Emotiva RPA-1 Listening Tests

Finally, we get to the most controversial of sections in an amp review. On another website, users would skip to this section and digest hungrily every chocolaty midrange and authoritative bass comment. But this is Audioholics, folks, amps sound the same. Right? Well, not exactly. All things being equal, I'd agree with that statement, but this amp's duty is to push harder to drive speakers. When you hook up a low impedance/low sensitivity speaker to a midlevel receiver or a mediocre amplifier, you're going to risk clipping which could damage your speakers and/or create drastic frequency response variations both of which don’t lend to quality audio reproduction. Not to mention that many of these "hard to drive" speakers just plain require more power than your typical receiver can provided. With speakers like these, you need to have a dedicated amplifier with plenty of power and tons of headroom. When I was first utilizing the RPA-1 for the RBH TK-5CT review (forthcoming) I immediately noticed a difference between the RPA-1 and the amps in the Denon 2307CI (which was in for review around the same time). Taking into account the considerably greater power of the RPA-1, this isn't surprising. The Emotiva amp is obviously going to stay stable at higher volumes with harder loads than any the mid-level receiver.

CD: Bang & Olufsen Vol. XIII – The Sound of Perfection
What is quickly becoming one of my standards for review, the B&O test disc was the first one I turned to when listening to this amp. While I can only really stomach the first five or so songs (seriously, who thought a cover of "Come Together" by a scat/techno band was a good idea?) it universally has good fidelity. The first thing I noticed during the listening test was how every note seemed tighter. Of course the RPA-1 played louder (I could rarely get the little needles past the 1/3rd point on the dial) and cleaner, but even at moderate volumes I perceived a tightening of the overall presentation of the music. Part of me thinks that the soundstage expanded though it is really hard to be sure of this without a more controlled A/B test. As I am generally doing these tests alone (the wife hates loud music - even if it is music she likes) everything was sighted with more than the preferable time between comparisons.

Still, you don't need to do a blind test to know the differences between a horse and a cow. The Emotiva Audio RPA-1 kept pushing the TK-5CT's and the Usher Audio s-520's to their limits rather than holding them back as the Denon did. I suppose "holding them back" is too harsh a term. The Denon faired well with these harder to drive speakers, much better than I would have thought. I was impressed overall with how loud and clean the Denon played but it really wasn't much of a contest with a dedicated two-channel amp that weighs more than almost two of these receivers put together!

DVD-A: Lowen & Navarro - Carry On Together
Yes, yes I know this is a DVD-A but I couldn't get the CD side to play in the Denon DVD-3910. I know from experience that the vast majority of the information is in the left and right channels so I wasn't all that worried about it. Each instrument was lifelike but I was especially impressed with the kick drum which just sounded tight and deep with all the proper harmonics that you associate with one of the more difficult sounds for speakers to produce. The vocals were well separated and distinct, each placed securely in the soundstage. Again I felt the soundstage was a bit larger than I was used to. Sound separation - between the different notes, instruments, and vocals - was excellent with a nice depth to the music.

Good music (and by good I mean well recorded and mixed) has a depth to it. If you desire, rather than listening to the main vocals and instruments, you can focus on something less prominent. These background instruments are usually the first to be affected by a compression codec so you'll want to listen to see if they sound realistic. What is especially telling is when an instrument is suddenly overshadowed by another like a piano vamping after a solo as a guitar comes to the forefront. If that instrument suddenly loses all the harmonics, depth, and presence when it recedes into the background you know that you've been the victim of compression. The RPA-1 ensured that each instrument was presented as it was mixed. It can't bring a compressed instrument back to life but it can make sure that each sound has more than enough power to be presented true to the recording and mix.

CD: Yello - the eye
You can't read an amp review and not hear about bass. It just seems to be the first thing that trips off a reviewer's tongue. But why? Can amps really "tighten" up bass that much? Well, the thing to remember is that a bass note requires a lot more power than other frequencies so it is possible that a lower powered amp or the internal amps on a receiver are clipping those notes ever so slightly while having plenty of power for everything else. So, while it might seem like an amp or a receiver is doing a great job overall, it may be that it is having a hard time with bass without you knowing it.

Since I did most of this review with the full-range RBH TK-5CT towers, I was pushing the RPA-1 with a full range sound (not crossed over into a subwoofer). Part of my earlier assertion that their was an overall "tightening" of the sound I believe was mostly do to the increased power available for bass notes. The eye is a fairly bass (and treble for that matter) heavy techno CD. It is murder on bad speakers and none to kind on amps. The RPA-1 generally presented cleaner bass notes with reduced hang-over and an overall tighter presentation even at very loud volumes. Was this a night and day difference? No. But neither the RBH TK-5CT's nor the Usher Audio s-520's present extremely hard loads. Difficult loads, sure, and maybe a bit more than you should force on your average receiver. With a harder to drive set of speakers, these differences are only going to become more apparent.