Sale Lester no distortion

[@Justwantahover]

Some speakers like the Klipsch Heresys don't need much power and so a small amp won't clip till it's really loud. But still they can take a big amp too.

[@KenTeel]

Of course higher wattage amplifiers cost more, generally. So, if economy is important to you, ask yourself: how loud do I want to listen to my music? If you're not going to blast your music, then you won't really be using all that wattage potential in a higher wattage amp. You can get away with a smaller amp. Of course Paul's arguement would be (guessing) that having more headroom, with more postential wattage, makes for better transient response, and allows for less asymentrical distortion (you get a better linear response on both sides of a sine wave, with symetrical peaks, basically plus and negatives as mirror images.)

[@emonymph6911]

This was beautiful

[@mikemiller5960]

i havea pair of krix neuphonix made in australia they rate at 300 watts i use a rotel pre and emotiva power amp that delivers about 420 watts perfect

[@scotts7017]

Yes Paul keep answering these.

[@كورسسسكوللشبكات]

I have an Bose amplifier: 2x50w @4 ohms, 2x25w @8 ohms And Bose speakers: up to 80w, 4 ohms What's the maximum numbers that amplifier can handle?

[@Holdeenio]

Thanks Paul, very insightful. Please consider giving a thorough explanation of gain. 😊

[@timharig]

For a voltage amplifier: outputV = gain × inputV The only complication is that gain is frequently represented in dB, so you need to convert the gain into a factor for the above equation to work: gain = 10^(dB/20) That's all you need to know about gain for a voltage amplifier.

[@masterchef6694]

Should we exceed speaker manufacturers recommended amp power rating?

[@fourtyw.4779]

Awesome.You explain very well!

[@joelrunyan1608]

The heavy work the watts do? Is stopping the driver after they make it move. That's where the damage to speakers occurr...

[@thelowmein9143]

Is this video referring to guitar amps and speakers or for an amp for a stereo system? Because I was always told that if I plug an amp with 100 watts (for example) into a speaker cabinet with a rating of only 50 watts, it will likely damage both the amp and speaker, is that accurate?

[@timharig]

It refers to any audio amplifier. You have a tradeoff. If you amplifier is too small it can distort or clip when you attempt to drive too hard. Clipping can damage your speaker. If you get too large of an amplifier and turn the volume/gain all the way up, then you can overpower the speaker and damage it. Paul's advice assumes that you are responsible enough with the volume control not to overpower your speaker. If you can be that responsible, you will have better sound quality with a larger amplifier.

[@mikimike]

Paul does it again. Making something so simple so complicated.

[@gtrguyinaz]

It is more than amplifying wattage.. sealed Box speakers need high damping factor to control woofers..

[@davidm7824]

so when i turn up volume on my Denon AVR i am increasing the output of the preamp in it and not the power amp?

[@timharig]

Probably yes. It is generally easier to design the power amplifier with a constant gain and handle any volume control in the small signal.

[@roberthuttle]

I returned my Rotel 1585. Clipped often.

[@bayard1332]

I was thinking about this just earlier today, but from a different angle... which was how to match amplifier power to speaker sensitivity. Mine is more of a mass market consumer angle, as it blows to buy a bunch of stuff and get home and find out your 95 watt AVR can't drive your 86 db speakers worth a damn... I just think the audio industry should make an effort to get some more better and deeper edumacation out there to the masses. Some companies try, for sure...

[@bc527c]

Thanks for your concern Mr my name. You exaggerate, jackhammer is rated at 100 dB. The 86 dB example is a reference to a standard measurement, it does not indicate listening habits. But what the heck, I was measuring some speakers tonight that I’m building. In the big room they were at about 90 dB 25 feet from the speaker, and about 110 dB a foot in front. Point being, if you are listening at 78 dB at the listening position the speaker is putting out an actual 94 dB just out front of the speaker. That is in a 9’ distance (I just measured that while typing this). So it’s not absurd abuse to speak of high dB numbers.

