By It may not be widely known, but Class-D amplification has been around in one form or another since the 1950s. Credit is generally given to British engineer Alex Reeves, who invented pulse code modulation, which today is known as PCM. Towards the end of the 1950s, Reeves developed the concept of having a PCM amplifier convert an analog signal into a switching signal, thus essentially creating the amplifier classification we know as Class-D.
Respectfully, at the time, this new technology sounded pretty dreadful by audiophile standards.By the mid-to-late 1960s, much work had been done to improve Class-D amplification for a more pleasing sound, and a potential alternative to SET analog tube amplifiers, as well as Class-A and Class-AB amplification. It wasn’t until the 1990s that Class-D began to enjoy even a small measure of commercial success. The first time I heard a Class-D amp, I thought it sounded terrible, and I wrote the technology off – permanently. Not surprisingly, research and development on Class-D continued. Any number of scientists, perhaps most notably Bruno Putzeys (learn more here), through his efforts at both the Hypex and Purifi companies he founded or co-founded, improved Class-D amplification and brought it into the modern era. Putzeys, along with others, improved the methodology of how Class-D operates as a digital switching amp. However, Putzeys’ designs are not necessarily using GaN circuitry. It is his work in meaningful operational improvements in Class-D, partnered with the adaptation of GaN, where this combined amplifier technology becomes much better as an audiophile product. Let’s take a look at the concept of GaN in a little closer detail.
So What Exactly is the Gallium Nitride Variant of Class-D Amplification?
In very simple terms, this new type of Class-D amplifier uses gallium nitride semiconductor technology (learn more here) as a replacement for traditional silicon-based MOSFET circuitry.This led to improved semiconductors, which led to better power supplies and, in a roundabout way, improved Class-D amplification. And separately, the incorporation of GaN semiconductors in place of the traditional silicon-based iterations gave us today what we know as Class-D Gallium Nitride amplification. This leads us to the ArgentPur IBIS stereo amplifier.
What Makes the ArgentPur IBIS GaN Amplifier So Special?
- It is impossible not to notice the compact size and waif-like weight of the ArgentPur IBIS stereo amplifier. As one who is accustomed to slinging 100-pound-plus amps around, or trying my best to do so (normally with movers), I find the small size and light weight of the IBIS a real pleasure. Picking up and carrying a stereo amplifier with one hand is a joyful experience, and one I have never before been afforded. For anyone with a space problem, or a back problem, this is an amplifier worthy of consideration.
- The ArgentPur IBIS collaborates with Orchard Audio and uses their Audio 25 GaN modules. However, the remainder of the build is based on ArgentPur’s own designs.
- The ArgentPur IBIS is listed at 150 WPC at eight ohms, 200 WPC at four ohms and 100 WPC at two ohms. Having even a capability for two ohms is impressive, as there are very few speakers available today with the nearly impossible to drive two-ohm load.
- All internal wiring is comprised of ArgentPur’s own solid silver conductors, encased in Teflon tube wiring. This configuration is consistent with the audio and power cords ArgentPur also manufactures.
- To complete the silver design, the connectors are silver-plated and even the solder used internally is silver. Silver is not a cheap material to work with, friends.
- Mundorf capacitors are used in the signal path. ArgentPur claims this provides sonics on par with Class-A, but without the heat and inefficiency.
- Small size notwithstanding, I found the build quality to be absolutely first rate, when most others in the class cannot say the same. When I first removed the ArgentPur IBIS from its very impressive orange Pelican Flight case, my first thought was how well-built the amp really was.
Why Should You Care About the ArgentPur IBIS Stereo Amplifier?
Not all audiophiles have the space, the overall system components, and certainly not the financial resources for a world-class, cost-no-object audio system. What the ArgentPur IBIS provides is exceptional sonics and, by exceptional, I mean surprisingly so: a compact size to allow usage almost anywhere, little to no heat produced (unlike Class-A) and, perhaps best of all, the cost of ownership is very agreeable. You are getting so much of the best amplification that the world knows for a tiny fraction of the price. That will make any audiophile care.
Some Things You May Not Like About the ArgentPur IBIS Stereo Amplifier
- On the rear-mounted connections, the IEC electrical input is on the right side of the rear chassis. The XLR and RCA inputs are in the middle and the left side of the chassis. Anyone like myself who routs their speaker cables in from both sides will have difficulty connecting the right speaker cable because the IEC inlet is simply in the way. I would rather see the IEC inlet in the middle of the chassis and the left and right RCA and XLR connections on either side.
- I must believe this is done as a cost-saving measure, but it would be nice to see a small pilot light on the front just to confirm the unit is, in fact, powered up. Who doesn’t like a small pilot light on an audiophile component?
