MartinLogan Masterpiece Renaissance ESL 15A loudspeaker

I prefer and have owned electrostatic speakers for most of my audiophile life. Depending on your point of view, this makes me either the most qualified or the least appropriate writer to review MartinLogan's new electrostatic loudspeaker, the Masterpiece Renaissance ESL 15A.

Oh, I've flirted with dynamic speakers. I've owned and loved—and ultimately, when I was an audio retailer, sold—models from Revel, Thiel, Vandersteen, and many others, while my long-term choice has been electrostats. And while I've spent plenty of time with electrostatic speakers from Acoustat and Quad, I've ended up owning MartinLogans: Sequels, Quests, ReQuests, and, currently, Prodigys.

What attracts me to electrostatic speakers are the clarity, neutrality, and sense of "thereness" I hear from them, along with the natural cohesiveness of the imaging and midrange reproduction of tall, dipolar, line-source designs. The dispersion characteristics of electrostatic panels minimize sidewall reflections, and their lack of crossover electronics in the critical mid and high frequencies has always been a selling point for me. And I find the simplicity of electrostatic speaker design appealing when I compare it to the challenges of accurately producing robust sounds and images from a complicated array of multiple dynamic drivers of various sizes (which also inevitably drives up costs).

Still, every January in Las Vegas, at the Consumer Electronics Show, I'm reminded that there are some wonderful dynamic speakers out there: full-size models from MBL, Vienna Acoustics, Vivid, or YG Acoustics always impress me, and I'm sure there are others. These speakers also deliver that addictive life-size sound and sense of "you are there." And many of these top-tier speakers beat my MartinLogans in some important areas, such as the three-dimensionality of human voices. But oh, the prices!

So in the end, and when the reality of price is factored in, I prefer what large electrostatic panels can do when set up properly in my largish listening room (33' long by 23' wide by 11' high). They easily throw big, life-size soundstages with pinpoint imaging and decent depth, filling the room with life-size music. Of course, some big dynamic speakers can create just as big a sound, but I've never found one that could do in my room what, say, the MartinLogan Prodigys do for their price of $11,000/pair. Twice that price, sure—but getting that big-as-life, uncolored sound from a box speaker of similar price . . . ?

Then, at the 2016 CES, MartinLogan's new Masterpiece Renaissance ESL 15A was launched at a price of $24,995/pair—more than twice the price of my Prodigys (and their predecessors, ML's Summits). I had to wonder: Is the value still there? But ML has added a key new ingredient that might just justify that price: a built-in powered woofer system, designed to be integrated with Anthem Room Correction (ARC) software, which is included in MartinLogan's Perfect Bass Kit ($100). My curiosity was piqued. Arrangements were made. Review samples were sent.

The pair of Masterpiece Renaissance ESL 15As arrived via semi truck, on a pallet with a total weight of 300 lbs. Luckily, the driver took pity on me and agreed to use a pallet jack to wrangle them down our steep driveway and into the garage. But after deciding to unbox the speakers in the living room, I realized that I couldn't get their containers there all by myself—each box is almost as big as a phone booth, if you remember such things. So I headed a couple doors down, to ask our neighbor, a jiu-jitsu instructor, to help. Good thing he agreed—we had to execute some tricky maneuvers to get the unwieldy boxes through the front door and into the living room. My Prodigys are of similar size, but their panels can be detached from their woofer cabinets for moving and shipping—the Renaissance can't be dismantled. So we stood the boxes up on the carpet, carefully walked the speakers out of them, and dragged them roughly into place.

Pretty Is as Pretty Does
MartinLogan speakers have always been gorgeous to look at, and their semitransparent electrostatic panels help minimize the visual impact such large speakers might otherwise have. When Wes Phillips wrote about the MartinLogan SL3, in 1997, he noted his visitors' constant stream of compliments about the speakers' beauty, in addition to their wonderment about how they worked. The same thing happens at our house whenever new guests visit: They walk around the Prodigys, expressing admiration for their appearance. Then, invariably, their heads bobbing up and down as they examine the panels' full height, they ask, "Where does the sound come out?"

As interior design shifted from the oak and wood of the early 1980s to the industrial metals and color themes of today, MartinLogan's design aesthetic has evolved along with it. If you trace the evolution of ML designs over the last few decades—say, from the Sequel and Quest to the Prodigy and Summit, and now to the Renaissance—you'll see some patterns: The panel side rails have become leaner and apparently stiffer, the bass cabinet has become larger and more square, options of color and wood finish now abound, and the entire speaker has gained weight . . . and price. The natural endpoint (so far) of that evolution is the Renaissance, with clean lines, and carefully chosen proportions.

