Pros: Powerful, yet balanced and detailed sound.
Cons: Stacking the units caused a feedback sound to my headphones.
Apex High-Fi Audio Peak and Volcano
You can read about the specs from the description and the other reviews.
There is a reason this set-up is listed as the most popular headphone amp - the audio quality and design and nothing short of amazing.
I am a noob in the headfi community. I have been a member for just over a year now and have been able to make it to the mid-tier of headphones and headphone amps. The HD800, LCD3, HE600 are still out of reach for my budget. For this review I used the Hifiman HE4, Hifiman HE5LE, and the Denon 5000 to listen to my music. My sources were my mac mini, iPhone, and Hifiman 601 player all using Flac or lossless music. I listened to classical, classic rock, rap, r&b, and hip-hop.
The Apex High-Fi Audio Peak and Volcano was loaned to me by Todd, the CEO of Apex. He was kind enough to let me demo his unit and because I loved it so much it is going to be my next big purchase.
I have been using all of my headphones for the past few months with a Hifiman EF2A entry level tube amp and a Nuforce ICON HDP amp/dac. Because I am so new to this hobby, this setup kept me more than happy, in fact I was in love with the combination of headphones I have as well as both amps. I was up late one night and saw there was a demo program for Todd's amp/power supply combo. Just like most of you, my curiosity got the best of me and I asked to take part in the program. Todd responded to me the next day and within 2 more days the unit was shipped to me to San Diego all the way from Michigan. This demo program costs a lot of money just to ship the unit. So, thank you Todd for your generosity. But by no means, is this review a reflection of his kindness. It wouldn't be fair to anyone if I wrote this review under the influence of his kindness. I read all of your reviews and trust that your reviews are your own thoughts because that's most likely where I will be spending my money next. Sorry for the long winded explanation, but now onto the review.
The first thing I noticed when I unboxed the demo unit was the build quality. Just by the looks and feel, I have no doubt that this setup would last years and years before anything failed. I would have no issues buying this unit used on headfi because I know that any unit used responsibly will last me forever. Unfortuneatly I never see these used, probably because the owners don't want to part ways with this set-up.
Second, it literally took me 2 minutes to set the unit up. One power cord from the power supply to the amp, insert the tube and plug in the power cord into the wall. I then hooked up my mac mini to listen to Apple lossless music with all three of my headphones for a hour a night for 4-5 nights for each set-up. The most impressive trait of the unit is the clean and clear sound of the music. Nothing is over expressed - the power had a balanced natural sound that enhanced and got the most out of all three of my headphones. The biggest surprise to me was with the Denon 5000. Before I demoed the Apex set up, I never really enjoyed my Denon's. I thought the bass was too muddled and the sound was too unbalanced for me. But I do prefer Hifiman headphones because I prefer the sound of the orthodynamics- they are more balanced and clearer in my opinion(I know all of this is subjective though). The 5000's were my first headphones to demo and it was instantly clear how clean the power output is. The denon's became enjoyable to listen to. The bass became so much clearer and less muddled that I actually enjoyed listening to them for the first time ever. I was on the verge of listing them on headfi to sell, but I realized that my problem was the amp. It was that or commit more money and send them away to get modded...Now I can keep them as they are and when I want that closed sound I just need to buy my own Apex setup.
I then used my hifiman headphones with the hifiman 601 and I was amazed. I no longer have the desire to buy the HD800's or the LCD3's...I am in love with this setup. I haven't purchased a single new headphone after demoing the APEX unit. I realized that the APEX brought out the best of my hifiman 601 and the headphones. A lot of people complain about the high sound that comes out of the Hifiman ortho's and it is true with the Nuforce HDP. The high treble sound puts too much pressure on my ears and my ears get fatigued quickly. With the Apex Peak I listened to the headphones for hours. My wife actually came and got me out of the office to go to bed. I was listening to my music until 3am...I had listened to all the genres of music I have for 4 hours straight. It was one of those moments where I completely tuned into my music and nothing else existed. That was it for me...I knew I had reached and end to desire more expensive gear.
I know this review isn't technical - I apologize I don't know as much as all of you in that sense. I do know what sounds good though and this is it.
There is a reason this AMP is number one on the headfi list and it is because the sound is amazingly awesome. For me, this will be my next purchase. If anyone has one they want to sell to me, send me a PM. If I missed something in this review that you would like to know, please send me a PM.