VTA ST-70 Power Tube Socket Upgrade

Originally, the amp had poor quality power tube sockets. They were also flushed with the top surface of the chassis, causing the socket mounting screwheads to protrude above the chassis and socket. It could only fit narrow base power tubes. Here are some pictures showing the original flushed-mounted power tube sockets.
VTA ST-70 amplifer

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A wide base power tube would sit directly on top of the mounting screws, and not be completely seated in the socket, as shown in this picture.
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This causes the amp to pop and short out the 3A fuse. One could carefully and firmly seat the power tube, but it was a crap shoot. It may not work, causing rectifier tube damage. It may work for a while, but eventually a power tube would work its way up / out, causing rectifier tube damage. This causes expense in the form of fuse and rectifier tube replacement - gotta pay to play! I took the amp to my trusted tech, who also worked on my McIntosh amplifiers (authorized). He replaced the power tube socket, and checked everything else out. It was healthy. Additionally, the tech also pointed out the poor quality of the original sockets. With previous tube rolling, the sockets have been loose and made poor contact. This is the reason they sell "socket savers". It's cheaper than replacing sockets. This is what socket savers look like:
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The previous poor quality power tube sockets.

These pictures show the new, better quality, better designed sockets, with wide base power tubes (KT88 Coke bottle):
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The amp now has better power sockets and has been given a clean bill of health.

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