[@bc527c]

My Name The subwoofer freaks... Who install many very large subs and crank em up and waste 90% of their power to room modes... So they add more subs... And end up like this chap, who, if you watch some, finally shows the cracks in his actual hose from the subs... 150 db... kzbin.info/www/bejne/rJLXl2iLg9aNoc0

saludos desde chile. todos sus videos son muy buenos y aclaratorios.

[@akeeperofoddknowledge4956]

Thanks, Paul!

I have Fender, Vox, Marshall, Blackstar etc...Tube Amps!! 1 watt up to 85 watt Fender Super Reverb is LOUD! Different sound than what I noticed here. Discussed here are Solid State amps I presume! Very different than Tube amps!

[@airgead5391]

Even when the sensitivity of the loudspeakers in the guitar cabinets are higher than HIFI speakers in general, and they don't use an X over, you are right: there is definitely something going on in the wattage versus perceived volume. I had a chap bringing his 500W class D bassamp, and comparing it to an Ampeg tube amp it was a joke. I asked: what is that red light going on and off? It was the clipping indicator! Almost couldn't believe it! 100W of tube power easily outperformed 500W class D.

[@johnclark3067]

I have noticed this as well while comparing AB amplifiers to class D. AB just sounds more rich and full to me. Though, I probably have not heard a really good class D.

[@airgead5391]

@@johnclark3067 I don't know if there is a class D which approaches class AB. I went once to a large guitar center to pick the best class D bass amp, just as a spare for my tube amp. Most of them sounded ridiculous. The best one was an Ampeg. At home I realized that even for studying at home I couldn't bring myself to use the class D, so I kept using my Ampeg 300W tube amp, burning up 6550 power tubes, producing a lot of heat, and consuming a lot of power. Till now I never heard any class D that comes close to being good.

[@steveaustin7306]

I'm over powered my speakers by 25%. Had a couple drivers replaced under warranty years ago. I can hear them start to crap out on contious high level but nothing on transients as there's lots of head room in a 60lb toridol(sp) transformer.

[@Ostfriese777]

The most important, and most expensive, part of an amplifier psu isn't the transformer, it's the electrlytic capacitors that act as some kind of superfast hi current accumulator. When the amplifier has to deliver hi amounts of current in the split of a second the Capacitors are the parts of the psu where the Current is taken from. Most Amplifiers have a symmetrical power supply, that uses a positive and a negative voltage, and so there are two Packs of Capacitors, one for the +, and one fo the - rail. For a 25W Amplifier I use 25000 - 30000µF per rail. This gives a good push in dynamics & punch. For my 170W Subwoofer Amp I use 80000µF per Rail which gives a pretty good performance. It's really ok as it is, and I've got other things to do first, but maybe somewhen, I'll try 120000 or 150000µF per rail. A big Speaker can always handle a little xtra current.

[@nacholibre9929]

I had been 30 years wrong, thanks, I now know.

[@كورسسسكوللشبكات]

I have an Bose amplifier: 2x50w @4 ohms, 2x25w @8 ohms And Bose speakers: up to 80w, 4 ohms What's the maximum numbers that amplifier can handle?

[@univenpecalipre]

what about Ohms?

[@timharig]

What about them?

[@rickc661]

I take the speakers rated efficiency ( generally around 88 db /watt ) then take the formula that 3 db increase requires double the power. thus going from 88 db - fairly loud) to just plain loud , say 100 db. that would require minimum of 16 w. double that for minimum headroom - 30 w. then the 2 nd stereo speaker would compensate for room size. > that's talking the conservative 20 -20,000 hz continuous wattage. instantaneous peak is usually much higher and that would also add 'headroom - distorting speakers because of low headroom are baaad. that's my idea, 50 w chan. is entirely OK for an AVERAGE room / speaker combo.

[@carlosoliveira-rc2xt]

Your math doesn't add up. 1 watt = 88db does not work out to 16 watts = 100db.

[@rickc661]

what don't I get - 1 watt equals say 88 db? 2 w. = 91 / 4 = 94 / 8 = 97 / 16 = 100 db.... isn't the simple formula that going up 3 db requires double the power ? that's probably an anechoic room whereas in real rooms, there're all sorts of reflections boosting or cutting.? obviously a simplistic guesstimate, close enough for the purpose. What'd I get wrong ? @@carlosoliveira-rc2xt

[@InsideOfMyOwnMind]

Another way to put it would be all other things being equal a bigger amp sounds better. IF you're going to use it in the power range it was meant to handle cleanly and not playing whisper soft background music.

