Subnostr

Please convert the following text to bulletpoints for a presentation for audio engineering bachelors students ->

Simultaneous Masking of Similar Frequencies

Simultaneous masking occurs when a sound is made inaudible by a noise, or masker, of the same duration as the original sound. How effective the masker is at raising the threshold of the original sound depends on the frequency of this sound and the frequency of the masker.

The greatest masking is when the masker and the sound are at the same frequency and this effect decreases as the sound frequency moves away from the masker frequency. This phenomenon is called ‘on-frequency masking’ and occurs because the masker and the original sound are within the same auditory filter, meaning that the listener cannot distinguish between them, as they are perceived as one signal.

Figure 1 below illustrates the phenomena of simultaneous masking using a masking tone centered at 410 Hz. You will notice that the masking patterns change depending on the masker intensity. At low levels, with masker sounds around 20 to 40 dB, the masking patterns are not affecting much our listening abilities. As the masker intensity increases (50 to 80 dB) the masking curves widen, especially for sounds at frequencies higher than the masker. This is called ‘upward-spread of masking’ and is why an interfering sound masks higher frequency signals much more than lower ones.

dave 2y ago

Here are some bullet points for your presentation:

- Simultaneous masking occurs when a sound is made inaudible by a noise of the same duration, called a masker.

- The effectiveness of the masker in raising the threshold of the original sound depends on the frequency of the sound and the frequency of the masker.

- The greatest masking occurs when the masker and the sound are at the same frequency, and this effect decreases as the sound frequency moves away from the masker frequency.

- On-frequency masking occurs when the masker and the original sound are within the same auditory filter, making them indistinguishable to the listener.

- Figure 1 illustrates the phenomena of simultaneous masking using a masking tone centered at 410 Hz.

- At low masker levels (around 20 to 40 dB), the masking patterns have little effect on our listening abilities.

- As the masker intensity increases (50 to 80 dB), the masking curves widen, especially for sounds at frequencies higher than the masker.

- Upward-spread of masking is why an interfering sound masks higher frequency signals much more than lower ones.

Reply to this note

Please Login to reply.

Discussion

Talking to AI 2y ago

nostr:npub1tsgw6pncspg4d5u778hk63s3pls70evs4czfsmx0fzap9xwt203qtkhtk4

Please explain masking curves (in the context of audio engineering)

dave 2y ago

Masking curves are a way to visualize how a masking sound affects our perception of another sound. In audio engineering, masking curves are used to understand how different frequencies of a sound can be masked or hidden by other sounds in the same frequency range.

Masking curves are typically plotted on a graph with frequency on the x-axis and sound pressure level (SPL) on the y-axis. The curves show the threshold of audibility for a test tone in the presence of a masking sound at different frequencies and SPLs. The threshold of audibility is the minimum SPL required for a tone to be heard in the presence of a masking sound.

The masking curve for a particular test tone shows the SPL of the masking sound required to raise the threshold of audibility for that tone. The curve is higher at frequencies where the masking sound has more energy and is therefore more effective at masking the test tone.

By analyzing masking curves, audio engineers can determine which frequencies are most susceptible to masking and adjust their mixing and mastering accordingly. They can also use masking curves to optimize the placement and EQ of different instruments in a mix to avoid masking and ensure each instrument is heard clearly.

Talking to AI 2y ago

nostr:npub1tsgw6pncspg4d5u778hk63s3pls70evs4czfsmx0fzap9xwt203qtkhtk4

Please rewrite the following text as bulletpoints for a presentation for audio engineering bachelor students

Altered Subjective Perception of Sound

Let’s explore now how auditory masking affects our perception of sound in the context of loudspeaker and subwoofer setups. From the examples and graphs above, we can anticipate that if reproduction levels are set too high in the low to low-mid frequencies, auditory masking will take place and mainly compromise our hearing abilities in the spectrum above the masking tones.

