I’ve been promising an in-depth review, but have been crazy with work and have not had the time, so I think I will do it in installments. First, I tried the WA5 with the stock tubes and have to say it sounds really, really good out of the box. So good, in fact, that I wondered if I wasted a lot of money on tube upgrades for little gain. I decided to do my initial listening through my speakers. I have Paradigm Millenia 300 speakers, which are very detailed are fairly neutral, have nice tight bass, but do not get into subwoofer territory, but can be a little on the bright side (they have titanium tweeters), so I have been careful in my system to balance this out (copper speaker cable instead of silver, etc.).
I had never heard a SET amp before, but had read a lot about that SET magic and had an idea of what to expect- smooth fluid mid-range, a lot of low level detail, huge and detailed soundstage, and weak in the bass. To my delight I found the WA5 had all of these traits except the one negative one. The bass was as good as my 125 Watt per channel SS amp without the subwoofer on. While the bass may not have plunged the into subwoofer territory, it was plenty low and punchy enough for me, with nice detail and a warm upper bass range.
At this point, I should probably discuss a little the type of music I listen to, what characteristics I look for when listening critically, and a little more about my system. I listen primarily to acoustic small group jazz and vocals, typically with large bands backing them up, and classic rock. Miles Davis, Sonny Rollins, John Coltrane, Ella Fitzgerald, Frank Sinatra, Tony Bennet, Julie London, Steely Dan, and Jimi Hendricks are often found on my turntable. I also listen to contemporary rock and classical, but not as often.
I value detail, soundstage, and warmth in my music. My source is a VPI Aries 3 with most of the upgrades, which makes it a pretty high end TT. VPIs are known for their ability to deliver a great deal of low level detail. My phono stage is a BAT VK-5P that incorporates 2 6SN7s and 8 6922 tubes. With the stock tubes it was a little bass heavy, but I tube rolled it to tame the bass and bring out a nice warm mid-range and more detailed highs.
With this setup, the WA5 (with stock tubes) presented nice tight warm bass, smooth mids, and detailed, if somewhat harsh and grainy highs (remember, my system tends to be a little on the bright side). It was a system I could live with, but I couldn’t wait to start the rolling to see what gains could be made.
I decided to roll the tubes one type at a time to check the differences one at a time. I started by rolling the rectifiers to Mullard NOS GZ34s. This change smoothed everything a little, particularly the highs, and brought out s little more mid-range. I then swapped the 6SN7s for Raytheon NOS VT-231s. These tubes are known for their silky, warm mids and detailed and warm, smooth highs. That’s exactly what they did in the WA5.
Now for the really good stuff- I had purchased some new production Western Electrics and some Sophia SET Princess Mesh Plates (the top-of-the-line with ceramic base and 1 year warranty), with the intention of comparing them to see which I preferred in my system.
First the Sophias: These 300bs really expanded the soundstage and added a lot of detail to the sound, as well as smoothed out everything. Bass was probably a little tighter, as well. Wow, this sounded amazing- when I closed my eyes, the band was right there in front of me. The soundstage was huge and went way beyond the width of my speakers. There was absolutely no hole in the middle, it was one continuous sound. I could pick out the exact placement of each instrument, and there was a great deal of depth, as well. If there was any flaw it was that, on occasion, the highs could get a tad harsh. When Sonny Rollins belted out some higher notes, there was an edge to them. I’m not sure, though, that this would not have been the case if it was live.
Now for the WEs: I immediately noticed there was much more body to the sound- a fullness that made the Sophias seemed a little thin in comparison. This was that magic WE mid-range that I had heard about! What a full gorgeous, liquidy midrange! For the first time, my system was not dominated by the highs, and there was not a trace of harshness or grain, but the low level details were still there. The soundstage may have gotten a tad smaller, but it was still extremely wide and deep. The bass was very tight and the upper base was warmer- acoustic basses sound fantastic! This was it- sonic nirvana!
Now, the Sophias are great tubes, and may sound great in some systems that already emphasize the mids and lack a strong, detailed high end, but they were not the best match for my system. I had a pair of Tung-Sol NOS 5U4G rectifiers that I thought I would try. I initially thought that these were an improvement as there was more detail and punch to the highs, but they proved to be a little harsh on some songs, so I went back to the Mullards.
Next I want to spend a little more time back with the Sophias- I really didn’t spend too much time with them, and I have tweaked the system a little more since then. I also need to do an in-depth review with the K1000s (this is, after all, a headphone forum!). More to come soon...