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Old 15th January 2010, 09:27 PM   #1
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Default EL84 Unused pins safe to connect?

Some of the pins of the EL84 are shown as IC (Internal connection I suppose).
Is it safe to use these as tie points?
Here's an example: The Hazen mod uses the separated suppressor connection on pins 1 and 6 of the SV83/6P15 but these are "IC" on the EL84 datasheet. If I build an amp with the Hazen-enabled 6P15 and then want to use an EL84 (I know the Hazen won't work with EL84) in the same circuit, do I have to unsolder the connections to pin 1 or 6?
Don't want to damage my precious NOS Philips EL84s
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Old 15th January 2010, 09:32 PM   #2
SY is offline SY  United States
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Is it safe to use these as tie points?
Generally not. If a pin is safe to use, it will have an NC as a code.
"The way to deal with superstition is not to be polite to it, but to tackle it with all arms, and so rout it, cripple it, and make it forever infamous and ridiculous."- H. L. Mencken
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Old 15th January 2010, 09:37 PM   #3
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Greetings from FixitLand!

Caveat on using 6BQ5's in modern EL84 amps!

I would leave pins 1, 6 and 8 open. In fact, I *did,* in my "AMP II." That way, I can use a 6BQ5/EL84, 7189 or 7189A interchangeably.

Take care,
J. E. Knox 'The Victor Freak'
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Old 15th January 2010, 09:42 PM   #4
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Thanks, Sy. I'll have to try and remember to unsolder them when I finally knock the 6P15 Hazen version up. I currently have the EL84s in stereo SE driven by a 6N3P-EV and it sounds very nice, and wanted to try 6P15-EV with Hazen mod for comparison.

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Old 15th January 2010, 09:49 PM   #5
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Thanks rojoknox. Interesting post that, especially cutting the pins off the tube. Yikes!!
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