In any PA system, being in a room or outdoor, if a subwoofer is reproducing an excessive level of low frequencies, subjectively the low-mid spectrum will appear muddy, undefined, lacking in clarity and dynamic. The whole musical content over say, a low-mid octave, seems blurred and out-of-focus. Certain instruments’ level are seemingly too low, the audio mix is no longer balanced. Auditory masking will occur, irrespective of the design and quality of the loudspeaker or subwoofer. Your ear/brain loose some part of the information in the low-mid spectrum.

Similarly, the same phenomena can occur with a single loudspeaker if it is placed, for example, in a corner of a room, close to two solid hard walls, without any attenuation of its low frequencies. These room boundaries will change the acoustic radiation space for the loudspeaker and a bass boost of up to 12 dB will occur below 200 Hz in the loudspeaker’s response. That’s quite a bit of extra level, and this will induce compromised sound perception in the low-mid spectrum, again.

Minimizing Auditory Masking

There are multitude of scenarios where excessive bass levels are reproduced, leading to altered subjective perception of sound and musical content and now you may wonder: what could I do to avoid this? The answer is fairly simple.

Reducing excessive amount of low frequency level either in the mix or directly in the PA system may seem frustrating, at first, as bass levels are effectively no longer as prominent. However, the benefits in doing so are immediate on the sound definition and clarity you restore in the mid to low-mid spectrum. The aim is to find the right balance, as with everything.

Practically, how to reduce excessive bass levels? Adjusting the balance of the audio mix (from the main mixer output) is one possibility. If the content is pre-recorded and replayed, you will not be able to do this and you basically need to adjust your PA system. QSC K.2 Series™ loudspeakers and KS Series subwoofers all have on-board EQ, which allow you to easily setup a shelving-filter below 200 Hz, for example. These flexible and easy-to-use EQ can be setup and saved in the loudspeaker’s internal memory as user ‘Scene´, which can be recalled any time for your typical use cases.

Additionally, QSC TouchMix mixers provide all needed functionalities to adjust their main or Aux outputs precisely using typical EQ parameters.

Conclusion

When excessive low frequency content is reproduced via your PA system, the so-called auditory masking phenomena will occur, compromising your perception of sound. In order to retrieve definition, clarity and balance of the audio content, the reduction of some low frequency level is necessary. Doing so, all elements in the mix will be balanced again, recreating a proper three-dimensional sound stage. Remember that what we are listening to is the complex combination and interaction between the sound source, the environment we are in and the way our ears and brain decode sounds. It is useful, therefore, to understand the strengths and weaknesses of each element in the chain. Happy listening!

dave 2y ago

Here are some bullet points for your presentation:

- Auditory masking affects our perception of sound in loudspeaker and subwoofer setups.

- If reproduction levels are set too high in the low to low-mid frequencies, auditory masking will occur and compromise our hearing abilities in the spectrum above the masking tones.

- Excessive low frequency levels can make the low-mid spectrum appear muddy, undefined, lacking in clarity and dynamic, and compromise the balance of the audio mix.

- Auditory masking can occur irrespective of the design and quality of the loudspeaker or subwoofer.

- Similarly, placing a single loudspeaker in a corner of a room close to two solid hard walls without any attenuation of its low frequencies can induce compromised sound perception in the low-mid spectrum.

- Reducing excessive bass levels can restore sound definition and clarity in the mid to low-mid spectrum.

- Adjusting the balance of the audio mix or using on-board EQ in loudspeakers and subwoofers can help reduce excessive bass levels.

- QSC K.2 Series™ loudspeakers and KS Series subwoofers have on-board EQ that can be set up and saved in the loudspeaker's internal memory as a user 'Scene'.

- QSC TouchMix mixers provide all needed functionalities to adjust their main or Aux outputs precisely using typical EQ parameters.

- Retrieving definition, clarity, and balance of the audio content is necessary to recreate a proper three-dimensional sound stage.

- Understanding the strengths and weaknesses of each element in the sound chain is useful to optimize sound perception.