Primaluna tube rolling 12AU7 Notes

Thanks for the nice summary.

I use all GE and Sylvania tubes with my Quicksilver line stage and phono stage preamps. If you want to play around with different preamp tubes you should give the Sylvania -Baldwin green label a try! 

Powering horn speakers (Cornwall 4) the Amperex Bugle Boys always worked best in the Evo 400 pre and power - for me. In the gain positions, these tubes more than made up for the mediocre Primaluna tubes in the rest of the positions. Also had the blue bottle Sophia Electric EL 34's in the power tube positions. All good.

Nice summary. Thank you. 

@yogiboy funny, I just ordered 2 matched pairs of Sylvanias from Brent, he has them right now for $40/ pair.  
 

@bolong I also have Sophia’s EL34s.  When I had Harbeth 30.2s I preferred these to the PL stock EL34, but now with the Kantas I like the PL better…not sure why, but it seems synergy always rears its head in these system comparisons.  I think the PL EL34 are a little more fat and rounded at the upper midrange, which works with the Focals.  The Sophia’s have a little more bite to them, dryness perhaps.  Nice tubes though.

These were always average sounding to me. 

Some good info here.

Sylvania -Baldwin green 

I'm also using an EVO400 preamp... but feeding an MC312 into a pair of Totem Fire v2's.  I've found I enjoy a mix of the stock tubes, and gold lions to warm up the sound a bit.  (but not in the conventional positions). Cathode tubes are GL's, and the Gain tubes are 50/50 GL/Stock.  As the kids say: "YMMV".  

Great summary! 
I had Evo 400 preamp, now with evo 300 hybrid with Genalex 12au7. Slight improvement in highs from stock PL tubes, which sound good to me. For new production, what are your experiences? Are those Apos Ray the best? What about new Horizon from psvane? 

as the stated on the page, @noromance,  thats copied and pasted from brent jessee's website https://www.audiotubes.com/12au7.htm

 

I have the following tubes used in my Rogue RP-1:

Brimar CV4003 from Upscale 

Telefunken Medical red tips from Brent 

Siemens nickel / silver plate from eBay 

J&J stock tubes

The stock J&J are very poor, muddy bass, unclear very unremarkable. 
The Brimar’s are wonderful tubes, warm, lush, loving… perhaps a little light on highs. I am surprised the OP described them as a little bass light, as I don’t find them to be so.  
The Siemens are also wonderful but very different from the Brimar’s  They are concise, clear, clean with great bass & sparkling highs. Perhaps the most accurate of my tubes. 
The Tele’s are very good. More forward and perhaps a little bass light (agree with OP). They perhaps are not a good pairing for my Class D Warp 1 amp and/or my KEF R11’s, as people seem to love them. 

My favs are the Brimar’s & the Siemen’s as they are both wonderful in completely different ways. Great rolling. 

 

Nice summary of brands and house sounds.  I concur with a least one minor difference.  I found a black plate RCA to be a real surprise performer.  My main rig is a Willsenton 23 wpc SET integrated amp.  (I know, ChiFi haters, but it stacks up very close against my Cary Audio 300SEI LX-20 running KR 300B XLS super tubes.)  The pre stage is a single 12AX7 signal tube followed by a pair of 6SN7 gain stage to a pair of 300b driving 845 output tubes.  Speakers include Klipsch Forte IIIs and Focal Aria 926.  Source is a fanless silent mini-PC feeding a Denafrips IRIS DDC to a Denafrips Pontus II 12th.   Dedicated power line with true earth ground and hospital grade pure grade copper AC outlets. 

The amp is hot, meaning more than enough power to drive the high-sensitive Klipsch Forte's.  Volume pot 1/4 or less, probably only using 2-3 watts.  I often swap out the 12AX7 for lower gain 5751s and 12AT7 when listening to the Klipsch.  The Focal's handle the full gain 12AX7s just fine.  I have the same NOS brands as Jimmy2615 for 12AX7s and 12AT7s.  5751s are GE, Sylvania and RCA.

