Axiom Home Page Forums General Discussion Advice from Axiom Owners Bookshelf or FloorStanding 5.1 System vs. Room Siz

I want to build a 5.1 surround sound system. The main speakers would be a 3-way rather than two-way design for the performance reasons cited in the video here. https://www.axiomaudio.com/m5-bookshelf-speakers

The 5-channel Class AB power amp https://www.crutchfield.com/S-4qWPQyxK7XD/p_313A52PB/Parasound-Halo-A-52.html https://www.stereophile.com/content/music-round-91-parasound-halo-52-page-2 driving those five speakers will feed the unbalanced inputs of a multichannel DAC like this one. https://www.exasound.com/Products/e688-channelDAC.aspx

And the DAC’s balanced inputs would be fed by two pairs of these powered subs https://jamesromeyn.com/speakers/subwoofers/ak-tall-subs/ or two pairs of these powered subs. https://www.rythmikaudio.com/F12SE.html

A standalone or software assisted DSP solution for bass management and room correction will be added later.

Presumably, the problem of classifying the “acoustically relevant” size of my listening room is that its basic dimensions spill over and extend into other rooms. And because it does so-and because there’s probably little that I can do to acoustically correct for this-how much will negatively impact sound quality?

My Listening Room

Width: 11 feet. But it then extends across a ~3.5 ft wide hallway, and which is ~ 14 feet long where the three doors can be closed there.

Then one foot past that hallway my listening room then empties into the kitchen that extends the total width by another 8 ft. And the kitchen length is ~ 10 ft. Then immediately past the kitchen wall the room’s width crosses past a 4 ft. wide L-shaped downstairs staircase, which extends my room’s 11-foot room width by another 11 feet, before turning to go further downstairs.

Windows. My room has three bay windows all on one wall which I usually keep closed and draped.

Length: Just under 20 ft.

Height: Triangular ceiling. Apex 11 ft that declines to 8 ft.

Therefore, given my room’s “effective size” and acoustical environment should I choose five 3-way bookshelf speakers, each placed on a ~20” high platform on the floor?

Or some combination of 3-way bookshelf and 3-way floor standing speakers?

Look at how "challenging" my friend's space is. Cathedral ceiling like yours. She thanks me every day for her walnut natural satin M5s, driven by my 20 year-old Denon and $99 Sony sub. The M5s are poised on $5, 10" high stands from IKEA.

There are no M5s to be heard. Just tall, deep, wide soundstage behind and beside them with solid images performing on that stage. With the right recordings, like Madonna's Vogue, the entire room is ablaze with prancing images.

She has no trouble rocking throughout her 4-story home!

You do not need floor-standing and on-wall would work great to de-clutter your space.

These are M2OW flanking my 10' bow window. I've also used M5OW in that location but found the bass over-powered my 22' x 12' living room which is open to the rest of the house. Wide, tall, and deep soundstage from both the M2 and M5. When I say deep, it's out the front window. And wide means 22'.

This is all very encouraging. Thanks! Except for acoustical materials, I dislike mounting speakers or any hardware on walls. But one big worry I always had with stand speakers as opposed to floor standing ones is knocking them over. I live alone. Your friend obviously has no such anxieties. But how about this for a fix: A solid wooden box under each speaker that overshoots their footprints by ~ 6". Then folding over a few ~ 20" lengths of 2" wide gaffers tape to form doubles-sided adhesive strips to affix the bottom of each speaker to its wooden box stand. Yes?

The solid box idea might be OK on carpet. A wood floor may resonate particularly since the box would form an acoustically resonant cavity. At my friend's, I mounted little rubbers under the M5 and the stand's legs in an attempt to de-couple from the floor. Works well!

The M60 may be a better bet but I can't say whether it would acoustically disappear as well as the M5.

BTW, I can tell you are the type who would NEVER knock over his speakers. So don't worry about it.

Well, except for the fact that I'm the king of bad luck, so I always err on the side of caution.

My flooring is carpeted. But it would certainly help knowing how speakers like the M5HP would sound crossed with two pairs of subs. And would I'd still be better off with M60 or M80? Any thoughts on this?

The M80s will play louder than the M5s. But you may find positioning them in the room is a challenge and you may not be able to get them to acoustically disappear.

With that amp and subs, I can't see a benefit with M60s. M60s may be a detriment actually for the same reasons as M80s.

The M5s would sound terrific with as many subs as you want. I've used them with up to 7 subs. Fantastic!

