If you're looking for a lot of clean power for a reasonable price, these are the amps I use in my home theater. Crown Audio XLS 1502 Stereo Power Amplifier (525W x2 at 4 Ohm): bhpho.to/32FYD0g Crown Audio XLS 2002 Stereo Power Amplifier (650W x2 at 4 Ohm): bhpho.to/3esZoiy Crown Audio XLS 2502 Stereo Power Amplifier (775W x2 at 4 Ohm): bhpho.to/3vhFAWr *** Note: The above are B&H affiliate links. Purchasing through these links earns me a (very) small commission at no cost to you. This is what I use to help me pay for my test gear, server space, etc. *** These are great, powerful amplifiers. My only real gripe about them is they have a high SNR so if you have high sensitivity speakers the noise floor may bother you. If you have standard sensitivity speakers (

You should also do a video on power/thermal compression in speakers. People expect way too much from small drivers with low power handling.

Great video. I despise this trend to compress music until it's barely music anymore.

And, no freaking hieroglyph measurements, like foot/feet etc etc. Perfect!!! Cheers and thank you so much, Erin. 🍻😎👍‍‍.

Very helpful video; I've been experimenting with different modest amps for my LS50 in nearfield, and also spec'ing out a new system for a much larger room. So this helped me do some math to confirm what I've been hearing and measuring, with my UMIK2 and the DR numbers Roon tells me. Great stuff Erin.

Wow ! I am brand new to your channel and so glad to have found you. I have never heard anyone talk about dynamic range before and this is really interesting for me. The tools like the calculators on the Crown site are excellent links to help understand how any one value may effect your overall needs. Thank you Erin.

One of the best reviewers on utube…thank you sir👍

The dynamic range is the difference in decibels between the loudest moments of the song and the quietest moments of the song. My understanding is that single number scale represents that ratio in a succinct way. In audacity, looking at the waveforms of songs, we are essentially looking at a bucket. The bucket is only so large and can only be so full of “water” before it overflows or clips. As the waveform increases in amplitude, more “water” fills the bucket. The differences in the waveforms show that we are or are not using the “full capacity” of the bucket. When we ask our speakers and amps to recreate this change in range, our desired SPL for the loudest peaks becomes the limiting factor. If we want the peaks of our content (regardless of the dynamic range) to be at 100 dB SPL, the we will need 10x more wattage than if we wanted to reach peaks 90dB SPL. So if there is 10dB of range in a song (we would perceive that as being twice as loud) and our amp is are getting into clipping on the valleys (90 dB SPL) we need to up the wattage by 10x if we want to have enough wattage to cleanly reach 100dB SPL at the peaks. When speakers fail, it’s often because the amplifier is under-powered and thus can’t hit the desired listening level without clipping. This takes the AC signal it turns into DC which speakers can not handle for long before failing. All that to say, if know the max SPL and average SPL level you’d like to listen to, these calcs are really valuable in “right sizing” your amp

One thing not mentioned in the video is that you can play compressed music at much lower levels while still hearing everything clearly. That's a good thing for the way most people listen to music these days. Music with high dynamic range can trick you into turning up the volume to hear something that is soft, and then it deafens you when the real music plays. Some albums do this on purpose, like Pink Floyd's The Wall is a classic example.

Great info, thanx for sharing. It's not how loud one can play, but it's the dynamics it can handle. Eye-opener for me ❤

You don't need more than 3 dB of headroom on the amplifier. Amplifier headroom, also known as peakroom, is power capacity which you don't use. It is there to ensure you don't need to drive the amplifier into clipping. You can listen to pretty much any kind of music, with any dynamic range, as long as the system gain structure is optimised to take full advantage of the audio source full dynamic range and ensure the audio signal has the best signal to noise ratio before entering the amplifier. The amplifier has input sensitivity switches on the back panel and input sensitivity controls on the front panel (yes, those rotary knobs are not volume controls). The back panel sensitivity switches are used to match the nominal operating level of the sound source and the input sensitivity controls are used to compensate for the sound source maximum output level. The overall volume of the system is controlled by the audio source. In a system with correctly set up gain structure, the amplifier input sensitivity controls don't ever need to be turned up more than the 12 o'clock position, depending on the audio source maximum output level.

