Found a collection of EGG-related research articles available for free through CMU account login at ScienceDirect
Annotated research article “Variation of electrolaryngographically derived closed quotient for trained and untrained adult female singers” (David Howard)
Found important data that will likely be useful for deriving a ground-truth metric of ideal CQs for men and women
Identified methodology concern about basing ideal CQs off of the data presented in this paper
The researchers note that the ideal CQs they derive are based off singers who are already trained, but that more research should be done to confirm these ideal ranges
Researchers suggest following changes in CQ ranges for singers being trained over time. If by the time those singers are considered “trained”, their CQ ranges matches those of the trained singers in this study, that would suggest their proposed ideal CQ ranges are a good basis for ground-truth
Identified methodology concern about CQ measurement for singing that includes varying frequencies
The laryngeal significantly changes between low and high pitches which can cause inaccurate CQ measurements from the sensors
Researchers in this paper addressed this by asking singers to adjust the placement of the sensors with their fingers as they were changing pitch, but this would be a problem for us since we are trying to develop a methodology that is comfortable and does not significantly impact singing physically or psychologically (i.e. making the singers overly self conscious while they sing)
Identified statistically significant CQ trends observed in trained singers
Trained singers were significantly associated with higher CQs across the board; “Howard et al. (23) suggest that an increase in CQ with singing training/experience could be interpreted in terms of a more physically efficient voice usage”
Trained male singers tend to have a CQ range that remains constant
Trained female singers tend to have a CQ ranges that increases with frequency
EGG Hunt
Met with Prof. Helou at Forbes Tower to pick up the EGG, but she had not actually had a chance to find it yet; it is most likely in her other office at PMC
Prof. Helou plans to pick up the EGG from her PMC office on Monday and drop it off at CMU campus either Monday or Tuesday
During my visit, we discussed the CQ measurement methodology concern that the research article “Variation of electrolaryngographically derived closed quotient for trained and untrained adult female singers” (Howard) brings up
Prof. Helou confirmed this is an important methodology concern that she encountered, where she also mentioned it was difficult to move the sensors with the changing laryngeal height
Prof. Helou suggested considering limiting the variation in frequency range for a given measurement, however this would also mean our app would no longer be geared towards providing visual feedback for any music the user chooses to sing, since the change in frequency of sung notes would have to be limited
As described in Ground-Truth Research, asking the user to support the sensors manually is another proposed solution, but other approaches should be researched and considered for appropriate and comfortable sensor calibration