[@carlosoliveira-rc2xt]

You have it all wrong.

[@timharig]

All things being equal, have both an amplifier and speakers that exceed your desired listening level and make judicious use of the volume control so that you don't push either of their limits.

[@InsideOfMyOwnMind]

@@timharig If you're want to push either to their limits you need to upgrade.

[@dandonna852]

Does this apply to home theater to?

[@timharig]

Yes.

[@FURDOG1961]

0:00 6:10

[@randomtube8226]

I think if manufacturers would just make their amplifiers clipping proof. We wouldn't have this problem. People want the ability to to max everything out. Many dont care about how bad clipping sounds. Then they are dumbfounded as to why their speakers ceased up. It takes power to make power. But it takes even more power to supply unclipped current to your speakers.

[@carlosoliveira-rc2xt]

I recall Onkyo receivers back in the early 80s having their gain set so the amps volume would max out before the onset of clipping. Not necessarily a great idea though but dealers nonetheless used it as a tool to show their receivers were better than the competition.

[@MrDingaling007]

My Q accoustic 3050 floor stand speakers are rated at 92db/1watt sensitivy, I don't need alot watts to produce plenty loud music. I ended up buying an hyped ncore 125watt x2 (45wx2 RMS) class D amp. This combo goes plenty loud for me without straining the amp to my ears and calculations. Speaker sensitivity should be discussed too.

[@carlosoliveira-rc2xt]

What should be discussed is how sensitivity is measured in a loudspeaker. Not as clear cut as what some may think.

[@shawnwhalen8314]

"Go Big"

[@theautodidacticman_]

Bigger amp will definitely run cooler too

[@randomtube8226]

Damage only occurs when the amplifier is stressed and starts to clip. You can never send too many watts to any speaker. None of them will fail. Only when there's any clipping involved. Including soft clipping. People think that soft clipping is okay when it's not. That's what causes your speakers to fail. Nobody should ever start to smell their loudspeakers cooking after a high volume listening session. Unless you have a frying pan sitting on your class A amplifier cooking an egg lol

[@timharig]

Sending too many watts to a speaker coil turns the speaker coil into a heating element. Sooner or later the speaker melts or burns. Either way, its a tradeoff. They key is to have a big enough amplifier and speakers that will not melt or clip at your listening level, then make judicious use of volume control.

[@juanpestrada5231bdndjkdn]

Thanks paul for explanations also on the car amplifiers is the same?

[@johnclark3067]

Essentially, yes. I have a friend who has more than double the power I have on Focal K2p 3 ways. His sounds more at ease at the volumes where mine start to sound slightly strained and congested in comparison. Both systems are adjusted so that hard clipping is not possible. He has much more headroom than I do. If you never turn it up that loud, I suppose it would be a non-issue.

[@slokke99786]

Basically but you can damage speakers having too much power and not enough speaker if you have too much headroom and turn it up too much

[@johnclark3067]

@@slokke99786 That is true. Drivers can bottom out, and heat can melt the adhesives that hold them together. With power comes responsibility. Unfortunately, there are lots of folks with ears of steel who would "ride a good horse to death." My system is as idiot-proof as I can make it. It is easy to do if your source (in my case: car radio) will not clip even when turned all the way up.

[@Paulmcgowanpsaudio]

Car amplifiers are a tough breed because they are so limited by their power source. The techniques to overcoming the 12 volt limitations are to have speakers with extremely low impedance (old school) or to use a modern switch mode power supply. If it's a modern car amp then much of what I suggest will apply.

[@johnclark3067]

Paul, I apologize if you covered this already, but what do you think about anti-clipping circuitry in amplifiers? I used to have a McIntosh car amplifier that had it. Still have a Blaupunkt Velocity V7000 (made in USA, Rocktron's pro audio factory) that has it. Many people argue that it is not necessary if you adjust your gains properly.

