SBS Designs S2-PRO Stereo Amplifier




syn·er·gy /ˈsinərjē/


The random and and unexpected moment when three reviewed components combine to produce an exhilarating and unforgettable result. “Bybee iQSE ll OEM’s + Dynamique Audio Tempest 2 cables + SBS Designs S2-PRO amplifier = Wow!”

Gregvoth.jpgCase in point, I present an amplifier that has been available as a pro audio component since its introduction in 2014, designed for use in recording studios as well as home hifi use.The SBS S2-PRO is as captivating a power amp as it is an ugly duckling.

The SBS Designs S2-PRO Class AB power amplifier, hand-built in the USA, delivers 125 watts per channel, designed to resemble a bit of a 1960s relic – it’s plain grey rack-mount face (with no handles front or rear) is described as “a bold new look”decorated with a chunky toggle switch and red power light as from a guitar amplifier, three pairs of colored lights for Max Out, Active and Ready scenarios and a more than generous smattering of (in this graphic designer’s experience) a nausea-inducing script font, more akin to the red and white water decals I slid onto model planes and cars in my youth than the “audio jewelry” designs audiophiles most often see. 




A cooling fan is mounted on the left side of its chassis and vent holes perforate areas of this amps top and right side.The amp’s all-metal knobs are meant for road abuse and apparently designed for insertion into a rack. Its rear face is equipped with two pairs of banana style speaker jacks (no 5-way binding posts), a pair of XLR inputs, two adjustable gain knobs, fuse access and an IEC jack for a power cord, with roughly half the rear face covered with a heat sink the depth of my power cable’s IEC plug. Not much to look at, but oh boy, does it sing!

When Clement brought this amplifier to my attention, asking for a few sonic impressions (and maybe a review), frankly, I didn’t expect much due to the amplifier’s rather odd appearance. He assured that the SBS S2 Pro’s designer Craig Bernabeu aka “Shorty” has a hard-earned reputation in the pro audio community for delivering great sound as we sat the SBS S2 PRO between the Tekton Double Impact’s and connected it into my main rig.

psaudiobox.jpgI can honestly say we both sat stunned. I was particularly confused, likening the amp’s immediate impact as “brighter” – what I would later understand as faster and more immediate in response. As my initial shock wore off as a few songs played, I better understood the amp’s virtues – it’s fast, accurate and very responsive, producing a greater background blackness and musicality that renders the source with noticeable musicality and, what feels like, increased resolution.

I was amazed how Jack Bybee’s iQSE ll OEM’s transformed my Tekton Double Impacts and am elated with the use of Dynamique Audio’s Tempest 2 cables in my system. However, it’s the addition of the SBS Designs S2-PRO stereo amplifier that seriously catapulted my rig to unimagined heights of aural bliss. The DI’s possessed far more of the shimmer and speed produced by my former Eminent Tech LFT-8b’s hybrid ribbons. Further, DI’s possessed a liveliness, musicality and PRAT (pace, rhythm and timing) not anticipated nor experienced with any amplifier I have ever had in my rig when reviewing. I’ve seriously enjoyed quite a few other brands, but never had a more musical experience.



Origin250.jpgIn an all-too-brief 3-way phone conversation, with CP and I in the car and Craig “Shorty” Bernabeu (photo above) over the phone, only minutes after our initial listening session – Shorty told us “…this is a true Class AB design with a zero negative feedback loop.” From what I’ve read, the absence of feedback in an amplifier’s design can result in increased background noise –thankfully this is not the case with the SBS S2-PRO. Its output is sure-footed, musical and alive, fast and dynamic, nuanced and all together captivating. Quoting from its 2014 introductory fact sheet, the S2-PRO Class AB stereo amplifier, with its true Class AB drive sections, “combines a rich feature set, superb specs, road-tested reliability and an affordable price point to make it the ideal choice for recording and mastering studios, live sound venues, professional mobile sound systems–even home hi-fi.


nubaya.jpgThere is a rumble in this jungle! “Lost Kingdoms” from Nubya Garcia’s “Nubya’s 5ive” (Jazz re:freshed 2018) was stunningly dynamic and intense and in-the-room, as they say. This amplifier and combination of other components offers a s musicality that’s intoxicating! There’s a growl to the rhythm section and drive that’s energetic and addictive, on a stage with good depth and width. The bass output  and drive of the Tekton DI’s has increased dramatically – the addition of both the Bybee iQSE OEM’s and Dynamique Audio cables, along with the SBS Designs S2-PRO power amp have worked witchcraft here, adding a denser body and presence and immediacy to delivery previously not experienced.

