does t4b´s get bad over time?

[Larsson]

Hi folks.
I got my hands on a old Urei la3a. It compresses and does its job but hasnt got the "wow" factor i remember from using la3a:s in the past.
My question is if I should try and swap the t4b?  Its the original t4b inside and I would of course like to keep it.
Any insights on this? Do they get old/bad and needs to be replaced?
Thanks // Larsson

 

[CJ]

yes the EL panel will slowly change, light output per volt will decrease,

LDR cells might change a little but probably not nearly as much as the EL panel,

they use phosphorus to make the EL panels and it wears out,

 

[squib]

LDRs can degrade and indeed fail. Symptoms of degradation can be significantly higher levels of distortion and occasionally less than the required Rmin for a given illumination.