View previous topic :: View next topic |
Author |
Message |
Silver Sparrow

Joined: 13 Aug 2005 Posts: 489 Location: The part of London with the smallest number of birds

|
Posted: Tue Jul 11, 2006 6:21 pm Post subject: Audible bats |
|
|
Am i missing something here? We used to have bats about 6 or 7 years ago (back in my GCSE days wo00o0h0000) they lived in the church i think. anyway, we could hear their sonar thingies very clearly, they'd even come quite close and nearly swoop over our heads sometimes!
now all the articles on bats say u need that special equipment to modify the bats sonar thing to make it audible to human ears, but our bats were very much audible without any equipment at all. whats going on? _________________ Look upon my lack of talent, ye mighty, and despair! |
|
Back to top |
|
 |
Martin

Joined: 03 Nov 2005 Posts: 843 Location: Stevenage, Herts

|
Posted: Tue Jul 11, 2006 6:47 pm Post subject: |
|
|
age
as you get older you lose more of your high frequencies
I think a device was demonstrated as an effective method of dispersing unwanted youths by emitting high frequencies that only humans below a certain age could hear ! _________________ Martin
http://the2wrennies.co.uk/ |
|
Back to top |
|
 |
Tricia

Joined: 08 Apr 2005 Posts: 3579 Location: Surrey

|
Posted: Tue Jul 11, 2006 10:31 pm Post subject: |
|
|
Martin wrote: | age
as you get older you lose more of your high frequencies
I think a device was demonstrated as an effective method of dispersing unwanted youths by emitting high frequencies that only humans below a certain age could hear ! |
You're right about age Martin. I once heard that a human's hearing reaches it's peak at age 9. Can't quite remember where I heard this, or whether it's fact or not! _________________ Tricia
What is this life if full of care, We have no time to stand and stare?
http://belfiebird.blogspot.com/
Last edited by Tricia on Wed Jul 12, 2006 10:22 pm; edited 1 time in total |
|
Back to top |
|
 |
Silver Sparrow

Joined: 13 Aug 2005 Posts: 489 Location: The part of London with the smallest number of birds

|
Posted: Wed Jul 12, 2006 2:49 pm Post subject: |
|
|
but even my parents could hear it and they were in their late 40s! are we just abnormal... and could this be the reason we could ALL hear the cat repellent (my mum is now in her 50s and she heard it too)
Quote: | I think a device was demonstrated as an effective method of dispersing unwanted youths by emitting high frequencies that only humans below a certain age could hear ! | yes i know about this. Also, now teenagers are getting their own back and using these high frequencies as ring tones so they can use their phones in class without the teacher knowing! _________________ Look upon my lack of talent, ye mighty, and despair! |
|
Back to top |
|
 |
Hampshire Hogg

Joined: 28 Nov 2005 Posts: 119

|
Posted: Wed Jul 12, 2006 4:05 pm Post subject: |
|
|
Another myth is dog whistles.
Where we walk the dogs a lady we know always calls her dogs with a special dog whistle.
The dogs appear to ignore it, but it takes the top of my head off every time she uses it.
I'm 74 ! and my hearing is not what it was, so it's effectiveness is suspect.
I once read an artical by a top wildlife expert who visited the Amazon to make a written record of moths.
He sat outside his tent with his yellow labrador who, as soon as night fell went berserk and refused to leave the tent.
It took him some while to realise that it was the sound from bats which was driving the dog mad.
To a dog it must sound like an express train coming straight at them. |
|
Back to top |
|
 |
Silver Sparrow

Joined: 13 Aug 2005 Posts: 489 Location: The part of London with the smallest number of birds

|
|
Back to top |
|
 |
Nobby
Joined: 24 Mar 2005 Posts: 327 Location: Kenley Surrey UK

|
Posted: Tue Jul 18, 2006 6:13 pm Post subject: |
|
|
Silver Sparrow wrote: | Does anyone know of any recordings of bat calls available for download - at the original frequency? i want to do a little experiment |
If you want to play it back you may need a very good speaker as most work at audible frequencies.
Brett. |
|
Back to top |
|
 |
Silver Sparrow

