I am always wondering which one is better, bookshelf+subwoofer and floorstanding speakers. The common answer is depends. With low to medium volume in a small listening room, bookshelf+subwoofer could perform as good as the floorstanding. In a large room, especially when playing dynamic media, you are better off with the bigger boxes. Here we assume that you have the room treated for sound reflection/ absorption, enough amp power and same pre-amp/DAC/media source.

Years ago, I paired M22V4s with 80wpc NAD integrated amp. It sounded good but distortion prevent me to push higher the SPL. I was told that the amp was taxed. So I replaced it with 250wpc Bryston 4b ST and add one EP500. It sounds better at high volume but there are still times I feel harsh sound for certain music.
Few days ago I tested M3V4s. There were few findings that made me think how the different media impact the performance.
1. How come the big sound could come from the little pretty boxes? I could push the volume up without too much worry about the distortion. I could play vocal, jazz, blues, solo instrument and even pop music with deep bass without issues.
2. The bass is very noticeable even though it is not supposed be according to the specs. Then I realized that it was because the sound is so clean so the bass is clearly separated from the mid-range. Once you could clearly hear the drum and bass, I guess that mentally you feel the bass and are satisfied. This could explain why some viewers said that a sub is not necessary.
3. But, the similar issue still exist when the volume needs to be turned down to play certain music, like symphony or something very “busy”.

So the question is: why? Why the "crowd and busy" media, like symphony or action movies where multiple instruments/sound sources produce different sounds at the same, would push the speakers to the limit, especially in high volume? While at the same time “less crowd and busy” media have no issue.

I am a Telecom engineer with some knowledge of sound/light/electronic-magnitude waves. No knowledge of speakers at all. So I just try to explain the reasons and hope some experts or even speaker designers could shed some light on it for me.

Definitions first. Sorry if I start to bore you, please skip them and jump to the conclusion.
1. In physics, sound is a vibration that propagates as an acoustic wave, through a transmission medium such as a gas, liquid or solid.
2. In sound, amplitude refers to the magnitude of compression and expansion experienced by the medium the sound wave is travelling through. This amplitude is perceived by our ears as loudness. High amplitude is equivalent to loud sounds.
3. Frequency in a sound wave refers to the rate of the vibration of the sound travelling through the air. This parameter decides whether a sound is perceived as high pitched or low pitched. In sound, the frequency is also known as Pitch. The frequency of the vibrating source of sound is calculated in cycles per second.

byjus.com/physics/characteristics-of-sound-wavesamplitude/

4. How do speakers work? As an audio signal is sent through the voice coil and the musical waveform moves up and down, the voice coil is attracted and repelled by the permanent magnet. This makes the cone that the voice coil is attached to move back and forth. The back and forth motion creates pressure waves in the air that we perceive as sound. For high frequencies, speakers must move very quickly. For loud sound, the cone has to move a long way. Distortion occurs when the cone move way beyond what it is designed to.
Here is a great website to understand how speaker make sound with animations. https://animagraffs.com/loudspeaker/

5. At any given time, the speaker produces just one note. If there two notes in the sound , they form one unified wave but your ear perceive two notes. If there are 20 notes in the sound, the unified wave will combine all of them so your ear can perceive the.

Analysis:

1. The speakers need to move fast enough to reproduce the sound. When you play a music with only 3 instruments plus a vocal, the unified wave is not very complex. Even you play it in a high volume, the bookshelf speaker with only one tweeter and one woofer could handle it clearly.
2. However when you play a symphony, you would have to handle a very complex unified wave. It means that the speaker has to move very quickly in a dramatically way jumping from one frequency to another in a very short time. If at the same time you play it in a high volume, the speaker may not have enough time to jump quickly from one frequency to another while the cone is at its further position to its middle location.
3. For floorstanding speakers, the workload is spread among more drivers. That means each driver is working at a half volume if you have double number of drivers than the bookshelf speaker. At a lower volume, the speakers handle the complex wave very well.
4. I call the less crowd/busy music as less frequency-dynamic music since it has smaller amount of notes. The crowd/busy music is high frequency-dynamic music since it has larger amount to notes.
5. I call the music with dramatic changing volume as volume-dynamic music.