GE = good overall balanced linear sound, nothing distinctively great, nothing distinctively bad.  "Workhorse tube," good value. 

RCA = very warm smooth tube with great detail.  Black plate 12AT7 is one of my favorites in the map, particularly with jazz, folk and vocals. Great value for performance. Suprise performer, I paid $12 for it.  First place for a relaxing all day non fatiguing listening experience. 

Sylvania Gold Label 5751 = Like the GE and RCA had a child with the best of both genes.  Clean, clear detail with good linearity.  Nothing extra special (surprised given reviews I've read), but no shortcomings either.  Not as warm as the RCA black plate, but better linearity 

RFT/VEB Rohrenwerk Neuhaus factory = bright, tight, detailed sound with sparkling treble, forward mids and less bass than others.  

Mullard (Blackburn) & Brimar British tubes = what everyone else says, warm lush midrange, good bass but not distinctive and rolled off treble. 

Telefunken ribbed plate and smooth plate = great tubes, linear up and down the frequency range.  Detail, and great soundstage, almost like a loudness button turned on from 20 Hz to 20 kHz. That's a compliment, not a dig. 

Raytheon black plate = Wow, what a great tube.  Superb soundstage, warmth and detail with great bass, strong but not forward midrange and clean, clear treble.  Like a superhero who can do it all. Second favorite of the bunch, #1 below. 

Amperex Bugle Boy = Double Wow! Something very, very special about this Holloand factory tube in my amp.  Matched the Mullard for warmth in the mids, strong structured bass response and a true sparkle on the treble.  Much wider and higher soundstage, superb detail, like a fairy sprinkled Pixi dust in the air.  My favorite signal tube.  

The other thing I've found interesting is the overall sound signature and listening experience is enhanced when matching the signal tube with the gain stage tubes for synergy.  I have several NOS brands of 6SN7s and pairing them with a good match signal tube makes a big difference.  The match is also dependent on music genre and which speakers are running.  

A brighter, more detailed, forward signal tube like the Amperex or Raytheon pair well with the warmer, detailed Sylvania house sound.  The more relaxed Mullard or RCA goes great with stronger more linear and forward Raytheon gain stage.  The best combination for me is either the Bugle Boy or Telefunken paired with Tung Sol mil spec gain stage.  It gives me everything, great fast, deep bass, very warm yet clean forward midrange with clear, sparkling treble and both deep and wide soundstage.  I'd give the edge to Amperex + Tung Sol by a pin.     

Now, if I was stranded on a desert island with only one match, I'd probably go with the RCA 12AT7 black plate with a pair of Tung Sol JAN drivers.  A smooth, linear non-fatiguing sound signature I could listen to 24/7.   

 

 

 

 

 

 

 

 

 

 

@cey Yes. The site I referenced do credit Jessee.

"Special thanks to Brent Jessee Recording & Supply, Inc.for kindly granting Effectrode permission to reproduce the following material below."

Many roads lead to Brent ….. great post and effort by the OP , which in my mind goes FAR beyond a summary….

i rarely visit here…. but this gem of a civil thread will keep me on the line….

best in music

yes, @noromance, as i said, as the stated on the page, @noromance,  thats copied and pasted from brent jessee's website https://www.audiotubes.com/12au7.htm

Great info

Thanks for this post a lot of good information here.

Yogiboy comments;

I have had the same experience that yogiboy has had with Sylvania and GE nos tubes. They are terrific. Many are the military robust ones with a slight variation in the model name/number (JAN). The best brands I have tried are RCA, Sylvania and GE, mostly NOS JAN military tubes.

