CTS CTL DTU CTZ

CTS/CTL/CTU/CTZ - Cross-Talk Attenuators Series

Features

The Q-Tech range of Cross-Talk attenuators has been designed to provide a low resistance to air flow whilst maintaining a high degree of acoustic attenuation.
The CT series should be considered wherever a relief air passage is required to penetrate a building’s acoustic barrier.
Four styles are available in both standard and high-performance configurations: -

- CTS - for simple wall penetration above ceiling
- CTL - wall to ceiling penetration
- CTU - ceiling to ceiling penetration
- CTZ - installation within the wall

Dimensions

	Transmission Loss, dB
	Octave Band Centre Frequency (Hz)						Length
Model ..	125	250	500	1k	2k	4k	L, mm
CTS 1	14	18	21	29	30	25	900
CTS 2	20	26	35	40	40	40	1800
Width, W	300 to 1200 in increments of 150mm
Depth, D	200, 300 & 400mm

	Transmission Loss, dB
	Octave Band Centre Frequency (Hz)						Length
Model ..	125	250	500	1k	2k	4k	L, mm
CTL 1	15	19	23	31	35	30	900
CTL 2	21	27	36	40	40	40	1800
Width, W	300 to 1200 in increments of 150mm
Depth, D	200, 300 & 400mm

	Transmission Loss, dB
	Octave Band Centre Frequency (Hz)						Length
Model ..	125	250	500	1k	2k	4k	L,mm
CTU 1	15	20	24	35	38	35	900
CTU 2	21	28	36	40	40	40	1800
Width, W	300 to 1200 in increments of 150mm
Depth, D	200, 300 & 400mm

	Transmission Loss, dB
	Octave Band Centre Frequency (Hz)						Length
Model ..	125	250	500	1k	2k	4k	L, mm
CTZ 1	15	20	24	35	38	35	900
CTZ 2	21	28	36	40	40	40	1800
Width, W	300 to 1200 in increments of 150mm
Depth, D	200, 300 & 400mm

Performance

Table 1	Air Volume, L/sec, W-width, mm
D, mm	300	450	600	750	900	1050	1200
200	90	135	180	225	270	315	360
300	135	200	270	340	400	475	540
400	180	270	360	450	540	630	720
The air flows tabulated are based upon a maximum pressure loss of 15 Pa.

Installation

Special care should be taken when installing CT Series Cross- Talk units to ensure maximum performance.
Consideration must be given to the sound rating of the wall or ceiling being penetrated.
It is essential that a tight airseal is achieved between the crosstalk unit and the wall/ceiling penetration.
When high performance units are used additional mass lagging of the unit casing may be required to prevent flanking transmission.
This can usually be provided by building-in the cross-talk unit during the building construction phase.

Mounting Arrangements

Note: Airflow shown as a guide only (can travel in either direction)

Suggested Specifications

Room to room Cross-Talk attenuators shall be similar to Q-Tech CT models and shall have the acoustic performance as scheduled.
The cross-talk attenuators shall be of a proven design and must have an established history of use.
Each unit shall consist of a galvanised sheet metal casing and be provided with internal parallel splitters.
The splitter infill material shall be a sound absorbing material as specified by the manufacturer.
The infill material shall be covered with a gauze scrim to prevent erosion of the fibres then encased in galvanised perforated sheet metal.
The infill material when tested in accordance with AS1530, Part 3, 1989 shall have the following indices: -

- Ignitability 0
- Spread of flame 0
- Heat evolved 0
- Smoke developed 0

The contractor shall ensure that an airtight seal is achieved around all wall penetrations to maintain acoustic integrity.
Where necessary additional mass lagging shall be applied to the outside of the attenuators to prevent flanking transmission.
All units shall have a constant active acoustic length irrespective of grille or section size.
Standard units shall have an active length of 900mm and high-performance units an active length of 1800mm.
Acoustic performance specified is quoted as transmission loss as defined in AS1191:1985.

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