What's A Good Upgrade From A Manley Steelhead?

@rooze  : I can see that you are way demanding with that " bass " in the PS Audio unit.

Fremer was using the WA  ALEXX paired with Dartzeel Monoblocks and top of the line Dartzeel phonolinepreamp, no tubes at all an in true high resolution system and I think that the Stellar made a great job down there that any Allnic/Manley/VAC or tube unit can touch it.

As the Dartzeel or the CH the PS Audio phono stage is not perfect but for the " huge " 2.5K price tag you can't ask for more.

R.

While someone else mentioned that the Steelhead uses a transistor per channel as a constant current source (CCS), it is my belief that the amplification stage is actually a hybrid cascode, with a transistor serving as one half of the cascode circuit.  Using a cascode, to my knowledge of tube electronics, is the only way they could be getting up to 65db of phono gain.  It is also possible that the cascode is derived from single sections of two of these high transconductance dual triodes, with the transistor serving as CCS only.  But since Manley do not release a schematic to anyone, this is pure speculation.  What is not speculation is that you cannot get 65db of phono gain with merely a 6DJ8 type tube.  I think it's a cascode driving a White cathode follower (mentioned by Evanna Manley in the 6Moons article) which drives either the attenuator, if you use it as a full preamp, or driving the external linestage. If output goes through the attenuator, then the attenuator drives yet another White cathode follower, which drives that output.

@rooze 

Here's a good summary of the 6922 tubes from Brent Jessee Recording and Supply:

OK, SO TELL ME HOW THEY SOUND!!

A tough question if there ever was one! The best advice is to get a few types and hear for yourself the good sounds you have been missing. All of these vintage tubes are excellent, much better than the Russian or Chinese yuck that is being made today. When replacing any stock Russian, Chinese, or East Europe tube with any of these vintage NOS types, you will notice immediately that the midrange glare is gone. Gone too is that honky, boxy quality, and the tiring upper midrange screech that current production tubes are famous for. Here are some VERY GENERAL observations about some of these vintage tubes:

TELEFUNKEN, SIEMENS, VALVO, LORENZ, and other German made NOS: These tubes are usually characterized by an impressive open "air" at the top end. The soundstage is large, even in mono applications these tubes have a great 3-D image. The midrange is ruler flat, and the bass is tight and accurate. These tubes have a fine sense of dynamics, and most are impressively quiet. These are not "warm" tubes, and to some ears their lack of midrange warmth may be heard as bright. I tend to think of them as accurate, and their clean, focused sonic image is astonishing. My personal favorites. The top types are as would be expected: the 7308/E188CC, the Cca, and the 6922/E88CC. The Cca is a very special 6922 made for the German government for telecommunications. They are excellent tubes, as good as any 7308. By the way, the 1970s versions of these brands are excellent as well, in spite of some trashing on "Some Guy's Tube Lore" and other web pages. Don't let anyone tell you what tubes you should like and what you should not like!

AMPEREX, PHILIPS, MAZDA and other Holland/France/Belgium made NOS: These tubes are a great balance of a clean, airy top end, nice midrange warmth, and accurate bass. They are very pleasant, clean, and musical to listen to in hi-fi applications. The white label Amperex PQ type or USN-CEP (same tube, the USN was made for the military) made in the USA are considered one of the best 7308 or 6922 types of all ever made. The D-getter and pinch waist rare types are also highly regarded, and are very quiet as well. The orange label types run a close second. Look for the white label USA and Heerlen Holland factory made for other brands. They are the same tube and usually less expensive than those with the Amperex or Philips label! Finally, Philips (the parent company of Amperex) owned a number of tube brands, and many were never seen outside of Europe. Most were actually made in the same Heerlen, Holland factory that turned out the Bugleboy 6DJ8 and PQ 6922 Amperex. Watch for tubes labeled E88CC with brands like Valvo, R/T, RTC, Miniwatt, Dario, Philips, and Adzam. These tubes are identical to the Amperex PQ and Philips SQ (Special Quality) types more often found in America, and are perfect if the Amperex is not available, since they sound and look the same. Also rare in America are these same brands made at the Philips-owned Mazda factory (La Radiotechnique) in Suresnes, France. These usually have a capital "F" in the second line of the date code. They are sweet like the Holland tubes, with a bit better detail and punch at the top end, and still have nice balanced warmth. We are one of the very few worldwide tube dealers to offer these rare NOS French Philips tubes.

MULLARD, GENALEX, BRIMAR, and other British made NOS: Like a warm British jacket of the finest tweed, these glorious tubes have an attractive sweet warmth in their midrange and lower regions. The top end is silky and pleasant, without being rolled-off. The best of these tubes retain a fine sense of "air" at the top, and the upper midrange is smooth and liquid. These tubes reproduce the human voice, especially female voices, with haunting realism. The 1970s Mullard made have an attractive sparkle at the top with the rich bass, and these tubes are usually priced less than the older types.

RCA, RAYTHEON, GE, SYLVANIA, and other USA made NOS: This group is very diverse. The older RCA, GE, and some other brands of 6922, 7308, and 6DJ8 were often made by Siemens, Mullard, or Amperex, and usually are a bargain. The USA made 1960s vintage 6922 and 7308 are nearly always made for the military, although there were some early industrial versions made by Westinghouse and other brands. They are fairly good and usually priced very low. Their sonics are reasonably well balanced. The 6DJ8 tubes made in the USA, and the 6922 or 7308 USA tubes made AFTER 1975 are generally best used in test equipment that calls for them, as they are not particularly attractive audio tubes. The earlier 1960s versions are somewhat better, including the greyglass GE. Their prices are usually very low, putting them on par with the Russian or Chinese types. You may want to try them if on a strict budget, for they will surely outlast several sets of current production tubes, and probably still sound better than the Russian-Chinese trash. Overall, the USA made tubes are a nice surprise with their low prices as compared to the European types.

