Stand Loudspeaker Reviews

Q Acoustics Concept 300 loudspeaker A Sprung Suspension on a Loudspeaker?

Sidebar 1: A Sprung Suspension on a Loudspeaker?

After I attended the launch event for the Q Acoustics Concept 300 with John Atkinson, I found myself interested in this speaker's unique stands—which, as JA points out in his review, incorporate a sprung, low-pass vibration filter to isolate the speaker from its surroundings, much as a suspended turntable isolates the platter from floor-borne vibrations.

It's an interesting idea—especially in the context of a dynamic loudspeaker, which has drivers moving in and out over a wide range of frequencies. When a driver cone moves, its motion imparts a reactive force on the cabinet that holds the drivers (think: Newton's First Law). With rigid spikes, that recoil energy can escape into the floor. A sprung suspension—in contrast to rigid spikes—allows the loudspeaker to move in response to those forces, the motion limited only by its own mass/inertia. Transmission of that energy to the floor isn't possible above the corner frequency of the low-pass filter formed by the speaker's mass and the compliance of the sprung suspension. According to what some Q Acoustics engineers told me, that corner frequency is likely to be around 10Hz.

120q.base

If your floors are made of wood and your loudspeakers have spikes, you may find that your floors make music, too: Turn up the volume and put your ear to the floor. Hear it? That sound is partly transmitted through the air (even so, with rigid spikes, some of that energy could make its way back into the speaker with no isolation), but it is also due to the speaker coupling directly to the floor through the spikes. The floor is now part of your loudspeaker, but not a very good part, as the energy it radiates is delayed and distorted relative to the music the speaker drivers are producing.

What if your floor is made of concrete instead of wood? Then the floor will influence the sound in a different way; as a former resident of a concrete-and-steel condo building, I can attest that concrete can transmit low frequencies exceedingly well, and over long distances.

In other words, with rigid spikes, the floor affects how the speaker sounds in ways that can't be predicted reliably by the speaker designer.

If, instead, you isolate the loudspeaker vibrations from the floor as you would isolate a suspended turntable platter from the surface the turntable sits on—employing a low-pass filter so that higher-frequency vibrations don't pass—then the loudspeaker will behave the same way no matter what kind of floor it sits on.

The following comes from the Q Acoustics engineering team: "Spikes provide a mechanical connection/coupling to the boundary that the speaker is resting on, and the boundary will impart its sound characteristic to the overall sound in the room (and surrounding structures!). With the C300, we chose to isolate the speaker from mechanically coupling to foreign structures, thus controlling/significantly reducing any colorations/delayed sounds that can alter the pure acoustic signature of the speaker."

Two other designers I talked to told me that any reactive motion of the cabinet should be prevented—ie by rigid spikes—lest the cabinet motion smear the sound, especially that coming from the tweeter. Q Acoustics says such matters are managed by using a massive cabinet: That mass imparts considerable inertia, so it doesn't move much. One oft-cited sonic problem with such an approach is smearing of the stereo image—but apparently not here, since JA found the Concept 300's images to be "superbly stable" and "well-defined."

I like the idea of isolating a loudspeaker from supporting structures that will influence its sound in unpredictable ways, but I cannot judge what other effects this will have. Ultimately, whether Q Acoustics' suspension approach is, um, sound is up to your ears to determine.—Jim Austin

COMPANY INFO
Q Acoustics
Stortford Hall Industrial Park
Dunmow Road, Bishop's Stortford, Hertfordshire CN23 5GZ
England, UK
(855) 279-5070
qacoustics.com
ARTICLE CONTENTS

COMMENTS
Ortofan's picture
Submitted by Ortofan on January 3, 2020 - 6:28pm

... bypass or mechanically short-circuit the suspension effect of the stands, particularly if the cables are relatively thick and/or inflexible and especially if the speakers are bi-wired?

For example, the set-up of Linn LP12 turntable requires that the tonearm lead be dressed in a specific manner to prevent the operation of the suspension from being compromised.

Did JA1 make separate sets of frequency response measurements with the port open and with the foam bung installed?

John Atkinson's picture
Submitted by John Atkinson on January 4, 2020 - 4:19am
Ortofan wrote:
How does one avoid having the speaker cables bypass or mechanically short-circuit the suspension effect of the stands, particularly if the cables are relatively thick and/or inflexible and especially if the speakers are bi-wired?

