Audionet PAM G2 Phono Preamplifier
and EXP high-current linear power supply
BY Greg Weaver – Jan 12, 2021
If you are not familiar with the German audio powerhouse Audionet by now, I suspect you haven’t been paying attention to the trends in the hyper-audio segment of the market. After having had the pleasure of reviewing the Audionet PRE G2 linestage and MAX monoblocks for the abso!ute sound (HERE), I adopted them as my reference electronics. I have also had the pleasure of spending time with, and also reviewing for the abso!ute sound, their flagship Scientist Series of machines, the Stern linestage and Heisenberg Monoblock’s (HERE), and the Humboldt integrated amplifier (HERE).
Now, rather than repeating myself, those interested in Audionet’s history may find healthy doses of that material in my Stern/Heisenberg and PRE G2/MAX treatments, both linked above. Today, I’m happy to share with you the details of yet another brilliant star in the Audionet product stable, their superb PAM G2 phonostage ($10,100) powered by the high-current linear power supply, the EPX ($10,100).
Now, I’ve heard the PAM G2 powered by the EPX before, and on something like more than twenty occasions over the past half-dozen years. It has been the primary phono stage in play during nearly every visit I’ve made to the GTT Audio Showrooms in New Jersey and has been used with virtually every US KRONOS ‘table demonstration by GTT Audio I’ve attended, from RMAF to AXPONA.
But it was an off-hand comment from Audionet CCO, their Branding & Marketing director, Jan Geschke, that was the stimulus for this tale. It was during a discussion about another Audionet product when he asked me if I had considered reviewing the PAM G2, as he felt it was one of the strongest products in their lineup. When I mentioned the idea to GTT Audio’s Bill Parish, the US importer for Audionet, he gave it his thumbs-up, and packed up a well run-in set of machines, which were very shortly installed in my reference system here in the Midwest.
The PAM G2 is compact and remarkably Spartan-looking. Standing just two and three-quarter inches tall, by twelve and a quarter inches deep, by seventeen inches wide, it weighs just about fifteen and one-half pounds. The front has only the power indicator lamp at the extreme left bottom of the chassis, the input selector button to the extreme right. It also has a pair of blue indicator lamps, to identify whether Input 1 or Input 2 is selected, in the center, all positioned in line about one-third of the distance up from the bottom, between the stylized “Audionet” logo centered at the top, and the “PAM G2 MM/MC Phono Preamplifier” designation centered at the bottom.
Moving to the rear, we find extraordinarily little unused real estate. Starting from the left, there are two sets of single-ended inputs for each of the two inputs, with their respective ground terminals, followed by both a balanced and single-ended set of outputs. Next is the 7-pin DIN input for the EPX power supply umbilical cable, followed by two pairs of selector switches, one for each input, for gain (38, 48, 58, and 68 dB), resistive loading (100, 150, 470, 1 k, 23 k, 47 k, or 69 k Ohms), and capacitive loading (100, 200, 320, and 420 pF), concluding to the very right with a standard IEC socket for the AC main cable if you are not using the EPX. To be complete, there are two other options for external connections for the PAM G2, both the EPS G2 ($4050), or the Ampere ($11,200).
While the faultfinder in me wanted to be concerned about having all the loading functionality available only from the rear panel rather than more readily accessible from beneath some cleverly concealed panel on the faceplate, the pragmatist in me soon extinguished that concern. Since the only times you would typically want/need to adjust any of these controls would be with the installation of a new linestage (to perhaps match overall system gain), or a cartridge, to adjust its loading options, the choice to go with the tidy, austere faceplate just made sense.
Looking under the hood reveals that primary signal amplification is performed by a dual-mono construction transistor input stage using FET inputs. Because of the current management system employed, these FET inputs provide an almost unlimited input resistance.
Each channel uses two specially adjusted Audionet operational amplifiers which have been integrated directly into the input circuit topology. Each of these unique OpAmps is discretely constructed from eighty-six individual components, resulting in a 100 MHz throughput capability!
The secondary equalization and amplification stage also employs a dual-mono configured output stage, both of which employ yet another discrete Audionet operational amplifier integrated into the driver circuit. Their drivers integrate this class-A circuit with remarkably high standby current, helping to ensure extremely high accuracy, even if tasked by driving the longest of interconnects.
Input switching employs an elaborate concept, taking place between the first and second amplification stage using the amplified and stabilized signal, helping to mitigate any negative audio effects. Further, it automatically mutes its outputs during any switching, preventing the possibility of any disruptive noises, while a safety switch monitors the supply voltage and shuts down the output signal quickly before any unwanted interference might reach the loudspeaker.
