Margules I-240 Integrated Amplifier | REVIEW

margules i-240 integrated amplifier

The Margules I-240 integrated amplifier seems so familiar to me, and not just because I’ve known the Margules family for over a decade and I’ve heard this particular model play a number of times at high-end audio shows. Look at it, a simple and basic tubed integrated amplifier, powered by EL34s (or KT77s or 6CA7s) and with 12AX7s in the preamp stage, producing a modest yet noticeably capable 25 watts per channel in pure class A. On paper it’s nearly identical to so many amplifiers I used to represent and sometimes use as a reference in my main system. The I-240 is basic as can be, almost old-fashioned, with only three line-level RCA inputs. It’s simple, but as I learned from running these amplifiers for many years, it’s usually all I ever need. Maybe that still applies in 2021.

There’s something special about the sound of the Margules I-240, however. I’ve noticed it. Grover Neville noticed he when he covered the room for T.H.E. Show back in June. It’s something that you pick up from listening to the whole system. Margules makes complete systems, amp and speakers and turntables and phono stages, and you usually you hear it, that special warmth, something that sounds so right and so easy and so hypnotic.

I’ve suspected all along that it’s this integrated amplifier that conjures this specific magic. I needed to find out for sure, so I asked for it shortly after I reviewed the LSA T-3 turntable—an OEM Margules design, by the way.

It’s not one of those integrated amplifiers like the Allnic Audio T-2000 or the Balanced Audio Technology VK-3500 integrated amplifiers that just got shipped out of here, big fairly expensive beasts that employ tubes in some configuration but sound so close to neutral that we should all just dispense with the valve vs. resistor debates for a spell. No, the Margules Audio I-240 is a tube amplifier and proud of it. I mean that in the nicest possible way, mostly because I think EL-34 amps are a little smoother and more linear than, say, a KT-88 based amplifier, which has more of that lush and romantic vibe going. The I-240 is far from mushy or wooly or soft. But it is warm, and that can be a comfy and tingly thing in high-end audio.

In other words, there’s no mistaking the I-240’s sound as that of anything but a tube amplifier. That’s a good thing, of course, a very good thing. I genuinely miss having this kind of integrated amplifier in my home system.

margules i-240
(photo courtesy of Grover Neville)

Margules I-240 “Basics”

The Margules I-240 integrated, as I mentioned, has 25 watts per channel (ultralinear). That’s a funny number for me these days—it wasn’t that long ago that high-end audio reviewers had to offer a caveat about such low-powered amps not working with certain inefficient or otherwise hard-to-drive loudspeakers. Heck, I remember Sam Tellig warning potential buyers of the B&K ST-140 power amp because it only had 70 watts per channel—why is probably why the ST-140 suddenly had 105 after the review.

But for me, 25 watts per channel can almost sound like a lot. When I was an importer, there were times I had five or six amplifiers sitting around, waiting for their turn, and not one of them had more than 25 watts per channel. I can work with that number. I won’t even blink.

I’ll only say that I used the Margules I-240 integrated amplifier with numerous speakers with differing sensitivities and impedances and not once did I feel the Margules was running out of steam. My Trenner & Friedl ART monitors (85 dB but 8 ohms) once scoffed at a 22 watt per channel tube integrated but were perfectly fine and relaxed with the I-240. In fact, I stuck with this rewarding combo for most of the review period.

Margules characterizes the I-240’s active servo circuit—and what makes it unique among tube integrated amps near its $6000 price point—this way:

“The unique characteristics of our proprietary active servo circuit makes the output stage always operate in pure class A without requiring polarization adjustments allowing the change of tubes without any modification. It also allows the use of different valves such as EL34, KT77, 6CA7, etc. giving the user the possibility to tune the unit to their liking.”

with the tube cages in place

The review sample of the Margules I-240 came with four EL34s, by the way, in addition to the four 12AU7s in the preamp section. Margules avoids the use of negative feedback in their amplifier designs, and they employ shunt power supplies because that approach won’t induce harmonics because it doesn’t use a control loop circuit. Margules also developed a “Back Electromotive Force Sensor” system which “changes the amplifier’s output impedance upon load requirement.”