Good question. For the measurements I used very floppy cables, for this very reason. For my listening, I suspended the cables so that they shouldn't have short-circuited the stand's sprung suspension.

Ortofan wrote:
Did JA1 make separate sets of frequency response measurements with the port open and with the foam bung installed?

No, but the bass response with the port blocked can be inferred from the relevant impedance graph, fig.2, which shows that the speaker then behaves as a closed box with a fairly high tuning frequency.

John Atkinson
Technical Editor, Stereophile

Bogolu Haranath's picture
Submitted by Bogolu Haranath on January 5, 2020 - 12:46pm

It is about time JA1 reviews, B&W Formation Duo Wi-Fi speakers ($5,000/pair with stands) and/or KEF LS-50 wireless Nocturnes ($2,500/pair ) :-) .......

Bogolu Haranath's picture
Submitted by Bogolu Haranath on January 4, 2020 - 9:21am

Ortofan needs to take classes in mechanical, electrical and acoustical engineering :-) .......

Bogolu Haranath's picture
Submitted by Bogolu Haranath on January 3, 2020 - 12:24pm

Regarding speaker isolation from vibrations, JCA once mentioned about isoAcoustics isolation devices used in Focal loudspeaker demonstration (Munich 2019) :-) .........

Charles E Flynn's picture
Submitted by Charles E Flynn on January 4, 2020 - 5:19pm

https://www.qacoustics.com/concept-300-bookshelf-speaker-pair-stands.html

Charles E Flynn's picture
Submitted by Charles E Flynn on January 5, 2020 - 11:08am

From https://www.whathifi.com/reviews/q-acoustics-concept-300 :

But while we’re accustomed to a Q Acoustics speaker that favours warmth and refinement over outright liveliness, these fall short of the Dynaudios when it comes to rhythmic drive and dynamic expression. At this level, we would expect more.

Playing Drake’s Headlines, the Dynaudios immediately spring into action with enthusiasm. They hotfoot the synths with a militant timing and almost habitual cohesion that’s missing in the Q Acoustics. The Qs don’t quite hurry things along or grip a rhythm as well as the Dynaudios, which tightly tie everything together like the end of a Sherlock novel. Dynamically, while far from static or uninteresting, they fail to soar and sink to such effective levels, too.

The Concept 300s respond with greater calculation, unrivalled breadth and a textured warmth that fleshes out the midrange, but we find their rivals a more transparent and emotive listen. Ultimately, that seals their four-star fate in this review.

John Atkinson's picture
Submitted by John Atkinson on January 5, 2020 - 2:22pm
Charles E Flynn wrote:
From https://www.whathifi.com/reviews/q-acoustics-concept-300: "But while we’re accustomed to a Q Acoustics speaker that favours warmth and refinement over outright liveliness, these fall short of the Dynaudios when it comes to rhythmic drive and dynamic expression."

I reviewed the Dynaudio Special Forty loudspeaker, which the What HiFi? reviewer preferred to the Q Acoustics Concept 300, in September 2018; see www.stereophile.com/content/dynaudio-special-forty-loudspeaker. Overall, I very much enjoyed my time with the Dynaudios but one thing I couldn't get past with piano recordings was a slight amount of congestion in the midrange.

John Atkinson
Technical Editor, Stereophile

Charles E Flynn's picture
Submitted by Charles E Flynn on January 5, 2020 - 3:19pm

Mr. Atkinson,

Thanks for posting the link to your review of the Dynaudio Special Forty. I suspect few people are as familiar with the sound of both live and recorded piano as you are. I fondly recall the concert in Providence at which you introduced Hyperion Knight.

There are a few copies left of this Knight recording:

https://elusivedisc.com/hyperion-knight-the-magnificent-steinway-cd/

Page 2 of your review of the Dynaudio has this typo: Zeptember

John Atkinson's picture
Submitted by John Atkinson on January 6, 2020 - 4:25am
Charles E Flynn wrote:
Thanks for posting the link to your review of the Dynaudio Special Forty.

You're welcome.

Charles E Flynn wrote:
I suspect few people are as familiar with the sound of both live and recorded piano as you are.

The sound of the solo piano is tough for loudspeakers to reproduce, as there is very little masking in the midrange. If a reviewer doesn't play any piano recordings, he may well miss a problem.

Charles E Flynn wrote:
I fondly recall the concert in Providence at which you introduced Hyperion Knight.

