[shaler78]

I have a Philco 47-1230 with two 6V6 tubes used for P-P output. Are any manufactures tubes better than others to use in this set to achieve better sound quality. I am currently using two RCA tubes that sound pretty good. Is there any difference in sound quality between different manufacturers, and is there any real difference between new more modern tubes vs. NOS or tested good old used tubes? I was looking to buy a full replacement set of tubes, new or used, for this chassis as eventual replacements. This set has a 9 tube compliment using 1-5Y3GT, 2-6V6GT, 1-7R7, 1-7X7, 1-7F8, 1-7AF7, 1-6AG5, and 1-6BA5. Thanks for any suggestions.