Cosmetically, the Margules I-240 is gorgeous in a slightly understated way. Sure, you’ll notice those soft blue lights first, and the effect is slightly intoxicating. The wooden ply end-pieces are a nice touch. It’s a very attractive-looking integrated amplifier, even if it’s supposed to be “basic.” The included remote control, wooden to match those end-pieces, performed smoothly and consistently—especially with the attenuator.

The only unusual detail I noted was the selector knob on the top behind the front panel, which also doubles as an on-off button. You push it down to power it on (there’s also a rocker switch on the back panel if you’d prefer) and turn it to choose one of those three unbalanced inputs. It doesn’t go click-click-click between the inputs, it just sort of floats and spins freely. It’s cool and different, and that’s about it.

So while the Margules Audio I-240 integrated amplifier seems sort of basic on the outside, despite its pleasing aesthetics, it’s on the inside where you find the design philosophy of Julian Margules, the patriarch of the Margules family.

margules and ferrum

The Margules I-240, Now With ANA®

A few years ago I had a long discussion with Julian Margules at a high-end audio show about the philosophy behind his approach to sound. Some of you may be rolling your eyes right now, getting ready for another tale of audio mysticism, but Julian’s research into neuro-acoustics is science-based. Julian has been interested in the way we hear sounds, but not in the usual ways. In the real world, we are able to tell how far a sound is from where we are standing and which direction it’s coming from so we can instinctively know if we need to run and in which direction.

This research led Julian Margules to ANA®, which stands for neuro-acoustic alignment. (That’s translated from the Spanish, obviously, since Margules is located in Mexico City.)

“ANA® (Neuro-Acoustic Alignment) technology is a Margules innovation based on the way the human brain perceives sound by prioritizing harmonic structure over the fundamental pitch. This technology is about how we humans perceive sound, not how we measure it. This technological advance has its origin in the theory of seductive sound (engaging sound), our brain decodes information from sound waves through the ears: when the sounds are close, they keep us attentive due to the relationship that exists between the perception of these, the distance in which we perceive them and their intelligibility. Distant sounds, even when they are intelligible, do not attract our attention and are easily ignored.”

This proprietary ANA® technology results in lower distortion, with gains in harmonics and an “appropriate” frequency response that always sounds realistic to human ears. As both Grover and I found out, the Margules I-240 sound is extremely natural, on the warm side, but incredibly satisfying overall.

Again, this is not fairy dust that’s sprinkled on the PCB boards, but rather a holistic approach to amplifier design that decides which circuit topology and which test methodology is best suited for focusing on harmonic structures over fundamental tone. This is known as the concept of engaging sound, and Margules has a nifty summary of it on their website.

marc phillips system

Margules I-240 Set-Up

Once again I’m going to forego listing all the equipment that spend time in the ring with the Margules I-240 integrated amplifier, but I will focus on one or two system configurations where I truly enjoyed the sound.

My favorite set-up, which I’ve already mentioned, involved one of my longtime references, the Trenner & Friedl ART monitors (first generation). My love for the two speakers I actually own, the ARTs and the Brigadiers BA-2, were amplified by the presence of the magnificent Acora Acoustics SRS-G speaker stands, so it’s like getting all new speakers in for review. I also matched the I-240 with the Rosso Fiorentino Pienzas monitors from Italy.

I gravitated toward a very simple set-up, the ART/Acoras, the Margules I-240, and both my standard Technics SL-1200G rig and my other long-term reference Unison Research CDE player, all hooked up with Furutech and AudioQuest. Just to mix it up, the Ideon Ayazi Mk. II DAC with the 3R Master Time Black Star, a USB re-clocking platform, was used for streaming from Qobuz.

margules i-240 tube complement

Sound and Listening

It’s hard to listen to Julian Margules talk about “engaging sound and ANA” and then listen to a Margules Audio Group system and pretend you don’t hear the connection between the two. Grover encapsulated the Margules sound as “there’s just something about that system.” I concur. When the Margules I-240 was in my system, it was time to relax. Dig in. Focus your thoughts. Think about the music. Be present, at home, in the place where you want to be, doing the things you want to do.