Great video! I really enjoy your channel. I'd also add room Treatments have an effect on db loss over distance. A room with too much absorption is closer to 6db of loss over Doubling of distance where as a room that's properly treated with a mixture of panels and especially with diffusion like combo panels at the ipsilateral and where needed will have more energy sent back into the room and would loose more along the lines of 4db per Doubling as the reflections are part of the sound power. At a distance of 12' that's a possibility of having 4 or so more db at the seats from reflections.

Yep so many people forget the sensitivity of their speakers, the distance from their speakers to their ears and importantly the dynamic range of the recordings! 10 feet in the HT, and 7 feet in the home office audio stereo room with 90db speakers at 8 Ohms! Great video as usually thank for the website information regarding dynamic range or recordings! IMHO High resolution music in multichannel is outstanding!

Excellent content and valuable information. I appreciate your real world approach. There's just too much nonsense out there to sift through. Its refreshing to find real answers. Thanks for the work you're doing Erin.

Thanks for this video and the links to the tools! Great help to me as I'm just getting into this hobby and sometimes the amount of data needed to make an informed choice is such a huge barrier to entry

Thank you for all your informative videos!!!

Just subscribed. Learned a lot from this video. Never considered that just because my amplifier makes my music loud enough that because it is only 7 watts per channel that there is possible compression and clipping going on that may be effecting the dynamic range. Explains why some speaker manufactures recommend a min Watt amplifier. a friend of mine also found his new Klipsch speakers sounded like crap until he hooked up a larger amplifier then they sounded good. Thank you for this great explanation.

For home theaters reference spl is 85dB continuous with 20dB dynamic headroom for each loudspeaker. And 95+20 dB for the LFE. Thats for 20Hz-20kHz 115dB at 20hz can be a challange for the speakers. A somewhat capable(normal/good) 12inch woofer in a sealed box can manage around 103 dB in room. That means youd need at least 4 such boxes to reach peak reference lvl. But since that would be pushing the driver quite hard you might want an additional 2 or 4 drivers. For similar driver in a well designed bass reflex box you can divide the figure by 3. So around 4 such boxes can be something to aim for. Around 300W per driver would be needed for the bass reflex. Half of that for the closed boxes. Remember also that for every loudspeaker you set to ”Small” that bass information goes to the LFE. So actually you need even more capability in the bass/LFE if reference lvl is to be reached. Also movies contain sounds below 20Hz. Some movies goes down to 7 Hz or so.. (for every halfing of frequency you need 4x capability) I find that 85 dB average listening spl is too loud. 75 is probably closer to what most find enjoyable. That would mean 95dB peak is needed from each speaker. Id say 75 dB with 20 dB headroom is pretty nice starting point.

Great to see you talking about the need for dynamic headroom with classical music. I think I had arguments about this on hydrogenaudio.

Great topic and video, Erin. 👍 Speaking of DR and Average SPL, I must have been listening to your video with just one speaker, and in an anechoic chamber, because your dialog level was at least 9dB down from the KZfaq average. :-P Both your own KZfaq channel Animation/Sound Bite and the KZfaq ads blasted me out when my volume was set to a comfortable level for your dialog, which was at Max Volume on my tablet in a relatively quiet room. ;-) Love the teaser in the thumbnail as well. 👍

Thanks so much, I got so frustrated when people insisted on the 1 watt concept that never sounded right to me.

Erin, found your channel a few days ago , and now I'm going through many of your videos. Great job! I appreciate the way you combine subjective, yet critical, listening with real data to characterize speakers. I do have a question on this particular video. I apologize if it's already addressed in the comments (I looked some but didn't see it). At the end, you mention that a second speaker adds about 6 dB and the room about 3 dB. This is in regards to the SPL, correct? So if we use the Crown calculator for a stereo system, would we drop the listen level by SPL 6-9 dB and then the resulting amplifier power would be per channel? Or how would we do that? Thank you.

This explains a lot. I wonder that in room response on published by manufacturers actually consider the combination of both speakers not one

Loved the video, really useful information in this! Now if only sensitivity ratings were consistent between manufactures...

Great video - thank you!

