Here's the review I posted on Amazon
back in April of 2007, shortly after I bought my Thinklabs ds32A:
As a degreed Chemical Engineer for 22+ years, and a volunteer Paramedic since 1991 (in my "copious free" time), I wanted to treat myself to a new stethoscope prior to starting an accelerated BS-->BS/MSNursing program in a couple more months.
I chose the Thinklabs Rhythm ds32a stethoscope.
I've used a Littman Classic II SE scope for the past 5 years or so, and have been happy with its performance (no breakages, nothing worn out). I looked at other electronic stethoscopes, but they all seemed pretty expensive.
The Thinklabs scope is well thought out. The company president, Clive Smith, is a degreed Electrical Engineer. Although he didn't choose the "one true path" of Chemical Engineering, I won't hold that against him (too much!).
I have only been using this scope for a month or so, so I don't have years of experience in using it (yet). It is not heavy at all, and is comparable to my current scope. It has a nice shiny chestpiece (chrome plated aluminum), and soft earpieces, which block out lots of ambient noise. LEDs on the reverse surface of the chestpiece show the current "operating mode" for the scope. Amplification is adjustable via an "all or none" control, and a "volume" dial.
The biggest selling point for this scope (in my humble opinion) is the "fly by wire" design, meaning that it's totally electronic from chestpiece to earpiece speakers. Most amplified scopes have a normal style (acoustic diaphragm) chestpiece tied to a hollow rubber tube leading to the electronic amplifier. With the Thinklabs unit, the chestpiece is not a normal acoustic diaphragm. It is a metallized diaphragm in front of an electronic transducer (~2" diameter brass disc). This picks up sound vibrations as with "old fashioned" scopes, but rather than just dumping sound vibrations up the long rubber tube, it sends the signals via wires to the amplifier "guts" located about halfway between the chestpiece and the earpieces.
THINK ABOUT IT...rather than the sound being mixed with ambient noises picked up by the floppy rubber tube, the Thinklabs unit sends the sounds directly via wire to the amplifier, avoiding a lot of the ambient noise.
Once signals leave the amplifier, they're directed through wires to neodymium magnet speakers in the earpieces. Once again, there's not a lot of opportunity for ambient noise to interfere with whatever signal the chestpiece picked up.
I have used this stethoscope in the back of an ambulance running lights & siren, on noisy Dayton, Ohio streets. It blocked out most of the ambient noise, and still allowed me to still hear decent breath sounds. That's pretty impressive! In a quiet home or hospital setting, this scope is bound to be ideal.
TWO MINOR COMPLAINTS -
1) The unit doesn't drape across your neck & stay in place as well as the Littman stethoscope. I find that the earpiece end of the scope tends to slide down your chest. Not sure if that end is heavier than the chestpiece part, but it's still a bit irritating.
2) The shiny aluminized plastic battery compartment worries me a bit. I just wonder how well it will handle normal wear & tear without rubbing off the shiny coating & showing the black plastic underneath. Thinklabs says it's polycarbonate, which should be nice & tough, but with a scope this expensive, I'd hope it stays nice looking after a few years of use.
For EMS field use, I'm still reserving judgment as to this scope's durability. As an electronic device, it's probably not as "bullet proof" as an old fashioned acoustic stethoscope. I've not used it outside in the rain yet, so I can't speak as to whether the electronics will hold up. The president of Thinklabs seems very willing to back up his product, and answered my emails directly. This is very unusual in today's business climate, and speaks very well of the company's willingness too back up their product.
The ds32A also comes with an adapter cable which allows you to record sounds picked up by the stethoscope. I've not played around with that feature yet, but it would be ideal for teaching.
If you're looking to buy an amplified stethoscope, I'd give this one some serious consideration.
UPDATE RE: HEARING IMPAIRED USE 7/30/08:
A member of my nursing class had Cogan's Syndrome (weird autoimmune disease nuking her hearing). I loaned her my Thinklabs ds32A for a trial, but think she ended up with a different stethoscope. I've emailed her & asked which 'scope she ended up using.
In emailing my classmate, she wrote:
"I finally went with the Cardionics E-scope with the traditional binaurals....I chose this one because it offered the most amplification, which I really don't need much right now, but the way my hearing
fluctuates, I likely will need considerable amplification down the road. Also, it was the brand I heard things most clearly with."