First the guitar...1981 or 82 Phantom A5.
Some info here:
The Hamer Prototype
Andy Summers used this guitar for the Police "Synchronicity" album.
It has a good LP sound with the bridge HB and a ringing clear sound
with either bridge or neck single coil.
Also has a good "Rosewood FB" Tele sound.
Other players that favor this guitar are Steve Stevens (Billy Idol)
and Glenn Tipton (Judas Priest) who went with different trem systems for it.
Mine is just after the Prototype:
Shown without that goofy looking scratchplate.
The amp is the Cygnus-7 combo.
2x12AX7, single ended 6L6GB or GC for the power tube.
Good, touch sensitive amp when dialed in just on the
verge of breakup.
First I installed both the PM 12AX7's to isolate the power tube tests.
Tube #1: Groove Tubes 6L6GTR grade#7.
Quiet...but kind of cold. Breakup is fizzy sounding...like a broken speaker.
The speaker is a Celestion G12M70, no risk of breakup...so it's a tube
making that sound.
Tube#2: 1960's GE 6L6GC:
Cleaner, more headroom. Adjusted volume for more breakup.
Midrange more pronounced, it started to "bloom" easily
fretting on the D and G strings.
Harmonics noticeably more pronounced.
Tube #3: PM 6L6GC
Volume went down from the GE.
Adjusted again for a bit of breakup.
Distortion wasn't bad like the Groove Tubes 6L6 was,
but it sounded muffled.
Upper midrange was pronounced, but no bloom
unless I really wheeled up the volume...and that is a
result of the speaker reacting to the guitar.
Another thing...the tube was noticeably hotter when
I gave it ten minutes to cool like the others.
Tube#4: Conn 6L6GB (RCA)
Volume output lower (It's a GB rather than a GC).
Clear, very high headroom...the most of them all.
Did not bloom as easily as the GE did.
Nice breakup at twice the volume setting on the amp.
But the animals look scared and my wife came out and gave me a funny look...
(No wonder they used this for an organ tube)!
Tube #5: the other PM 6L6GC
Sounded much clearer than the first one.
Not as good as the GE or RCA, but far better than
the Groove Tubes.
It didn't get as hot as the first PM.
1: Conn/RCA cleanest
2: GE best tone, best breakup, and nice bloom at low volume.
Some people would consider that to be microphonic in high gain situations though.
3: PM #2: Like a cross between GE and RCA, nice sounding tube
4: PM #1: Muddy, but not as bad as
5: Groove Tubes. I already know why they get a bad rep, this confirms it.
12AX7 test in the next post.