03-13-2026, 04:41 PM
Hi Ken,
To get the 1A5s to work well, you need the 25K transformer. If you can get 1Q5s, consider getting them and undo the 3Q5 mod. The reason is that the original tubes for this set are likely the longer, skinner "G" versions as opposed tom the shorter, fatter GT versions. 1Q5s are available in the G version, if you are looking for an original look. This way, you can switch to the 1A5 for display or the 1Q5 for performance.
These tubes were developed by Sylvania , who was the OEM supplier for both Philco and Zenith
To get the 1A5s to work well, you need the 25K transformer. If you can get 1Q5s, consider getting them and undo the 3Q5 mod. The reason is that the original tubes for this set are likely the longer, skinner "G" versions as opposed tom the shorter, fatter GT versions. 1Q5s are available in the G version, if you are looking for an original look. This way, you can switch to the 1A5 for display or the 1Q5 for performance.
These tubes were developed by Sylvania , who was the OEM supplier for both Philco and Zenith
"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
"Let us begin to do good"- St. Francis
Best Regards,
MrFixr55
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