Masked threshold shape changes with masker level, becoming more asymmetric at high levels

Evidence

Because post masking lasts much longer than premasking, these differences are to be expected. For a modulation frequency of 8 Hz, this effect becomes more pronounced leading to differences of almost 20 dB in masked threshold for the positions indicated by “2” and “6” at lower critical-band rates. The difference is not as large at higher critical-band rates because of the relatively shallow upper slope of the masking pattern. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 547 (#expands, via linked claim)

The results from Hawkins and Stevens (1950) illustrate a small, but robust, effect of signal frequency. However, we can better observe the relationship between the frequency of maskers and the frequencies of the signals when experiments are conducted under variable frequency conditions. — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 461 (#qualifies, via linked claim)

Measuring PTCs under forward and simultaneously masked conditions illustrates why we must consider both situations. Moore, Glasberg, and Roberts (1984) measured PTCs for a tone presented at 10 dB SL and at four different frequencies under both simultaneous and forward masked conditions. They found that that simultaneousand forward-masked PTCs have a very similar shape, as shown in Figure 3–15. However, we see a striking difference between the two types of PTCs. The PTC measured using simultaneous masking was broader than the PTC measured using forward masking. We also observe evidence of upward spread of masking in the shallower low-frequency tail in both simultaneousand forward-masked conditions, suggesting that upward spread of masking is a robust property of the auditory system. — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 532 (#corroborates, via linked claim)

Categorization

• XREF: connects to: Post masking outlasts premasking and asymmetrically distorts threshold patterns. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 547; Masker peaks at rarefaction produce maximal masking of short tone bursts; Simultaneous tones become harder to perceive due to masking effects — David Howard, Jamie Angus, coustics and Psychoacoustics, 1628 (+2 more)

Related

• Simultaneous masking yields broader tuning curves than forward masking. (similarity 0.92)
• Post masking outlasts premasking and asymmetrically distorts threshold patterns. (similarity 0.91)
• Simultaneous-masked PTCs are broader than forward-masked PTCs, with similar overall shape (similarity 0.90)
• A masker raises the audibility threshold of a test sound. (similarity 0.89)
• Reducing audible fluctuations in a masker lowers post-masked thresholds by up to 24 dB (similarity 0.88)
• Forward masking persists up to 200 ms after the masker ends (similarity 0.88)
• Masking spreads from a noise band to tones further away as masker level rises (similarity 0.87)
• Two-tone suppression makes simultaneous masking appear broader than forward masking (similarity 0.87)
• Increasing stimulus level broadens auditory filters and causes upward spread of masking (similarity 0.87)
• Post masking outlasts premasking and can skew frequency-modulation measurements by nearly 20 dB. (similarity 0.87)
• Masked tones recover pitch strength as their level rises above masked threshold (similarity 0.87)
• A suppressor below masker threshold can reduce forward masking without itself masking the signal (similarity 0.87)
• Masking depends on stimulus fluctuations in ways steady-state models cannot predict. (similarity 0.86)
• Masking operates on a continuous scale between audible and fully masked. (similarity 0.86)
• Post-masking decreases when a second masker suppresses audible masker fluctuations (similarity 0.86)

Broader Connections

• Post masking outlasts premasking and asymmetrically distorts threshold patterns. #expands (0.82) — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 547
• Masking effectiveness depends on masker-signal power, frequency, and timing relationships #qualifies (0.78) — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 461
• Masker peaks at rarefaction produce maximal masking of short tone bursts #expands (0.75)
• Simultaneous masking yields broader tuning curves than forward masking. #corroborates (0.75) — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 532
• Simultaneous tones become harder to perceive due to masking effects #exemplifies (0.72) — David Howard, Jamie Angus, coustics and Psychoacoustics, 1628