One problem with the reliability issues with the new Digital HA is they more than likely use RoHS standards which means no lead based solder used in the circuitry. By leaving out lead in the solder it leads to whiskering which shorts out components. Back in the 20’s and 30’s they didn’t put lead in the solder and they had all kinds of problems with components shorting out; this was solved by adding lead in increasing amounts until the whiskering stopped. Unfortunately, we don’t learn from our past mistakes and our unreliable electronic devices are living proof of it. Just one possible reason for unreliable Hearing Aids.
The overwhelming majority of failures in hearing instruments are the receiver and the mics, which will be in both analog and digital instruments. The failure within an integrated circuit is extremely rare.
Zafdor is right.
Digital aids with everything on a sealed chip should be more reliable than old fashioned analog discrete components and just as reliable as a chip based analog. Anyway most failures of all aids are due to moisture/sweat or abuse. Most often it’s the transducers or the battery doors that fail and that’s the same whether analog or digital.
Incidentally, TV failure rates dropped precipitiously when they switched to chip based architecture. Ed
You are ignoring seb’s comment. The issue is not likely within the chip but the soldered connections to the chip and other components.
seb said " Just one possible reason for unreliable Hearing Aids".
I have seen others talk here about sweat related failures as ed121 mentions.
This echoes what I think has been my biggest complaint regarding HA failures.
I’m sure both opinions are valid.
One thing I failed to mention about the whiskering issue is it seams to happen faster in moist environments so HA are going to have more problems due to operating in a moist environment.
my digital hearing aid well my 3rd set of them has very good realibilty cause one, they’re good with music and BG around me. 
I have Oticons btw.
Can you post a link to whiskering being a problem with lead free solders? I have never heard of that. Lead free solders do require higher temperatures and that can be a problem with some components. An analog instrument will have at least as many solder points in the hearing instrument as a digital one so at the end of the day I still see no reason analog instruments would be more reliable.
This link might pertain to seb’s comments?
There are no shortage of articles on the web regarding whiskering.
Here’s the search terms I used “whiskering being a problem with lead free solders”
Damn! I’m getting dated. I didn’t know they were using lead-free solder in aids.
What ever happened to the silver soldering technique? I don’t remember it growing whiskers.
Just a little ancient history. When I was working my way through engineering school, I worked part time at an aircraft radio manufacturing plant. My job was to inspect each lead soldered connection in the radios and dab it with red paint. No whiskers there. Ed
Environmental concerns mandate the change to lead-free solder :mad: and planned obsolescence…
Environmental concerns mandate the change to lead-free solder :mad: and planned obsolescence…
Yet states are mandating the use of compact(mercury filled) fluorescent bulbs…go figure!!! which one will be found more readily in a landfill hearing aid or light bulb!!!
Not to mention lead and mercury are natural elements of the Earth. What lead you have now is what you will have in the future. The problem is we don’t learn from our past mistakes; we went down the road of whiskering in electronic components in the 20’s and 30’s and found out how to stop it and now the environmentalist are causing us to go down the same road again!
Could you post links to support your theory:D
Alpine,
What I know about whiskering and the electronics of the 20’s and 30’s was told to me by several electrical engineers I know and I’ve read several articles over the years about RoHS compliance and the problems the U.S. military and Govt. is facing regarding weapons and other vital electronics shorting out do to whiskering. As for HA if they are sold in Europe you can bet they are RoHS compliant which will lead to premature failures and you can also bet they aren’t making aids just for the U.S. market that has lead solder.
Well, I’m still waiting to hear back from our whiskering expert on the lead free solders, but even if there is whiskering, there are simple ways to deal with it in hearing aids & most electronics.
Care to share with us how?
We call it overfill in the company I work for. It is basically potting material, designed to get under the die and between even fine pitch solder ball attachments. It also makes repair and rework impossible.
Zafdor,
I don’t claim to be an expert on whiskering all I know is what I’ve read and what I’ve been told by several electrical engineers I know. You say there are simple ways to deal with this issue in most electronics, then why aren’t the manufacturers using these simple things? I know someone who repairs flat screen TV’s and he has them lined up like cord wood all with whiskering problems which are to costly to repair. Most of these TV’s are less than a year old! If these wizards who know how to stop this problem are doing it, they need to come up with something that actually works! What are these simple solutions and how long do they work? 6 months? 1 year? Just past the warranty period? I would be interested in knowing.
I don’t think digital aids are as reliable as analog aids. The more bells and whistles they contain, the more likely they are to fail. Plus, the chips they use are all made in China or Hong Kong, so who knows how good the quality control is? Analog aids tend to be more robust and reliable, which is why I prefer them to digital aids. What good is spending thousands of dollars for digital aids if they spend most of their time out for repair? This is just insanity. Gerald
Modern digital technology is very reliable. Extra features are implemented through software or chip design changes, so there is no reason that a more advanced aid will fail faster. Possibly analogue aids are more reliable - but that’s probably because they tend to be large and built like a tank. A modern digital aid in a heavy housing would be equally reliable.