[@dandonna3904]

I would like to see demonstration on this subject from Paul

[@simonsteamyhead5738]

But a Marshall JCM 100 guitar amp is definitely louder than a Marshall 5w bedroom practice amp.And my tinnitus is testament to that.What am I not understanding here.? Sorry for being so dim

[@Titan7170]

Using your example i think hes afraid of sending to much wattage and damaging the speaker....so if the speaker is rated at 200w peak and he has a 700w amp.....will there be a point where if he gets past 200w will the speakers get damaged....??

[@Toxicsolution23]

Buy better speakers thats my solution

[@Yiannis2112]

@@Toxicsolution23 Better has nothing to do with power handling.

[@timharig]

Yes. If he turns the volume up too high he will burn out his speakers. The question is will he? If he would, then he should be purchasing larger speakers. Paul only focuses on the amplifier but the same holds for the speakers. What really matters is what power level he will be listening at. Then he should purchase both his amplifier and his speakers to have ample headroom for his listening level.

[@Justwantahover]

When l turn the volume up just a bit louder than normal room listening l can hear the difference between my 200w amp and my 10w Bluetooth amp.

[@charliedavidson3878]

. I sold audio equipment back in 1977-1980 we sold Pioneer, Teac, Nakamichi, Luxman certified and Mcintosh uncertified . We saw the greatest failures with our smaller amps . For example we had more failures with our L80 (50 watts) and less with the L85 ( 80 watts) and none with our L100 (110 watts) on the same speakers . The results were not surprising to luxman engineers and they came up with the same reasons you did 40 + years ago . As the amps struggles it outputs trash to keep up . When we contacted the speaker manufactures for warranties and they said the same . We purposely trashed out speakers conducting our own tests . Selling systems that blow up in our customers homes is a bad look and quickly leads to chapter 7. At first out test failed because we used common sense when it got too loud we cut back on the gain . With ear protection to fool our ears we just poured on the gain . We had a total of 3 failures out of 6 all from using smaller amps we had 0 failures using amps rated at twice the speakers recommended power . We would have blown those last 3 speakers but it was so loud we had noise complaints . Our store neighbors also claimed damages caused by the loudness . Now the sticky part the speaker makers have a rating, you exceed those rating and no more warranty ? Whatever warranty means nowadays ???

[@charliedavidson3878]

@edwardschlosser1 Great points. You sound like someone that uses good common sense . I occasionally use my first stereo amplifier a Mc225 . You're right ! It was the point I was going to make if someone replied . The other extreme small amp with capable speakers . Who am I kidding I have that big 300 watt McIntosh stereo amp for bragging rights but my wife slaps me down when the music gets above a mouse fart . Even listening to headphones is too loud for her . If I ever win the lotto I'm moving to NOLA by myself and taking my loud ass system with me

[@ryacus]

They shouldn't make smaller amps to allow damaging levels then.

[@charliedavidson3878]

​@@ryacus No they shouldn't ... short answer . all speaker systems have a ceiling, it transitions from db's per watt to watts per db . When a speaker starts to transition you better have clean watts / power to spare or your amp will start to output puke and poop . Puke and poop in your speaker system leads to a cleanup on isle 8 . 2 schools of thought ; the wine and cheese 2.5 watt systems on horns and everyone else. Option 1 takes careful planning, option 2 not so much . If you are smart you'll know your systems limitations and show some restraint . Extensive research and planning pays dividends. As the great Michael Vick says I have no dog in this fight .

[@timharig]

Paul only answers half of the question. The real answer isn't about speaker rating vs amplifier rating. The real answer is about the listeners preferred listening level. Then choose both the amplifier and speakers with ample headroom above the listener's habits.

