Altitude from the sea level. Attenuator selection beased on the below factors consideration.
Low frequency noise is more difficult to attenuate than high frequency.
How to select sound attenuator. The program produces a report that displays whether or not your design meets your required noise level within the critical space. Attenuator pressure loss across the ductig system. FANTECH 2016 NOISE CONTROL PRODUCTS H-3 ATTENUATOR SELECTION PROCEDURE 2.
Graph 1 Instructions for Selection of Sound Attenuators by simple calculation method Graph 2 34 Select an attenuator type and code from S1020 Series Tables for required acoustic performance. The first module comprises two half width side liners plus an airway. As a result you may choose from a selection of standard or custom engineered duct silencers that will satisfy the requirements of each application.
Passive attenuators provide most attenuation in the mid to high frequency range but mechanical plant often produces a significant proportion of its acoustic energy in the lower frequency range. This value is to be deducted from the sound power level LWAtotal of the fan. 1 Select the appropriate noise reduction data column.
The first to the signal pin while the second in parallel from signal to ground pin. It is necessary to know the noise spectrum of a fan octave or tierce spectrum to choose an attenuator. How to Select an Attenuator Configuration.
How to select the sound attenuator To properly select the type of the duct silencer you need to consider the permissible flow velocity depending on the flow rate and the specific noise of the silencer. Software enabled selection programme Select attenuators from the Airwellcare range and choose construction features and options for each attenuator. Therefore a larger or more resistive attenuator is required.
If the sound levels are not met the program will automatically chooses a duct silencer for you based on your. Often you can easily unplug that cable and plug in an attenuator in between Once in place just turn up your amp to get your desired tone and use the attenuators controls to find the right overall volume. To make an attenuator selection that will provide satisfactory performance there are several criteria that have to be addressed.
Choose the most appropriate attenuator. In a HVAC System where its applied and what is the maximum allowable decibel. Where only moderate attenuation is required this discrepancy may not be significant with the higher frequency.
I have an Oppo Sonica DAC which has 4 Vrms through the balanced outputs and a Classe Amp2 and a CAV-180 for that matter which takes 14 Vrms maximum input without clipping. Note that the each type is available in lengths from 300mm to 2400mm. Kinetics offers the design and engineering assistance to integrate our line of duct silencers sound attenuators into a system solution.
After this operation the two resistors are interwoven and slightly soldered each other. The critical octave bands for evaluating sound performance ranges from 63 to 8000 Hz. Attenuator Pressure Loss A sound attenuator restricts the passage of air flow through it.
You can choose the female connector for this operation but the reverse is also fine. How to choose an attenuator. Acoustic attenuationsilencing performance The reduction in noise offered by an acoustic attenuator varies according to the source of the noise being controlled.
Quick selection of an attenuator An average insulation value is stated in the type table column with the red background on the far right for a quick selection of pipeline and duct attenuators. Select attenuators based on various parameters of input data such as attenuator or duct size air volume pressure loss insertion loss etc. From this simple idea there are many varieties of attenuators available.
2 Choose the attenuator series required. A combination of acoustic splitter and airway produces an attenuator module. It is advisable to cover bare wires and resistors with shrink tubing and insulating tape.
SOUND ATTENUATOR Noise Criteria NCis a single number rating derived from sound pressure levels in all eight octave bands and is intended to predict an occupants response to the overall sound level. As a result you get the sound power level of the fan reduced by the noise. The efficiency of an attenuator is largely dependent on the frequency of the sound source therefore the attenuation is stated over the octave spectrum.
– Calculated insertion loss. The program will give the following results. Ventilation Selection Program and Elta Fans Website.
Prime candidates for noise control measures are openings into and. The restriction of the attenuator is defined in Pa of static pressure loss. I was recommended to use 24dB attenuators to reduce voltage.
But this seemed very high to me based on online voltage to dB converters. It is a true model-all program. Many sound attenuator manufacturers offer special silencer selection tool including Alnor our silencer selection tool is called AlnorSILENT.
– Attenuator insertion loss dB. Use the project for choosing the different types of attenuators and download the selection cards in one file. Also the attenuator can be no longer than 2200mm long is not exposed to the weather and can have no more than 20Pa of air flow resistance through it to avoid affecting the fan selection.
Exhaust fan noise would be classified as General Fan noise. The pressure loss of the attenuators in this catalogue is charted in two different ways. Selection is prepared using a computer aided program.