adammusic.jpgAdam Baldych and the Baltic Gang’s “Million Miles Away,” from their album “Imaginary Room” (Act 2012), is a simple, textural piece. As it drifted along with more band menders contributing in “Zarathustra,” the textural palette grew in expressiveness, size and dynamic contrast. The S2-PRO amplifier emerged this listener in the midst of this yearning and meandering musical journey. As by listening session progressed from track to track, I was taken with its quiet power and resolve. It’s not about brute force, though it has that ability to command such attention, it’s about subtlety and surety and presenting the illusion of this wonderful musical experience happening right in your own room and there any passion exerted in performance exudes from the speakers without effort as each note commanding one’s attention. The SBS S2-PRO posses a firm grip on the musical content, as it confidently exudes its musicality; it’s less about sheer muscularity and more akin to just being well-toned and agile. It’s not a show boat (nor does it bloat), the S2-PRO doesn’t over-scaling instrumentation nor hit you over the head with aggressive over-reaching dynamics… it lays back and unfolds the source material as it entices one to listen… and linger longer.

jeffgoldblum.jpgFor fun, I put on Jeff Goldblum‘s latest “I Shouldn’t Be Telling You This” (Decca 2019). The first track, “Let’s Face The Music And Dance,” with Sharon Van Etten, is my favorite track of the first three on this new release – the piano tone is big and bold, with great bounce and a  nostalgic bent. The varied vocal talent on this effort were rendered large and presented with great body. The unison playing on “The Beat Goes On” was fun and lively with a great presence and sense of space. “Driftin’” presented a piano with great body in a wistful bouncy arrangement with great rhythm and a punchy horn accompaniment. The upright bass was three dimensional very “plucky,” also presented with great body and warmth. The Hammond B3-style organ added a wonderfully nostalgic and playful support. The Mildred Snitzer Orchestral is one well rehearsed band and it shows!

Continuing on. Curtis Fuller Quintette‘s “Blues-Ette” (Savoy Records 1959) a vinyl reissue that I stumbled upon one Record Store Day buried deep in the racks, is one I liked so much that I returned the following year to find more copies. Finding two, I bought for a friend, and handed the other off to a fellow traveler. This record feels like an old friend, it’s in the same vein of a lot of jazz from the late 50s, friendly and melodic, with nice drive, presented on a decent stage with solid imaging. Previous plays of this album prior to my rig’s new-found synergistic  improvements, have felt somewhat lackluster, lacking coherence and PRAT… but not here, in this moment, as experienced with the A2-PRO amplifier in the system. Resolution increased, focus sharpened and dynamic contrasts, both large and small, have great impact and noticeably added nuance.

Ricky Lee Jones rendition of “Been a On A Train,” from Billy Childs’ “Map To The Treasure: Reimagining Laura Nyro” (Masterworks 2014) is a track played often, yet I hardly recognized my rig as it played here — depth pushed farther back, strings sang more sweetly, with more resonance and added flourish. The front of the stage rolled back, yielding greater dimensionality with instruments carved sharply with crisp edges as if out of denser air. Quiet seemed quieter and dynamics had greater impact, verve and thrust – such realism and resolve bore little resemblance to the system’s prior configuration.



The Wrap

mw2019.jpgOur friend Dennis Parham, upon hearing of our first experience with the SBS Designs S2-PRO, promptly asked “What’s it look like?” “Admittedly, not much,” I responded. I’ve been told an audiophile-worthy model of this amplifier might be in the works. If produced in a standard width, with style and finish details that would appeal more broadly to the audiophile market, such a special edition would have few competitors at it’s rather modest price point and, if such a model could be scaled down successfully to around $1899, such a component might very well leave all comers in its wake. 

Beauty is in the ear of the beholder. The SBS Designs S2-PRO hits all the notes — it’s fast, with amazing PRAT, responsive, with a percussive power embedded in every sound produced… and it’s nuanced, delivering depth and and detail with  increased resolution. It’s what this amplifier gets right that makes it a must hear.

I’ve had the good fortune to have a fair number of amplifiers here in our loft in these reviewing years, and, as Clement pointed out that, in every case, this large room (32’ x 42’ x 13’) has controlled each and every amplifier, mitigating virtues and restricting capabilities. Granted, living in such a large space is not a common experience for many people — I can move things around to give any component the room it needs to breath and perform. I don’t have side or back wall issues, but larger spaces present challenges in themselves… often the sheer volume needed to displace limits and amplifier’s reproductive capacity.

Many of these amps  have sounded great and I’ve said so. In smaller, more controllable environs, they may preform spectacularly, exceeding what I’ve heard here. The SBS Designs S2-PRO is the first amplifier that has tamed this loft space, delivering far beyond the capabilities of amplifiers many times its price.

The synergy that presented itself with the overlapping of the past three reviewed products has resulted in a extraordinary jump in sound quality. Each product was noted as special and capable of elevating performance in most every rig, but few could have predicted the outcome of such a combination. It appears to be the sheer luck of the draw that has raised the level of reproduction here. While not a card player, I was dealt a winning hand. It’s a keeper.



greg voth       


SBS Designs S2-PRO Power Amplifier

Price: $3995US, €3,995.00


SBS Designs

SBS Designs offices are located in East Brunswick, NJ


125 watts @ 8 Ohms per channel

225 watts @ 4 Ohms per channel

Frequency Response from 10 HZ to 100 KHZ

Input Sensitivity 1.25

Slew Rate 100 v/us

THD .02%

Damping Factor 100

Class AB output, featuring true complementary class AB drive sections.

2RU Convection Cooled.

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