[@charliedavidson3878]

@@timharig I agree with you but we now live in the Facebook world 90% show 10% go . I agree with Paul in theory .In theory the input should have the same loudness at the starting gate . Just to make a point let's say you have a 5 watt amp vs a 300 watt amp. anyone with 1/2 a brain cell knows the 300 watt amp reaches 5 watts with a lot less turning of the knob. 5 Watts almost takes a full turn, on a 5 watt amp and maybe 1/4-1/2 turn on a 300 watt amp. There's so much this video didn't have so its really just for rule of thumb . Just a guide . Speaker selection is another video . This is just a quick and dirty guide for picking the right wattage . The quick answer is there's no limit on max watts as long as the input gain is the same. When speakers reach their limits they start to flatten out . My initial input was to point out my experience with under powering and to me that's more danger. I agree with you on proper speaker selection . I also believe that speaker selection should be solely based on demos not reviews . I call ebay the final resting place for bad decisions and no research . I believe in research twice buy once . If I had to guess on minimum watts for a speaker should be the maximum speaker rated capacity in RMS. That's more of an efficiency issue .I start at the speakers and work my way forward . Will a 105 Db speaker work well with a 2 watt amp? absolutely yes .

[@claudec2588]

My speakers are rated at 300W each my amp is rated at 120 Watts RMS. Does this mean my amp is too small? Should I be looking at an amp that puts out 500 Watts per channel?

[@bobspringer5370]

Claude C- Yes.

[@timharig]

The maximum power output of your amp and speakers does not matter. What matters is how much power output do YOU listen to them at? You then want both your amp and speakers to exceed YOUR listening level with headroom.

[@claudec2588]

This is not only counter intuitive it is also counter real world experience. I've blown a pair of speakers. My brothers kids blew one of his speakers during an outdoor party. If you can't have too much power why do speakers get blown out?

[@Snook_]

Not at all, he explained it perfectly clear. Of course you will blow a speaker if you turn it up too loud. But you need the headroom as clipping is more likely to kill your speaker on a lower powered amp than having too much power. Dynamics are also an important part of realistic sound. You need double the watts to increase the volume by +3db. So a 300w amp for example only powers the same speakers 3db louder than a 150 before clipping. These are key concepts as amps are exponential in how much power they put out to linearly double the volume. This is why home theaters need to many watts to sound correct, as THX reference level of 85db for the voice track requires +20db peaks in the subwoofer to make 105db like a theater. Well going from 85 to 105db requires 6 times the power which suddely takes you easily into the 100's and 100's of watts to do this without clipping. At least that is my understanding.

[@timharig]

It seems to me that I already answered your question in a duplicate post -- but, the answer is that you should choose both and your amplifier and your speakers with enough headroom to exceed whatever volume you are going to be using them at. If they both exceed your whatever volume you are going to be using them at, the relative ratings will not matter because your listening will not approach either of their limits.

[@chriss881000]

But u dont gain alot of wolume from 100 watts to 700watts. Around 10 db

[@jat5am]

I guess, all the talk is not about volume. The more watts, the later clipping occurs.

[@JPAudio22]

The Crown Audio website has a great explanation of amplifier power and headroom as well as a calculator that takes into account all of the factors when matching speakers and amplifiers, it should take most of the guesswork out of it: www.crownaudio.com/how-much-amplifier-power

[@JPAudio22]

@My Name I came up with 285w for my system; if my speakers were just a little less efficient 600 wouldn't be unreasonable.

[@jackneidinger9544]

I've blown out small speakers with amps. Why no discussion of speaker ratings and continuous vs. peak power? And nobody needs 700 watt monoblocks unless you live in a stadium.

[@jefflaporte2598]

If your ears aren't bleeding your music isn't loud enough :)

[@charlescalkins4732]

When I am listening to music at home I like DB level to be around 80 DB most of the time. There are some CD's I have that require more DB's. Like maybe 85 DB. Anymore than those levels makes things TOO LOUD!!!

[@latourhighendaudio]

Volume to me is critical. There is a right volume level. For me though it’s the unamplified volume of acoustic instruments. It gives me the illusion of listening to live music

[@DennisDWest]

@edwardschlosser1 It's Lawrence Welk. I've been a fan since I was about 5. Just like Motley Crue, I like it loud.

[@charlescalkins4732]

@edwardschlosser1 Sorry to say but 90 DB volume playing music my neighbors all the way to the corner can hear the music. It is Welk not Welch

[@logtothebase2]

Many amps make light work.

