Casual music listening is a fine way to spend a Sunday afternoon or an evening with friends, but every once and awhile it is equally entertaining to get down with full double blind A/B test – just to help cleanse the palate. Such was the calling for yet another casual get together at Schiit Audio’s retail location in downtown Newhall. The kind folks at the SchittR took many steps of preparation to deliver an evaluation experience that was truly “blind” – neither the group listening nor the person switching the samples knew the cost or even the model of any of the items under scrutiny.
The category for the evening’s festivities this Thursday was tubes. While other meets focused on comparisons for turntable cartridges and preamps, the portability of small analog tubes allow for full concealment of any branding. The subjects arrived fully wrapped in a plastic covering, with even the bottom connections rebased to a generic option that was consistent from unit to unit. Four Schiit Saga + were enlisted for use with a splitter, switching box and cabling from Cablesforless.com. The Saga + was chosen for use with a single tube, as opposed to the more expensive Freya + which utilizes two pieces of glass in amplification. Strictly speaking the test is actually a double blind A/B/C/D execution for each round, as eight tubes were sent over for comparison. In order to crown some winners, two sessions of four tube comparisons were conducted with the two victors from each round duking it out in a final 4 shootout.
The actual reveal list of tube models arrived in a sealed envelope (thanks to Cablesforless) and wasn’t opened until after the last decision had been made. Thanks to a handy switch box, music could be played in varying order and duration throughout the critical listening sessions. A Schiit Yggdrasil DAC (fed by a Macbook Air + Qobuz) and Aegier power amplifier rounded out the front end for the Salk Song 3 ($2.9k) loudspeakers. The cables connecting every device were all the same price and model. The NOS tubes evaluated were the RCA 6SN7GT Grey Glass 1942 (~$150), Tung Sol Mouse Ears (~$35), Sylvania 7N7 Tall Body, AKA Frankie 1930 (~$25), Foton 1954 6H8C Ribbed Plate (~$20), Sylvania Bad Boy, VT 231 War Issue (~$50), CBS/Hytron 5692 (~$100), Melz 1578 1984 Vintage (~$30), and Ken-Rad Black Glass VT 231 War Issue (~$100).
Listening started with Wilco’s Jesus and moved to Bach’s Chaconne classical track, ending with Riders On The Storm by the Doors for the first grouping. Observations as they came in on the fly were as follows:
1 – RCA 6SN7GT Grey Glass 1942
The RCA Grey Glass managed to pull out some decent mid-range without sounding overtly hollow or resonant. On some tracks the response felt a little backed off in the treble end of things, but didn’t appear to be as noticeable in this regard on others. Sound staging was decent and left the listener with the illusion of a wider field of play.
2 – Tung Sol Mouse Ears
The “Mouse Ears” tube initially fell back in the mids a little, but still retained some relationship to the other contender’s frequency response on this list. The overall image suffered from some smudging as we made our way through the setlist, with some attendees describing the sound as the “messiest”.
3 – Sylvania 7N7 Tall Body, AKA Frankie 1930
When the 7N7 Sylvania came up to bat, the linearity of the response was more readily visible during playback. There was perhaps a touch more grain on some tracks, but gains were felt frequently on whatever sonic task was put forth. Tonal information hit new highs, but some narrowing of the sonic field was felt by some compared to the best performers.
4 – Foton 1954 6H8C Ribbed Plate
The Foton 6H8C sample we received did not stand out as well as the others in its group. Notable loss of dimensionality and fidelity was felt to the point where comparisons were drawn to “mushy AM radio”. However, this impact was felt less or more depending on the track, showing increased levels of variability as time wore on.
Of the first grouping, preferences started heavily with the Sylvania 7N7 Tall Body, pulling up a total of four “best sound” votes. The RCA 6SN7GT Grey Glass came in second with three votes, moving both competitors to the next round.
The second series of tests started with Riders On The Storm on again, but quickly evolved to audiophile standards Hotel California (acoustic) by the Eagles and Norah Jones Don’t Know Why for more reference points to pull from for the group.
5 – Sylvania Bad Boy, VT 231 War Issue
The first tube out of the gate came prepared with premium high frequency resolution and dense texture information. After the first rotation it appeared that Sylvania Bad Boy might be the clear winner, but more back and forth against the Ken-Rad Black Glass revealed a slight advantage to the K-R.
6 – CBS/Hytron 5692
While many of the tube comparisons gleaned only small changes in either tonal structure, frequency response or overall believability, both the CBS/Hytron 5692 and the Melz 1578 offered up presentations that were noticeably degraded. In the case of the CBS, the results manifested in an overtly shouty, or boxy-like crunch in and about the midband.
7 – Melz 1578 1984 Vintage
Similar to the CBS/Hytron, the Melz 1578 delivered a slightly diminished performance compared to other options in the shootout. For the Melz, the energy conveyed simply didn’t pop with the rest of the class. Upon reaching this stop, several listeners felt compelled to say the retrieval sounded simply “dead”.
8 – Ken-Rad Black Glass VT 231 War Issue
In comparison to the Melz the Ken-Rad Black Glass put out very lived-in, energetic response. In fact, more direct comparisons to the rest of the 4-unit grouping had to be made to confirm the tight focus and full-bodied presentation. The Ked-Rad made it easy to get a sense why #8 had such a broad appeal within the listening group.
The voting response for attendees for the second round of tubes was unanimously positive for the Ken-Rad Black Glass. However, from my listening vantage point, there was an equal enthusiasm for the Sylvania Bad Boy. Both tubes moved on to our final round which was randomly relabeled as “A/B/C/D” for comparisons.
My listening notes only reflect an additive single statement for each tube in the final 4. For the Sylvania 7N7 Tall Body it was “Less body.” For the Ken-Rad Black Glass it was “More upper room, more natural”, the Sylvania Bad Boy “Reduced resolution, less body”, the RCA 6SN7GT Grey Glass simply “More breath”. The last comparison made, a final tally was taken and the results envelope was opened. Emerging victorious from the fray was the RCA Grey Glass as the preference for most. A close second was the Ken-Rad Black Glass War Issue. Interestingly, the included preference ranking of the organizer from CablesForLess.com started with the Ken-Rad and only had the RCA at #4.
While some of my role as a reviewer is one that is constantly looking for minute differences in sound, occasionally it will take a bit of insight and self-restraint to identify when things sound consispondingy similar. This was the case for many of the tube comparisons here. With the exception of the degradation notes above, most of the average performers and above average were vastly similar in execution. Weather the poor output for the few were a result of jostling in transit, subpar connections or something else, we will never know. It is important to note that most of these tubes are very old, and everything physical eventually suffers from the inevitable, endless march of time. Just because one of these tubes didn’t excel in this situation, doesn’t mean that all units in the field will perform the same in any given situation. So while there were some noticeable gains in collective performance from a few candidates, the overall race was so close that only significant deficits in quality stuck out against the negligable. As the SchiitR meetups continue to evolve, the range of products tested has shown some interesting insights as to the overall impact of the category to the fairly consistent playback setups. In order of ranking, it appears in this series that preamps have made the most impact on sound followed by tubes and then turntable cartridges – generally speaking.
As a final note. In a just-for-fun execution, we also compared Schiit’s current Tugsol tube that ships standard with the Saga + and the comparative performance to our top two winners was extremely admirable, if not downright competitive. It was a nice final wrap-up listen to bring the experience back full circle. Special thanks again for Schiit Audio for hosting and Cablesforless.com for supplying all the necessary components to execute this meeting in a true double-blind fashion.