Moving Up the ARC Chain: Some Observations

Over the past six months I’ve moved up the ARC chain, replacing my amp and preamp and substantially improving the sound of my system. Since there may be others contemplating a similar upgrade path within the ARC lineup, I thought it might be helpful to share my experience. My purpose is not to write a formal review of any of these products. Nor is it my purpose to contrast any of these products with others that I considered since I did not audition products from other lines in my system before selecting the ARC gear. I did, however, research and give consideration to a number of other options—some suggested to me by Lou Hinkley who designs and builds my Daedalus DA-1.1 loudspeakers—but in the end decided to stick with Audio Research for a number of reasons. First, I have had really positive experiences working with ARC. They stand behind their products, offer excellent and prompt service when I’ve needed it and build good quality gear. In addition, some of the amplifiers recommended to me would not work in my application, where electronics are housed in an entertainment center that provides somewhat limited ventilation. Both the Modwright KWA150 and the Clayton S-40 recommended by Lou and others operate a high temperatures and the Modwright is physically too large to fit inside my cabinet. I also looked at a number of Class D designs like the new Bel Canto Ref 1000MkII’s and Channel Islands D500MkII’s, which would run cool and save electricity but could not produce the kind of current that the DA-1.1’s like to see.

I had been using an ARC SP16 and 100.2 to drive a pair of Harbeth Compact 7’s for a number of years and was very pleased with the results. However, the 100.2 ran too hot inside our new entertainment center and so it was replaced with a 150.2, a Class T switching amp that never even ran warm to the touch. I was reluctant to give up the revered 100.2—it was a great sounding amp. Inserting the 150.2 I gave up some texture, dynamics and three dimensionality but not as much as I had initially feared. The 150.2 is a darn good amp for the money. It is just not quite at the same level as the 100.2, which sounded more like real music when driving the Compact 7s.

A few years ago I sold my Harbeth’s and moved to the larger, multiway original Daedalus DA-1’s and ran with the SP16/150.2 combination for a while, concentrating my audio dollars on upgrading my CD playback by purchasing a Naim CDX2 and then an Esoteric X-03se. However, once I moved to Lou’s new DA-1.1’s, I began to thirst for better electronics to get as much performance as I could out of the newer Daedalus models, which are considerably better across the board than the originals. (If people are interested I have a review posted on this site where I compare the original DA-1’s with the new DA-1.1’s that was written when I had this pairing of electronics).

I began with the preamp since I had deduced that the phonostage of the SP16 was a weak link in my system. This was not only the opinion of many who I spoke with and whose comments I read online, but also verified by experience—once I inserted the X-03SE in my system I simply didn’t want to listen to records much anymore—my digital front end simply sounded so much better than my Scout/JMW/Dynavector 20XM through the SP16 phonostage. I decided to go to separates—a linestage and phonostage—primarily to enhance the performance of my vinyl playback. Back in December I was able to pick up an LS26 (I have yet to get a new phonostage) and it was very interesting to compare the linestage performance of the SP16 with the LS26.

The LS26 shocked me. I thought the linestage of the SP16 was pretty good but was unprepared for what the LS26 could do. With the LS26 in my system I perceived much lower levels of distortion—I could play music louder without strain. The soundstage become more expansive in depth and width and the performers more easily localized within the soundstage. Frequency extremes were handled much better and there was much higher resolution of fine detail and instrumental lines. The LS26 was also much more dynamic and nimble. Tonally, the SP16 has a little more of that tubelike warmth and the LS26 is more neutral. Since my DA-1.1’s lean a little to the warm side this neutrality was a welcome improvement however I could see where someone with a leaner sounding system might like the bit of added warmth the SP16 delivers (all else being equal, which is not at all the case). I really wasn’t expecting this kind of improvement. The differences were not subtle—they were rather dramatic. Couple this with the enhanced features, build quality and ergonomics of the LS26 and this is a recommendation that I have no trouble making. The LS26 is well worth the additional cost. This is easily a linestage preamp I could live with for the duration. (Famous last words but it seems true enough for the moment!)

With the LS 26 in my system I turned my attention to amplification. As I mentioned, I thought long and hard about stepping outside the line based on a number of recommendations. However, ARC’s most recent solid state amplifier, the SD135, had caught my attention since it provided prodigious amounts of current (three times more than the 150.2), was an analogue design that was built like a tank and ran cool due to the incorporation of two low speed fans that move air across the output devices. One showed up on the Audiogon and, despite the fact that I could find no published reviews or even internet commentary, I bought it thinking I would give it a try and, if it didn’t work out, could sell it with minimal loss. Part of the allure was being able to stay within the ARC family and knowing that the unit would mate nicely with my LS26. I also had developed a nice rapport with the seller who had experience with the 100.2 (which I knew) and who really felt that the SD135 was superior across the board and a surprisingly unheralded performer.

Everything he said was true and then some---the SD135 is a phenomenal amp. While going from the SP16 to the LS26 was a considerable jump in performance the shift from the 150.2 to the SD135, in my system, was a giant leap forward. The SD135 provides much more realistic dynamics, is very quick and much better able to distinguish individual instrumental lines within the overall fabric of the music. This is one engaging amplifier that never fatigues the listener. It is like listening to a much more coherent speaker—from top to bottom the amp just sounds “right”. The 150.2, by comparison, has (a now) noticeable glare in the upper midrange and instrumental textures are much less convincing. The SD135 has much denser texture, tonality and warmth. The SD135 also throws a much deeper and wider soundstage. It is more layered—I’d say there are three layers of depth added with the new amp. Frequency extremes, particularly on the low end, are much more convincing. Bass is much deeper and tighter. Drums take on unique characteristics depending on their size and how they are struck. Overall, the SD135 is a much more musically involving amplifier that places the musicians in your room and draws you into the performance. The amp is also built like a tank and has a massive transformer that skews the weight toward the rear of the unit. The fans, which cannot be heard unless you put your ear about three feet from the unit and never while the music is playing, keep things running barely warm to the touch.

Overall each of these upgrades has yielded very satisfactory results. While the LS26 bettered the SP16 markedly, the SD135 simply trounced the 150.2—these amps are simply not in the same league. It will be interesting to see whether any of the review publications give the SD135 a spin—I’d particularly love to see how it might compare to the 100.2, which has achieved something of a cult status among the ARC solid state offerings. I feel that I have a good thing going with the ARC amp and preamp working synergistically in my system. While there may be other combinations that would produce slightly better sound with my DA-1.1’s, I appreciate having both good sound and a great company backing it up should I need any support. Besides, I’m not sure how much better things could get given what I’m hearing with the LS26/SD135.