Listening With the ArgentPur IBIS Stereo Amplifier
Despite the accolades our publisher Jerry Del Colliano and other staff members have so effusively provided, I was still quite suspect of Class-D GaN amplification. I knew the time had come for me to set aside any preconceived notions or concerns I might have regarding this new technology. So, when the offer for a review was made, I accepted – and I am very glad I did. I found the ArgentPur IBIS to sound surprisingly excellent despite the cost, despite the size, and absolutely despite any concerns or trepidation I may have had regarding GaN. For the record, GaN as a technology, and the ArgentPur IBIS specifically, are very impressive.
One highlight ArgentPur claims is an excellent bass presentation. As it so happens, I have a recently installed line array of six (three per side) REL S/550 (read review here) subwoofers in my audio room and I have been developing a playlist of music with exceptional bass tracks. In general, I found the bass was indeed quite powerful, more so than I expected, and was very tightly controlled throughout my list of bass-predominant tracks. I did not notice any blurring or smearing, any boominess, or compromised low-frequency presentation. In fact, I found the low frequencies to be perfectly enjoyable.
In the opening of Steve Winwood’s globally successful hit, “Higher Love,” from the album Back in the High Life, it would be fair to say the drum intro is the result of a fortunate mistake. After recording the initial drum track, drummer JR Robinson was waiting for the recording session to proceed. While what might best be described as fooling around, Robinson played a drum fill that, unbeknownst to him, was being recorded. Playing the two recordings back in different time signatures rendered a low-frequency drum riff coupled to a high-pitch rimshot, which actually sounds like timbales. This innovative drum track may be difficult for some amps to faithfully recreate. With the excellent bass response partnered with the higher-frequency reproduction from the ArgentPur IBIS, this seemingly innocuous intro sounds magnificent. In fact, this sound signature flows in and out of the track and along with a catchy, upbeat tune, makes this song the toe-tapping monster hit it was. The ArgentPur IBIS had no difficulty in portraying all the subtleties in the recording, as well as delivering the pulsing beat that made the song a worldwide hit.
Rolling Stone ranked it 446 out of 500 in their list of greatest songs of all time. Appearing on his second release, the Wild, the Innocent and the E Street Shuffle, “Rosalita (Won’t You Come Out Tonight)” is a raucous, high-energy, high-octane track that came at a time when Bruce Springsteen was singing about girls and driving “Chevy Stock Super 8s.” With a commanding drum track, a very lively piano, powerful guitar work by the Boss, and the ever-present saxophone excellence by Clarence Clemons, “Rosalita” is perhaps my all-time favorite Springsteen song. While the overall recording is marginal, the ArgentPur IBIS did an exemplary job of portraying the music and getting out of the way. With lyrics like “Well, tell him this is his last chance to get his daughter in a fine romance/Because the record company, Rosie, just gave me a big advance,” I want to crank it up and become absorbed by the song. The ArgentPur IBIS allowed me to enjoy this song the way it should be enjoyed.
Will the ArgentPur IBIS Amp Hold its Value?
This is an interesting question. The ability of this amp to hold its value is, generally speaking, based on the future prospects of Gallium Nitride as an amplification choice. Given how the technology is winning over consumers, I’ll go out on a limb and say GaN will be around for quite a while and will only gain in popularity. When the cost of ownership is factored against the performance, ease of use, and small footprint, I do not really see any significant downsides. If the technology improves as it has in recent years, the sky’s the limit on GaN as an amplifier technology. Even today, it can be the linchpin for a very affordable audio system and, best of all, one with shockingly excellent sonics. So, will it hold its value? Time will tell, but in my estimation, it absolutely will.
What is the Competition for the ArgentPur IBIS Amplifier?
Is it even fair to mention Orchard Audio as a competitor? They are one of the leaders in this technology, and ArgentPur is even using Orchard Audio’s GaN modules in the IBIS amplifier. However, it seems only natural to list the Starkrimson Stereo Ultra 25 at a retail cost of $2,899.95. Both amps are, in fact, nearly identical in cost. The main difference is the internal wiring, which on the ArgentPur is their own design of solid silver conductors, encased in a Teflon tube as a shielding device. I would also say the casework on the ArgentPur has a better visual look. While differing opinions on this are a certainty, I prefer the brushed aluminum look of the ArgentPur, as opposed to the anodized look of the Orchard Audio. Others obviously may feel differently.