A Note About Amperex 6922 and Bugle Boy Tubes:

Because the trade names of "Amperex" and "Bugle Boy" have been sold to a USA electronics firm, there is much confusion in the tube world about Bugle Boy tubes. I will try to clear up the confusion as briefly as possible. This company bought the rights to the name Amperex, the name Bugle Boy, and the rights to the cartoon tube logo. This new owner is NOT Dutch Philips or North American Philips, who originally owned Amperex and made the 1950s to 1970s vintage tubes that audiophiles want. When I mention "Amperex Holland" or "Amperex USA", I refer to the original Dutch and North Amperican Philips owned companies (now defunct) that made the vintage tubes, now in demand by audiophiles, up until the late 1970s. There are 6922 tubes being sold today under the name Amperex Bugle Boy, and they even come in a green and yellow box like the original Amperex tubes. THESE ARE NOT AMPEREX TUBES AT ALL, AND THEY ARE NOT NOS. They are either relabeled new Chinese or late production JAN Sylvania tubes. These fakes contain several errors:

1. Genuine NOS Amperex Holland or Amperex USA NEVER used the words "Bugle Boy" on their tubes or boxes.

2. Genuine NOS Amperex tubes NEVER had the cartoon Bugle Boy printed on the tube box.

3. Philips/Amperex Holland or North American Philips/Amperex USA NEVER made a 6922 (E88CC) tube with the Bugle Boy cartoon on the box. They also NEVER made a 7308 or E188CC with the Bugle Boy on the box OR glass. In this family of tubes, only the 6DJ8 had the cartoon tube on the glass, but again, never on the box.

4. Again, there IS NO SUCH THING as a genuine NOS Amperex "Bugle Boy" 6922 or 7308 tube. This bears repeating!

5. We stock the real NOS 1960s and 1970s Amperex (Holland and USA made) 6922 and 7308 tubes. They either used the white label or the orange (or later green) globe logo label, with either the PQ (premium quality) logo, or were military USN/CEP or JAN labeled. We also stock the real NOS Holland 6DJ8 Bugle Boy tubes from the 1960s. Amperex did not make these in the USA. These DO have the cartoon boy on the label, but NEVER had the words "Bugle Boy" printed on the box or the tube glass.

6. Nearly all of the NOS 1960s and 1970s real Amperex tubes have the factory date codes on the side of the glass. The fakes do not.

7. Some knowledgeable sources have reported seeing recently some Amperex HOLLAND made 6922, and even rarer, a few 7308 gold pin tubes with the Bugle Boy cartoon on the glass. They were only Holland made, none from the USA. It appears there were so few made in the early 1960s that it is unlikely any will turn up anywhere outside of The Netherlands or neighboring countries in Europe. Determining if they are real by the date code and other construction factors requires some skill. Since they are so scarce, it is advisable to treat any "Bugle Boy" 6922 or 7308 tube as a fake, unless you can clearly see the Holland date codes on the glass.

Here above is an example of fake Amperex Bugleboy 6922 tubes. There are several clues to the trickery being done here: The tube is an A-frame top getter. The A-frame getter support was used after the Bugle Boy logo was discontinued and the Amperex orange globe logo was being produced, for the type 6DJ8 tube. The 6DJ8 is electrically the same as a 6922 but the quality is inferior. The A-Frame getter was also NEVER used on a 6922 tube! The type font is thin and wrong for Amperex tubes. The Bugle Boy cartoon character is what is known as "the thin man" which was a thinner and more detailed picture, used only from about 1962-1964, but never on A-Frame getter tubes (which are 6DJ8 types, 1972-1976 vintage) and never on 6922 tubes. None of the tubes have the factory date codes near the bottom. This indicates a tube made after 1975. So what we probably have here is an Amperex made 6DJ8 A-Frame getter tube, likely made after 1975. These would have come with the orange or green globe logo on the glass, and standard pins. Someone has carefully removed the labels, put on the fake 6922 Bugle Boy labels, and then electroplated the pins with gold. This attempts to deceive the unwitting buyer, who thinks they are buying a real 6922, into spending 4-times the amount that the 6DJ8 tube is really worth! We at Brent Jessee Recording are trained to spot fakes, and all of our tubes are guaranteed genuine. Buy from a dealer you can trust!

It is very difficult to find tubes from a NOS Production Period such as the from the 60's Period, that are perfectly matched for the purpose of being used in a Phonostage.

I have Siemens and Mullard Brands which took months of searching and arranging a purchase condition where if a Tube did not measure to a certain level I was allowed to return it.

I got there in the end, one Tube came from Japan ands another from Germany to make a matched pair.

Tube dealers will supply tubes that will produce music and have a decent usage life.

To get Two Tubes with the Four Halves across the Two Tubes all measuring close and above manufacture Spec' is a challenge for certain era's of production.

This is where the real magic is to be found for a usage in a Phonostage, fortunately, these same owned Tubes are transferrable to a used DAC as well. 

OP,

Given the level of nuance we are talking about in Phono stages… I think you have to listen to an Audio Research to make up your own mind. To me they perfectly nail midrange bloom without being “warm” for the sake of warm. I can say that for me the ATC Reference 3SE is the best, musical, detailed phonostage I have ever heard.