I finally have the time to sit down and write up my tube rolling adventures. But before I start, I’ll give a little history. My LIO replaced a Joule Electra LA100 and Wellborne Moondog (2A3 SET) combination. This drives a pair of VMPS RM30s with the powered bass option. My source is a TTWeights GEM with VTA pod and modified Jelco 12” arm, Van Den Hul Colibri, Choir Audio / Hashimoto SUT (HM-3), into the LIO MM phono stage (tried the internal xformers, the Hashimoto is a better match to the Colibri.) I also have a Herron PHMC-1 that will eventually go up against the internal phone stage. The LOI uses (used, more later) the AVT tube stage and SS amp. I do very little digital at home – mostly around the holidays for background listening.
To keep thinks repeatable, I used the following albums for testing:
Oregon – In Performance (Elektra original pressing)
Miles – Sketches of Spain ( Classic Records 200g)
Weather Report – Heavy Weather (ORG re-release 45RPM)
Clannad – Fauim (Topic original pressing)
Fleetwood Mack – Rumours (Japanese pressing)
My first impression was that while very, very good, the LIO lacked the tonal refinement and overall palpable presence of the all tube / SET system. Yes, it could play louder, and possibly deeper, but overall 3 dimensionality and just plain “humanity” was missing. The soundstage was also slightly constricted. So I decided to try some tuber rolling.
First up was a pair of Telefunken 7dj8s: Transients were faster and brighter. In Drum Solo (Oregon), you could almost sense Wolcott’s fingers on the drum heads and the differences in impacts on each drum. Towner’s 12 string on Icarus was rich and bright. But Moore’s bass was a little thin, and McCandless’ woodwinds (mostly oboe) wasn’t as rich as I was used to. This turned out to be a fundamental problem with these tubes – they opened up the high end, but leaned out the rest in the process. Not my cuppa.
Up next were Mullard CV2942s. Okay, this is better. Tones are richer and more developed. Soundstage gained some more dimension and I have some palpability. I used this configuration for a few months, and while it still wasn’t as good as my SET system, it was so close.
Enter the DHT
The installation of the DHT modules went quickly and without incidence. I fired the unit back up and let it sit overnight. Okay, now we’re getting somewhere. The soundstage expanded, tonality was almost where I wanted it, and images gained palpability. As others have written, once you hear the DHT stage, you can’t go back. Going back to the Oregon album, side two opens with George Schutz walking to a mike and introducing the band. This part was recorded in Carnegie Hall, and you can hear the hall ambience as he speaks. Drum Solo sounds more spread out than before, the hits are just as defined, but everything is more integrated into the whole. Rumours takes on a more tense feeling – there really is a lot of bitterness on this album, and much of it gets glossed over on many systems. You can also hear the mic colorations on Sketches. When the horn chorus comes in on Concerto it is too bright and brash. I’m thinking this could be the new 2A3, the brightness may diminish as the system burns in.
A little after a week of listening I received the DHT tube package. So I spent the next week going through these tubes. This is what I heard:
EML Mesh Plate – These had the best sound stage and cleanest, most refined highs of all of the tubes. Tonality was as good, McCandless’ oboe was rich and nutty, and Towners 12 string gained a body. Schutz’s voice resounded through the hall. Birdland (Heavy Weather) gained depth and sonority, while the horn chorus on Concerto lost the brashness. Now you could really hear the tension on The Chain (Rumours.)
300B – I was predisposed to not like this tube – most of the 300Bs I’ve heard sounded restricted compared to 2A3s. This was even the case with a WAVAC amp that I heard. I’m going to chalk that up to the tube’s use in an output stage. As a driver, the tube is a completely different animal. No, it’s not as extended as the EML, but it did the 3-D psychedelic stuff that Rosenberg used to write about. This was palpability in spades, and it was good! I wish I could have spent more time with this tube.
SV-811-10 – Umm, I need to spend more time with this tube (I have a pair downstairs). There was nothing wrong with the sound, but nothing stood out either. That’s either good or bad depending upon your POV. I didn’t hear any additional color; the 300B might be the king with that. The filament glow is kinda funky. I wish I had more to say.
CX-301A – The trick with this tube (and maybe the 811 too) is that is has a different gain structure. You need to pull the volume up a few dB to match the 2A3 and 300B. Once that is done, this is a good tube, but again, nothing stood out. Again, maybe more time is needed.
Shugang Treasury 2A3 – These were the last tubes in my Moondog; they’re probably around 4 years old. I thought I’d add them to the survey since I have them and will be using them. First off, they are not as good as the EMLs, not quite as extended, and not quite as quiet. But damned close. They also sound similar to the 300Bs in that 3-D psychedelic way. This made me do some checking, because the EMLs don’t pop out images in quite the same way. Examining the Treasury, the 300B and the “stock” EH tubes, I’m seeing a lot of similarities. The filaments look identical, as do the top and bottom spacers. Even the plates have the same basic shape (the 300B plates are slightly larger). I’m thinking that these are not “true” 2A3s, but are instead 300Bs with a lower filament voltage. That would explain the similarities in sound.
The Shuggies are now my standard tube; they are better than the EHs, and my wife will kill me if I attempt to drop over 600 on a new set of tubes right now.
Vinnie and George, thanks for setting up the tour. Now I just have to play with the phone stage…..