Click the link below before buying "so called" NOS AVVT tubes. Old AVVT tubes reach unbelievable prices at Ebay, and it has attracted some fraudulent sellers, which are doing crazy things. Please follow this link when you are interested. Failure Statistics of AVVT Tubes
Repair of defective AVVT tubes is possible, though not offered here at the ex AVVT website. Contact the jacmusic company when you are interested.