The M5s are far less prone to position error than the larger Axioms. They are as refined as the M100 and active LFR and far easier to succeed with quickly.

Open floor plans should be treated as a single volume, but since you're sitting closer to the loudspeakers within that volume, you don't necessarily have to upsize all the audio components. But if you like it loud, err on the side of more power and bigger speakers.

And Mojo, I'm detecting blank spots on the wall awaiting the next candidate weapon. May I suggest:

https://www.amazon.ca/GURPS-Ultra-Tech-David-L-Pulver/dp/1556349718

(I somehow have the first edition written 30 years ago, sitting with some of my Mike Pondsmith RPG's).

As my hearing is almost as good as it ever was, I would approximate that at ~ 6 feet no more, if not less than 45db SPL @1kHz, 53db @ ~ 8kHz, 65db @ 100Hz, and so on, below which my subs would take over.
https://en.wikipedia.org/wiki/Equal-loudness_contour

That speakers can achieve absence of their audible presence is certainly a good thing, especially if this happens along with a spacious soundstage and other characteristics that create and transport the listener to realistic sonic realm. That's why I've always found Enjoy the Music's performance check list extremely useful for evaluating hardware. See the bottom of this page. https://www.enjoythemusic.com/magazine/equipment/0214/axiom_audio_m100.htm

Without speaker acoustic disappearance, the illusion falls apart.

That review is for the M100v3. The v4 has the OMG! tweeter and multiple other improvements to the M100's polar response curves.

With regard to the scorecard, you might get more intelligence from what the reviewer did and did not write.

One tip regarding the M5: experiment with stand height before committing to a design or purchase. I, and at least two others on this board, have found dropping the tweeters at least 6" below the ears results in holographic soundstage and imaging with no speakers to be heard.

One more thing: there are members on this board who have made their M80s and M100s disappear even though I could not.

Hambrabi, there is no excitement in dispatching the evil dead with high tech weapons.

Yes, the two up top are combat-ready Shanghai double daggers.

That review of the M100 makes me cringe. B.S. words like air, attack, decay, inner resolution, and tonality are really just words for frequency response, and the rest is about the acoustic environment of the room.

A straight listening window and a gently sloping sound power directivity index is a good enough toolkit for most of us to separate the wheat from the chaff, and (the impossible to find) frequency response at 85 db, 95 dB, and 105 dB should also be enough to determine whether it will fill a room with sound.

Speaker reviews don't need to be more than 500 words, and half of that can be about the manufacturer, model line up, placement against competitors, sensitivity/efficiency, and feature set. If it's more than 500 words, it is written for entertainment and commerce, not for the consumer.

The holy hosannas I heard out of the M100s were large, realistic, with cherubs nicely rendered in a tall, wide, deep sound field. Unfortunately, I could see the cherubs exiting from the M100s.

With the M5, the hosannas were smaller, less real, with the cherubs appearing from dark singularities forming in a holographic soundfield behind, to the side, above and forward of the M5s.

One setup I’ve always fantasized about and might be an option in this case….

M5Hp with dual ep500 or ep600 as the stands for the m5s. Select 500 for lower tweeter height or 600 for higher tweeter height.m relative to your MLP ear height. Apply some manufactured or homegrown decoupling to the bottom of m5 and against floor at base of the subs too, as mojo described above and voila. Crossover the m5 to the subs and relieve the m5 of low frequency duty reducing distortion and improving godly holographics.

Why have wooden boxes that could resonate when you could have stereo subs the bring true offerings to the sanctuary. Baptize those hosannas!

This would of course be in addition to your Rythmik subs. Apply proper dynamic high wattage overhead amplification and you’re set.

This setup alone could open a singularity. Use the volume knob to adjust the aperture size. If you’re not careful it may swallow your whole house. Like pulling your lip up over your head and swallowing an event horizon.

All kidding aside, it would kind of like be like having a 4 way speaker that is tuneable. I’m sure this idea is fraught with problems or acoustic malcontents perhaps.

Another thought in line with Hambrabi, I agree with thinking of open space as one volume of cubic space. I think that is good advice. Play with room acoustics and basic treatments. As I’ve been learning in my large open space, adding mass to the space helps and soft cushy things helps too such as thick carpets and underlay, cushions couches furniture etc. The room can always be improved.

Cool theatre plan and thoughts you have. Looking forward to seeing what you do end up going with.

Tyler, you may want to try building diffusers.

Totally. I’m doing the research and sifting through all the BS that is out there. We are looking at doing our great room this spring.