For the first 100 hours or so, the Margules I-240 integrated amplifier did come off as warm and tubey—again, not a bad thing—but as the amplifier burned in just a little more, those initial impressions were slowly and methodically replaced with a feeling that no inner detail was harmed during the making of this music. This is not a sound that favors the warm fuzzies over imaging and soundstaging and sharp transients and all those other items on the old’ clipboard checklist for budding audiophiles. Warm eventually turned into natural, and that underlined the realism of the music. The longer I listened to the Margules I-240, the more I realized it wasn’t just an amp merely desired for its occasional fix of warm, classic tube sound.

Once again I’m going to bring up my 45rpm Impex reissue of Legrand Jazz, mostly because the Margules/Trenner & Friedl/Technics/Koetsu system turned out to be the hardware equivalent of its soulmate. This is a slightly tricky recording because it does celebrate its historical patina, its enduring vision of a lost moment in time suddenly recaptured for a fleeting moment. The Margules I-240 didn’t polish the sound with countless Snapchat filters, nor did it reveal all the ancient artifacts that can polarize some listeners. Instead I heard a recording where all the original energy and scale were preserved almost perfectly.

marc phillips system

Yes, the Margules I-240 loved to play vinyl. I used so many different phono pres with the Margules: the Brinkmann Edison Mk. II, the Pass Labs XP-27 and the Allnic Audio H-5500 and the Hagerman Audio Labs Trumpet MC. But the I-240 loved hi-rez digital through the Ideon Audio gear as well. Sometimes I go through fits of wanderlust and wind up in the vast and nebulous realm of electronica, really digging into Qobuz and looking for that next big thing that will tickle my fancy. It was fascinating to look back and forth between the simple valve-amp beauty of the Margules and the flow of digital sounds coming from my speakers. The Margules brought a bit of humanity back to the electronic sounds, adding textures and feeling and emotions that always felt right.

Ultimately, I felt that the Margules I-240 was happier playing more intimate types of music—jazz quartets, female voice, whatever can be described as somewhat less than bombastic. I could play music loud if I wanted to, and I never felt like I was pinned against that 25-watt ceiling above. But when we’re talking about ANA, those unexpected emotional connections that place harmonics over pure tone, the magic flowed effortlessly with the softer stuff.

But there’s a solution, one that I discovered, a story of two ships that passed in the night. That other ship was the TotalDAC d100 speakers, which are big horn-loaded towers that have two 12” woofers per side and an efficiency of 98 dB. This combination was only possible for a few days but it was glorious, which suggested that the Margules I-240 can give you everything you want if you hook it up to a big, easy-to-drive transducer that goes super deep in the bass while maintaining the I-240’s exquisite tonal balance.

margules i-240


My time with the Margules I-240 is branded with the idea that as time wore on, I liked it more and more. First: “I miss the sound of tube amplifiers like this one.” Second: “It’s not that warm and tubey—it does a lot of other things very well.” Final: “Wow, I’m going to really miss this amp and the wonderful and natural way it sounds. It’s a really great integrated for a reasonable price.”

It almost pains me to say that I would have preferred a couple of nods to modern amplifier technology such as maybe one balanced input, because just a couple of years ago I didn’t need any of that. I would have been extremely happy using RCA inputs for my DAC, along with any other digital sources I now use. When I think about it, though, there’s absolutely nothing this simple and relatively old-fashioned tube integrated amplifier can’t do for me right now, this second. Never mind.

So maybe Margules decides to build another integrated amplifier, one above the I-240, and maybe it’s got five pairs (XLR and RCA) of inputs. Maybe it’s got 50 watts per channel. Maybe you can flick a switch between triode and ultralinear. Maybe add a phono stage option since the existing Margules phono stage is excellent and affordable.

Or maybe you just keep this little gem as it is and bask in its natural and utterly realistic glow and spend the rest of your days thinking about neural acoustics and engaging sound instead of bells and whistles. Highly recommended, and a Reviewer’s Choice.

margules i-240 integrated wins the pta reviewer's choice

margules with hagerman

margules i-240

margules i-240

marc phillips system