You'll also notice that, while very similar to earlier ML designs, subtle changes have been made in the electrostatic panels themselves, which now are made using ML's XStat technology. The precisely spaced holes in the carbon-steel stators on either side of the transparent Mylar diaphragm are now smaller, but also far greater in number, than in previous MartinLogans. Consequently, the stators now present less of an obstacle to the soundwaves produced by the diaphragm, as well as making the panels more visually transparent—and manufacturing processes have tightened the tolerances when setting in place those elements.

Backstory in Brief
Gayle Sanders, the founder of MartinLogan, has noted that designing an electrostatic panel is essentially "trying to control a lightning storm." Since so much has been written about how electrostatic technology works, and with the Internet allowing you to go as deep into it as you desire, I'll forgo most of the detail here except to point out that the technology goes back a century: some of the earliest loudspeaker experiments involved electrostatic diaphragms of pig intestines coated with gold leaf. That should get you interested.

MartinLogan's claim to fame was to figure out how to keep the two highly charged metal stators insulated as they tensioned the virtually massless sheet of Mylar sandwiched between them, also highly charged, into a smoothly curved surface—and keep it all that way. Sanders eventually came up with the solution, then collaborated with electronics engineer Ron Sutherland (now of Sutherland Engineering), who built the power supply to get the thing making noise. The name MartinLogan combines the middle names of Sanders and Sutherland.

Their first commercial loudspeaker, the Monolith, was released in 1983, and established MartinLogan's magic formula: a curved electrostatic panel atop a box containing a dynamic-cone woofer. Although ML also created electrostatic-only designs, such as the CLS, the electrostatic-panel-atop-dynamic-woofer hybrid proved the most popular of their speaker types because it combined the strengths of both technologies in a loudspeaker with a small footprint.

Thirty-three years after the Monolith comes the Masterpiece Renaissance ESL 15A, derived from that original recipe, with a 46" tall by 15" wide version of ML's latest-generation MicroPerf XStat panel mounted atop a bass enclosure with two 12" aluminum-cone dynamic drivers, each powered by its own 500W class-D amplifier.

The Masterpiece Renaissance ESL 15A, at just under 6' tall, is a couple fingers taller than the Prodigy, though the ESL panels in both speakers are 46" high. Where they differ is that the Renaissance is, at 15.75", slightly less wide even though its active panel area is wider than the Prodigy's, due to the thinner side rails holding the stators and diaphragm in place. This contributes to the new speaker's leaner, more elegant look. Altogether, the Renaissance has a total radiating area of 690 in2, tensioned into a curve with 30° worth of dispersion.

Those thinner rails are made of aerospace-grade, extruded aluminum alloy, and are said to be more rigid than their larger, wooden predecessors. Tapping my finger anywhere on the frame resulted in only a dull thud, with none of the ringing you might expect from a long metal bar.

The big difference between the new Masterpiece models and my Prodigys is the more voluminous enclosure for the new models' powered woofers—the bustle, as I lovingly call it—which, at 26" high by 15.75" wide by 24.9" deep, is the size of a modest subwoofer, and accounts for most of the speaker's mass. The top and side panels of the woofer enclosure are finished in the color or veneer of your choice. Mine came in Gloss Black and look stunning; you can also order Gloss White, Dark Cherry, or Walnut—or, for a bit more cash, one of seven Premium Finishes: Rosso Fuoco, Cordoba Red, Deep Sea Blue, Basalt Black, Meteor Grey, Desert Silver, or Arctic Silver.


Along the bottom of the rear panel, below the grille of the rear-firing woofer, are the controls and connections. Starting at the left: First is the ARC Setup Speaker Link—an Ethernet connector for connecting the two speakers to each other when running room correction. Then come a small USB Mini-B jack labeled ARC Setup Input (more about that below) and a small ARC status LED. Next to that is a switch that lets you turn ARC on or off, and at the center are two wide-spaced WBT binding posts. To the right of those is the Mid-Bass Level switch, with settings of –2, 0, and +2dB, followed by a Speaker Status light that glows red when the ESL 15As are plugged in but not active, or green when they're playing. Last are a Bass Level knob that runs from –10 to +10dB, and a Light switch to turn the speaker's light On, Off, or Dim. Below that is the IEC AC power jack.

The Light switch controls a row of white LEDs along the bottom of the speaker's front grille. Though not bright enough to be visible during the day, they provided a nice glow at night when set to Dim. At least you have an option here, especially if using the speakers in a home theater, where you'll probably want the LEDs turned off.