Joined: 13 Aug 2005 Posts: 489 Location: The part of London with the smallest number of birds

|
Posted: Sun Jul 23, 2006 3:08 pm Post subject: |
|
|
I was wondering about that. But then if mobile phones can play those high frequencies I'm sure my Pc could.. unless of course the story of the ultrasonic ringtone was just a bit of fiction.. like those stupid baa baa rainbow sheep stories everyone always falls for
the problem is how to get hold of a sound clip in the first place. _________________ Look upon my lack of talent, ye mighty, and despair! |
|
Back to top |
|
 |
Hampshire Hogg

Joined: 28 Nov 2005 Posts: 119

|
Posted: Mon Jul 24, 2006 5:19 pm Post subject: |
|
|
How do you know when you have got one.??? |
|
Back to top |
|
 |
Silver Sparrow

Joined: 13 Aug 2005 Posts: 489 Location: The part of London with the smallest number of birds

|
|
Back to top |
|
 |
Nobby
Joined: 24 Mar 2005 Posts: 327 Location: Kenley Surrey UK

|
Posted: Tue Jul 25, 2006 10:34 pm Post subject: |
|
|
Do bat sounds have side tones?
I mean if they produce sound at 44KHz then they would also produce a 22KHz sound at half power.
Perhaps a human with good hearing is hearing this sound?
Brett. |
|
Back to top |
|
 |
Karwin

Joined: 24 Mar 2005 Posts: 2554 Location: 61N25E

|
Posted: Mon Jan 31, 2011 3:38 pm Post subject: |
|
|
Twenty years younger I remember having heard Eptesicus nilssoni. It was like tinnitus from inside my head, but I noticed I heard that always when the bat flew over my head. Here is instead ultrasounds of Eptesicus & Myotis progressed with Pettersson D200 bat detector. The video is by Finnish Association for Nature Conservation, recordings are by me
http://www.youtube.com/watch?v=DOZP7MYVD_s _________________ Save the karri. |
|
Back to top |
|
 |
Peter

Joined: 21 Apr 2005 Posts: 772 Location: South-west England

|
Posted: Mon Jan 31, 2011 10:48 pm Post subject: |
|
|
Karwin wrote: | Twenty years younger I remember having heard Eptesicus nilssoni. It was like tinnitus from inside my head, but I noticed I heard that always when the bat flew over my head. Here is instead ultrasounds of Eptesicus & Myotis progressed with Pettersson D200 bat detector. The video is by Finnish Association for Nature Conservation, recordings are by me
http://www.youtube.com/watch?v=DOZP7MYVD_s |
Well I never thought of using YouTube for that.
Isn't the point Karwin that these are indeed sounds created through a bat detector and are not those that we can hear, as such? What we need is the unfiltered version...good those these are of course...!
All sounds a bit like someone who can tap dance incredibly fast..  |
|
Back to top |
|
 |
Karwin

Joined: 24 Mar 2005 Posts: 2554 Location: 61N25E

|
Posted: Tue Feb 01, 2011 6:22 am Post subject: |
|
|
Peter wrote: | Isn't the point Karwin that these are indeed sounds created through a bat detector and are not those that we can hear, as such? What we need is the unfiltered version...good those these are of course...! | Bat detector amplifies ultrasounds (Ultravox ) to our ears. _________________ Save the karri. |
|
Back to top |
|
 |
Karwin

Joined: 24 Mar 2005 Posts: 2554 Location: 61N25E

|
Posted: Tue May 17, 2011 7:26 am Post subject: |
|
|
Martin wrote: | I think a device was demonstrated as an effective method of dispersing unwanted youths by emitting high frequencies that only humans below a certain age could hear ! | You're right, in a mall of nearby town here in Finland they have used such device. Peter wrote: | these are indeed sounds created through a bat detector and are not those that we can hear | Continuing with experiments on detector bat sounds, here's a bat song I performed some months ago in Finnish year-of-the-bat seminar. All instruments sounds are edited from detector sounds, that were originally created by Finnish bats. Song starts at 0:47 and the words list names of Finnish bats in Finnish, Swedish & Latin.
http://www.box.net/shared/3100h7grm7 _________________ Save the karri. |
|
Back to top |
|
 |
|