Soulution 330 Integrated Amplifier

Balancing Act

Equipment report
Integrated amplifiers
Soulution 330
Soulution 330 Integrated Amplifier

The 330 in Action
To get the 330 integrated up and running, basic setup is straightforward; default settings on the very low side are in place for volume, phono impedance, etc. As with Soulution’s other celebrated products, the 330 is no slouch when it comes to a comprehensive, even mind-boggling array of features and functions that ought to satisfy even the tweakiest of audiophiles. But these are options on offer, so you only need dial in those that please you—or that your system may require. Since the menu is so extensive (and I have a word count to adhere to), I’ll highlight just a few items. 

The front-panel push-button control knob’s capabilities far exceed its humble “volume” designation. Sure, controlling level is its primary job, but think of a butler who’s also a chauffeur, a cook, an event planner, and a mechanic, and you’ll get the idea. More akin to a master controller, its other duties include (but are not limited to) input selection—hold the button down for a moment until three LEDs light up and you can scroll through the input options (1 through 4 plus phono), then push the knob again to select the desired input. A press of the “prog” button initiates “program mode,” where turning the knob allows scrolling through myriad program functions. To select one, push the knob again. Once within a given program function, you can scroll through its values and make a selection by, guess what, pushing the knob. To exit, simply press the “prog” button again. The hierarchy is logical and pretty easy to master once you get the hang of it. Program function selections include defining values for start-up defaults (volume, inputs, etc.), multi-amp and/or surround setups, display brightness, remote control ID, phono options, polarity, firmware (which can be updated via the 330’s Link-Com USB input), among others. Apart from switching between inputs (obviously) and assigning a couple of volume defaults, I mostly just made adjustments to impedance within the phono section, trying out different values for the two turntables and cartridges deployed during my audition. Another noteworthy feature is the RIAA-IEC high-pass filter you can activiate “on the fly” during playback.

A confession: I used the remote control far less than I expected. It’s commendable for its extraordinarily sophisticated in-depth capabilities and its ability to let you access virtually all control functions from your listening seat, but I never quite got used to its buttons’ first-order functions. It certainly worked well and had a logical system (clearly explained in the user manual) and path to menus, settings programming, and so on, but personally I didn’t find it to be especially intuitive beyond the basics. More importantly, I genuinely did enjoy that main front-panel push-button control knob’s immediacy, ergonomic feel, subtle clicks, and the versatility of functions that could be accessed from a single point of direct contact. Also this way I never needed to concern myself with a direct “sight line” from remote to amp.

Because my review sample came equipped with the phono-board option, I explored that first and foremost (primarily with Clearaudio’s Performance DC Wood turntable, Tracer tonearm, and Stradivari V2 cartridge, but also with Acoustic Signature’s Double X turntable, TA-2000 tonearm, and Air Tight PC-7 mc cartridge). As noted the review sample did not include the DAC option, so my other listening was digital streaming (mostly Tidal via Roon on my MacBook Air) and CDs via an MBL Noble Line N31 CD player/DAC. 

When I first fired up the Soulution 330 for several days of ongoing break-in (before I started critical listening), I noticed the output volume seemed quite low and the default volume setting was only 10 within a range of up to 90. At first I hesitated to increase SPLs, but crank it up I did, finding levels between 50 and 70 suitable for most source material. I was also a bit nervous about how the MBL speakers, which are designed to pair with MBL’s own electronics, such as the N51 integrated, would take to the Soulution integrated’s power. They fared beautifully—the Soulution’s signature dimensionality, detail, and smooth, continuous power with grip and headroom to spare complemented the Radialstrahlers’ unique omnidirectional dispersion, substance, and spaciousness. I’m speaking primarily of LP listening here, but I don’t believe I’ve ever heard Red Book CDs sound as thrilling in my home as they did through this setup—and not only those of great recordings. I’d recently picked up an original 2-LP pressing of Tuscon-based Calexico’s Feast of Wire [Quarterstick QS 78] and for fun I pulled out the Canadian-made CD on the same label. Turns out the disc was impossible to play as mere background music. The vinyl version was swell too, but this was the CD. Its off-kilter desert-noir charms—fully rendered Tex-Mex accordion bellows; the sharp, brassy blasts of mariachi horns; crisp, clean guitar picking; and Joey Burns’ natural, often-understated vocals—kept tearing my attention away from my computer work at my faraway desk by evoking sonic scenes of tumbleweeds and border towns. As with LP playback, backgrounds were as astonishingly dark and quiet as a moonless desert night.

For vinyl listening through the 330, I experimented with increasing and decreasing the phono impedance—the default setting is 100 ohms—with varying results (much depended on the recording, too, of course). Generally, I preferred lower impedances; higher values seemed to bring more sonic weight and density but also skewed slightly less lively and realistic due to a reduced sense of air and overall openness. Staging also felt a bit more closed in at times. However, such gradations were relatively subtle unless more drastic adjustments were applied. For the 0.6mV mc cartridges in use I settled on values of from 200 (240 most often) to 400 ohms, tending to prefer higher values for rock ’n’ roll and other harder-hitting material. Lackluster recordings were rendered pretty faithfully without much added sweetening, yet still seemed to be sonically spit-shined, rendered with body and energy. The 330 is not dead neutral and if you’re seeking X-ray transparency this might not be the ideal amp for you. That said, it brings plenty of solidity and power-range oomph, preventing music from sounding thin or threadbare but more textural, dimensional, and substantial. 

Singers’ voices displayed a certain purity and realism, which meant that tiny details and nuances in performances stood out more. A listen to “Don’t Wait Too Long” on Mobile Fidelity’s delightful LP reissue of Madeleine Peyroux’s Careless Love highlighted her subtle, sassy vibrato stylings that can be easy to miss on less resolved systems, alongside peppy Hammond B3 accents and silky-smooth snare and cymbal brushstrokes—so fine, so delicate, so real. On “Dance Me to the End of Love” pitch accuracy on vocals, upright bass, and piano, a notoriously challenging instrument to reproduce, also seemed spot-on, as did the musicians’ placement. All made for a beautiful, well-balanced, airy, and oh-so-natural presentation.