@jimmy2615 Nice summary - thanks! Which Amperex did you try?

would agree. Nice summary on the input tubes. Almost any tube NOS UOS US or Euro tube is going to be better than the stock 12AU7s that come with the amp. The stock tubes are PSVANE entry level tubes private labeled. If a person is bit more adventurous another quick improvement is to replace the shunt caps on the input tubes with Jensen or Jupiter copper foil caps. The amp will become quieter, more organic sounding and have nicer imaging. Same would be true with the coupling caps.   

@classic8 they’re off labels such as Siemens and Dario, supposedly made by Amperex in the same factory as the bugle boys according to the vendor.  They have shorter plates and are ribbed.  That’s about all I could tell you about them.  

Ok - thanks!

I post this link pretty frequently, but if you want to know where and when your Phillips tubes were made and what tube type you have, you should learn a little about the manufacturing codes. They are etched into the glass on the side of the tube, usually 2 lines of 3 or 4 letters, numbers or symbols. If you look up the link forget about the drawings showing the "Old Code". I don’t think you’ll find any of those. What you’ll usually see is the first 2 "Examples of correct code format" in the "New Code" drawings. This may seem a little confusing at first, but it’s not that hard to figure out.

C:MyFilesWordPerfectPhiltitle.PDF (pocnet.net)

If you have any questions, I’ll answer them if I can.

Interesting, thanks.  Good resource.  I looked at a couple of them.  I would never have seen those tiny numbers etched in the glass.  One I couldn’t find the markings anywhere.  The other one had the little right triangle for the Heerlen factory, looks like 1954 vintage. 

jimmy2615

Thank you for an excellent report on your findings, I too am one who prefers Amperex for my signal tubes (both 12AU7 and 6DJ8). I was lucky enough to stock up about a decade ago, before tubes skyrocketed in price......I certainly could not afford to buy those tubes at current prices......if I could even find them in stock.

I have a bunch of rare tubes, and I use a handful......but I keep most of them in their original boxes. I'll be selling a bunch soon, to buy a nice 300B amp.

I don’t have a PL preamp, only their power amp, the HP dialogue premium, which was pre EVO series. The HP has six 12AU7s plus eight EL34s.  Keeping on topic of the 12AU7s, I have discussed rolling options with Kevin at Upscale, and thus purchased the tubes from him.

His experience, which I confirmed and am in full agreement, is that rolling the middle two tubes are the only two that really make any difference, and boy what a difference they make.

I have two favorites that I switch back and forth between every few months depending on my mood. I don’t know what their current price is, but I paid around $220 per pair about 3-4 years ago.  (When you have a cars worth of money in your system, this is a pretty cheap price to pay for an upgrade)

The first is Mullard NOS- very warm, seductive tube, with big, deep soundstage. Very intimate sound.

The second is the French Cifte-  more detailed. More open on the high end. Soundstage is taller and more forward.

By the way, I am driving Maggies- so I tend to not listen to the low end, and thus have no comments on their bass. But I live for soundstage, warmth and detail.

I have matched pairs of most all of the 12AU7s discussed here, and right now I prefer the new production Apos RAY 12AU7s which come with a warranty and a return period...

RCA Long Black Plate 12au7, RCA Clear Tops, and Brimar CV4003 are my favorites. I use Telefunken, Tungsram & Mazda in the 12ax7 slots - play them in a linestage & DAC and have found MY perfect combinations. 

I just switched from equipment using the 6dj7 line of tubes and Amperex 6922’s are my all time favorites, but I just switched to a preamp that uses 12au7’s. It came with PSVANE, Art series in it and they pretty good. I have since bought from Brent Jesse, some new issue Tung-Sols, some RCA’s (from the 50’s) and some new issue Gold Lions. I gave 100 hours to each set and then listened to the same five songs, twice with each set of tubes. On my system, the Tung-Sol’s sounded great and the RCA’s did have a cleaner and brighter presentation. The Gold Lion’s came in third, but only by a smidgen.
I hope to be getting an in home demo of some Sonus Farber speakers and I’m sure they will require another listening session or three. I’m guessing the RCA’s will be the winner.