There is another addition for the WA7 that can have an effect on the sound. They call it the WA7tp. It is a tube (12au7) based power supply that replaces the solid state PSU that comes with the unit. It retails for $649 or $399 when purchased together with WA7/WA7d and Woo Audio says that the WA7tp should provide “enhanced stereo separation, smoother treble, more air, more effortless sound”. I would say that is more or less accurate. With the Electro Harmonix 6C45, it made the sound more linear, but it still wasn’t quite straight enough for me. With the stock tubes, I liked the extra air and smoothness. It does offer a noticeable improvement. Is it worth 4 big ones? If you want to push the WA7 as far as it can go, than yes. But know, it offers an improvement, not a revelation. Of course, though, as with the amp, you can roll in some different tubes, and tweak the sound even more.
Now, it is time to discuss the differences in the two different WA7 units: the WA7, and WA7d. They both contain the same DAC and Amp unit, so the sound is the same. The difference is that the WA7, which retails for $999, has USB and RCA analog inputs. It has the ability to output an analogue signal and act as a standalone DAC, but that is a rather useless feature as, if you are going to spend $999 as a DAC, there is better you can do. The WA7d adds an optical (TOSKLINK) input into the mix, but drops the ability to output the decoded signal (not a big loss). The WA7d also adds $200, bringing the total cost to $1199. So, ask yourself if you need the optical input before you load in.
Now, on the “but” portion of tonight’s program. First, I have one small issue with the sound. It seems to be lacking a little rumble in the sub-basement. I was thinking I might be remembering the HD650 going deeper than it actually does, but upon plugging it in to the LF 336/Dacport LX combo, I could feel that bass in the bottom of my feet again. I really only noticed the lack of sub-bass with classical, as the punchy midbass is plenty fine for rock and the like, but I really like to feel the floor shake with Tchaikovsky. A pretty small thing, but worth noting. However…
I like big buts, and I cannot lie. My big but here comes where it almost always does, in the value for dollar area. Let’s say you are looking for a good, all-in-one solution, dac/amp for your computer, and that you are willing to drop $999 on such a solution. In this situation, I would go with the Concero HP from Resonessence Labs over the WA7. It is a little cheaper. It is smaller. It is USB powered. It maybe not look as awesome, but it has equally stellar build quality, and though the amp on the WA7 might offer better dynamics on harder to drive headphones (the Concero HP was very good with the HE500 and HD650, though), the DAC on the Concero HP is simply in another league than the (very fine) DAC on the WA7.
But, suppose you are interested in taking the WA7 as far as it would go. You want the optical input. You get the WA7tp. You roll the EH tubes. You are now talking about $1698. What’s more, with both the WA7 and the WA7tp together, you aren’t taking up much less space than a separate DAC and amp together. For $1698, you have some nice options for what DAC and amp combinations you could make. For the DAC, you could snag something like Concero HD, KingRex UD384, Violectric V800, etc. For amps, you could go with a SS from Burson or Violectric, or a tube amp from La Figaro, Bottlehead, or even one of Woo Audio’s amps. I am willing to bet that the Concero HD, matched with WA6 with its tube upgrades (which together should run about $1860) would sound a good step up from the WA7 combo, and won’t be taking up much more space, either.
This is just the way I see things, however. I actually feel a little guilty saying this as the WA7 is a VERY good sounding piece of gear. I just can’t get past the fact that, at the asking price, better sound can be had. You are paying a premium for the all-in-one factor, and, to get the absolute best out of it, you need to add a power supply that, in my eyes, negates that advantage of having a DAC/amp combo.
But, it is up to you, gentle reader. If you are reading this, and you think I am nuts, that my conclusions are asinine, and that my mother is a terrible person, then by all means, go for it. It does sound excellent.