minimum 12AX7 tube spacing

[tubenit]

Guys,

I'm still debating whether to go with an onboard active effects loop with my other Tweed Overdrive Special or make an outboard one.  Trying to see if onboard would be an option at all.  The FX tube in my other TOS works excellent.

As you can see from the photo, it would be a VERY tight fit (1.75" spacing)  but perhaps do-able?

Think I can make the FX tube fit in there without noise or oscillation issues?

With respect, Tubenit

[FYL]

The empirical rule is > 1.5 tube dia. The 12AX7 measures .8" => 1.2" min. 1.75" should be OK.

[tubenit]

FYL,

Thank you for the response!  It is appreciated.  That allows me a reasonable option then.

With respect, Tubenit

[Fresh_Start]

Not necessarily applicable in this case because you're shoe-horning an extra tube in, but isn't there a particular orientation 12AX7 type tubes are supposed to be in?  IOW isn't there a certain way they should be lined up to reduce noise/interference?

Cheers,

Chip

[tubenit]

isn't there a particular orientation 12AX7 type tubes are supposed to be in

I've never heard that before. I've done quite a few builds & have never paid much attention to using a particular orientation. To the best of my memory, I have not been aware of it making a difference?  Maybe at times, it can matter.

With respect, Tubenit

[echuta13]

I've seen some discussions recently on which triode is quieter in a 12ax7 which might affect orientation...  Other than that, I only thought that orientation mattered on tubes with significant radiant heat output.