I have been using the Prelude for some time since purchasing it from Bloom. Needless to say, I have no major complaints about this headphone amp. It is simply built like a tank and sounds beautiful. The best way to describe the sound signature to me is dynamic, musical, and organic sounding while still providing amazing detail.
I personally run a Eleven Audio K-Dac into the Hifiman Prelude and then into the Orchard Audio Valencia. A little overkill with the power but everything pairs very well together. I was using it with the SMSL VMV D2R dac prior to purchasing the K-Dac and literally loved how good this combination made vocals. I actually had hard time letting he SMSL VMV D2R go because it paired so well with the Prelude.
With all of this being said, this amp tends to sound better when you are running the dac at a lower voltage aka rca. If you are using xlr, I would recommend running the Prelude on low gain and high gain if you are using rca.
I wanted something fully class A, before getting this I auditioned the Dx-9 Topping all in one and while good it still suffers from the inability to maintain notes after the initial hit, the mids also came up to much. The Prelude on the other hand can maintain notes appropriately with ease especially when paired with a dac that has good bass slam and 5v to the xlr outputs. This amp will be with me for quite sometime as I use it for movies-game’s-and music, it does all that i ask adequately. This will be paired with Mh tungsten in the future as my reference point. If you have the means don’t hesitate to try this product.
I purchased this specifically to drive my Hifiman Susvaras. It is a beast when it comes to power. Even on low gain, it drives the Susvara's effortlessly. The big surprise was its abilities as a preamp. I tend toward analytical sound and equipment that produces it and I found this to be a good non-tube option for bringing in some warmth. I also used this to drive the RAAL interface box for RAAL Requisite SR1a and it works beautifully. At $2.5k it is a true bargain for me. It's winter so the heat generated is not an issue but if heat generation is an issue then look elsewhere.