XSCACE · Reference

Architectural audio,
term by term.

The vocabulary of architectural speakers — what each specification actually measures, why it matters when you are specifying a system, and where the numbers on a data sheet can mislead. Written for architects, interior designers and AV integrators.

35 terms · 4 categories

Speaker Types & Mounting

How a speaker physically meets the architecture — the vocabulary specifiers use on drawings.

Architectural speaker

A speaker designed to be built into the building rather than placed in the room.

An architectural speaker is installed into a wall, ceiling, or millwork so that little or nothing protrudes into the room. The category covers in-ceiling, in-wall, slim-array and on-wall products. The defining constraint is that the enclosure volume is limited by the building cavity, not chosen freely by the designer — which is why depth, sensitivity and bass extension are always in tension.

XSCACE architectural speakers range from 12mm deep (Bonsai) to 135.9mm (Oak).

In-ceiling speaker

A speaker mounted into the ceiling plane, firing downward.

In-ceiling speakers sit above the ceiling line and radiate down into the room. They give the most even coverage for background and multi-room audio because sound arrives from above rather than from one wall, but they are less suited to critical stereo imaging, where the soundstage should sit at ear level in front of the listener.

Aspen 6 needs 107.95mm of ceiling depth; Ghost 2.0 needs 187.96mm.

In-wall speaker

A speaker mounted into the wall plane, firing horizontally into the room.

In-wall speakers fire across the room at or near ear height, which makes them the correct choice for left/right/centre channels in a cinema or a stereo listening room. They depend on available stud-cavity depth, which in standard construction is often the binding constraint.

Willow requires 110mm of wall depth; the Cane In-Wall requires 24mm.

Slim-array speaker

A shallow speaker using several small drivers instead of one large one.

A slim-array uses multiple small drivers in a vertical line rather than a single larger cone. Distributing cone area across several drivers recovers output and sensitivity that a single small driver at the same depth could not reach, which is how a very shallow enclosure can still play at usable levels. The trade-off is bass extension, since low frequencies need enclosure volume regardless of driver count.

QuadCane uses 16 drivers in 21mm of depth to reach 95dB sensitivity.

Landscape (rock) speaker

An outdoor speaker built into a rock-shaped enclosure for garden placement.

Landscape speakers solve the problem that gardens rarely have a wall where sound is needed. Built into a rock-form housing, they sit directly in planting beds or lawns away from the building. They require their own buried cable run, which is usually the deciding cost factor rather than the speaker itself.

Spirea is IP66-rated for permanent, fully exposed outdoor placement.

Mounting depth

The cavity depth a speaker needs behind the finished surface.

Mounting depth is the single most common reason a specified speaker cannot be installed. It must be checked against the real cavity — after allowing for services, insulation, fire barriers and structural members — not against the nominal stud or joist size. A 90mm stud wall does not offer 90mm of usable speaker depth.

Bonsai needs 12mm, which fits surfaces no conventional speaker can use.

Cutout dimensions

The hole cut in the wall or ceiling to receive the speaker.

Cutout dimensions differ from the speaker's outer bezel dimensions — the bezel overlaps the cut edge to hide it. Cutting to the bezel size rather than the cutout size is an unrecoverable error on a finished ceiling, so templates are supplied for exactly this reason.

Back box

A rear enclosure fitted behind an architectural speaker.

A back box gives the driver a controlled, sealed volume instead of letting it radiate into the open building cavity. It improves bass consistency, reduces sound transmission into adjacent rooms, and is sometimes required for fire or acoustic compliance. Without one, the cavity itself becomes an uncontrolled and unpredictable enclosure.

Flush mount

An installation where the speaker face sits level with the finished surface.

Flush mounting leaves the grille level with the plaster or panel line rather than proud of it. Combined with a paintable grille, it is what allows a speaker to visually disappear. It requires the cutout depth and the finish build-up to be coordinated before the surface is finished.

Paintable grille

A grille designed to be finished in the room colour.

A paintable grille can be sprayed to match the surrounding surface. The critical constraint is that paint must not bridge or clog the perforations — heavy roller application audibly dulls the top end, whereas a light spray coat does not.

Rough-in

First-fix stage, when cabling and brackets are installed before surfaces close.

Rough-in is the point at which speaker positions become effectively permanent. Cable is pulled and mounting hardware fixed before plasterboard, plaster and decoration. Audio decisions deferred past rough-in usually become either compromises or rework.