Hello Erin, nice video but I would you surprised me with your 85 dB average spl part. To me, that is the so call THX reference level that would be as loud as what one would hear in a good movie cinema. I really doubt your claim that most people listen to 85 dB average. For me it is more like 70 to 75 dB but I can believe that if you do a survey using a large enough sample, the average could well be up to 80 dB, though not 85 dB. On top of that, it is better to allow for 20 dB headroom for peaks. Also, your suggestion that one could find out with a phone app, but you may want to mention that many of those phone apps are not that great because some don't even tell you what "weighing" they use so they should pay attention to the app that are using. Any of this is not a big deal except when you relate it to "how much power you need...", as we all know even a 3 dB difference in the assumption made would result in 2X the difference in terms of amp power output requirements. Thanks again for a nice presentation.

Thanks! Great post making a complicated idea really practical

Wow, super helpful and detailed. Now enrolled in Erin's Audio school....

Very educational. Your input about hi-res music would make a great topic for a future video. There's so much disinformation and anecdotal hearsay out there on the subject.

Very important video for starters like me thank you Erin

Once before the 21 century started, there was a dynamic range. That is pretty much why I don't listen to new music. Also some of my tastes changed. I tell you up some point I can take chopped peaks, but so much popular music sounds bad, and the same goes for re-masters, (masters of disaster). Even though my hearing is nowhere near as good as in my youth, I would expect things to be better than 30, 40 yrs ago since equipment allows for better SQ, an irony as things went other way around (the use portable players with limited output ?) As for amplifier power - better to have more than not enough, especially if the impedance goes very reactive. Great topic as always 👍

Morning Erin, interesting video. It is funny how complicated such a seemingly simple topic can be. I think that your basic premise is solid, there are some some aspects that are missing. One thing is the way dynamic range was used. And another viewer touched on this. If you have a recording with a given dynamic range, will say 10 db. And you listen at 85 db, the 10 db dynamic range is the difference between the quietest and loudest music passage. So the peak transit from your 85db average volume may only be 3to 6 db above the average level of 85 db. Let’s use the +6db as an example. So if you are using a speaker with a sensitivity of 85db 1w 1m, and you need to reach that +6db dynamic peak, or 91db peak. 85db=1w, 88db=2w, 91db= 4w. As you see the power dubbed for every 3db increase in volume output. Your power needs are not nearly as demanding as that calculator on the crown website indicates. I have 90 db sensitive speakers that I sit say 2 meters from. My average listing level is mid to upper 70db range. I listen to music that is usually dynamic so my peek sound pressure at my chair reaches 85-88db. Between +10-12db. I have measured the amplifiers output at the speakers, and the peaks are 1/4 and 1/2 watts. I know that I listen at a quieter level than many, but I would bet many people would be surprised what kind of power they are actually using when they are not trying to blow the windows out. And another thing is that most good amplifiers are rated 20-20,000 hz continuous both channels driven at what ever load, and % distortion. But the same amplifier is probably capable of several times that output for a transient peek, especially at mid and high frequencies. So a good 50 watt amplifier may deliver 100w or 200w output to meet transient musical peeks. All to often qualify and quality get confused, or are interchanged these days, and this is definitely one of the best examples.

Excellent, learned something today!

Wish i found this video a long time ago lol. Very good info thanks!

In 'la nouvelle revue du son' magazine they tested dynamic range needed to play without clipping 'bolero of ravel' , speakers were voice of the theater 100db/w altec ....they concluded 2x 55 watt needed .....for uncompressed dynamics at the fortissimos....

I have a small room (15 m2) and sit about 2.5m from my Mains. Peak listening Volume in Movies is a around 80db, so my power requirements are pretty low. I once measureed the power draw for my Height Speakers...they were driven by an external Class D amp. The draw was not even 0.5W for both Channels. Of course there will be Movies where that number is larger, but a lot of the time those Speakers aren't doing any heavy lifting so the amp can give most of the Power to the Front and Center👍

Can you please discuss the impact that output voltages of the source can have on the data that you provided here. I have sources that range in output voltages from 2 volts to 9volts RMS and you can definitely hear the difference when they are connected to the same amplifier.

Great content, just discovered your channel. You also just made me feel justified in purchasing a monolith 7x! Lol. Great videos keep up the great work.

