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Author: Mark Wheeler - TNT UK
Published: May, 2024

Walls and Floors

When house hunting with one's beloved (person or pet) there are things to watch out for.

Quite apart from settlement cracks in the masonry or dry-rot and death watch beetle in the woodwork there are hifi considerations. Is there a fast enough broadband connection for high-quality streaming? Is there a solid floor potential listening room? Are there solid masonry (brick, stone, insulation blocks) walls in the potential listening room?

For turntable users at least one of the two (and preferably both), solid floors and solid walls, must be Essential attributes to a house purchase, whatever other Desirable attributes any potential home may have. The listening room above had lime plaster over stone walls where the turntable attached and a 300mm thick cast thermal mass floor under 11mm quarry tiles. That room above transpired to be an excellent audio room despite not looking ideal if online articles are to be believed.

It is quite possible to isolate, with flexible materials, loudspeakers from resonant floors. The spikes with everything myth really is another myth that came about by generalising from a handful of cases. Firstly spikes do not decouple. Spikes couple really effectively by concentrating extremely high pressure onto a tiny area.

Here are some relevant thoughts about domestic acoustics. From here on in we're thinking solely about room construction and turntable support.

Turntable support and room construction

Sweeping generalisations are always wrong.

Before the Plebs Chorus interrupts from stage left, that paradoxical statement is there to wake them up. The problem with most audio set-up articles is that they generalise from the specific and that just will not do. Readers are often reading because we want certainty. We want to know that A is definitely superior in every way to B. Sadly A is rarely better than B in more than 50% of circumstances because context is everything. We have to learn to tolerate uncertainty.

Having written that statement, in most cases, most of what is written below is mostly true most of the time, in your Old Scribe's experience.

This Odyssey began when your Old Scribe discovered in 1985 that a newly purchased Linn Sondek LP12/Ittok/Karma was extraordinarily sensitive to what it was on. I hadn't really noticed this tendency with my previous Thorens TD125/SME and TD150/SME. These now belonged to friends, so all 3 were gathered together to check. It transpired that all 3 were affected by their supports. Who knew? Eventually an Apollo wall shelf was bought after specialist floor stands failed the dancing guests test. That Apollo wall shelf taught your Old Scribe the 3 points good - 4 points bad lesson, with its little steel spike discs on all 4 corners chattering away and causing certain frequencies to be prominent. Then a house move prompted a fresh round of experiments.

Wall shelf vs floor stand

A wide range of different approaches to wall shelf and floor stands for turntables were tried with that Linn while it also acquired the requisite Linn upgrades that seemed to arrive every year. The best floor stand transpired to be the Something Solid XR4 rack and the best wall shelf was the Origin Live Skyline Ultra with the Linn converted to a single central hard foot in place of the 2 rear instrument feet. Where there are equally solid walls and floors the comparisons are valid. As soon as either wall shelf or floor type changes, the case is altered. The now long obsolete Origin Live Skyline Ultra wall frame and the Something Solid XR4 transpired to be the best of the wall and floor turntable supports respectively. The Origin Live Skyline Ultra does outperform the Something Solid XR4 rack in the equally solid wall and floor context because...

“Because wall shelves always outperform floor standing racks under sprung subchassis turntables?” Interject Plebs, stage left

Indeed, because all other things being equal, this is invariably the case. Despite the comics of the 80s and 90s insisting that “Light rigid tables are the best support for the Linn Sondek [and similar]”, this is far from the truth. Indeed this is often the opposite of the truth. The only time the hi-fi magazine turntable support myth has any credibility is in a house with solid cast concrete floors and stud partition plasterboard walls. This is a very common modern cheap construction type in the UK which may have led to this myth. The Origin Live Skyline Ultra only works with sprung subchassis turntables with perfect vertical bounce and no other suspension modifications like spokes or tie threads.

In a house with suspended (i.e. boards on joists) wooden floor, typical of older British houses, the floor may be the worst place for a turntable support. If the walls are plastered brick or breeze blocks or insulation blocks the wall shelf will be better than whatever floor there is and extremely, audible from the next room, better than a suspended wooden floor. The only mitigation for a wooden floor under a turntable stand is if the joists immediately below the stand are directly securely attached to a concrete subfloor below.

If the walls are plasterboard and the floor is suspended timber floorboards, there are three main possibilities. The first is to remove the suspended timber floor and cast a concrete slab...

“Which can then be a thermal mass with underfloor heating, removing the need for resonant radiators and improving eco sustainability,” Offer more environmentally aware Plebs, stage left

Indeed. Or removing a section of the floor and casting a concrete pillar for the area under the turntable stand. Or thirdly, attaching some steel struts between the nearest floor joist and the subfloor.

“Or just buy a wall shelf,” Suggest more pragmatic Plebs, stage left

Which will not work with stud and plasterboard walls at all but will be ideal with turntable specific wall shelves. Hollow plasterboard and anything similar are probably the reason for the myth that claims floor stands are ever better than wall shelves under suspended chassis turntables. Walls made from bricks, insulation blocks or other blockwork will outperform floor stands because there is less physical connection from the loudspeakers. An additional factor is that sand based mortars (especially if limed e.g. 6:1:1) will perform a similar function to a sand box or sand filled turntable plinth. For solid plinth turntables or subchassis turntables with alternatives to coil springs (e.g. o-rings, leaf-springs, sorbothane blocks, compliant mushrooms etc.) each individual design in each house context will work differently, of which more in a later article.

Following the front end first principle, advocated by Linn throughout the Sondek history, it is possible to argue that the stability of the turntable support is the actual front end. The stability of the turntable platform depends on the mechanical integrity of the room construction. Coupling the turntable to the loudspeakers via a wooden floor is one of the worst case scenarios. Attaching the turntable to highly resonant thin membrane cavities in a plasterboard wall is also a problem. It is possible to mitigate these hollow walls with large sheets of rigid material that cover (and are attached to) several joists but even this is less effective than a good masonry wall. It is possible to mitigate a floor stand by rigidly attaching the top of the stand to a masonry wall but this will be inferior to a proper turntable shelf attached to that wall.

Conclusion(s)

For optimum performance our subchassis turntables need to be held in space with stability. For the coil sprung bounce to do its work effectively the turntable needs a suitable shelf. While many music lovers happily accept compromises in room layout and achieve results they find acceptable, it is your Old Scribe's experience with many houses and many systems that coil-sprung subchassis turntables need concrete, brick, blockwork or stone for at least one wall or the floor in the listening room.

Happy house hunting or house building!

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