Where you don't have an option is with the ESL 15A's signal-sensing power supply, which puts the speaker into standby when not in use for several minutes. It takes only a couple seconds to recharge the panels when the music starts up again, but that's just long enough to make you want to restart the first song. I asked MartinLogan if this could somehow be bypassed, but no dice. And when the speakers turn themselves on, the subs emit a soft clack-clack. The Prodigy's panels are always on, so long as the speaker is plugged into the wall, so it's always ready to play at the first note. ML explains that the primary purpose of the Renaissance's sensing circuitry is to prevent dust from being attracted to the charged panels. Oh well.


All About That Bass
The ELS 15A's front- and rear-firing 12" woofers are protected by flat, removable, semitransparent metal grilles that resemble the stator panels. Under the woofers is a tray that contains the electronics for the crossover (which kicks in at 300Hz), the power supply for the electrostatic panel, the ARC-2 circuitry, and one 500W class-D amp for each woofer. At the heart of the electronics is the proprietary 24-bit Vojtko DSP Engine, which works to control the low-pass filters and perform equalization and limiting processes on the woofers. This came in handy in optimizing the ESL 15A's bottom end for my room, as we'll see.

2101 Delaware Street
Lawrence, KS 66046
(785) 749-0133

emcdade's picture

Absolutely gorgeous. I love that they sloped the woofer cabinet to the back, it reminds me of a Range Rover roof-line. It really is a nice touch to get away from a boxy look that dual opposed woofers demand.

I'm a bit jealous but thankful this line has arrived, as with current models on closeout I snatched up a pair of Montis at a very steep discount!

After seeing that in room frequency response I'm going to be very tempted put some EQ in my chain, and it looks like Dirac will have to be my weapon of choice since it can EQ from say 200hz on down and leave the mids and highs alone.

Are you keeping them John? After seeing that FR plot I don't think you're going to do better if you want ruler flat!!!

Jon Iverson's picture
Don't have the money for them at the moment. But if I did, yes I would buy the Renaissance and replace the Prodigy. And keep the extra subs just for fun.
brenro's picture

I've been dying to see a review of these speakers and this is a very good one. They acquitted themselves well but I'm having a hard time seeing twenty five thousand reasons to part with my Prodigies.

ctsooner's picture

JA interesting measurements on this beautiful speaker. Over the years of reading your measurements, I have noticed when the speaker under test was a panel type (Martin Logan, Magnipan , MBL) or horn loaded, the waterfall plot has a lot of hash in the foreground. I've always wondered if this sounds anything like singing in the shower or using the echo effect on a Karaoke box being a lot of delayed energy, quite even in frequency for quite some time. Thanks for putting in the effort to measure speakers because it is quite rare today and I enjoy seeing how they correlate to their sound.

ottablue's picture

Very nice review!!! Have a question on BASS. The Renaissance speaker has Frequency Response 22–21,000 Hz ±3dB with double 12" woofers and older model Summit X has Frequency Response 24–23,000 Hz ±3dB with double 10" that is only 2 HZ difference!!! So would I expect very similar bass? Will I still need subwoofers with Renaissance speakers since with Summit X I don't FEEL (lack of tactile presence) much bass thus using 2 subs!! Thank you.

tejastiger61's picture

Jon .. A million thanks for your effort.. and review. My only wish is that you had documented your effort with a I-phone(or device of your choice)and let the general public.. see with a video (what a few snapshots that will barely show) the muscle and doe ray me, required to enjoy these fine ELS15A's.
I am begging you to document the re-boxing of these whoppers. And the effort required just to send them back. It is after all is said and done "only fair" to would be purchasers to see what they are getting into coming and geauxing It will prove my theory that yawls job is not all ooh's and ahhhh's .. it is hard work at some point.. or the other.

Oh yea how much is the shipping cost..?

BruceW's picture


I think you got that part wrong. During the "Prodigy era" I believe several models had signal sensing to power off the bias on the panels.

"Prodigy manual
page 22 FAQ
Will my electric bill go ‘sky high’ by leaving my speakers plugged in all the time?

No. A pair of MartinLogans will draw about 5 watts maximum.
There is some circuitry to turn off the static charge when not in use; however, the actual consumption will remain close to the same.

The primary purpose of the sensing circuitry is to prevent dust collection on the electrostatic element."

Speaking of transparency, I found when I by passed the woofer crossovers and used a much steeper (24 db/octave) slope to get the woofers out of the way, transparency up leveled dramatically.

By passing all the passive components to the stats made a further dramatic improvement.