Description

Contrary to popular belief, the 5963 is not an automatic drop in for all 12AU7 circuits. I suggest contacting the manufacturer to be sure. All tubes come with a full 30 day, unconditional, no questions asked, money back satisfaction guarantee! Test scores will average 85% to 90% of NOS values. Individual test scores will be written on the new boxes that you receive with your tubes. You are purchasing a "Platinum Grade" tube. This means that the plates are very tightly matched on a calibrated Hickok 799 within 5% Please see our other listings for "Silver, Gold and Platinum Plus" tubes. Silver Grade tubes are matched within 15%, Gold Grade tubes are matched within 10% and Platinum Plus 1% . The Gold and Platinum tubes are recommended for more critical applications such as your preamp and phono stage. Please email with any questions and/or concerns. Thank you for viewing my listing.