Acoustic Specifications

The numbers on a spec sheet that describe how a speaker actually behaves.

Frequency response

The range of pitches a speaker reproduces, with a tolerance figure.

Frequency response is quoted as a range in hertz with a tolerance, such as 150Hz–20kHz ±3dB. The tolerance is the meaningful part: without it, a manufacturer can claim a very wide range by including frequencies the speaker reproduces only very quietly. A narrower range quoted at ±3dB is a stronger claim than a wider range quoted with no tolerance at all.

Cane covers 150Hz–20kHz ±3dB; Oak reaches down to 40Hz.

Sensitivity (dB)

How loud a speaker plays for a given amount of amplifier power.

Sensitivity is measured in decibels at one watt at one metre. It is a measure of efficiency, not of quality or maximum volume. Each 3dB of additional sensitivity is roughly equivalent to doubling amplifier power, so a 96dB speaker reaches the same level as an 86dB speaker on around one tenth of the power. In large or open spaces, sensitivity often matters more than raw wattage.

Cedar is 96dB; Bonsai is 86dB — a ten-fold difference in power demand.

SPL (sound pressure level)

The actual loudness produced at a listening position.

SPL is measured in decibels and describes real loudness in the room, as opposed to sensitivity, which describes efficiency. SPL falls with distance — roughly 6dB for each doubling of distance in free space — which is why open terraces and large rooms need more capable speakers than their floor area alone would suggest.

Crossover

The filter network that splits audio between drivers.

A crossover routes high frequencies to tweeters and low frequencies to woofers, so each driver only handles the band it can reproduce well. Component quality and tolerance at the crossover point materially affect how coherent a speaker sounds, which is why it is one of the least visible and most consequential parts of a design.

Crossover frequency

The hand-off point between a speaker and a subwoofer.

The crossover frequency is where bass duties transfer to the subwoofer. It should be set at or slightly above the speaker's usable low limit, not below it, or a band of frequencies is reproduced weakly by both or by neither. Speakers with a higher low-frequency limit depend proportionally more on the subwoofer being set correctly.

Bonsai stops at 300Hz, so its subwoofer carries far more of the range than usual.

Dispersion (directivity)

How widely a speaker spreads sound horizontally and vertically.

Dispersion determines how many seats hear a consistent tonal balance. Wide dispersion suits social spaces where people move around; narrower, more controlled dispersion suits a fixed listening position and reduces unwanted reflections off side walls.

RT60 (reverberation time)

How long sound takes to decay by 60dB in a room.

RT60 is the standard measure of how reverberant a space is. Hard surfaces — marble, glass, stone — raise it and reduce speech clarity; soft furnishing, rugs and fabric panels lower it. Because RT60 is a property of the room rather than the speaker, measuring it on site is what turns a predicted system design into a verified one.

Room modes

Bass peaks and nulls caused by the room's dimensions.

Room modes are standing waves created by parallel surfaces, producing positions where bass is exaggerated and others where it nearly disappears. They are a function of room geometry, so they cannot be fixed by buying a better subwoofer — only by placement, multiple subwoofers, or equalisation.

Hoffman's Iron Law

You can optimise two of three: bass extension, efficiency, enclosure size.

Hoffman's Iron Law states that low-frequency extension, sensitivity and box volume are mutually constrained — improving two necessarily worsens the third. It is the reason very shallow architectural speakers must either give up bass extension or give up efficiency, and why any claim to have achieved all three at once deserves scrutiny.

Thermal compression

Loss of output as a voice coil heats up during sustained playback.

As a voice coil heats, its electrical resistance rises and it converts less power into sound. The audible result is that a speaker becomes progressively duller and quieter the longer it is driven hard. Chassis materials that conduct heat away from the coil reduce the effect, which matters more in commercial installations running long service hours than in intermittent home use.

THD+N

Total harmonic distortion plus noise — unwanted content added to the signal.

THD+N expresses, as a percentage, how much of the output was not present in the original signal. Lower is better. The figure is only comparable between products when quoted at the same power level and frequency, which manufacturers do not always state.

Power & Electronics

How speakers are driven, and how to size the equipment behind them.

Impedance (ohms)

The electrical load a speaker presents to the amplifier.

Impedance, measured in ohms, determines how much current a speaker draws. A 4-ohm speaker draws roughly twice the current of an 8-ohm speaker at the same voltage, so it requires an amplifier explicitly rated for 4-ohm operation. Spare wattage on an 8-ohm-only amplifier is not a substitute — this is a common and damaging specification error.

