Tubes work perfectly and sound very nice.

This is a matched pair of Tung-Sol 12AX7 / ECC83 pre-amp tubes. These vintage tubes are perfect for any audio enthusiast looking to add a touch of classic sound to their setup. Made in the Russian Federation, these tubes are of high quality and are sure to impress. The unit type is a standalone unit, and the tube type is a vacuum tube. These tubes are sold as a product type of vacuum tube and are categorized as vintage tubes and tube sockets, vintage parts and accessories, and vintage audio and video. The unit quantity is two, making it a great choice for anyone looking to add a touch of redundancy to their setup.