Pros: Tube rolling is fun, powerful, good sound stage, low price
Cons: Hiss with sensitive phones, heat output, DIY chassis
I got the Project Sunrise ii amp specifically to drive my Hifiman HE-500s. I was interested in buying the kit, but doing a trade-off with the cost involved in getting a proper soldering iron I decided to buy the pre-assembled kit in stead. I have to give kudos to Garage 1217 (Jeremy) as the amp was excellently packaged. They take great care to make sure your amplifier arrives in perfect condition. The amp build quality and soldering work is superbly done.
I was immediately impressed with the power this amplifier put out with the HE-500s. In the past I have used a Lehmann Black Cube Linear and my Audiolab M-DAC headphone output to drive the HE-500s and whilst it didn't sound particularly underpowered I could immediately notice the difference with the PSii having more headroom and volume to drive the HE-500s to their full potential. The sound is definitely fuller and more authoritative. Putting the volume knob at 10 o'clock is enough to reach loud levels. The Lehmann BCL had to be set to at least 12 o'clock to get decent output and the Audiolab M-DAC to the top half/quarter of its headphone output range. Both solid state amplifiers sounded quite bright and the PSii definitely sounds smoother from top to bottom on the frequency range. The amp has good PRAT with the HE-500 and excellent sound staging, though a lot of this depends on the tube used.
I have also done some tube rolling which has been a lot of fun on the PSii as it makes it a breeze to swap out tubes. The stock tube is definitely not bad, but there is definite added mileage to be had with some quality tubes. The biasing process is a bit of pain, though the tweaking is in a convenient location, and I think the auto-biasing feature in the Project Ember amplifier will be very handy. I have since stuck with a 12V ECC801 Zaerix valve which I am enjoying a lot. It is definitely evident that the money saved on the chassis went into producing the best sound quality for the price.
Only real negatives that I can think of is that I cannot use my Westone 4 IEMs with this amp as it hisses quite loudly even with the volume set way down. I have detected no hiss with the HE-500. The other negative is that the amp gets very hot even with the open chassis. With the power button and cables at the back you have to be careful not to touch the heatsinks. The amp also picks up interference at times from my cellphone which can also be a nuisance.
I'm definitely keeping this amplifier with the HE-500, though I am tempted to get the Project Ember amplifier as well to see what it is capable of. As a bonus the RCA outputs on the PSii also works really well with the B&W MM-1 desktop speakers I have. I'm getting surprisingly good sound out of these little speakers using the line-in.
For the price this is a great headphone amplifier and well worth trying out!
Apple Macbook Air 13" 2012
B&W MM-1 desktop speakers