07-10-2014, 01:17 AM
So, I did some measurements again. These are made with a Samsung S2 and with the speaker near the mic hole in a position that produces the greatest levels. The levels I list are peak levels. For comparison, I also did the measurements with my average-quality Sony in-ear plugs.
While I sleep, I listen to the Trickling stream track with the level peaks at around -60dB. At that volume:
-Sony in-ears: a -60dB peak @ 5kHz and a lower one @ 2kHz.
-SleepPhones: a wide -60dB peak @ 500-1500Hz. Complete silence @ 5kHz.
The ultrasonic track at that same volume setting:
-Sony in-ears: a sharp -60dB peak @ 18kHz.
-SleepPhones: absolutely nothing (no change to background noise)
When I set my phone to full volume, both speakers produce around -40 to -35dB with the masked track, with similar frequency profiles as above. Full volume with the ultrasonic track produces:
-Sony in-ears: -35dB
-SleepPhones: -55dB
Now I find the masked track frequence profiles unsettling, because I don't know where the suggestions lie?? Typical male speech seems to be recorded below 4kHz... Shannon is using a speech synthesizer, so that probably produces a narrower freq. band?
I had this feeling that its probably somehow easier for my brain to interpret the masked tracks than US tracks, but now it seems that I should go with the US track purely because its something I can easily measure with Frequencee. Too much uncertainty with the masked tracks unless I know what frequencies are important. I'd be so nice if there was an instant way to test whether the messages get through or not, like the sleep aid or something that makes me speak in tongues or whatever. Now it can take months.
While I sleep, I listen to the Trickling stream track with the level peaks at around -60dB. At that volume:
-Sony in-ears: a -60dB peak @ 5kHz and a lower one @ 2kHz.
-SleepPhones: a wide -60dB peak @ 500-1500Hz. Complete silence @ 5kHz.
The ultrasonic track at that same volume setting:
-Sony in-ears: a sharp -60dB peak @ 18kHz.
-SleepPhones: absolutely nothing (no change to background noise)
When I set my phone to full volume, both speakers produce around -40 to -35dB with the masked track, with similar frequency profiles as above. Full volume with the ultrasonic track produces:
-Sony in-ears: -35dB
-SleepPhones: -55dB
Now I find the masked track frequence profiles unsettling, because I don't know where the suggestions lie?? Typical male speech seems to be recorded below 4kHz... Shannon is using a speech synthesizer, so that probably produces a narrower freq. band?
I had this feeling that its probably somehow easier for my brain to interpret the masked tracks than US tracks, but now it seems that I should go with the US track purely because its something I can easily measure with Frequencee. Too much uncertainty with the masked tracks unless I know what frequencies are important. I'd be so nice if there was an instant way to test whether the messages get through or not, like the sleep aid or something that makes me speak in tongues or whatever. Now it can take months.
Thoughts, opinions and beliefs subject to change without prior notice.