Conclusion:

1. Good quality bookshelf speakers (with a sub) can play as well as the floorstanding speakers in a low to medium volume most of the time for most types of music. They also work well in home theatre setup because many workload go to centre/sub/surround speakers.
2. Good quality bookshelf speakers (with a sub) can also handle volume-dynamic music in a high volume to some degree.
3. Ggood quality bookshelf speakers may still struggle to reproduce frequency-dynamic music in high volume.
4. Good quality floorstanding speakers are needed to handle frequency-dynamic music in high volume.

Just my two cents. I might made some mistakes to comment on something which I am still learning.

Most of the time, people only talk about the volume-dynamic requirement which requires high power amp to avoid distortion. I am thinking that frequency-dynamic should be put into considering when choosing speakers.

I believe that Axiom's designers know it well:)

Hey Rock, nice work on that. Really interesting stuff. Really enjoyed that with the morning coffee.

I think the source / quality of the media being played makes a difference too in reducing or smoothing “ busyness”.

I might just be making this up , but I would think the cleaner the frequency is coming in the easier it is for the voice coil to work it’s magic , a clean leading edge. Thus reproduction of that signal has more “ resolve “.

Please correct me here as I have ZERO training in any of this. Just my own study.

Thanks for the encouragement. I am learning right now.

Your point actually completed my thought. Clean media source consists fewer but only accurate notes for the speaker to reproduce. Thus the unified wave is less complex resulting cleaner sound. Bad recording consists additional wrong notes which makes non frequency dynamic music into frequency dynamic music.

Couple of quick comments:

#1 - if you have small speakers/drivers at medium high volume you are pushing the drivers to the point of non-linearity where cone movement doesn't track signal. With enough design effort you can make the speakers keep sounding good in that non-linear zone (Ian mentioned this explicitly) but if I remember correctly when you have multiple frequencies at the same time ("busy content") then you get IM distortion once the driver moves into the non-linearity zone

#2 - IIRC there isn't a sharp divide between "linear" and "non-linear", more of an "it starts getting worse at zero" kind of relationship

#3 - I have always preferred bookshelf speakers when I was playing at volumes they could handle - it may be as simple as a smaller driver array providing better imaging with all other things being equal - but for clean "wall of sound" louder playback I always end up with floorstanders

#4 - one other contributor to good bass on the M3 is the base bump between 70 and 150 Hz from cabinet/driver tuning (check the frequency response curve under Specifications). I find it enough to be noticed but rarely enough to be a negative

#5 - my impression is that cabinet resonances can also contribute to "busy" content sounding worse than "simple" content but I strongly doubt that is a factor on M3's

It's arguable, but I still find M3's to be some of the most surprising speakers you can listen to in terms of the perceived clarity of sound. I say "perceived" because strictly speaking the other Axiom models offer even a bit more clarity in the upper midrange and because a bit of the perceived bass clarity comes from the bass bump, but the overall result is very (very) "listenable".

The M5HPs are still "better" in pretty much every respect but it would be really interesting to run a varied group of listeners through an M3 vs M5HP test and see what they prefer. My guess would be at least 50% preferring M3's.

Thanks for more insights and great info.

I made a mistake here where I tested M2v4 not M3. A typo. Sorry for that.

I guess that the floorstanding speakers have to deal with complex issues bringing by multiple drivers sharing the same spectrum of frequency. Bookshelf doesn't have that issue to deal with so the imaging could be better.

Let's say two tweeters produce the same note at the same time. However there are no identical tweeters in the world even they are manufactured by the same factory. The supposed same sound coming from multiple speakers actually are slightly different. When they are combined into the sound we hear, slightly different frequencies of the same note will make the sound less cleaner. That maybe the reason why imaging of even a small box like M2 with only two drivers could be so good.

You mention , Rock, at the start of your mini lecture, that assuming a treated room for reflections et al......

I wonder if it’s necessary to define the size of room or better yet ( my real question here) where does room measurement ( for volume cubed ) end?

For example, my main living space is 750 sq feet with 8 foot ceilings. There is a dividing wall with a large open pass thru “window “ into the kitchen. And an open staircase up to top floor to another 750 sq feet and sane stairwell down to the bottom floor.

How much of that volume cubed really matters ? Does the open spaces connected together matter in terms of needing to be pressurized by the speakers? Or do the little wall and corners and 90 degree angles cancel those out?

Does this idea of volume of space have an effect on “ clean and busy music? Am I losing out on clean as I lose “ linearity “ to these spaces?

