I put a lot of energy into trying to compare the sound out of the TT2 directly with the sound while the XI AUDIO Formula S is in between, and in the end I didn’t find out much about the difference. Still, it’s all good news in the end.
It was immediately clear that the Formula S sounded differently but it was very hard for me to understand what exactly the differences were. These ridiculous scenarios repeated a few times:
- In a specific track I find the music/bass/voice/soundstage/whatever through the Formula S amazing. So I switch (15+ seconds), and listen to the same part again directly from the TT2. And the damn thing sounds at least as amazing! In other words: the quality I found remarkable is independent from the amplification used.
- I find something ugly using one device. I switch, and the issue is there on the other device too. So it’s an issue either with the recording or the rest of the system (and not the amplification parts).
In other words: I had a hard time understanding what differences I should focus on when using the TT2 directly versus using the additional amp. Either the differences are too subtle to notice after the 15+ second breaks, or my listening is too untrained, or my hearing is crap.
I asked my family to help. Unfortunately each of them only tested a single Billie Eilish song, but here it is:
- My wife liked the sound via the Formula S better, even though she didn’t want me to buy yet another black box for a lot of money (and I didn’t even mention the Powerman). However, I have to take into account that I forgot to make sure that the volumes match for her listening.
- After careful listening our 14 year old could not decide: “Both of them are pretty good”, was the judgement. Fair enough.
- Our 17 year old found both great but slightly preferred the sound directly from the front SE of the TT2 as it had slightly “more clarity”. I was really happy to hear that as this statement fully aligned with my perception.
So I spent additional hours, tried really hard and went through a lot of music. To some tracks listened over ten times to be sure (e.g., Lumerian by Soen). And still I could not understand what exactly the differences were. The sound of Formula S (connected via inakustik premium audio RCA interconnect cables) sounded slightly differently but could not say how exactly due to my untrained ears and the 15+ second long switches. And the TT2 had a little bit more “clarity” or “transparency” which was expected. It wasn’t a critical difference though that would drastically change the enjoyment of the music for me. In other words: both are great.
The bass situation was really puzzling to me as I saw some people complaining about the lack of bass on Abyss directly from the TT2. I worked very hard to reproduce this issue. Listened to a lot of bass-heavy music, including a lot of metal but in the end I failed: to my hearing the front SE jack from the TT2 was producing just as much wonderful bass as the Formula S. This is completely against my expectations and I cannot explain it. I don’t think my hearing would be so bad that I couldn’t judge this but I cannot exclude this possibility. Or is there a significant difference in my setup? I wish I could invite those who missed the bass on Abyss from the TT2 to a joint audition and find out together what’s going on.
In the end it’s a win-win situation:
- I’m positive that the Hugo TT2 is powerful enough to drive the Abyss AB-1266 Phi TC headphones, even from the front SE jack. This result is against my expectations, and based on other’s reports I have worked really hard against it, but I have no other choice than trusting my experience. This is good news for me: I don’t have to add another component to my audio chain.
- On the other hand, the Formula S sounds like an excellent amp for the Abyss AB-1266 Phi TC headphones, even without the Powerman. It would be a strong purchase candidate for me if I had a DAVE which reportedly doesn’t have the power to drive the Abyss AB-1266 Phi TCs directly.
¯\_(ツ)_/¯
