4 ms·

When I lived in Nob Hill, there was a quiet long beeping sound that could be heard every couple of minutes - imagine a quiet booooop and you're pretty much ther

by johnfn 6y ago

When I lived in Nob Hill, there was a quiet long beeping sound that could be heard every couple of minutes - imagine a quiet booooop and you're pretty much there. Definitely sounded electronic. The weird thing was I could actually hear it on quiet days in a large radius in Nob Hill. It didn't seem to be localized on my house. I was never able to identify it, and searching online gave me nothing.

qppo 6y ago
I had this problem in college. Turned out to be the wind blowing over a small hole in a pipe, creating a whistle.
komali2 6y ago
It wasn't the foghorn was it?
mareko 6y ago
Could you be hearing one of the many foghorns in the bay? https://youtu.be/jJWd5eHeFY4 https://youtu.be/jJWd5eHeFY4
- johnfn 6y ago
  Pretty interesting hypothesis! I don't think so, though. It was a fairly electronic sounding boop, almost like a low sine wave. A fog horn sound has more acoustic qualities to it. Also, if it was a fog horn, I don't know why it would only be audible in Nob Hill and no where else I've been in SF.
  - closeparen 6y ago
    The Bay foghorns are electronic tones; they don’t sound like classic/cartoon foghorns at all.
    - stn8188 6y ago
      If it's anything like the most common fog horn that the USCG uses across the country, it's a 273Hz tone (though I don't recall the waveform, most likely sinusoidal). As of 8 years ago, they were using the FA-232 model fog horn, the circuitry was designed in the '70s and uses discrete BJTs on the boards to generate the tone and drive the "speaker".
    - johnfn 6y ago
      Wow. I went online and found an audio recording: https://www.youtube.com/watch?time_continue=12&v=CPUs2KnAyhU&feature=emb_title https://www.youtube.com/watch?time_continue=12&v=CPUs2KnAyhU... Yup, the tone at 0:08 is pretty much the exact tone I heard. Mind-blowing. Never would have imagined that's what a fog horn sounded like. I expected them to all be much deeper tones like the ones that come a few seconds later. I guess there must be weird acoustic qualities that make only the higher toned ones carry into Nob Hill.
- wpietri 6y ago
  In the Mission I could occasionally hear foghorns, which made no sense to me. It was generally around first light in the morning. After quite a lot of digging, including making heatmaps of where ships parked, I traced it to Anchorage No 9, which is basically a parking lot for giant ships. You can see it when crossing the Bay Bridge. More details and maps here: https://www.facebook.com/williamp/posts/10106726609193073 https://www.facebook.com/williamp/posts/10106726609193073
rasz 6y ago
chirping smoke alarm? Saw a YT clip of a dude hunting for annoying beep with army of audio recorders, turned out to be battery depleted fire alarm under the stairs.
- johnfn 6y ago
  Considered this too, but there are two reason I ruled it out: 1. The beep was very long - maybe a second or two - much longer than smoke alarms. 2. I could hear it blocks away from my apartment. No smoke alarm chirp would carry that far.
  - lttlrck 6y ago
    Perhaps a UPS complaining that its battery is dying/dead?
dfischer 6y ago
I hear this all the time. I was just talking to someone about it. It’s not everyday but it’s frequent. I hear it mostly in the morning and at night. It’s always the same length, about a second. It’ll come in pulses of 2 or 3 usually. Spread out a few minutes a part. It definitely sounds like an electronic sound. Almost like a sci fi satellite sound but deep in the water far away. Or maybe a far away whale mourning or something. I just traveled for 3 months and heard it spread across 10 cities. It’s very weird...
- underwater 6y ago
  Power companies transmit a signal at certain times of the day through the lines. This controls devices that can switch between day and night mode. My ceiling fans will buzz when it's happening. Sounds almost like the old SMS interference you'd get with FM radio.
  - dimnsionofsound 6y ago
    This is called Ripple Control, for anyone interested: https://en.wikipedia.org/wiki/Load_management#Ripple_control https://en.wikipedia.org/wiki/Load_management#Ripple_control
    - underwater 6y ago
      Thanks. I was struggling to remember the name.