I’m not sure if I’m explaining that very well. I understand that a larger space is desirable for good imaging and soundstage ( thanks mojo for helping me learn that ) but I would do better if I reduced the space to have lesser reflections by way of amount of volume cubed or by softer surfaces and absorption or both?

Wow. That’s a mouthful but I think you guys get the idea hopefully.

Short version: What room size and shape is ideal for full range listening with busy music and still having good imaging and soundstage and not over taxing the speakers and components into distortion.

Yes. Less drivers means better quality in terms of timing, assuming the tweeters are of relatively good build quality.

More drivers are said to producing comb filtering effects but I recall that being debunked to not really mattering in terms of audible effects.

Please correct me here anybody. I’m just going with what I’ve read and learned and may not be correct as my understanding is layman. Cool topic though.

Hey Kodiak, I think that other people would answer your questions better than me.

Here is my two cents:
1. The open space reduce the reflection of sound which may require you to increase volume which may affect the clarity for frequency-dynamic busy content.
2. We need walls to reflect sounds so the music is not dry. But we also need to absorb the first reflection sound so there is not too much reflected sound to make the music less clean. Lay a blanket in front of the speakers, put cotton pillows on the couch, hang a sound absorption decoration artwork on the walls, something as simple as that could help.
3. When it is hard to treat the listening room, please try near field listening where you are very close to the speakers to form a same distance triangle. Place the speakers far away from walls as much as possible.
4. I notice that you have M60ti. V4 version is way better than ti version. Check the B-stock or refurb products, even M2 would be much better in terms of clarity and imaging.
5. Small bookshelf speakers are very easy to place and get good results even if the room is not ideal.

Thanks Rock. That’s a good answer you gave me I think.
I really enjoy learning about this stuff.

Yes , m60ti. V4 is really good...... I think I’ve conversed with mojo hundreds of times about v4, ( in a good way.) Story of my life!!!! I’m stuck with these for awhile. I bought them refurbed as a cheap way to get some reasonably good floor standers ( and to hear Axiom product ) to just have some music in the house. My ancient Sansui got blown up. I didn’t anticipate loving these m60ti and fully drank the koolaid and now I’m really into this hobby. I will upgrade at some point. I’m trying to not talk about upgrading bc I feel I plague this forum with my upgrade ideas and never buy anything!! I’m constantly looking at the b stock and refurb even though I can’t really pull trigger right now. So I’m trying to learn more and make what I have as good as I can.

So I love when these kind of topics come up that you started. Learning is free!

I think I’ll be into this hobby for quite some time. I get more enjoyment out of music than watching tv or movies.

Can’t beat goosebumps and saying out loud to myself “ my god “ when I have wow moments. So yeah m60 ti. Maybe I’m just easily impressed? Or haven’t heard enough speakers to have a “ palate “.

Thanks for the good topic starter. Interested to see what others post later on.

At the end of the day, it is the music which makes us emotional and satisfied!

Very True Rock ! But, I will always be chasing and waiting for the moment when I can upgrade.....until then I will enjoy the music for sure, the discussion, and will feel really good about my upgrade as i wont be able to say i didn't do my research! When it does come time i could see trying out a couple different options if I couldn't narrow it down.

Edit: Remote working is great! I can just be on the forum all day and get nothing done! Ha.

Working from home allows me to play music in the background and avoid long commute time. That may be one of the benefits we get from the pandemic:)

Rock, it's possible the more complex music you are listening to has a higher dynamic range. As a result, the M2s are being pushed into their non-linear operating range leading to greater harmonic and intermodulation distortion as John said. I've maintained the M2s with sub at 80Hz crossover are good to 12 feet MLP for the vast majority of listeners. I am curious what your sub crossover is and how far you're sitting.

BTW, have you confirmed that your sub is not distorting?

Large speakers are great as long as they don't overload the room and can acoustically disappear.

Rock, "frequency-dynamic" isn't a thing per se. What is a thing though is intermodulation distortion. If you play music that contains simultaneous highs and lows, and you play it loud enough to operate the speaker in its non-linear range, then the highs get modulated by the lows producing unintended frequencies. This is IM distortion. The same happens BTW in passive or active antennas.

Moving to a speaker with wider specs is the answer. This may be a floor-stander or a more sensitive bookshelf.