The EPX is nearly twice the size of the PAM G2, standing four and one-quarter inches tall, fourteen and a quarter inches deep, and seventeen inches wide, and it tips the scale at just shy of forty pounds. Because the best performance from the active circuits of the PAM G2 is highly dependent on the purity and stability of its supply voltages, the EPX provides extremely precise and load-independent power, effectively decoupling any harmful AC influences. Its constant, consistent, and low-noise source of current for the PAM G2 is very much like that one would expect to find used to power scientific tools and instruments in laboratory environments.
Okay, so how does it sound? Don’t let its diminutive stature lull you into underestimating what gifts the PAM G2 has to offer! Spoiler alert: from the word go this little beastie was clearly not taking any prisoners.
The first attribute to present itself after substituting the PAM G2 for my reference phono stage, with almost visceral assertion, was an inclusive advance in bass performance. Now, it wasn’t like I have ever felt slighted in this region before the PAM G2s arrival, but bass, and I mean down in the mid-teens (my Von Schweikert Audio ULTRA 9s offer a bandwidth of 16Hz to 40kHz), had newfound reach, authority, and scale, while revealing a more effortless sense of both definition and speed. The resultant advances in pitch definition, from orchestral use of double bass pizzicato to blues, jazz, or rock use of bass guitar strafes, yielded more clearly delineated tone, faster attack, and more convincing and demarcated decay.
While listening to cello works, like Janos Starker’s vivid interpretation of Bach’s Suites for Unaccompanied Cello [Speakers Corner reissue, Mercury Living Presence SR3-9016], or Camille Saint-Saëns’ Symphony No. 3 In C Minor, Op. 78, with Marcel Dupré on Detroit’s Ford Auditorium organ, and the Detroit Symphony Orchestra under the direction of Paul Paray [Mercury Living Presence SR-90012], textures, tonalities, and weight are presented in a most articulate and recognizable fashion, more revealing of both the flavor of the wooden body of Starker’s instrument, and of the compression, the visceral room pressurization, that the “Allegro Moderato” in the Saint-Saëns’ Organ Symphony can unleash.
Further, with well-recorded rock LPs like the 2015 Anthem release of Rush’s 1981 masterpiece, Moving Pictures, textures, tonalities, and weight are presented in a most revelatory fashion, revealing Geddy Lee’s fanatically precise and clean fingering.
Midrange is portrayed with both an unmistakable authenticity of tone color and its resultant palpability of texture. The only other phono stage I’ve had here that can rival or best it, was the internalized phono stage of the $150,000 Valve Amplification Company’s Statement 450i iQ integrated amplifier (review HERE), which encompasses the essence of their astonishing $80,000, two-box Statement Phono Stage.
Though I’m hesitant to liken their midrange performance to that of truly exceptional valve designs, the PAM G2’s midrange is so blustering with life, rich in detail, and full of harmonic bloom and body, that it almost begs such comparison. Fundamentals from piano, violin, guitar, human voice, et. al., are rendered so realistically, rife with texture and dimension, that they are presented with an immersive essence of “live-ness.” Their accomplishments here set a standard in this price class, as it delivers some of the most fluid, relaxed, smooth, and expressive midrange I have had the pleasure of hearing, particularly from a solid-state device.
This Audionet combo’s ability to reconstruct and integrate the upper-most octaves is simply exceptional. My reference Von Schweikert ULTRA 9s use a world-class beryllium dome tweeter and a pair of 5-inch, hybrid aluminum ribbon super-tweeters, one front-facing, with a second one, rear-facing, for ambiance retrieval. With such capabilities, the PAM G2/EPX synergy effortlessly exposed the detail, specificity, and ethereal air of the sounds of ride cymbals from jazz or blues groups, or triangles on classical recordings. With them in play you are treated to treble with clear, uncongested detail, vivid attack, authentic texture, and clear ambient decay, recording permitting. They are more than merely capable of delivering that sense of graceful effortlessness, of unfettered extension, and the perception of the air “of,” and around, the instruments that allow them to regenerate the final measure of trailing ambiance and decay that only the finest phonostages can deliver.
Let’s talk about its dynamic expressiveness, shall we? Shut the front door! From intimately exposing the subtitles of shading and articulation down near the noise floor, to recreating the impact and slam of a tympani or kick drum, to presenting the lifelike and visceral scaling of a full orchestral crescendo, this combo performs at the top of the class. In terms of macrodynamic jump, scaling down to its ability to unlock microdynamic eloquence and nuance, you likely aren’t going to find significantly better performance at any price.
Staging and imaging are crucial to any vinyl playback system and are areas where even adequate vinyl transcription crucifies digital playback. Once again, this Audionet two-piece phono preamplification system is guilty of proficiently outperforming its competition.
