Blazebirth Hall is widely recognized as one of the greatest black metal circles in Slavic nations, standing alongside the Temple of Full Moon from Poland and the Stellar Winter collective from the Moscow area, and the Ukrainian groups including Nokturnal Mortum and Ygg and holding its own. What's significant about Blazebirth Hall is that it's really centered around one man, Kaldrad Branislav, whose compositional skills show varied talents, determination, and his love for his nation.
Kveldulv is not a long album, clocking in just under forty five minutes in length. The first three tracks are standard, lo-fi black metal with harsh vocals, brutal riffs, and rapid-fire drumming that involves heavy cymbal use. Overall, I'd say Kveldulv is the epitome of Branikald in terms of style and how the album is set up; with three more standard NS style black metal tracks and a fifteen minute long ambient outro. I'm reminded of the famous second wave BM band Burzum's masterpiece, Hvis Lysset Tar Oss, as Kveldulv is quite similar in how it's set up.
Guitar work in Kveldulv is dissonant and heavy distorted, and the heavy use of tremolo picking and simplistic riffs make the notes clash with one another, the drumkit, and the bass guitar. It does a lot to create a wall of instrumental noise which serves as the base for the high point of Kveldulv, which is Kaldrad's stellar vocals. Other BBH albums involve more clean singing, but most of the vocal work in Kveldulv is harsh in nature. Kaldrad's angry rasps are difficult to compare to other things in black metal, as they're not the banshee-like shrieks Gorgoroth vocalists are known for, nor are they the death growls that Behemoth makes heavy use of. Rather, I'd compare Kaldrad's harsh singing to Varg's, and it does a truly phenomenal job of transporting the listener to the frozen Russian landscapes and villages of yesteryear, when the proud pagan warriors still walked the earth.
This isn't exactly Norwegian-style black metal; rather, I think of Kveldulv as ambient due to the minimalistic, repetitive nature of the riffs and melodies. As the focus is so heavily on the vocals, instrument work simply serves to fill in the gaps and underline its role as the backbone of the album. The three introductory tracks are tied together in a wonderful way by Kosmhall, a somewhat longer ambient piece which eschews the use of vocals and drums for strict tremolo guitar work. It's a fast-paced, curious track that seems somewhat like what Drudkh would have made if it was centered in a nationalist-socialist Russian tundra.
Overall, Kveldulv is a very well put together album and is a must-have for any serious follower of Blazebirth Hall or Slavic NS black metal.