Tubes
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| 7591 Output Tubes Tubes are tested using a Calibrated Hickok 6000 Mutual Conductance Tube Tester |
| Sylvania USA 7591 Matched Quartet These also came from McIntosh Labs. They are a fully matched Quartet and test at 5150 in reference to the 5100 standard of the Hickok 6000 tester. 249.00 |
Avid Audio
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| McIntosh Matched Quartet 7591 Tubes 139.00 SOLD |
| McIntosh Matched Quartet 7591 Tubes This is a full set of matched Westinghouse 7591's. They tested at 4800 using the 5100 reference on the Hickok 6000. Other than a few marks on the bakelite bases as shown, they are in excellent shape. 189.00 |
| RCA USA 7591 Matched Quartet Tubes These came from McIntosh Labs many years ago. Westinghouse manufactured these for RCA. The RCA 7591's are NIB. 299.00 |
| RCA USA 7591 Matched Quartet Tubes All four have the coin base like this one. Removed for picture and testing. SOLD |
| Philips USA Matched Quartet 7591 Tubes These are NOS tubes from Philips USA. The writing is smeared somewhat but they are new and tested at 5150 on the Hickok 6000 tester. 239.00 |
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