MartinLogan Purity: HiFi with ease!

By Jeff Dorgay

Purity_Dark_Chery_Lifestyle_2In the last few years, MartinLogan has received a lot of praise for their hybrid electrostatic designs, mating their legendary electrostatic panel to a dynamic woofer. In the case of the Purity, it’s a pair of 6.5-inch woofers in a very compact package that will only take a 10 x 15 inch patch of your living area.

What makes the Purity special though, is the fact that these are powered speakers, so you only need a source component and a pair of fairly long interconnects to build a complete system! These speakers feature a 200-watt, high resolution, switching amplifier built in, so if you want high quality HiFi, but don’t want a rack full of gear to go along with it, the Purity is for you. You can even run them with an iPod or Squeezebox and have the ultimate minimalist system. The Purity can be customized for different color options, at a base price of $3,295.

Small sources

That’s exactly where I started my journey with the Purity. In my small (11 x 17 foot) living room with my iPod full of Apple Lossless files and a pair of 8 foot Radio Shack interconnects. Worth noting when you set the Purity up for the first time, there is a hard plastic base on the bottom of the speakers that will tilt the speakers’ electrostatic panel back somewhat or keep it straight up.

Pay careful attention to this adjustment, because tilting them back gives the speaker a better overall tonal balance if you are going to be listening to the speakers primarily walking around the room or mostly standing. If you are going to be more of a traditional audiophile, listening in your chair, stand them straight up. Note, that with either of these positions, you will lose some of the high frequency and focus when you are not in the optimum listening position.

Tech info

If you’ve got a high quality source, you will be floored at how good the Purity sounds and how much music comes out of these relatively small speakers. I’m guessing you will be in one of two camps: A legacy MartinLogan owner that needs another pair for a different room in your home or office or someone new to the MartinLogan way of doing things.

If you are new to the electrostatic speaker experience, you’ll be surprised at how open and airy these speakers sound compared to a lot of box speakers, and that’s MartinLogan’s trademark. The diaphragm inside the panel assembly weighs close to nothing, so it can accelerate instantly. Thanks to the crossover frequency being so low (450hz) this panel handles most of the critical musical information and the two small woofers give you the same amount of bass you would get with a larger woofer, but in a smaller space. Those two small woofers also move faster, to keep up with the panel, adding to the overall transparency of the sound.
If you’re already a MartinLogan owner, you know all this stuff and you probably want to know how the Purity compares to the larger speakers you already own. The actual panel in the Purity uses the same materials and construction as the rest of the MartinLogan line (all the way up to the flagship CLX, which is one of my reference speakers), featuring their 2nd generation electrostat panel technology.


Even using my iPod as a source, I was very impressed with the sound of the Purity. Think of the Purity as a bite-sized serving of what the CLX has to offer. When sitting in the sweet spot, it’s easy to be fooled at first listen that you aren’t hearing something much more expensive than the Purity and that’s it’s best attribute.

Granted, a switching amplifier has some limitations and because of the two 6.5 inch woofers, these speakers will reproduce solid bass down to about 40hz, where MartinLogans’ larger speakers will go all the way down to the mid 20’s, the overall balance is excellent.

As a MartinLogan owner, I was excited at just how much sound I could coax out of these speakers. After quite a bit of iPod listening, my next task was to investigate the limits of performance these speakers were capable of, so my next task was to drag out some better interconnects, power cords and source components to find out if this was a serious HiFi speaker after all.

Upping the ante

Again, the Purity passed with flying colors. Now, my “budget” system consisted of the Audio Research SP-17 preamplifier that we had in for review along with the Marantz K-A1 Pearl CD/SACD player. Both of these components cost almost as much as the Purity, and I did upgrade from Radio Shack interconnects to two pair of ED422 interconnects from Empirical Design, valued at about $500 each. I swapped the stock power cords from the Purities for a pair of Shunyata Venom cables ($125 each) and plugged the whole system into a Running Springs Haley power conditioner.Purity_Front_3Quarter

Bottom line, the Purity is up to the task of being the cornerstone of a real “audiophile” system too, so even if you start out just using the Purity with an iPod, you can rest assured that if the upgrade bug bites, you can grow with these speakers.

The Sound

The sound is pure MartinLogan. Open, airy highs, walk through midrange and tight punchy bass. I kept going back and forth between my dedicated listening room where the CLX’s make up a six-figure system and the Purity in my living room with the ARC/Marantz combination, playing the same CD’s on each.

The Purity did a fantastic job with everything I played. My favorite rock records had plenty of body and of course, vocal records really let these speakers shine. At times, you could definitely hear the limitations of the switching amplifiers present in the Purity, but that was only when comparing the system to my reference system. I think MartinLogan has done a great job with integrating the amp and speakers.

When playing musical selections that did not possess huge dynamic swings or subterranean bass notes, it was easy to be fooled when going between rooms. I was surprised at how good the speakers’ bass response was, considering the printed spec lists the LF response at 41hz. Yep, the driving bass line in “In-A-Gadda-Da-Vida” came through loud and clear. Speaking of loud, these babies did a great job with my favorite Mastodon, Tool and Metallica cuts, so they should be able to play anything else that interests you after this torture test.

While the Purity does not have the full scale of dynamic range that the more expensive Vantage or Spire possess, it does one thing better than most of the speakers in the MartinLogan line; top to bottom coherency. Those small woofers are fast and articulate. So much so, that you might be fooled into thinking this is a full range electrostat!

The only real limitation to the Purity is that the sweet spot for critical listening is small. If you have them angled back, the sound is very good all over the room, but the best sound will only be in one spot. Same thing if you have them optimized for your chair; that will be the only place you get all of the magic. Keep in mind you would have the same limitations with a small pair of mini monitors in this kind of space too, so I don’t see this as a limitation.

I also made it a point to run some fairly long interconnects to these speakers, as they only have RCA line-levelinputs. While I didn’t have any trouble with 20 foot interconnects, it might be a good idea for the next version of these to have balanced XLR inputs as well. Those with a budget source only possessing speaker level outputs can connect via the speaker level inputs as well.

In the end, convenience

Thanks to the internal power of the MartinLogan Purity, they make a great place to put a high quality sound system, where you might not have in the past. In five minutes you can have them set up and playing music and that’s what it’s all about. Though some of you might get grumpy that a powered speaker doesn’t give you the flexibility to choose amplifiers, speakers, etc., you’re missing the point; the Purity is the perfect speaker for someone who doesn’t want to bother with all of that! Plug em in and enjoy.

Because the Purity offers this level of performance, style and simplicity in one package at such a great price, we are awarding it one of our Publishers’ Choice awards for 2009.

The MartinLogan Purity
MSRP: $3,295


Sources: iPod Touch, Audio Research SP-17 preamplifier, Marantz K1 Pearl SACD player

Cable: Empirical Design ED 422 interconnects, Shunyata Venom Power Cables

Accessories: Running Springs Haley power conditioner