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Help in understanding Freq. response
Hello there! I want to understand what is Frequency Response but unfortunately, I can't understand audio jargons    Could someone explain in the simplest way possible? And also, is Frequency Response a good thing in purchasing an headphone or a loudspeaker? If not, then what aspects do you consider in choosing one?
sin(α) = v sound/v object = Mach No.

  • AndyH-ha
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Help in understanding Freq. response
Reply #1
The frequency response is the frequency range over which a device meets certain response qualifications. If the device is fed a constant level signal whose frequency varies, somewhere at the high end the output from the device will start to fall off. For many devices this also happens at the low end. The qualifications are often  +/- some number of dB. Very often cheaper audio devices simply say 20Hz to 20kHz, with no qualifications.

The range for loudspeakers is usually where their response is down 3dB. If the loudspeaker is fed a constant level signal of varying frequency, at some higher frequency the output starts dropping even though the input is constant. The upper end of the specified frequency response curve is where that response is down 3dB compared to what it is over the middle frequencies.

The same happens on the low frequency side. In reality, although the specifications usually say nothing about it, speaker output variations, and especially headphone response variations (very small speakers)  withing that frequency range are often far more than 3dB. The actual frequency response, that is where there is some output for some input, may extend to considerably higher and lower frequencies, but the output is much diminished.

On the other hand, electronic devices, such as amplifiers, may be linear over a large frequency range (i.e. 20Hz to 20kHz, or a much greater range) within a small part of a dB.

  • drewfx
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Help in understanding Freq. response
Reply #2
The simplest explanation is frequency response is "how loud a system or component is at different frequencies".

Ideally everything would be equally loud (flat frequency response) at all frequencies, but in reality things will vary somewhat.

  • Fedot L
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Help in understanding Freq. response
Reply #3
Hello there! I want to understand what is Frequency Response but unfortunately, I can't understand audio jargons. Could someone explain in the simplest way possible?

My version of explanation.

Frequency Response graph lets you see how the sound intensity created by a LS or a headphone changes at any frequency compared with the sound intensity created at any other frequency while the signal level sent to the LS or a headphone stays constant. I.e. the irregularity of a LS or a headphone acoustic output.

Each step of 3 dB means twice sound intensity radiation (by a LS or headphone) change.
Each step of 6 dB means four times sound intensity radiation (by a LS or headphone) change.

Each step of 4…6 dB at the lowest frequencies means approx. twice sound intensity perception change.
At the frequencies over 700 Hz, each step of 8…10 dB means approx. twice sound intensity perception change.

The values in dB are to be added up for to see the resulting change value. 6+6 dB = 12 dB. Etc.

The overall range irregularity comparison is usually done compared to 1000 Hz. At the lowest frequencies, it would be more useful to do compared to 100 Hz.
  • Last Edit: 17 August, 2011, 01:55:38 PM by Fedot L