Thoughts on the THX AAA 789, Topping A30, and Emotiva BasX A100 and a little note on the Schiit Loki.
It was a good Christmas at my house. I got the THX and a Schiit Loki. I'll talk about the Loki just a bit and then get into my impressions of the THX AAA 789.
The Loki: This is a super well executed little EQ. 4 bands. Ideally situated across the bandwidth for the best effect. It is essentially transparent and has a true bypass switch, or you can turn the unit off and the unit is bypassed altogether. When everything is set at 0 there is no noticeable coloration. Before the purists go off on a tear here's what I think and have always thought about EQ. EQ is absolutely awesome for compensating for a source, an amp, speakers, a room, or ears, or any combination of the above. I have some upper end hearing loss from years driving big trucks and just a little high end boost really helps. To that end the Loki is amazing. The high boost really makes the highs on the HD6xx's, 58x's, and HE400i's come out for me. Just a touch of bass is awesome on the 58x's and gives the HE400i's some of that planar punch that is a little lacking given all of their other good qualities. Anyway, if you ever fight with poor source material that's just a little too much or too little of something, I'd recommend the Loki, it's solid.
Okay, the THX:
Build quality: It's fine. It doesn't scream high end to me. My gain selector is slightly off of true. So when it's set to the 2nd gain position it's more at 11:45 than say 12 o'clock. But that's just the OCD in me. I'm sure if I wanted to I could probably open up the unit and adjust it so it lined up right. I only mention it because I read some mentions of this issue in the product discussions. Meh. It seems solid enough. Aesthetically speaking, in my opinion, it's a forgettable black box and that's just fine with me.
Setup: I'll compare to the Topping A30 and the Emotiva BasX A100 since those are the other 2 amps I use at my desk.
I used my HD6xx's since they seem to be the most common point of reference. USB input using Spotify on high quality and AIFF from iTunes library. I don't own any DSD files so everything will be from a CD quality or lesser frame of reference. Topping was on high voltage (still no idea what the low voltage setting does because it doesn't appear to affect the sound) and gain level 2. THX was on gain 2. Emotiva has no gain setting. Interconnects were Monster Cable THX shielded (back off man I got them on clearance with an employee discount from an old job selling electronics), or Amazon basics. Signal chain ran from the D30 to Loki, THX, A30, then finally the Emotiva. I volume matched and switched via the 1/4" inch during songs.
Single ended: This thing sounds great. It's interesting to compare with the Topping A30 with the Burson V5i mod. That amp with those opamps is pretty amazing and to hear it go toe to toe with the THX just reinforces that conclusion. Truly. The D30/A30 stack with the Burson opamps is amazing. The Emotiva is just what it is. It sounds great by comparison. If I were to rank them by sound quality I'd say THX, Emotive, then the Topping, but truly there's not a lot separating these 3.
Is the THX better? Without a doubt. They are all super quiet amps. You don't hear noise from any of them. They are all 3 very neutral in their presentation. The THX has just a little extra something. I can't put my finger on it. So I'll just leave it at that. Whatever it is it is enjoyable to listen to.
Balanced: I can't compare the THX with the other 2 balanced. What I can say is that with the HE400i's, HD6xx's, and HD58x's the sound is nothing short of spectacular. That little extra something is just magnified. It's not just louder. It's more everything. More dynamic. Fuller, wider soundstage. This is just a spectacular sounding amp. I wasn't sure if going with balanced would make that much of a difference but it is noticeable. What is also noticeable is that the HD6xx's and the 58x 's both scale wonderfully. There's something about the 58x's. I know there's a lot of debate over whether they are as good as the 660s's. I don't know if I'll ever pony up the cash for those but I will say that there is something pretty special about the 58x's for a $150 headphone.
Interestingly enough the only headphone that doesn't play nice with the THX are my Monoprice Monolith M560's. They sound okay through all of these amps but the only amp they sound great with is the headphone out of my Parasound Zamp. They don't sound bad, they just interplay oddly with the amps when things get busy musically and get really punchy in the mids and highs. Not sure what that's about. But I keep them around because they're built so beautifully. I wish all headphones had that kind of solid build.
So where does that leave things? The THX is everything people say it is and may just represent the last amp I buy in a while. I suspect that it is capable of giving more but I have bumped up against the limitations of my $100 DAC, compounded by the limitations of my source material being CD quality or lesser. That said, the D30 and the THX AAA 789 are a pretty amazing sounding pairing. I'm ashamed of nothing. I may look into getting DSD running on my library just to check that theory but at the moment I'm too busy enjoying the music.
I don't know if the THX is a "bargain" but it's certainly worth what I paid. There are people whose opinions I trust that have spent thousands on amps who say this holds its own against them. I'll take their word for it and save my cash.
For anyone not wanting to invest even this amount of money into this hobby I'd say get the Topping D30/A30 stack (provided you don't have low impedance headphones or some ridiculously hard to drive headphones). Stick in the Burson V5i opamps and be done with it. It holds its own against the THX for single ended very well. Then just buy headphones. They're the more fun part of this hobby in my opinion anyway.