The KAV series produced circa late ’90’s was a roaring success for Krell Industries. At the time their product range only consisted of models for the very well heeled. KAV made for entering a market of much greater audience, but to have achieved this the product itself had to be manufactured to a price point. Unlike the KAV series’ cost-no-object brethren some compromises were made to meet targets, the most obvious of which were deployment of economical snap-in type electrolytic capacitors for the main power supply reservoirs. Although there are some advantages to a pool of smaller capacitors such as quicker charge & discharge times, these do not stand the test of time as well as the large format screw-terminal types used in the expensive FPB, KSA & Reference models.
A sure sign of tired capacitors are bulging lids as can be seen below. Often obvious sonic degradation would only set in later and typical symptoms is an audible 50Hz hum coming from the speakers when the volume is turned down completely.
On the KAV series it is also vital to replace the channel rail capacitors since these experience the most extreme heat exposure. Interestingly and perhaps for reasons of superior sound quality, Krell employed Nichicon capacitors in these more critical signal related positions. We however found a specific combination of Nichicon and Panasonic to deliver a very satisfying sonic result. Below are the two re-capped channel rails back in place.
