Capacitor burn-in
The subject of burn-in time for audio capacitors is a widely discussed topic, often sparking heated debates between believers and non-believers.
We have done our own tests and exchanged opinions with a wide range of speaker designers on this interesting subject.
It is our finding that there is no audible change in the characteristics of our capacitors over time, at least not to a degree detectable by most human ears.
It is also our opinion that unless we are talking about aluminum electrolytic capacitors or other capacitors types that contain dielectric fluid, oils, or any other liquids that can evaporate over an extended period of application, a capacitor will not change its physical characteristics or properties in any way that will make it sound “different” or “better” over time.
We have also had discussions with veteran speakers designers and based on a numerous number of feedback reports, the consensus seems to be that even after hundreds or thousands hours of using a speaker system, the sound or performance of capacitors do not change to a degree that can be heard by the human ear, unless we are talking about defective capacitors or capacitors that have changed their capacity due to evaporation.
When it comes to “burn in time” or “play in time” there is a consensus about it taking place for e.g. bass or mid-woofer speaker units, where the fabric outer suspension and/or fabric spider often becomes softer over time and reduces the point of resonance.
Light-weight non-treated paper cones may also become slightly softer over time and change properties.
Such changes can indeed have a very noticeable impact on how the speaker system will perform and here we can truly have a consensus that play-in time is needed to get to the point where the speaker system is performing at its full potential.
The mental burn-in time
We think it makes much more sense to talk about what can be described as a “mental burn-in time”, where your ears and hence your brain will need time to adjust and reflect on the change that has happened, when listening to a speaker that had new capacitors or other components exchanged.
When it comes to swapping / upgrading capacitors or other components it will always be a matter of taking some time to get used to something new having happened.
After having listened to many types of recordings and even from different media types for a longer period, it is completely up to the listener to determine if the change is a preferable thing or not and perhaps discover that less is more.
Doing conventional A/B listening test with a switch between different capacitors, is asking an awful lot of our ears and brain.
After a short time, all the impressions become muddled, and we end up more confused than enlightened.
It is our opinion that a more effective A/B listening test is to make a setup “A” and listen to that for an extended period and then do a setup “B” and do the same.
Then return to setup A again to see how we feel about the differences between the two.