-Wood stove and hearth. ( we miss that alot from our old place )

-Paint

-Tongue and groove ceiling. ( could incorporate treatments up there as per Trevor, haven’t seen him around the forum in awhile. )

-Wood “ waynescotting” on walls up to 4/5 feet to compliment the hearth. Could incorporate treatments there as well.

-Id consider some decoupling and isolation for the towers too and the sub ( or subs after I get another ).

The heavy carpet and underlay was a tangible damping. As was adding a big recliner.

I feel like our floors are “excitable” a bit too. So looking for options to tame that as well. But that’s fully conjecture at this point.

I’m reasonably handy and have all the tools for lots of things so building treatments is totally possible. Open to suggestions.

I love all those ideas. I'll give you a suggestion. How about you adopt me and I'll help you figure it all out.

Sure. You’re in. Bring scotch, I’ll toss all the apple juice out with the children.

I don't drink. But I'll sniff and snort your scotch and live vicariously through you after you scarf it down. I like kids. And they like me.

I have room about same size. My Anthem 720 and M5HP and VP106HP are very efficient . I have a SVS 2000 Pro sub. I like that I can position the Bookshelves better and height wise to for clear soundstage and presence. they totally disappear. wish I could upload new pics though

The disappearing of the M5s is certainly a beautiful thing. Too damned bad they need more than 4 times the power of an active LFR to achieve the same SPL as an ALFR!

Troy, you can upload images using https://postimages.org/.

For another data point here's my layout: https://drive.google.com/file/d/1o7ZU0ZxGuO5gu96gLmHStV1uq4nR3M8P/view?usp=share_link

I have M80s in the location labeled 'speakers'. They are probably more than I needed but are not too much. (M60s would have been fine, Mojo was right; but dammit, I wanted M80s!) I'm using the Axiom ADA1000 and turn it up to about 1/3 to listen at about 80-85 db. There a longer than normal wire run (far corner of the room on the top-right), so that might be sucking up some juice.

That same top-right room has M5s and I find them a tad weak; but I'm only driving them with a Yamaha RX-V671, with a better amp they'd be fine. The M5's are unnecessary for my study (not shown) which is 13'x14'. But they're not too much either.

As for towers tipping over, I've not had a problem and I have to klutzy 60 lb dog and a schizoid cat that tries to jump on top on anything and everything. Axiom also sells outriggers if you want even more stabilization.
https://www.axiomaudio.com/outriggers-set

So to parrot the other opinions, you'd be fine with either M5 or M60s, it would just depend on your layout options and preference.

M2s with a 350 would have been fine in my space but dammit...I wanted active LFRs with 7 sealed subs!

Cork, I'm surprised you're still alive! I guess you didn't touch the chairs or the embalmed monkey?

377 Ohms

Toe it in, toe it out
Let the wife scream and shout
Slide those chairs all around
watch her howl like a hound.

Those god-damned pictures have to go
The monkey ju ju also so
Ju ju, pictures, firepit
Watch her throw a hissy fit.

Speakers pounding out the sound
Images forming all around
Cork just laughs hysterically
As soundstage expands majestically.

The ol' lady screeching, bloody freaking
As her bones start a creakin'
Bones that jump right through her skin
Erasing Cork's shitty grin

Ulna shoved up Cork's rectum
Tibia deviates his nasal septum
Her patella rips his scrotum
Cork is propped up like a totem

Her skull holes are alit with anger
As she grabs a wire hanger
Gouging woofers, squawkers, tweets
Cackling now Cork's heart she eats.

Cork's spirit now starts to rise
A peaceful look deep in his eyes
For in the light, across the gates
A majestic sight awaits.

He sees a place in the light
Filled with speakers, amps with might
Best of all but could it be?
Not a boundary to infinity.

The monkeys don't frighten me (embalmed, flying, or otherwise); but touching those chairs ... <shivers>

I have the poem copied off, I've been waiting for the right time to frame and hang it next to my speakers. That time generally comes when she's already good and annoyed at me, because I like to double down. I even bought fake antiqued paper. (BTW, my version attributes 'Mojo'.)

You just made my month!

BTW, you understand the reference to 377 Ohms?

I did not, and I was too embarrassed to ask.
But this time I googled it, and came up with this: https://en.wikipedia.org/wiki/Impedance_of_free_space - which is both fun to know and an awesome title!

Yup. I don't know if it's awesome or scary the abstractions humans make to describe a world they will never have direct access to.