3 ms·

Just to be clear, this seems to be the first monolithic MEMS speaker, which I take to mean that the speaker array is fabbed as one die, as opposed to each speak

by shard 6y ago

Just to be clear, this seems to be the first monolithic MEMS speaker, which I take to mean that the speaker array is fabbed as one die, as opposed to each speaker being a separate piece of silicon. There are already MEMS speakers available before this. Also, for mobile devices, MEMS have been used for a long time now, specifically for the microphone and IMU (inertial measurement unit -- consisting of accelerometer, gyroscope, magnetic sensor).

IshKebab 6y ago
MEMS speakers are not used in phones (in general; I'm sure someone will nitpick). A speaker is very different to a microphone.
- dwohnitmok 6y ago
  > A speaker is very different to a microphone. Is it? I've definitely had fun little experiments where I turn a microphone into a speaker or use a speaker as a microphone. It's just a matter of whether I'm powering the membrane or whether the membrane is powering me, i.e. its just a matter of which side of the mechanism I sit on. It's a conversion between electricity and mechanical vibration that can be driven from either side. I'm sure there's a lot of engineering trade-offs that change if you're looking to optimize for recording fidelity vs output fidelity, so the details of their implementation are probably quite different, but at their core the two don't seem all that different. Maybe they're totally different in the MEMS world?
  - shard 6y ago
    Obviously depends on the type of speaker and microphone, but I have actually used headphones as a mic in a pinch before (in a lab setting, not in everyday use).
  - leetbulb 6y ago
    I'm with you on the speaker versus microphone. Both piezo and magnetic coil driven can be used both ways. Just like an electric motor versus an alternator. They're essentially the same thing, but optimized for different purposes.
  - anamexis 6y ago
    I think the engineering trade-offs are significantly large enough to make microphones and speakers "totally different" in the conventional, non-MEMS world. Sure, at the very core of it, it's just trading electricity for mechanical vibration, and this functions in both directions. But the engineering that has gone into specializing both speakers and microphones is staggering.
- shard 6y ago
  Just in case it's not clear, I stated that MEMS mics and IMUs are used in smartphones, and that MEMS speakers have been available for a while now. If it seemed like I said MEMS speakers are used in smartphones, that was unintentional.

by shard 6y ago

IshKebab 6y ago

MEMS speakers are not used in phones (in general; I'm sure someone will nitpick). A speaker is very different to a microphone.

dwohnitmok 6y ago
> A speaker is very different to a microphone. Is it? I've definitely had fun little experiments where I turn a microphone into a speaker or use a speaker as a microphone. It's just a matter of whether I'm powering the membrane or whether the membrane is powering me, i.e. its just a matter of which side of the mechanism I sit on. It's a conversion between electricity and mechanical vibration that can be driven from either side. I'm sure there's a lot of engineering trade-offs that change if you're looking to optimize for recording fidelity vs output fidelity, so the details of their implementation are probably quite different, but at their core the two don't seem all that different. Maybe they're totally different in the MEMS world?
- shard 6y ago
  Obviously depends on the type of speaker and microphone, but I have actually used headphones as a mic in a pinch before (in a lab setting, not in everyday use).
- leetbulb 6y ago
  I'm with you on the speaker versus microphone. Both piezo and magnetic coil driven can be used both ways. Just like an electric motor versus an alternator. They're essentially the same thing, but optimized for different purposes.
- anamexis 6y ago
  I think the engineering trade-offs are significantly large enough to make microphones and speakers "totally different" in the conventional, non-MEMS world. Sure, at the very core of it, it's just trading electricity for mechanical vibration, and this functions in both directions. But the engineering that has gone into specializing both speakers and microphones is staggering.
shard 6y ago
Just in case it's not clear, I stated that MEMS mics and IMUs are used in smartphones, and that MEMS speakers have been available for a while now. If it seemed like I said MEMS speakers are used in smartphones, that was unintentional.