Proper care and feeding. We all need it and loudspeakers are no different.
The Alta Audio Io were new to me when they first showed up in Barn many months ago but we have since become friends. Unlike some review stuff, but like many people, it took me time to get to know the Io. This is in part due to the nature of a loudspeaker where one can only know one as a couple, i.e. when paired with amplification. Sometimes, perhaps most times, this pairing can determine what a speaker “sounds like” which is to say speakers do not sound like anything on their own.
I know, obvious stuff but sometimes a review can lead the reader to believe that they will get the exact same results as the reviewer with a given loudspeaker—all one need do is buy it. While this cannot be further from the reality, ideally a review can give you a good idea about those aspects of a loudspeaker’s ‘sound’ that remain constant while the amplifier in-use does not. While we’re here in system-ville, my totaldac D-1 seven and dCS Network Bridge acted as my digital front end for this review.
I talked about the Alta Audio Io in my review of the Quad VA-One where I said, “The Io present music with more flesh, blood, and bones as compared to the ELACs, making for a more moving musical experience.” The Io also had a run with the NAD D 3020 in that review where I found, “The Altas are smooth operators and weighted toward the meatier side of the sonic spectrum. I would put the NAD D 3020 in a similar category with a de-emphasis on bright which in this case did not make for an ideal pairing.”
As I played with the Io over months, I also paired them with the PS Audio Sprout100 which proved to be a very nice mate. The little Sprout is more of a clear drink of water as compared to the little NAD D 3020 which I’ve come to learn serves the Io’s character very well. This may sound odd when taking the positive results I got with Quad VA-One but hifi, like life, can be complicated. Kidding aside, the little Quad is wonderful amp and it mated very well with most of the speaker it played with. I would note that when we read about “tube sound” it means about as much as “good coffee.”
Here are the Io vitals: One 2 inch ribbon tweeter, one 7 inch midrange/woofer, 87.5 dB / 2.83 Volts @ 1 Meter sensitivity, a 4 ohm impedance, and a claimed frequency response of 42Hz to 47kHz. What those numbers don’t tell you, they can’t, is the Alta Io are full-bodied, rich, and warm. They are decidedly not detail fiends and they never sounded ‘hot’ regardless of the amplifier in question. Dare I say their presentation is relaxed but this trait can vary with amplification (the NAD made them sound too relaxed).
My Leben CS600 has a multi output impedance selector (a knob) that allows for 4, 6, 8, and 16 ohm output impedance. I turned that knob to “4” and was greeted with a super-fine pairing, offering the control of the little Sprout coupled with the lovely texture and color of the Quad. The Leben / Io pairing was not as meaty-sounding as little Quad because the Leben better controlled the Io’s bass output. I happen to think the Leben CS600 is one fine-sounding amplifier, it is our Product of the Year for 2018, and it really made the Alta Io sing. They sounded more alive than with any other pairing (so far) and one really nice quality of this combination was its ability to play at low levels. Of course the Leben was perfectly capable of pushing the Io to Barn-rattling heights but I don’t rattle the Barn very often and more times than not I listen at moderate levels. The Leben allowed the Io to sound rich, colorful, and nicely textured even at moderate levels, more so than any of the other amplifiers. In terms of system building, budget be damned, this puts the Leben at the top of my recommended list for the Alta Audio Io (so far).
A Brief Note On Cables
The Alta Io offer two sets of binding posts for bi-amping the ribbon tweeter and midrange/woofer. When not bi-ing, Alta includes binding clips so you can use regular old speaker cables. For the purposes of the Alta review, I got a pair of AudioQuest Rocket 33 BiWire speaker cables ($389.99/10ft. pair) because I heard they can offer an an improvement over the clips. Compared to my Tellurium Q Black II speaker cables, the Rocket 33s did in fact improve the sound of music, relieving what I was hearing as a touch of hardness. Without trying the Rockets, I may have attributed “hardness” to the Alta Io. And I would have been wrong.
Back to the review, Alta Audio says the Io “requires 50 to 150 Watts per channel” so my findings did not follow this rule seeing as the Leben pumps out a mere 28 watts into 8 ohms. So much for rules. But I was curious—what would the Io sound like with more power? Enter the Mytek Brooklyn Amp. Ive heard the Brooklyn Amp at a number of shows and let’s just say I wanted to hear them in-Barn and Mytek was kind enough to send it along. The little Brooklyn is a Class D amp and rated at 300 watts into 4 ohms so I was thinking—that should do the trick. And it did.
Using my totaldac as both DAC and preamplifier running directly into the Brooklyn Amp made for an even more incisive and powerful yet über-controlled sound. There was gobs of sparkle from that ribbon tweeter, more than with any other amplifier, and the Io no longer sounded relaxed. They sounded ready. My final few weeks listening to the Io were spent with the Mytek Amp in the Neverland of musical delight. Big, boisterous, and bouncy music was well-served so City Girls, Stravinsky, Funkadelic, Marie Davidson, and others saw plenty of air time. The Io do detail but they never approach harshness or etch and that (relatively) large mid-woofer adds enough body to keep music sounding solid so overall you get refined but meaty making finer music like Fennesz’s Black Sea, Arvo Pärt, Julianna Barwick, Hatis Noit, and Julia Kent gripping. Nice.
Of course we cannot ignore the role the totaldac played in this sound picture but that’s the nature of reviews. That being said, after putting the Alta’s through their paces with five different amplifiers I feel confident in saying that the Alta Audio Io offer a physical, meaty, and full-bodied sound that is also nuanced and delicate where called for. Think rich.
It took me some time to get to know the Alta Audio Io, when doesn’t it take time when it comes to hifi (especially speakers and people), but it was time very well spent. I found that with proper care and feeding, the Alta’s can sing with a voice that serves music in any and all its forms and that, my friends, is exactly what any loudspeaker needs to offer.
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Huntington, NY 11743