Amps are in perfect original working order and sound as good as they always have. No upgrades have been performed on them. Email email@example.com with any questions. I accept PayPal via the same and payment is expected prior to shipment. This pair will need to be retubed with a quad of EL34's, a pair of AT7's and a pair of AU7's. While Thor Audio is no longer in business the amps are serviceable by any quality electronic technician. Parts still readily available.