I have a niece in Costa Rica who is homeschooling due to COVID. She uses an Apple iPad to take classes. I think it's 3rd grade so the kids are screaming and the teacher has a high pitched voice.
The homes in Costa Rica are plaster walls with tile floors. No curtains because lizards and tarantulas like to hide in stuff like that.
Sister-in-law is pulling her hair out from the screeching noise -- ALL DAY LONG. I'm thinking about sending a speaker down to them if it can help.
What kind of speaker and room placement would you design in this case?
The homes in Costa Rica are plaster walls with tile floors. No curtains because lizards and tarantulas like to hide in stuff like that.
Sister-in-law is pulling her hair out from the screeching noise -- ALL DAY LONG. I'm thinking about sending a speaker down to them if it can help.
What kind of speaker and room placement would you design in this case?
If headphones no good I would suggest a band limited horn speaker or dipole that covers the speech range with minimum reflections from the hard surfaces.
(I think my wifes suggestion was better 😀 )
Cheers,
Rob.
(I think my wifes suggestion was better 😀 )
Cheers,
Rob.
Do you want a powered speaker (built in amplifier) which connects to the iPad's headphone socket?
A passive speaker driver in a smallish enclosure may work on its own if you choose a driver of high sensitivity.
Since it's speech reproduction that is important, I would roll off the bass and high treble frequencies (like Rob says). This will help keep room interactions to a minimum.
A passive speaker driver in a smallish enclosure may work on its own if you choose a driver of high sensitivity.
Since it's speech reproduction that is important, I would roll off the bass and high treble frequencies (like Rob says). This will help keep room interactions to a minimum.
P.S. Since the iPad headphone output is stereo, two high sensitivity, single cone 4" drivers mounted side by side in the same small enclosure could be a simple solution.
At least two of us in the family said the same thing. I think mom doesn't want to do it because she'd be wearing headphones for hours.
Ok, 4" dipole speakers equalized the way you guys say sounds like a good plan. I don't know how to make a horn or waveguide so I'm wary of that.
Which 4" drivers would you choose for dipole?
Which 4" drivers would you choose for dipole?
Sounds like a case for a bluetooth speaker if headphones are out. You could even have it shipped from a local shop so it gets there faster. Just did a quick search on amazon and the Anker Soundcore 2 is on sale today if that meets your needs.
Sin Phi is on the right track. These days bluetooth speakers are readiy available and they span a wide range of price classes. Bluetooth linkage to an ipad is easy to make and no cables get in the way.
Another possibility is a small desktop set of powered stereo speakers which are available at computer stores or pro audio shops. These speakers have a stereo jack so a Y-cable is needed for the ipad connection.
Another possibility is a small desktop set of powered stereo speakers which are available at computer stores or pro audio shops. These speakers have a stereo jack so a Y-cable is needed for the ipad connection.
Screaming , specially coming from small kids, by definition is high pitched.
Combine that with severely limited tiny speaker in a phone and that´s all you will hear.
Unbearable.
Use basically "any" car door type speaker, say 4" to 6" diameter, inside a shoebox sized box, driven by a small amplifier, say 5 to 15W.
Stuff the box with anything you have available, even cotton or wool or synthetic "thermal jacket filling", not sure what´s your local name for it.
Cut a 4 to 6 cm diameter hole in the back of the small cabinet, to make it aperiodic.
You don´t need deep bass by any means but something flattish from , say, 150 or 200 Hz up.
Such a speaker will provide loud clean full speech, you are doing nothing to kill screams or room noise but you are giving the (useful) rest of the program a chance to be heard.
Combine that with severely limited tiny speaker in a phone and that´s all you will hear.
Unbearable.
Use basically "any" car door type speaker, say 4" to 6" diameter, inside a shoebox sized box, driven by a small amplifier, say 5 to 15W.
Stuff the box with anything you have available, even cotton or wool or synthetic "thermal jacket filling", not sure what´s your local name for it.
Cut a 4 to 6 cm diameter hole in the back of the small cabinet, to make it aperiodic.
You don´t need deep bass by any means but something flattish from , say, 150 or 200 Hz up.
Such a speaker will provide loud clean full speech, you are doing nothing to kill screams or room noise but you are giving the (useful) rest of the program a chance to be heard.
I can relate, my kid is in 2nd grade virtual school due to COVID19 and it's two teachers and 29 kids on a google meet from 8am to 230pm. I finally plugged in an old set of Logitech computer speakers, but modified by putting the 2.5in drivers and amplifier into a foam core stereo BIB. It sounds so much better - warmer, more accurate and less screaming shrill. My kid can hear the teacher better too. Headphones would be great except that we need to monitor what is going on to occasionally help out if needed.
