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Cirrus Research · Quantum · Noise monitoring station

Quantum Indoor (CR:900 / CR:901)

Current

Fixed indoor noise monitor powered over Ethernet for long-term occupational and entertainment noise monitoring, with Ethernet, dual-band WiFi and Bluetooth connectivity to the MyCirrus cloud platform. Measures all weightings in parallel with 1:1 and 1:3 octave bands and event-triggered audio; the CR:900 is Class 2 with a fixed microphone and the CR:901 is Class 1 with a remote microphone.

Specifications verified on .

Type
Noise monitoring station
Class
Class 1
Channels
1
Octave bands
1/1 and 1/3
Connectivity
Ethernet, WiFi 2.4 and 5 GHz, Bluetooth
Weight
1200 g
Compare with other instrumentsAll noise monitoring stations

Specifications

As published by Cirrus Research. Fields the manufacturer does not publish are omitted rather than estimated.

Standards and class — Quantum Indoor (CR:900 / CR:901)
SpecificationValue
IEC 61672-1 classClass 1
StandardsIEC 61672-1:2013 class 1 (CR:901) or class 2 (CR:900), IEC 61260:1995 (1:1 and 1:3 octave band filters), ANSI S1.4-1983 (R2006), ANSI S1.43-1997 (R2007), ANSI S1.11-2004, EN 61000-6-3:2007+A1:2011, EN 61000-6-1:2007
Measurement — Quantum Indoor (CR:900 / CR:901)
SpecificationValue
Channels1
Measurement range20 to 140 dB RMS, single range
Frequency range6.3 Hz to 20 kHz (1:3 octave bands)
Frequency weightingsA, C, Z
Time weightingsF, S, I
Simultaneous weightingsYes
ParametersLAeq, LCeq, LZeq, LCeq-LAeq, LAE, LEX,8h, LAFmax, LASmax, LCpeak, LAF1, LAF5, LAF10, LAF50, LAF95, LAF99, LAeq,T1 and LAeq,T2
Analysis — Quantum Indoor (CR:900 / CR:901)
SpecificationValue
Octave bands1/1 and 1/3
Audio recordingYes
Logging and data — Quantum Indoor (CR:900 / CR:901)
SpecificationValue
Shortest logging interval10 ms
Memory4 GB standard (about 30 days of measurement data or 24 h of standard audio)
Hardware — Quantum Indoor (CR:900 / CR:901)
SpecificationValue
MicrophoneMK:224 pre-polarised
Weather sensorsNo
Displaynone
External powerPoE IEEE 802.3af (37 to 57 V DC), approx. 5 W
Weight1200 g
Dimensions (mm)127 x 360 x 66
Operating temperature (°C)-10 to 50
Connectivity and software — Quantum Indoor (CR:900 / CR:901)
SpecificationValue
ConnectivityEthernet, WiFi 2.4 and 5 GHz, Bluetooth
Remote controlMyCirrus cloud platform (Quantum portal) and MyCirrus mobile app
SoftwareMyCirrus, NoiseTools, MyCirrus app

Variants

Variants of the Quantum Indoor (CR:900 / CR:901) as the manufacturer names them
VariantDifference
CR:900IEC 61672-1:2013 class 2, fixed microphone
CR:901IEC 61672-1:2013 class 1, remote microphone

Where this data comes from

Manufacturer documents used for this record
KindDocumentAccessed
Product pageQuantum Indoor
DatasheetQuantum Indoor datasheet (English)
ManualQuantum Indoor quick start guide

Verified on . Only the manufacturer’s own published material is used; distributor pages are not sources.

Spec out of date? Tell us (reference cirrus-quantum-indoor).

Verified owner reviews

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Known issues and firmware notes

Hardware and firmware problems reported by owners, with the firmware version concerned and any manufacturer response.

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Feature requests

Functions owners would like to see in a firmware update or a successor model.

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