Amazing content!

Some companies have a methodology to their power ratings, for example using crown calculator with specs of my JBL speakers and subs I have concluded that the minium power rating is for max SPL they list on the product with 3 dB amp headroom and the maximum power rating is for max SPL they list and 6 dB headroom. In calc you have to take into consideration this 9dB that room and second speaker usually adds.

In terms of movies, what will be a good number to use for the Amplifier headroom on the calculator?

Great video! Thanks

Correct me if I’m wrong but 1 W/m is efficiency. 2.83 V/m is sensitivity. No one explains this but to me it’s simple. Efficiency describes output per unit power Sensitivity describes output per change in voltage regardless of load Great video. I think your content is unique and brings a lot of value

Good info again Thanks

Working on building a 3way with about 96 ish db @ 2.83v 1 meter @6ohms nominal. Specifically so I can run it on just about anything. Combine that with a Hypex amp for the lowest distortion amp for the money and it should be something special.

I find it rather perplexing that you can create a video about audio quality, talking to a camera, showing graphs and discussing all sorts of technical matters..and not once demonstrate a single concept by playing even one short clip of music.

Great stuff.

I've been wondering this for a while, but i think i can wait until i have better speakers and get a Parasound or something to add to my AVR.

Very nice video and explanation indeed. Some clarification in terms of required power: assuming that and avr can provide a total of 125W per channel (so 250W total available power correct?), and based on an average 87db sensitivity of 9 speakers in a 5.1.4 set up, if I want to have 85 dB at the listening position with 10db headroom would require ~40W per speaker (360W total). Does this mean that this amplifier can't provide the required power?

All I ever look at is the sensitivity, ohms, and frequency range at 1 meter and 1W, so I get some idea. I'd prefer to know dispersion in degrees, at what power output you'd blow the tweeter, and other things that help me build out a home theater.

There are free PC apps out there that allow you to change the volume of mp3 recordings. They will automatically analyze all your recordings and suggest a volume to adjust all your songs to that level so they no longer clip (hit that ceiling you're talking about), and then apply that volume-equalization to all the other recordings to match. This will give you dynamic headroom back. The app I use is very fast too! This is one advantage of using mp3's instead of CD's (also you have store thousands of songs on one thumb drive). You can fix many bad recordings, but maybe not all of them.

Very cool

Good day I’m trying to find out exactly what to set my AVR in regards to dynamic range and it’s not a lot of videos that really work on stuff for senate in speak more on speaker.

Love Meteora, how can I get that low compression 'cassette' version? Is it really cassette tape or what?

brilliant, again

How do we factor pair of speakers and room enforcement when inputting to the crown calculation? Should we Increase the speaker sensitivity? Ex: 1 speaker in anechoiec has sensitivity is 82 then when calculating power for a pair in room, can we input sensitivity to 91?

The only caveat I'd give to the Dynamic Rage Database is when the dB range is pulled from analog sources like vinyl or cassette. For whatever reason, the software will almost always over state the dynamic rage of a track or album when compared to it's CD or lossless file counterpart. Vinyl typical dynamic range is limited to 55-60dB where as CD is 96dB and cassette is around 70dB. While your example is still very valid, it's worth mentioning when looking at the database lists.

There is also another important thing not considered often. And that is .. how loud can the speakers in question go without reaching its mechanical and thermal limits. Can it even give the dynamics the user wants.

Dear Erin, please tell me which was sie speaker withe super liner frequency response in your video?

Great info, very interesting taking into account music dynamic range. What about movie dynamic range?

I just compared a Crown 300 wpc against my 90 wpc Yamaha. They sound identical at all reasonable listening levels.

Using the same speaker, would 2 amplifiers use the same amount of power for a given spl? If the distortion on both is low, why buy an amp with high wattage? thanks.

Here in belgium at hifi show in brussels, most of the demos went into clipping , expect the higher efficiency speakers....

I'm a member in a few McIntosh-related Facebook groups, and often people will ask how much power they need. A lot of people give advice, but I've never seen anyone ask what the person's room dimensions are.