Listening to the opening of Rush’s “Witch Hunt,” again from the 2015 Anthem Moving Pictures release, lots, and I do mean LOTS of subtle and understated sounds are occurring, throughout the entire stage. All the while, no instrument is slighted, no sound misplaced, and nothing wanders or is in any way sullied. This complex recording includes two subtle percussion runs, one starting at 2:04, and another following at 2:12. They have always fascinated me, as I have never been able to successfully identify exactly what instrument is responsible for them. Yet they are succinctly recreated, centered, and emerge from about three feet off the floor. Further, the opening tom roll was simply breathtaking, revealing not only side-to-side positioning, but front-to-back queues as well, all the while exhibiting crisp, tight, pitch-defined skin tone and stick strikes. Very impressive!
Whether it be the fixed, delicate, and precisely revealed location of the faintly struck triangle buried deeply into stage right/house left in Steely Dan’s “Aja,” the title cut from the LP of the same album [Cisco Music CLP-1006], the uniqueness and specificity of the scattered children’s voices from the opening of “School,” from Supertramp’s Crime of the Century [Mobile Fidelity UHQR- 1-005], or the individuality and corporeality provided the four voices, and blues harps, so genuinely conveyed and individualized across the stage on “Down Home Blues,” from the 1990 Alligator release Harp Attack! [Alligator Records AL-4790], I have only heard a handful of phonostages that can come close to, let alone equal this combo’s capabilities in this regard. DAMN, what amazing performance.
I believe, especially in light of its combined exceptional microdynamic prowess, precision of imaging, lifelike sizing and voicing of staging information, that we as listeners are able to reap such generous benefits primarily because of the exceptionally silent backdrop afforded by the contributions of the superb EPX high-current linear power supply. Only the absolute best phono amplifiers I’ve experienced can both “reach” down into, and “play,” that manifest blackness. This Audionet pairing, like only a handful of much more costly entrants, pushes that limit in my experience.
There is no question that my expectations from the vinyl playback experience were shattered after hearing the staggering advances in performance that John Curl’s Vendetta Research SCP-2 phono stage, first introduced in 1988, delivered. That four-box solid-state phono stage set the standard for me; one that was extremely hard to compete with for the next decade. This Audionet combo may just deliver a similar experience to your listening!
Overall, the Audionet PAM G2, powered by the EXP, allows listeners to experience the delicate and ethereal characteristics captured on the very best recordings when played back using today’s absolute finest available LP transcription systems. And while one might be tempted to believe that buyers would have every right to expect the superb level of performance I have described as created by these remarkable Audionet machines from any phonostage selling in this price class, that, sadly, cannot be taken for granted. And as exceptional as this Audionet pairing is in general, where this combo really steps up and seriously overachieves, and I mean, comparable to and/or besting other phonostages in the forty-five to fifty-thousand-dollar price range, are with its abilities to regenerate authentic bass, its spatial acuity, and its overall authentic tone, texture, and body.
The Audionet PAM G2, with its splendid EPX external power supply, has jumped to the top of my list of what components to acquire next. Just in case you weren’t able to read between the lines here, what this superb combination of devices delivers, compared to its asking price, represent one of the most cost-effective values in phono preamplification available! I would suggest that if you aren’t willing to pony up the dough for this killer combo, that you shouldn’t give them a listen. The withdrawal you will suffer when they leave is considerable. Most highly recommended!
Audionet PAM G2 phonostage:
Frequency response: 0-2,000,000 Hz (-3 dB), DC-coupled
2-2,000,000 Hz (-3 dB), AC-coupled
signal-to-noise ratio: > 120dB
THD + N: < -102 dB for 20 kHz (df: 0-80 kHz) < -114 dB for 1 kHz (df: 0-20 kHz)
Output Impedance: 22 ohms
Output current: 60mA max
Power Consumption: max 50w
Mains connection: 230V, 50…60Hz.
Dimensions: 16.9 inches (430 mm) by 5.5 inches (140 mm) by 16.5 inches (420mm)
Weight: 33 pounds (15 kg)
Audionet EXP high-current linear power supply:
Voltage: ± 24V
Control accuracy between channels: >0.01% temperature compensated
Electricity: ± 3A
Mains connection: 110/220 … 240 volts / 50 … 60 Hz
Power Consumption: <1W standby, max 400W
Dimensions: 16.9 inches (430 mm) by 4.3 inches (110 mm) by 14.2 inches (360 mm)
Weight: 39.7 pounds (18 kg)
Manufacturer’s Website: https://www.audionet.de/
US Authorized Distributor:
Phone Number: 908.850.3092