Short version:
☝title, something that can be clipped onto scrubs or worn around the neck. Also easy to clean - hard surfaces that can be wiped down with alcohol, no cloth coverings or anything.
Long version:
Nursing student here. Basically I’m trying to build a stethoscope that doesn’t need to be inserted into my ears.
I have some hearing loss, and currently use hearing aids, which has posed a frequent annoyance / hazard at my clinical rotations when it comes time to listen to my patient’s heart and lung sounds. I can’t use a normal stethoscope with the hearing aids in, cuz it shoves them way too deep into my ear canal (doesn’t feel great); so I’ve just been popping the fuckers out and using the stethoscope normally when needed. …but I hate doing that, cuz hospitals are disgusting - there’s literal and metaphorical shit on everything, so screwing with the hearing aids mid shift is 100% introducing pathogens into my ears.
At my last clinical site, one of the nurses had a bluetooth stethoscope that seemed like the miracle solution I needed - it’s basically a stethoscope bell with no tubing, and it pairs with bluetooth headphones. She let me try it out, so I paired it with my hearing aids, and… heart beats sounded like two pieces of metal clanking against eachother. Total flop, clinically useless. Fuck.
So I whine to my audiologist, and eventually we figure out that the issue is that heart and lung sounds range from 20-100 hz; and my hearing aids are designed to amplify human speech, which is about 300-3000 hz. The speakers in my hearing aids are not physically capable of playing heart and lung sounds (that clanky metal sound was just the tiny bit that overlapped with the hearing aid’s range). More fuck.
So, I don’t think my hearing aids are going to be part of the solution here, but I’m still seeing potential in the bluetooth stethoscopes: but instead of pairing it with bluetooth headphones, since again the ear canals are already occupied, instead pair it with a bluetooth speaker that I can clip onto my scrubs or use the kind that hangs around the neck.
Poking around the internet, there are tons of those types of bluetooth speakers, but they never seem to advertise the hertz range and I’m worried about getting a whole setup built, then running into the same issue with the new speaker not playing the sounds I need to do an actual nursing assessment. And those bluetooth stethoscopes are expensive as fuck, so if I’m going to dive in to this, I want to make sure I don’t screw it up.
What do you all think? Any brands or specific products you’d lean to?
Also, bonus question: putting yourself in the patient’s shoes: how would you feel if your nurse dropped in rocking a setup like this? If it’s playing through normal speakers, YOU the patient would be able to hear your own heart and lung sounds during my assessment - my thought was it’d be great for patient education: “That clicking sound when you exhale is called crackles, which means there’s fluid in your lungs, so…” Would that make for a decent patient experience, or be offputting or intimidating? I’ve been a surgical tech for like a decade, so my perspective is pretty skewed in terms of how much info is too much info.’
Thanks all!
Rtings.com provides frequency response charts when they test speakers, let me see if I can find one that goes low enough for you.
As for the bonus question, absolutely love it. I love when people come up with cool solutions to life’s problems, and this lets me hear my own heartbeat? Hell yeah!
Here’s an easy way to check a bunch of them quicky, the Denon home was the best I found in terms of the very low end. I’m sure someone else can do better, I’m not that much of an audiophile and know very little about speakers.
Probably worth noting that they stretch out the low end of the chart so they tend to go lower than it seems (I assume it’s a logarithmic scale). You might be able to go to a store and ask to test them yourself.
Second edit: if headphones are at all a possibility (they might be better for patients who don’t want to hear their own heartbeat) then can I recommend Skullcandy crushers? They’re completely ridiculous as regular headphones, they basically just have a metal plate they vibrate for the bass, but it goes all the way down to 20Hz, and you can crank it waaaaay up with a slider on the side. (I use these daily for music because I’m a bad audiophile who wants to have fun sometimes, I have a proper wired setup if I want the audiophile experience.)
+1 the crushers. I’m not sure of anything else that currently exists that would get down to those low frequencies without being annoying or expensive
Thanks!!
Looking at those graphs, I’m assuming amplitude in that 20-100 hz range is ideally as close to that center line as possible? Seems like most options are very low on that range, but not completely absent - how low would you say is too low for a project like this?
Like that Denon in your second link, 20 hz is showing at about -17 on the amplitude axis, is that audible?
Definitely not going to rule out headphones, as those might be the best option; but my main hangup there is bulk, and needing to actually handle it with each use. Part of why I was leaning toward those hang-around-the-neck bluetooth speakers is the thin profile and that I can just leave them on and paired with the stethoscope - then the only thing I’d have to handle is the stethoscope itself. Minimizing actually touching it is definitely a priority… can’t stress enough how nasty hospitals are!
I’m afraid I can’t answer your technical questions, I’m really not that knowledgeable about this. All I know is you ideally want the frequency curve to be flat, I don’t think it matters much where it sits relative to that line.
Honestly, that Danon dropping off at the low end is pretty typical though it’s one of the better ones. You’d really just have to test it I’m afraid, it might be totally fine to chop off the bottom for some things but maybe it’s necessary for certain heart conditions, I wouldn’t know. If it were an option I’d say the best bet is to always stick to the analogue, but I’m absolutely with you on hating traditional stethoscopes, they’re so painful…
You probably can just leave the crushers on your neck with the volume maxed out, but I’m really not sure if that’ll work. In all honesty the speaker might be worse due to the way the acoustics in the room can change what you hear, it’s really hard to say.
Yes, you want to find a speaker with a flat sound signature.
This is a type of speaker called “studio monitor”.
Remember that sound is very unforgiving when working with it, every single step in the chain of recording a sound to playing it back can change how it sounds, with the changes to the sound being compounded when you play it back.
This includes the microphone, the microphone amplifier, the speaker amplifier and the speaker.
This does not mean that it is impossible to do what you want, but be prepared that the sound may sound strange from what a normal stethoscope would produce.