[@victorfeliciano6094]

love u paul u r so funny, love your video!!!!!!!!!!

[@كورسسسكوللشبكات]

I have an Bose amplifier: 2x50w @4 ohms, 2x25w @8 ohms And Bose speakers: up to 80w, 4 ohms What's the maximum numbers that amplifier can handle?

[@victorfeliciano6094]

you are the best!!!!!!!!!!!!!!!!!!!

[@MrTruth111]

Offcourse Paul is right, but I am happy with my 2x65 Watt amp connected to my 300 Watt speakers. The torroidal transformer is oversized and the listening levels I use are about 30 Watts, so still plenty of headroom, above this and it is bad for my ears anyway.Loudspeakers play a big role, I don't think many speakers out there are able to produce undistorted sound at 700 Watts.

[@Merlin-wo1kj]

So Emotiva is good stuff because Dan is your buddy? Yet he says McIntosh isn't worth the time to consider because Best Buy sells them... I own Emotiva, PS Audio, Mcintosh and Rega and think they all make some great gear.

[@googoo-gjoob]

easy answer.....MORE

[@claudec2588]

It's better to have more power than you need rather than less power than you need. Fine. I agree with that. BUT, more power equals more money. And unfortunately Paul most people don't have your seemingly limitless financial resources. What people are really asking Paul is what is the minimum I have to spend to get the power I need? To answer that Question they need to know how much power do they really need? For most people 150W RMS 2 channel stereo is plenty. 700W RMS means they've just spent 4.5 times more money than necessary. If all you need is 150W RMS, 700W RMS isn't going to improve the sound quality or your enjoyment of music. In fact, quite the opposite. Since you'll have less money to spend on the CD's, vinyl albums or digital downloads of the music you love. Not to mention less money for the other components in your system.

[@raffiequler7510]

Claude, unfortunately Paul started this channel to attempt to sell more amplifiers. His fake stories and fake laughs are just there to make it look like he is making these videos for your benefit.

[@gerhardwestphalen]

It's much easier if you just show how to calculate it. Speaker (or driver) sensitivity, listening distance, and peak level. That's all you need. Saying that you need "adequate headroom" is meaningless and just confuses people. If you calculate the value that you need, double the wattage to give the amp 3dB of headroom and you're good to go. Anything more will be useless.

[@carlosoliveira-rc2xt]

3db headroom is nothing. A lot of music has much bigger swings especially in the bass obviously. Loudness means different things to different people. How many people know the average decibel level of their music listening? And in different moods, it may change. As has been mentioned, it's a better idea to have more amp and more speaker than you need rather than too little. No calculations required.

[@gerhardwestphalen]

@@carlosoliveira-rc2xt All you need to know is your peak level (or you can work in reverse to figure out the peak level possible based on the amp you have and then never go above that point). The only headroom needed above that is to keep the amplifier in a happy operating range rather than being close to its limit so 3dB is more than enough. Those last 3dB will never be used. In my case the peak level of my main speakers are 100dBSPL at 2m. Based on that, I know that putting a 1W amp on my compression drivers is more than enough. I can just as easily calculate the power needs for everything else in my system. Of course if you're dealing with analog playback devices then it becomes more complicated since there's no hard ceiling.

[@spacemissing]

Simple: Choose an amplifier that is within the recommended range the speaker manufacturer suggests.

[@Ostfriese777]

BS

[@dorningarts]

sadly those numbers are pretty much meaningless

[@كورسسسكوللشبكات]

Thanks I have an Bose amplifier: 2x50w @4 ohms, 2x25w @8 ohms And Bose speakers: up to 80w, 4 ohms What's the maximum numbers that amplifier can handle?

[@dandonna3904]

I was told 100 present 200 watt speaker need 300 watt amplifer ???

[@myadventures8]

Yes

[@claudec2588]

If this is true, and I have to believe it is 'cause you said it, then why do speakers blow?

[@dorningarts]

seriously? Too much power was applied and they could not handle it. Paul is addressing a different issue here

[@jamieanthony9763]

Clipping from an underpowered amp/distortion