Cedar and Oak are 4Ω; Cane, Bonsai and QuadCane are 8Ω.

RMS power vs peak power

Continuous power handling versus brief maximum handling.

RMS is the power a speaker can handle continuously and is the figure to design around. Peak describes short transients only. Because peak numbers are larger and less rigorously defined, they are the figure most often used in marketing — comparing one product's peak against another's RMS is not a like-for-like comparison.

Cane is rated 50W RMS and 60W peak.

Passive speaker

A speaker with no built-in amplifier, driven from an external amp.

Passive speakers contain drivers and a crossover but no amplification, so they need an external amplifier channel and speaker cable. Almost all architectural speakers are passive, which keeps electronics accessible in a rack rather than buried in a ceiling where they cannot be serviced or cooled.

Powered (active) speaker

A speaker or subwoofer with amplification built in.

A powered product contains its own amplifier and needs mains power at its location rather than an amplifier channel. This is common for subwoofers, where the amplifier can be matched precisely to the driver, but it means the electronics live wherever the product does.

Acacia 10 is available in both powered and passive versions.

DSP (digital signal processing)

Digital correction of level, delay, crossover and equalisation.

DSP applies filters, time delay and equalisation in the digital domain before amplification. It can compensate for unequal speaker distances, correct predictable room behaviour, and protect drivers. It cannot fix an acoustically unsuitable room or a speaker placed in the wrong position — it corrects the signal, not the physics.

Amplifier channel

One independent amplified output feeding one speaker.

Each speaker in a stereo pair normally needs its own channel, so a room usually consumes two. Channel count must be planned against room and zone count before cabling, because under-provisioning forces rooms to share zones that should have been independent.

Lucifer 8 provides eight channels — four stereo pairs.

Zone

A group of speakers under one independent volume and source control.

A zone is the smallest area that can be controlled separately. Rooms with genuinely different uses should be separate zones — a gym and a bedroom sharing one zone means one of them is always at the wrong volume, and this cannot be corrected after cabling without rework.

70V / 100V line

A distributed audio system for long runs and many speakers.

Constant-voltage (70V or 100V) systems use transformers so that many speakers can run from one amplifier over long cable distances without impedance problems. They are standard in large commercial installations, and are generally not used in high-fidelity residential work, where low-impedance wiring gives better quality.

Ratings & Standards

Formal ratings that determine where a product may legitimately be installed.

IP rating

A two-digit standard for ingress protection against solids and water.

In an IP rating, the first digit describes protection against solid objects and dust, the second against water. IP66 means fully dust-tight and protected against powerful water jets from any direction, which is the appropriate specification for permanently exposed outdoor installation. Products described only as "weather-resistant" without an IP figure are making an unverifiable claim.

Cane, Camphor and Spirea are IP66-rated.

Marine treatable

Built to tolerate salt-laden, high-humidity coastal air.

Marine treatment addresses corrosion from salt air, which attacks fixings, grilles and chassis over time in ways ordinary humidity does not. It is a separate concern from ingress protection: a product can be sealed against water and still corrode in a coastal environment.

Fire rating

Compliance allowing a speaker to penetrate a fire-rated ceiling or wall.

Cutting into a fire-rated ceiling breaches the fire compartment unless the speaker or its enclosure restores the rating. Where a rated ceiling is involved, this is a building-regulations requirement rather than an audio preference, and it is checked at inspection.

Dolby Atmos height channel

A ceiling or upward-firing channel carrying overhead sound.

Atmos adds height channels above the listener so that sound can be placed overhead rather than only around them. In architectural systems these are normally in-ceiling speakers, positioned to Dolby's published angle guidance relative to the primary seat rather than to the room's geometric centre.

Ghost 2.0 is commonly specified as an Atmos height channel.

Bill of quantities (BOQ)

An itemised schedule of every product and quantity a project requires.

A BOQ lists speakers, amplifiers, accessories, cable and quantities for an installation, and forms the basis of pricing and procurement. Generating it from an actual room design rather than by hand is what prevents the two most common project errors: missing accessories and undercounted amplifier channels.

See the numbers side by side.

Every XSCACE product’s depth, power, sensitivity, frequency range and impedance in a single comparison table — or read how these decisions played out in real installations.

Compare All Specs →Case Studies →Browse Products →

Architectural audio,term by term.