Heerlen VR2 E188CC vs New York 7L6 6922:
OK, so I finally found the courage to swap the tubes to give a lil' more feedback.
The US 6922 immediately sounds a little more extended; highs are more shimmering, bass has a kick/punch while extremely tactile. Mids used to sound close to perfect to me before trying the E188CC and still sound great to me even afterwards, just different I guess; mids on both tubes has body, but it is lusher on the E188CC and "just" musical on the 6922. Listening to the 6922 again, I think the soundstage is much larger, and probably deeper than with the E188CC; actually that might account, in part, for the impression of vocals being a bit more "forward" on the Heerlen tube.
Now, as far as details and realism go, it's really difficult to pick a winner here... Details seem more emphasized on the 6922: they come at you in a bigger, meaner, way from the angles, where I could swear I could hear a little more mids and high mids details closer to the center of the picture with the E188CC.
So, yeah, I guess the E188CC is more polite than the 6922: lusher but tamer mids, less glorious highs, less punchy bass, but probably a better sense of low level detail than with the 6922. You really get used to the bass impact and shimmering highs of the 6922, but at the same time, you immediately miss this sense of center imaging with more micro-detail and less extremes that the E188CC. The 6922 is macro-detail with body and impact, and the E188CC is micro-detail with intimacy and focus. I'm obviously overemphasizing the differences here though, as the tubes sound more similar than not, but you can definitely tell those are different in a few ways.
It's terrifying how quickly you can get used to something better than before... Comparing both tubes, I could almost swear something is missing now lol; a sense of absolute realism and detail in a way. Guess I just need to order more tubes now... It never ends I tell you.
Oh yeah, measurements: I measured voltages with the 6922. Wall was 228V.
Heater - 5.89V
Plate (R) - 79.9V Grid (R) - 2.04V
Plate (L) - 79.8V Grid (L) - 2.05V
Where the last time I re-measured the E188CC (with 227V on the wall I think), I got:
Heater - 5.84V
Plate (R) - 75.2V Grid (R) - 2.06V
Plate (L) - 75.2V Grid (L) - 2.08V
So, no huge difference here. The 35 mA lower current requirements of the 6922 might be responsible for the slightly higher heater voltage. The other values are pretty similar.
Edit: The E188CC is back in, yeah that was quick I know... I guess an even better way to describe both tubes in only one word is: the 6922 is punchy, whereas the E188CC is liquid - that's the word I was missing earlier. And listening again, the E188CC's highs are actually very detailed too, whereas the 6922's highs can almost sound a little sibilant on a bad day. Definitely a bit more microdetail in the midrange of the E188CC, but less bass too, which is a bit of a compromise (it's hard to forget to way the 6922 renders a bass kick, it's almost like air is actually blown towards you ear).
Edited by Audiofanboy - 12/13/13 at 8:32am