Hi and thanks for the 'funken suggestion!   Best 12ax7's ever made???  Definitely NOT!  What sounds the best in one circuit to a person's ears will not sound the best in another circuit to that same set of ears.  Even more so when considering the amp families that are represented under the Ceriatone banner.   Marshall, Fender, Trainwreck, Dumble, Matchless, Hiwatt, etc.  Each family has it's own type of voice.  For instance, RCA 7025 shortplate is THE classic V1 Fender tone tube.

I have a few TFK smooth and ribbed plate 12ax7's and a few 12at7's as well.  I know what you mean about the sound qualities of the smooth plate, they have great control over their harmonics when overdriven, and are more compressed and smooth sounding than most 12ax7's. 

Similarly, the ribbed plate versions are also compressed when pushed, have excellent control over harmonics, and tend to have more top end to their tones overall than the smooth plate version, both types do the smooth sounding violin type sustain VERY well, the smooth plate will take more gain before it starts to get a bit bright on the top end edge of the tones and that takes serious amounts of gain to ever get there.   Thinking about that, I could easily see where a smooth plate might give up a tone through a c-lator that would be reminiscent and supportive of the original OTS, while a rib plate might give up the kind of tones toward the direction that the HRM's are known for.  I will definitely remember to try both types out! 

And in the FWIW department, their 12at7's are simply gorgeous sounding clean or dirty, and i have some very top end at7's to compare them to.

We are building a very nice and special thread, so please keep the posts coming.  Good things are here because of YOU! 

Cool!  Great to hear from you!  Amperex 12ax7's are one of my fave pre's.  They are brighter than Mullards most of the time in the shortplate version. 

Thanks so much, and please keep the suggestions coming! 

AWESOME!  Now we're talkin! 

I have examples of all the tubes you suggested except the JJ for the PI slot.  I do have several VOS Tesla ecc803s/e83cc, forbears to the JJ.  They are smoother with more harmonic content, they make wonderful copies of the signals coming from earlier in the tone chain. 

More suggestions are welcome!   Saweeeeeet!   

Thanks!  I have some EI's, both gray and "silver bullet" types.  Will roll a grayplate when the amp shows up, guessing that will be in January sometime, since the order date was Oct 28th. 

FWIW, it's best to refer in print to modern production Tungsols by placing the "RI" (re issue) suffix after the tube name type, as in Tungsol 12ax7 RI.  The ones made today are in no way similar in build or tone to the originals. 

The originals are warm, fat, smooth, and gorgeous sounding, lots of detail in the lower and upper mids, they would go well in a slightly too bright amp for instance. 

Yep, the folks here are kind for sure.  Also that way on the Heritage guitar owner's forum.  Not a big fan of the HC forums, they are out of control in not a good way. 

But back to the original post, if there are any vintage preamp and/or power section tube faves that you have enjoyed in a 50w HRM I'd be interested in what and why the selections you tried were pleasing to you...

and thanks to all!!

Wow!  Thanks for your replies, the welcome, and the civility in your words. 

On the Champ thang, that's how I currently evaluate my tubes.  I like the tube roller thang, but I already have a testing unit that works well. 

And yes, NOS tubes are too expensive.  Plus they frequently don't sound as good as well broken in ones, too bright and brittle.   I buy mine as VOS (vintage old stock) USED, and frequently for prices not much more than new production units...on eBay.  Have picked up Amperex, Siemens, and Mullard long plate 12ax7's for easily less then 40 bucks each that way, for instance.   That's not too expensive. 

I have a Hickok Cardmatic and test them in it, mark results on the bottle, and then roll them one at a time in a single ended amp.  It's a silverface Champ, has no Fender parts anymore except the power switch, the light, the pots, and the cab.  I populated a blackface turret board with tantalum resistors, F & T electrolytics, Black Gate cathode bypass caps, Jensen copper foil PIO tone caps.  The PT is oversized, the OT is a monster sized 5k primary 30 watter that had to be mounted in the bottom of the cab with t-bolts, am using the 16 ohm tap.  The power tube socket has pins 1 and 8 connected, so I can and do run el34's, kt66's, and even 6550's in it, plenty of filament current available for the heaters from the PT.  Then I lifted the 10k resistor from the bass pot going to ground.  The ground is now a bus rather than the chassis.  The gain as a result of lifting that bass pot ground is pretty monstrous.  The tone controls don't really work anymore, the bass pot has no effect, the treble very little, all the way down sounds more mid scooped, all the way up is more mid focused.  So get a good palette of tone from clean to scream.  Easy to spot  a microphonic tube in that setup too. 

First time Ceriatone owner here, waiting for a new 50w HRM to arrive.  I have a couple hundred vintage 12ax7's, (almost any kind that have ever been made,) and a decent variety of 5751's and 12at7/6201's. 

For the power tubes I have some vintage 6l6g's, 5881/6l6wgb's, vintage el34's by Siemens and Tesla, a couple pairs of GEC kt66's, a few pairs of Bendix 6384's and adapters.  Also picked up a pair of TAD short bottle 6l6gc's. 

I am expecting some excessive brightness for the first hundred hours or so until the caps form and the OT seasons.  To be honest, I won't want to stick any modern production preamp tubes in it...

Am interested in your tubing suggestions, and reasons why they work for you.  I have a few Heritage brand guitars, all have humbuckers.   Frankly I'm surprised at all the posts about circuit tweaking and conversely so very little from the tube selecting/bias setting side of amp voicing. 


Thanks!