This is a matched quad when purchased not long ago. They are like in new conditions as they don't have 20 hours on them. I purchased from an official tube store but I don't know where I put the receipt. Sale is for the USA only.
Matched Octet. Matched Sextet. Matched Quad. We all know that swapping out tubes can be one of the more effective ways of improving your tone. At Tonal Tubes, we help you achieve that next level tone.