Although I am a big fan of Hyperion's playing, that would have been erstwhile Stereophile contributing editor John Marks.

Charles E Flynn wrote:
Page 2 of your review of the Dynaudio has this typo: Zeptember

Ah, that was a feeble attempt at humor, as I was using a Led Zeppelin recording for a review to appear in the "Zeptember" issue.

John Atkinson
Technical Editor, Stereophile

Charles E Flynn's picture
Submitted by Charles E Flynn on January 6, 2020 - 2:53pm

Mr. Atkinson,

Thank you.

I thought it was possible that the "Zeptember" was deliberate, but then I did not recall any other examples of such an attempt at humor.

I hope I am never called to give eyewitness testimony about who was present at a concert.

Pianist Hyperion Knight to Perform in Providence RI February 25, 2018

https://positive-feedback.com/audio-discourse/pianist-hyperion-knight/

02-05-2018 | By John Marks | Issue 95

You make a good point about the value of piano recordings for evaluating speakers. I will try to remember that better than I remembered who introduced Hyperion Knight.

Bogolu Haranath's picture
Submitted by Bogolu Haranath on January 5, 2020 - 12:27pm

$5k is somewhat expensive for a 2-way passive bookshelf speakers ........ There are several 2-way bookshelf speakers listed in Class-A and Class-B in Stereophile recommended components, some of which costing less than half the price of Q300 ......... For $5k one can get any of those bookshelf speakers plus two powered subwoofers ........ B&W Formation Duo Wi-Fi capable speakers are $5k with stands, BTW :-) .........

tonykaz's picture
Submitted by tonykaz on January 6, 2020 - 3:46pm

and assessment ?

Should we consider a Pair of Devialet Phantom 900s for about $3,500 ( made in France ) : a Stunning Music System.

Why would we consider a pair of spindly Mini-Monitors ( Asia Made ) costing $5,000 ?

I can't help noticing that these tiny things need Higher Authority comparisons from Wilson & Magico, etc. ( betcha these outfits aren't happy to be favorably compared like this, I wouldn't ).

So, I beg to ask: How can a technical outfit like Devialet produce 21st Century Electronic Transducer Devices ( in France ) and still charge considerably less. Why would Brit. Engineers source in Asia?

Something smells >)))))'>

Tony in Iowa frrrrreeeeezzzzzzzzzzz'n

ps. should we now expect our LS3/5a to be made in China ? What tragedy is befalling our Island friends?

ps. I know people spending serious money for Isly Single Malt that favorably compares to horrible ( my, not useful, opinion )

Bogolu Haranath's picture
Submitted by Bogolu Haranath on January 7, 2020 - 10:25am

I'm waiting for Asian made Scotch whisky for $5 a gallon :-) .........

tonykaz's picture
Submitted by tonykaz on January 7, 2020 - 4:11pm

How can Scotch be made in Asia?, isn't it Scotch from being made in Scotland???

Tony lost in the fruited planes

Bogolu Haranath's picture
Submitted by Bogolu Haranath on January 7, 2020 - 4:23pm

(Recipe) designed in Scotland, made and bottled in Asia ....... That is a good possibility ..... BTW, they are now making Tesla cars in Shanghai :-) .......

Bogolu Haranath's picture
Submitted by Bogolu Haranath on January 7, 2020 - 4:26pm

What is a 'fruited plane'? :-) .......

tonykaz's picture
Submitted by tonykaz on January 7, 2020 - 7:13pm

The great Mid-West was described as a "Fruited Plane" by the 1850s emigrants ( whilst still in the Old-Country ) prior to making a decision to immigrate and inhabit places like Kansas and Iowa where Land was deeded ( for free ) as an inducement to Build America into a White Man's Paradise.

Of course, the Native Indigenous population were escorted/forced out & down the "Trail of Tears" to their New Mexico Homes ( reservations ).

My ancestors were part of the 1850s group of Europeans that traversed the Erie canal to claim their Acreage recently vacated by the Native Indians, they then prepared to fight the Civil War to right the wrongs of Slavery.

The Fruited Plane is that vast track of land now known as America's Bread Basket : Flat Farm Land West of the Mississippi River where the Buffalo roam and Grasslands became Wheat Fields and Kellogg Cereals .