When staff reviewer Michael Zisserson reviewed the AGD Tempo di GaN amplifier (read review here) in November 2023, he liked it so absolutely, he called it a “total rethinking of how an audiophile amp works, as well as how it fits in a modern stereo system.” While the AGD is more costly, retailing today at $5,550, the brand is perhaps one of the leaders and a prominent voice in the promotion of GaN as a worthy replacement for Class-A and Class-AB amplifiers. Rated at 200 WPC at eight ohms, and 400 WPC at four ohms, bridgeable for monoblock use with an output of 400 watts at four ohms, the AGD was nominated for a 2023 Future Audiophile Gear of the Year Award (read all the nominees here). Rear-mounted connections include both XLR and RCA inputs. Like most amplifiers, the AGD Tempo di has loudspeaker binding posts capable of accepting spade or banana terminals, or even bare wire if preferred.
My last comparison, and one about which I am still undecided, is my own reference amplifier, the T+A A3000HV (read review here). Initially, I did not feel this was a fair comparison, given the difference in price, performance and my own bias of how exceptional an amplifier the A3000HV really is. However, after disconnecting the T+A, and struggling to move it out of the way, I must admit I developed an intense curiosity as to how these two amps would compare. I had no firsthand experience with GaN technology. I only knew what I had heard from others, namely the various Future Audiophile staff members who had put a GaN amplifier into their systems. I decided therefore to include a direct comparison to my T+A A3000HV.
When a quick onceover is considered, the A3000HV is much larger, much heavier (just under 100 pounds) and far, dramatically even, more expensive at now just barely under $30,000. How will a less than $3,000, approximately 14-pound, portable in one hand amplifier ever hope to compete with a product arguably considered world-class? When I hooked up the speakers and subs, and connected the supplied ArgentPur PC12 15-amp power cord, I immediately liked the bass presentation. It was tight and, frankly, I felt was in every way dynamically equal to the T+A. Bass guitars had a nice pop as the strings were plucked, and an almost lifelike resonance could be heard. The highs were another matter. Most likely a function of the pure silver power cord, the highs were brighter than I prefer. Once done, the highs became spectacular. I listened to many of my go-to favorites for an entire afternoon. Soon enough, however, I began to notice some other differences.
Most prominently, there was a vast difference in the amplitude, given the same volume setting on my preamp. I expected this, given that the T+A A3000HV is rated at 500 WPC minimum continuous output at four ohms. The ArgentPur is rated at 200 WPC at four ohms. I was able to level-match the output by simply turning up the volume on the preamp. The next most obvious difference were the overall dynamics. The T+A had superior punch, weight, and an overall feeling of power across all three frequency ranges. The ArgentPur IBIS, while admittedly reasonably dynamic, could not deliver a similar performance. I also noticed a sense of completeness, with the lower octaves sounding noticeably more filled-in with the T+A, almost as if I was listening to live music. The ArgentPur was very clear, very precise, and sounded very impressive. It just lacked the full-bodied presentation provided by the T+A amp. Lastly was the imaging. Once again, the T+A was superior, delivering a wall of sound with width and depth. The image presentation spread across the entire room with pinpoint precision. The ArgentPur had fantastic imaging, but it was just less room-filling and precise.
I must admit, I am not surprised by these differences. And I still feel this is quite possibly an unfair (but fun to do) comparison. What I will say is this: I was very highly impressed by the performance of this $2,975 ArgentPur IBIS amplifier as compared to one costing just over 10 times as much. And for someone who is in no way interested in spending what I did for an amplifier or, for that matter, an entire audio system, the ArgentPur IBIS was a standout performer.
Final Thoughts on the ArgentPur IBIS Stereo Amplifier
How likely it is that the GaN technology will replace more traditional amplification methods is mere speculation at this point. How, and to what degree, this technology continues to improve will be the telling factor. I would also imagine there is a serious effort to improve the overall performance of GaN, and possibly incorporate it into other components. As for the here and now, GaN as an amplifier technology is unique. What I found with the ArgentPur IBIS is a product which checks a lot of boxes. It delivers outstanding sonics – absolutely much better than I expected. It is affordable. It is not prohibitively heavy and is small enough to be incorporated into virtually any audio system. And when compared to a world-class amplifier, it performed far better than I would have ever imagined.
My suggestion, especially if you have a bias against Class-D amplifiers in general, is to audition an ArgentPur GaN IBIS amplifier, or even the bigger monoblock version. The overall sonic presentation belies the cost of entry. When partnered with a quality streaming preamp and a set of speakers, an amazing-sounding system may easily be the result. Best of all, one not costing as much as a small house. Gallium Nitride is an amazing technology. And the ArgentPur IBIS certainly changed my mind. This is technology that every audiophile, regardless of where they are in their journey, needs to experience. It is just that good, and the ArgentPur is the most well-dressed and well-put-together option on the market today.