by johnfn 6y ago

qppo 6y ago

I had this problem in college. Turned out to be the wind blowing over a small hole in a pipe, creating a whistle.

komali2 6y ago

It wasn't the foghorn was it?

mareko 6y ago

Could you be hearing one of the many foghorns in the bay? https://youtu.be/jJWd5eHeFY4 https://youtu.be/jJWd5eHeFY4

johnfn 6y ago
Pretty interesting hypothesis! I don't think so, though. It was a fairly electronic sounding boop, almost like a low sine wave. A fog horn sound has more acoustic qualities to it. Also, if it was a fog horn, I don't know why it would only be audible in Nob Hill and no where else I've been in SF.
- closeparen 6y ago
  The Bay foghorns are electronic tones; they don’t sound like classic/cartoon foghorns at all.
  - stn8188 6y ago
    If it's anything like the most common fog horn that the USCG uses across the country, it's a 273Hz tone (though I don't recall the waveform, most likely sinusoidal). As of 8 years ago, they were using the FA-232 model fog horn, the circuitry was designed in the '70s and uses discrete BJTs on the boards to generate the tone and drive the "speaker".
  - johnfn 6y ago
    Wow. I went online and found an audio recording: https://www.youtube.com/watch?time_continue=12&v=CPUs2KnAyhU&feature=emb_title https://www.youtube.com/watch?time_continue=12&v=CPUs2KnAyhU... Yup, the tone at 0:08 is pretty much the exact tone I heard. Mind-blowing. Never would have imagined that's what a fog horn sounded like. I expected them to all be much deeper tones like the ones that come a few seconds later. I guess there must be weird acoustic qualities that make only the higher toned ones carry into Nob Hill.
wpietri 6y ago
In the Mission I could occasionally hear foghorns, which made no sense to me. It was generally around first light in the morning. After quite a lot of digging, including making heatmaps of where ships parked, I traced it to Anchorage No 9, which is basically a parking lot for giant ships. You can see it when crossing the Bay Bridge. More details and maps here: https://www.facebook.com/williamp/posts/10106726609193073 https://www.facebook.com/williamp/posts/10106726609193073

rasz 6y ago

chirping smoke alarm? Saw a YT clip of a dude hunting for annoying beep with army of audio recorders, turned out to be battery depleted fire alarm under the stairs.

johnfn 6y ago
Considered this too, but there are two reason I ruled it out: 1. The beep was very long - maybe a second or two - much longer than smoke alarms. 2. I could hear it blocks away from my apartment. No smoke alarm chirp would carry that far.
- lttlrck 6y ago
  Perhaps a UPS complaining that its battery is dying/dead?

dfischer 6y ago

I hear this all the time. I was just talking to someone about it. It’s not everyday but it’s frequent. I hear it mostly in the morning and at night. It’s always the same length, about a second. It’ll come in pulses of 2 or 3 usually. Spread out a few minutes a part. It definitely sounds like an electronic sound. Almost like a sci fi satellite sound but deep in the water far away. Or maybe a far away whale mourning or something. I just traveled for 3 months and heard it spread across 10 cities. It’s very weird...

underwater 6y ago
Power companies transmit a signal at certain times of the day through the lines. This controls devices that can switch between day and night mode. My ceiling fans will buzz when it's happening. Sounds almost like the old SMS interference you'd get with FM radio.
- dimnsionofsound 6y ago
  This is called Ripple Control, for anyone interested: https://en.wikipedia.org/wiki/Load_management#Ripple_control https://en.wikipedia.org/wiki/Load_management#Ripple_control
  - underwater 6y ago
    Thanks. I was struggling to remember the name.