Best tube for SWR

LoveThatBass · Posted: Mon Jan 31, 2005 3:37 pm Post subject: Best tube for SWR

After testing several tubes Here are the ones I came up with in order of preference:

1. NOS RCA Blackplate 12AX7 (by far the best) Punchy, tight low end, very good mids and smooth high end...low noise

2. NOS 5751 Low noise, good headroom, lower gain than 12AX7, Military version good tone, decent lows and mids.

3. Groove Tubes 12AX7M Mullard copy...Punchy tight low end..good tone

Of the above...my first choice is the NOS RCA Blackplate 12AX7. There is no comparison in tone, punch, clarity.

Rufus · Tadpole Joined: 11 Aug 2004 Posts: 22

I use a Sylvania JAN 5751 (D getter) in my SWR.
My fav.

I also like these Fender labeled tubes I bought in the 90's.

I bought a GT12AX7-M (Mullard 'Clone') that was Third Party tested
for low noise and matched triodes out of a batch of about 200.
I really didn't like it at all.

I also like Sylvania 12AX7's for the '70's or early '80's.
They sound warm and smooth in the SWR preamp.

The SWR's really respond to different tubes, more so then
other single tube pre's.

Rule of Thumb: Avoid Chinese Tubes, even though they are OEM SWR.