Max power for a speaker is very frequency dependent . High freqs are electrically limited , low freqs are mechanically limited (X-max) You can blow up (mechanically) a vented speaker with a handfull of watts if you supply it a low enough frequency below its resonance . I once demonstrated that on a pair of dual 18 PA horns that were only going dow to 50 Hz

thanks man

You can never get too much clean amplifier power with the emphasis on clean i.e. no distortion. Remember the speaker load on the amplifier will affect the distortion depending on the amplifiers ability to drive lower speaker loads i.e. 4 ohms or less

I have some JBL where rated sensitivity (2.83V/1m) is 92dB at 8ohm. What puzzles me is why just some powerful amplifier (300+W in 8 ohm) really control this speakers and make it sounds good?

check muddy waters - long distance. 19db Dyn Range

I had a Crown Audio XLS 1502. It was a PA amp and never an audiophile amp. I replaced it with an ELAC Alcheny amp; so much better.

Hmmm so according to the Crown calc I need an amplifier with 1 watt? My numbers are 3 meters from speakers, 70dBSPL, Speaker Sensitivity is 93 (non anechoic), Amp headroom is 15. I calculate and it says 1 watt. I bumped up the dBSPL to 80 and it calculated 14 watts. Does that seem correct to you? I'm listening to School by Super Tramp and my volume is set to 55 on my Marantz SR7007 AVR which says it is 125watts / channel. My speakers are Paradigm Reference Studio 100 v5 floor standing speakers.

I think that the levels you use in your video might be a bit high. I personally listen to music with 85 dB peaks with more dynamic tracks hitting 90. With those number you have way lower power requirements. And from a video darko did most people use that level of even lower. But overall nice video

@Erin's Audio Corner Would love remasters to be released of those Linkin Park albums that aren't brick-walled!

I just measured mine. 2.2 meter listening distance. speaker sensitivity 88db, 75 db average listening volume. 20db headroom. I got 24w only required. In theory, for two speakers this number is even lower. Too good to be true? I got a decent mid range AV receiver that has measured 105w 8 ohm output. 185w 4 ohm output. Many would argue still not enough the drive my B&W 700 series floor stander. Sort of they need high power/high current amp to drive (to bring up the bass). minimum 200w etc. Is it Snake Oil or real science? A bit confused. The speakers design/material used should be a factor for this calculation?

Some people think you need hundreads of watts but you will be enough served with 80 Watts per channel as long as its high current, current is almost more important

@17:22, I thought doubling of sources was +3dB? I only hear +6dB when talking about subs.

What are the speakers in the Thumbnail

My understanding is that dB - eg say 90 dB - is an * average level . And that dynamic range is from the minimum to the maximum. eg 10 dB of DR on a 90 dB pair of speakers is a range from 85 to 95 dB If that is correct, when using the Crown calculator, rather than inputting the full dynamic range of 10, you should input *half the music’s full dynamic range - for the part of DR that is above the average level. Is some part of what I’ve said not correct?😊

Any speaker over 90dB sensitivity is usually NOT acoustic suspension it has a tuned-port woofer like Cerwin Vega (i.e. there is an air intake port on the front or back of the speaker). These types of speakers aren't very accurate.

Any way you measure it, i believe a good quality amp that puts out between 250-350 watts per channel and that can handle a 2ohm load will be able to deal with any speaker you throw at it and play it loud. Older music will vary because of the recording quality and output.

I have resolved this topic as follows: I hear music at a regular or maximum volume and a loud movie at for example -20dB. At this volume points i measure the peak voltage at the loudspeakers. I also know the maximum peak/rms voltage of my amplifier under all impedance conditions from my own measurements. With this values i can calculate the real voltage headroom at music or the maximum setting of my receiver at movies. The way over the voltage is the most complex but also the most precise approach.

Revue du son , magazine did compression test, speakers were altec voice of theater 105 db/1w ...music : bolero ravel....with less then 30 watts compression was noticed..at some frequencies.....at most demos in audiofares i notice lots of clipping and distortion when demi tries to equal life sounds....thats why old jbl 4350 monitors are not broken when playing music instruments through the mics directly!!....imho for real dynamics , most commercial speakets cannot handle....and the watts cannot compensate...for crestfactor...not to forget that 1% efficiency is speaker with 90db/1w....you need 115db1/w to get 45% reference efficiency....a rogers ls3/5 has 0,1% reference efficiency , but the were just cheap small speakers for bbc bus mobile short voice listening...