As JMFahey said, and I paraphrase: "a car speaker in a cardboard box stuffed with a T-shirt and cheap 5w amp is all you need." But a sealed fullrange like a PA130-8 in a 6in x 6in x 6in cube stuffed with fiberglass will work great. A $5 lunch money amp will be perfect.
As JMFahey said, and I paraphrase: "a car speaker in a cardboard box stuffed with a T-shirt and cheap 5w amp is all you need." But a sealed fullrange like a PA130-8 in a 6in x 6in x 6in cube stuffed with fiberglass will work great. A $5 lunch money amp will be perfect.
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here's a simple polycone car speaker I liked - might be somewhat mellow for the application (?). - It was mounted in a dipole Karlson type open baffle with rear aperture inverted vs front. I was impressed w. a Beethoven cello (Ax/Ma) sonata and not shabby with opera (1930 recording of Il Trovatore) - power handling was good - used to sell shipped for $13 but now up to near $19 from Amazon. - doesn't have the prettiest power response but probably works as some BSC.
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OP is not here to be sold on a BIB. Any speaker could conceivably be adapted for purpose here. What bradleypnw may find helpful is to learn about listening fatigue, and what helps and harms intelligibility.
I wasn’t trying to sell the BIB if you look at the second paragraph. I simply used the BIB because I had it handy - made it 8 years ago. Probably one of the first foam core speakers I made using cannibalized cheap computer speakers. It does have much more warmth than the little plastic enclosures that it came in. And this warmth reduces the shrill fatigue.
Sounds like the problem is the room, not the speakers.
Band-limiting the speaker to the speech range won't help because an iPad's speakers are pretty much already that so there will be no significant change.
What they need is floor treatment, like a rug, or headphones. Failing that perhaps some carpet covered 'cubicle walls' around the iPad to prevent the higher frequency content being radiated to the sides and back.
Not sure about Apple but on Android with you can run apps which apply a system wide EQ. Notching out the 3-6kHz range and boosting the 200-500Hz range will make voices less sibilant. Maybe they also need to just turn it down. There's a misconception that turning up the volume will increase the intelligibility but often this doesn't hold for portable devices as the speakers get driven into heavy distortion. Better off just adjusting to the lower volume.
Band-limiting the speaker to the speech range won't help because an iPad's speakers are pretty much already that so there will be no significant change.
What they need is floor treatment, like a rug, or headphones. Failing that perhaps some carpet covered 'cubicle walls' around the iPad to prevent the higher frequency content being radiated to the sides and back.
Not sure about Apple but on Android with you can run apps which apply a system wide EQ. Notching out the 3-6kHz range and boosting the 200-500Hz range will make voices less sibilant. Maybe they also need to just turn it down. There's a misconception that turning up the volume will increase the intelligibility but often this doesn't hold for portable devices as the speakers get driven into heavy distortion. Better off just adjusting to the lower volume.
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xrk, I didn't say selling, but pitching an idea. Something that shouldn't be necessary in the DIY part of the forums, as a concept should ride on its own merits.
It's amazing how effective a simple acoustic solution can be!
Passive Amplifiers DIY: How to Make a Wooden Speaker For Your Phone
No speakers, no amplifiers - just a fuller, less screeching tone.
There's a multitude of such designs in the interweb.
First try out the concept using a quick lash-up of a kitchen roll tube and a couple of plastic cups!
Passive Amplifiers DIY: How to Make a Wooden Speaker For Your Phone
No speakers, no amplifiers - just a fuller, less screeching tone.
There's a multitude of such designs in the interweb.
First try out the concept using a quick lash-up of a kitchen roll tube and a couple of plastic cups!
Attachments
P.S. The above illustrations show an iPhone, but the idea is scaleable to an iPad. This video shows how it can be done simply by adding a kitchen roll tube!
How To Make Cheap Loudspeaker For Ipad - YouTube
The kitchen roll boosts the sound from the iPad speaker which is situated at the rear. The improvement in volume and tone can be heard in the video.
If it gives the desired improvement, a more substantial DIY design could be contemplated. Just a bit of fun, but with a purpose! 😀
How To Make Cheap Loudspeaker For Ipad - YouTube
The kitchen roll boosts the sound from the iPad speaker which is situated at the rear. The improvement in volume and tone can be heard in the video.
If it gives the desired improvement, a more substantial DIY design could be contemplated. Just a bit of fun, but with a purpose! 😀
That's interesting. Pretty sure they have tape and paper towels rolls in Costa Rica. A good temporary fix. Maybe even a good permanent fix because you could keep making them as they broke down.