Issue No. 1 1998
by Francisco Duran
When I first listened to the Alternate Audio CA35 amplifier in my system, I thought to myself, what's the big deal? The tonal balance, bass and soundstaging capabilities were OK. It had a warm, sweet sound, but not much ambience. Then a call from fellow audioMusings reviewer Sherman Hong informed me that I had to reverse the plarity at either the amplifier or speakers. After doing so, the sound really snapped into place. But before we get too far into the sound of this amplifier, let's check out some of its features.
The CA35 is a stereo, high-bias, class A power amplifier which puts out 25 single-ended watts per channel. There are only two MOSFET transistors in the signal path. A standby circuit keeps the amp warm without excessive power consumption. There is full monitoring of DC offset and temperature conditions, indicated by LEDs on the front panel. By the way, the CA35 does run very hot!
The CA35 is your basic black, low-profile, rectangular amplifier with heatsinks on the sides. The most striking features of the amplifier's back side are the beautiful five-way binding posts made by TIF. The inputs are standard unbalanced RCAs. Also on the back is the main power switch, alongside the left and right channel fuses and the IEC connector for the power cord.
I threw an eclectic set of discs at the little guy, and for the most part it came through in good shape. With the amplifier in my system, I no longer cringed at cymbal crashes, snare drums, or dynamic peaks of any kind. The Eagle's Hell Freezes Over was gorgeous. The music sounded smooth, with an overall golden sheen. Even the clapping of the audience sounded natural. The depth of the hall was also very apparent.
Then I put on a disc which is not bright, sharp or steely in sound, but the music sure is-Metallica's And Justice For All. I came across this baby through my guitar slingin' nephew, because I told him I liked the song, "One." This song is a musical version of a film called Johnny Got His Gun, which deals with a guy who comes back from the war with no appendages and deaf, dumb, and blind. He communicated by using his head to tap out Morse Code messages. Very powerful, and transferred well to music by Metallica. For the most part, this disc is straight-ahead, gut wrenching, loud, hard rock. I feel this disc should be run through a stereo system now and then instead of the usual wimpy audiophile test disc, and played real loud, just to see if your speakers can still hang. Mine sure did.
How did it sound? The guitars rang out as clear and sweet as I've ever heard electric guitars through my system. Guitars, drums, and James Hatfield's gravelly vocals all came together very coherently. Metallica? Sweet? Coherent? Am I losing it? OK, let's turn the Mortal Kombat disc, same deal-tight, clean, and slightly warm. If anything, I had a problem with dynamics on these discs, but more on that later.
So I thought, what the heck, let's switch gears, and put on the Anonymous 4 Yools Night Disc. As the Dice Man would put it, "You know, the CDE of four chicks in a church singing their hearts out." I wasn't really in the mood for this kind of music, but I wanted to throw everything at the little CA35. Once again, the vocals were very natural sounding, and sibilance was very well controlled. I did notice that when all four women hit the louder passages, a slight excess of energy came through, but since I hear this on my Classe amplifier as well, it must be in the recording. It also seemed that I had to turn up the volume quite high on this disc to get a better sense of the recording space, but I still think this is due to the way the CD is recorded. However, after a few moments of listening I pretty much forgot about being critical, and just enjoyed the singing. Music to soothe the savage beast.
One thing leads to another, so on went Corelli-Conceti Grossi Opus 6, with Nicholas McGegan conducting the Philharmonic Baroque Orchestra on Harmonia Mundi France. The music just seemed to blossom from the instruments. This to me is the strong point of the CA35. String sounds of all kinds, whether strummed, plucked, or struck with a bow, from the lower midrange to the lower treble, sound ever so sweet and coherent. Vocals sound real, and there is a layering and depth to the soundstage that is uncanny.
But alas, in life there always seems to be something out there to spoil the party, and in this case it was dynamics. I first noticed this on the Eagles disc. The guitars opening track six, "Hotel California," sounded great, but as soon as the bass and drums kicked in, things seemed to wimp out. It sounded like Don Henley was holding back every time he hit the drums because he didn't want to disturb anyone. There didn't seem to be as much impact on the drums as I'm used to hearing through the Classe. Also, the bass guitar had plenty of body, but not as much impact or snap. The pace and rhythm sounded slightly lazy and lackluster, as if the Eagles were tired. The same was true of the Mortal Kombat soundtrack. The bass reached down pretty far, but it didn't have that gut-wrenching, chest-hitting slam. The pace seemed a bit slow and lacking in immediacy and life with the Corelli disc, also.
If it sounds like I'm picking on the little CA35, perhaps a comparison with my Classe CA2000 amplifier is in order. Both amplifiers are in the same price bracket. With the Classe amplifier back in the system, the Eagles' disc sounded faster and slightly leaner. It still sounded smooth, but not as ruck and warm as with the Alternate Audio. Vocals were more open-sounding and more effortless, if a touch lighter. On the Anonymous 4 disc, even though the vocals didn't sound as golden or sweet through the Classe, they were still very good. I could also hear the vocalists drawing breath at the ends of phrases more easily. More resolution, perhaps? Cymbals and high hat sounded sharper and gutsier and more prominent. When electric guitars were being picked on the Eagles or Metallica discs, they sounded sharper, and not as rounded and sweet as with the Alternate Audio amplifier, with a slightly noticeable distortion and grunge. The sound smoothed out quite a bit when I switched the Classe to balanced mode, the background became more silent, and the noise floor dropped. As far as reproducing the sound of electric guitars, the Classe sounded more real, if not as sweet as the Alternate Audio.
The CA35 is no slouch in the bass department, but it couldn't compete in this area with my Classe CA200. This is where system matching might come into play. In talking with one of my fellow auioMusings cohorts after we had both finished our reviews of the amplifier, I discovered he totally disagreed with me about the bass performance of the CA35. In his system, which includes a pair of ProAc Response 3.5's he found the bass fast, dynamic, and clean. He also had the Alternate Audio preamplifier in his system, which makes me think that maybe my Classe CP60 preamplifier is a mismatch with the CA35.
I really enjoyed listening to music through the CA35. The seductive sweetness and warmth of this amp kept overcoming my critical listening and letting the music flow through me. If you're interested in a single-ended solid state design, take the Alternate Audio CA35 for a spin and see what you find.
- Francisco Duran