Erin, great video. But 85dB average listening level is pretty dam high. It's obvious that listening level has to do with personal preference and even cultural habits. Just keep in mind if you want to preserve your hearing and and average of 70 to 75dB is more than enough. I certainly keep my listening level lower, between 65 and 70dB. cellphone apps SPL meters are way off, I have my calibrate professional SPL meter, it's readings are very very different from the cellphone app.

14+ is pretty low still. The 16 bit red book cd format allow for up to around 24dB dynamic range! 😲 I find it very sad how people are talking about needin ”lossless” audio and hopping on Tidal etc while the recordings are more like 6-8 bit resolution.. For alot of modern recordings even the 256 alac of itunes or 320 bit that spotify offer are more than enough quality. For an even better tool for evaluating recordings I can recommend the program Masvis www.lts.a.se/lts/masvis

Pretty sure I need a more powerful amplifier for the treble portion of my active bi-amp speakers. kzfaq.info/get/bejne/jtSansiSz9e9cYE.html I don't think the Power Guard circuit should go in rhythm with the music. If you watch the video please ignore the mess, I'm packing for a big move.

Should be added that, if you are using "fullrange" floorstanders limited by AVR to 80 Hz, they will need significantly less power than the calculator says. The bass region is the most power hungry so if you highpass it, you will need lesser amplification for same SPLs. Am I right?

Very interesting! Are you an engineer?

Some people confuse loudness with dynamics. Ain't the same thing. We often see loudness used to compensate for poor dynamics. Not even partially successful.

The calculator gives the required amplifier power in watts, but how does this relate to amplifier power ratings? You say the figure should be used for the power rating at the relevant impedance for one's speakers, but should one be looking at a power rating done at 1kHz THD=1% or 20Hz-20kHz with a much lower THD %, or something else entirely?

I love to see speaker test on common speakers on the market like Polk RTI a9, Klipsch RF82, Polk Audio RTI A7....etc etc common stuff sold in marketplace

The introduction of the iPod is what led to all of the horrible mp3 compression, so the music would sound louder without much amplification. Music released prior to the iPod is much quieter, but with excellent dynamic range, compared to tracks after the iPod became ubiquitous. In short, the iPod ruined digital recordings. It's one reason that vinyl records have become popular again, just because the digital recordings suck so bad....

power requirement also goes up if you add dsp, i max out my preamp volume since my 100 watt power amp can't give it any more.

All I know is I generally don't exceed 9 o'clock so very low power, some classical music needs more when Loudness is about - 20dB lufs, unfortunately these records are very rare. With super compressed music I can't stand it loud.

I learned that my lust after 2000W class-D monoblocks is warranted.

On my AVR I have the level calibrated and use relative scale, here are my average listening volume levels: Movies via cable: -8dB Movies via disc: -12dB Tv via cable: -16dB Music: -30dB to -15dB depending on how compressed it is. But, as you can see, I sometimes use +10dB (10x wattage) when watching movies compared to music.

And that’s why Purifi 400w rocks when it comes price to value

So are you saying I DON'T need a Zapco DC750.2 on each driver in my car??

I got the 1002. I wish I'd gotten the 1502. Anyways, great video. This could help a lot of people.

listen at an average DBC level of 85??? sir, I listen to my rock and pop songs ( Im 63 and listen to ABBA, ozzie, acdc, etc.) at an average of 95-105DBC and 80-90DBA. peaks reach 110-115DBC. my system is 4 radioshack 15" woofers per side in a 27' X16' living room, my system does 101DBC at 2.83 volts per side ( 1 watt into 8 ohms). I NEVER have to go above 40-50 watts, Ive tested the system with a 500 WPC amp and I reccorded 123DBC average at 13 feet!. I get NO enjoyment from music at 85dbc, I have to feel the bass hitting me in the chest, and that requires 95-110DBC levels. NOTE!!!, I limit my music listening to 30 minutes a day no more than 4 days a week to preserve my hearing at those levels. .

Im at 245W x 2 @ 4ohm