Tony hoping to return to Venice

Bogolu Haranath's picture
Submitted by Bogolu Haranath on January 8, 2020 - 6:36am

The spelling may be 'Fruited Plains' (grassland, flatland) ........ Google search :-) ........

tonykaz's picture
Submitted by tonykaz on January 8, 2020 - 8:47am

Yes, not hard to agree with you, thanks. I sit, corrected ( stand ).

Its a dam cold place.

But...

If they were giving me a homestead of free acreage I'd probably accept too.

A curious thing is that these folks are identical to everyone I've ever met anywhere in the World, they seem to want the same things and even look pretty much the same. I might've thought that they'd look like Hee-Haw TV Show Farmers, they don't, they could easily look like people walking down the street in San Fransisco or anywhere else.

I'm looking forward to the Deep South Campaign tour. I've heard that those people look the same too. Everyone seems kinda wonderful, I wasn't expecting that. ( being from angry-finger waving Michigan )

Tony out in the cold

Bogolu Haranath's picture
Submitted by Bogolu Haranath on January 8, 2020 - 9:07am

In one of the recent polls, Iowa was ranked as the number one ideal state to retire ........ Florida was ranked as one of the top ten states :-) .........

tonykaz's picture
Submitted by tonykaz on January 8, 2020 - 10:38am

Hmm, kinda illustrates the problem with Polling Data or suggests the Poll was hired by the Iowa Real estate developers association.

Of course, if a person likes vast panoramas of windy flowing grasslands or has a group-home overlooking the John Deere Combines at harvest time, this place could be a peaceful home.

then again,

who can retire now-a-days? or afford to retire ? Siemens abandonded Iowa workers for the Czech republic and a non-union workforce.

Tony out somewhere

Bogolu Haranath's picture
Submitted by Bogolu Haranath on January 8, 2020 - 10:35am

Another poll shows, Nebraska as the number one state and Iowa as number two ideal state to retire ....... New York State and California are at the bottom of the list ....... Not surprising :-) .......

soundcents's picture
Submitted by soundcents on January 9, 2020 - 2:17pm

The the Trail of Tears refers to the forced removal of native peoples as a result of Andrew Jackson's "Indian Removal Act" of 1830 (ending in 1850). Although many of the groups were marched through the mid-west on their way to "Indian Territories" (modern day Oklahoma) the groups were actually from the south east. The Chickasaw, Choctaw, Creek, Seminole, and Cherokee people were marched from modern day Mississippi, Alabama, Georgia and Florida.
The trail of tears was over 5,000 miles long, resulted in the death of more than 16,000 native people and the loss of 22 million acres of their land. The name refers to a quote from a Choctaw leader who referred to the forced marches and relocation as a "Trail of Tears and Death"

tonykaz's picture
Submitted by tonykaz on January 7, 2020 - 4:11pm

How can Scotch be made in Asia?, isn't it Scotch from being made in Scotland???

Tony lost in the fruited planes

Ortofan's picture
Submitted by Ortofan on January 7, 2020 - 10:16am

... Hong Kong?
https://6moons.com/audioreviews2/rogers/1.html

Want to consider an even less expensive speaker?
Try the KEF R3:
https://www.youtube.com/watch?v=5esoOMgzfUo

tonykaz's picture
Submitted by tonykaz on January 7, 2020 - 4:14pm

Ouch, this one hurts.

Tony out in the freezing winds

Anton's picture
Submitted by Anton on January 7, 2020 - 2:45pm

After the review of the Crystal Cable Arabesque Minissimo Diamond speakers, I expect these to have a "$$$" next to their name in the next Recommended Components.

Four pairs of these = one pair of the Crystal Cable.

Jack L's picture
Submitted by Jack L on January 12, 2020 - 3:53pm

...... structures that will influence its sound in unpredictable ways,.." quoted Jim Austin.

Yes, that's why I have my KEF 2-way standspeakers isolated from their spiked steel tubular tripods (full stuffed with lead shots & baked fine fine sand to increase their mass) with 4 dense cushion pads each. This should reduce substantially any loudspeaker box vibration from passing down on to the concrete floor underneath through the tripod spikes.

It sounds obviously cleaner to my ears than without.

listening is believing

Jack L
Canada

Charles E Flynn's picture
Submitted by Charles E Flynn on February 13, 2020 - 5:06pm

It is always interesting to see what products covered in specialized Websites manage to gain the attention of Websites geared to a wider audience:

https://gearpatrol.com/2020/02/12/best-bookshelf-speakers

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