Regarding multi-driver speakers, each driver is akin to an antenna. If the radiation patterns are not coordinated, then you end up with unintended directivity. This is why, with the active LFR1100, Ian was nearly driven insane coordinating the patterns of the various drivers.

John is right. All things being equal, less drivers results in better sound. But things are never equal. That's just fiction.

That's a very good point Mojo. I don't use receiver for stereo listening. The amp does not filter low frequency for M2.

intermodulation distortion could be what I hear at the high range.

What are the questions? Might be able to help. Too lazy to read all that.

Been a while since someone did a room build. Pretty good excercise to answer everything then. Rrlev has a room on the go, but he is paused for now.

Just buy this book and follow the directions:

https://www.amazon.com/Handbook-Sound-Studio-Construction-Recording/dp/007177274X

We are taking about if busy music have more impact to bookshelf speakers.

I just tried the M22 with or without crossover with ep500.

The bass filtering does improve the sound somewhat. But the busy music still has more impact on the high range than a less busy music.

So my question to Mojo, does IM in the high range also cause some distortion?

When you cross over a speaker to a sub, some bass still makes it through to the speaker. So if you listen very loud, IM distortion will still result from the bass. Of course it's not only bass that causes IM distortion. Mids will as well when pushed hard. v4 mids can take more than earlier versions.

Perhaps though, the tweeter is being pushed too hard. Pre-v4 tweeters can't take as much tweeting. Or, the receiver is distorting.

Thanks Mojo. My knowledge base is getting bigger!

BTW, the higher you cross the M2s, the more they can take. Of course there's going to be a point where sending too high a frequency to the sub no longer sounds satisfying.

As for multiple tweeters, even if they are completely identical in response, they will sound bad if not properly spaced on the cabinet and crossed over carefully. Just like two antennas whose radiation patterns will interfere unless those patterns are managed through phase and amplitude diversity of the source signal.

How loud are you listening to the M2 or M22s. They can get pretty loud in a typical room. Haven’t notice any distortion IM or otherwise. I do run the with a sub.

I normally keep it to low to medium volume and it sounds great. I dont have a professional sound meter to measure the SPL.

There are times that I want to feel the powerful symphony works but I guess that is a too much ask for small boxes.

In Telecom, there are many technologies to cancel the interference. I guess that there may be many similarities. Very interesting topic.

Rock, just curious how far away you're listening from.

About 8 feet

Geez, yeah...you like it LOUD! Active LFR1100s for you.

I think either he’s already blown out his ears and needs an extra 10db boost To get him back to normal
or something else is going on ... other then the speakers.

That could be. Most of the orchestra recordings out there are garbage quality making listeners think they need to turn it up super loud to get emotional impact. It just ends up sounding worse. Rock, you sure you listening to good quality tunes?

Could also be something in the audio pipeline is hitting clip (for example some levels maybe set way out of wack)

Hey Rock, what song can you share you notice problems with. I’d like to try it out. At 100db.

That is what I want!

Lol. Lets get this sorted. It seems like a clipping issue in your chain or you are clipping your amp.

Can you walk us through your signal chain. What are the items below in your setup.

Source—->Preamp—->Amplifier——>Speakers

what is your preamp output, or in the case of an AVR trim level set at.

Next we will ask what is your amplifier input sensitivity, or in the case of an AVR what volume is the dial at?

Thank you all for the help.

I think that you are right. As Mojo said, the M2s are being pushed into their non-linear operating range leading to greater harmonic and intermodulation distortion. When I just keep it to low to medium volume, the busy content still sounds good.

Just want to add one point:

The great clarity of the good quality small bookshelf speakers decreases the volume need to hear everything from the music even in a larger room. A lot of times, you feel that you have to increase the volume to hear the details. With M2V4s, low volume listening could be very satisfied in a quiet environment.

That's right! That's why they work in my 4200 cu ft room at 12 feet away.

Nice job on your observations.

Hey Rock,
You might be asking too much of a specific small box but I imagine there’s one available that will handle the higher volume very well.

Jeff

There maybe another same size bookshelf speaker which could handle higher volume. Hopefully someone has done some side by side comparison and let us know.

My brother has a nice system with B&W floorstanding speakers. I wasn't confident enough to recommend M2 to him until I own a pair. Just ordered one pair as a gift for him and couldn't wait to know how he likes them. Will report his review later.

Nice! Need another brother?

Absolutely, I need another brother and LFR1100 active