SPL Crimson

Rob Tavaglione enjoys the SPL Crimson, his first experience with a desktop interface.

Up until this review, I’ve never used a desktop interface or monitor controller, as I drive a console with rack-mounted converters/interfaces. Sure, I’ve watched my less-fortunate colleagues struggle with some pretty bad (and quite popular and cheap) devices that are inadequate for pro use in many ways – including their mic preamps, converters, headphone amps and general build quality. The SPL Crimson appears to solve these problems and offer enough flexibility to claim the top perch in this category.


Input section: two single-transistor discrete mic preamps (with phantom power, HPF, XLR inputs), two pairs of line inputs on 0.25in balanced TRS connections, two Hi-Z instrument inputs on 0.25in TS, a pair of RCAs and an eighth-inch stereo miniplug for -10dB consumer devices (with an automatic, bypassable gain boost to pro level), and a digital input via SPDIF.

Monitor section: a large unstepped control-room level control, two sets of control room outputs (set A on XLR, set B on quarter-inch TRS with “tweaker” trim controls), two headphone amps with 0.25in TRS outputs and high output, a balance control for blending between the analogue input section and the DAW returns.

DAW implementation: two pairs of DAW returns via one USB 2.0 input (not 3.0, but 2.0 for its faster and more stable drivers with 1ms of latency), a total of six simultaneous channels of conversion to/from DAW, 24-bit processing, sample rates up to 192kHz, and low-jitter fixed internal master clock. The Crimson will operate sans drivers (using Core Audio), but high sample rates and low latency requires SPL drivers.

In use

I started out using the Crimson as a stand-alone monitor controller and was immediately struck by its ‘feel’. The steel chassis, the large control room level pot, the trim and headphone level pots, the switches – they all had that firm and smooth operation that inspires long-term confidence. The rear-panel legend was printed twice, once upside down, for easy connecting from either viewpoint. Savvy ergonomics? My interest was piqued.

As I ran through the functions in my mix session, the Crimson did not disappoint. I summed to mono to check for phasing issues; monitor switching was convenient with a single button push between A and B; and I kept two sets of cans (for me and the client) always connected for quick comparison checks. I noticed that the control room level did not go all the way down to muting the hot +4 outputs of my D-A converter, but the manual explained that these pots offer about -80dB of attenuation, enough to silence most sources. I did notice that the control room level was not balanced and centred at lower levels; I’d prefer stepped attenuators for such very low-level balance checks.

I downloaded the Mac drivers from SPL’s website (they offer Windows drivers, too, for XP and Vista 7 and 8) and suffered a bad install. Once I reinstalled the drivers, I received stable and excellent operation from the Crimson as a front end/DAW companion. For a naked, no-bed voice over, the Crimson mic preamps did a fine job. I’d describe their voicing as neutral and flat as they lacked any significant color but were super quiet and distortion free, even with lots (up to 60dB) of gain. They are maybe not as euphonic as some out there, but wisely clean and non-obtrusive. The instrument inputs were quite similar; with passive basses, active basses, acoustic guitars and electric guitars I received ample gain, low noise, and neutral voicing (again, not as ‘pretty’ as my reference preamp, the Millennia-Media STT-1, but smartly flat and flexible) with plenty of headroom.

For overdubbing vocals and such, the Crimson again nailed the job. The blend control allows no-latency monitoring of the analogue input signal and acts as a convenient one-knob ‘more me’ control when the singer needs just a little more level over the music. The multiple sets of DAW returns are also quite useful for setting up separate monitor mixes or wet/dry balances.

For more complicated scenarios (two headphone mixes, the need for talkback, and checking reference mixes) the Crimson has a number of advanced routing flexibilities. These are basically achieved with the Artist mode which routes analogue inputs in realtime, monitoring of DAW returns 1/2 to producer via Phones 1, returns 1/2 or 3/4 routing out to Speaker B for a headphone amp and Phones 2. Talkback is achievable with a externally amplified mic into analogue source 1-left; upon hitting the ‘talk’ button, talkback routes to Phones 2 and Speakers B, while Speaker A is dimmed to prevent feedback.

With so many functions available for a number of the jacks and connections, I had to constantly re-patch to achieve different set-ups (eg, inserting plugs in 0.25in inputs 1/2 will override mic inputs 1/2, instrument inputs 3/4 override lines 3/4, etc). Nonetheless, there’s enough flexibility and utility here to satisfy the needs of all but a traditional pro facility – and that’s a lot more function than typical out of a desktop device.

I used the Crimson at 44.1 and 48kHz and it sounded even better at 96kHz (a bit more open, shiny’ and precise) with basses, vox, guitars, acoustic guitars, and percussion.

To my ears

In my opinion, the performance of the Crimson measures up to professional grade. Clean and neutral mic pres and converters as well as excellent sonic performance (high headroom, wide frequency response, ample bottom end, excellent imaging) from all the analogue inputs are highlights (surely due to the Crimson’s high internal 34 VDC operating voltage). Digital capabilities are up to par as well with excellent, stable’ and fast drivers, low latency and a lack of issues from sample rate conversions or external clocks.

Despite a few technical concerns, I am going to give the Crimson an unmitigated approval for the most basic reasons. For $699, buyers get a steel chassis and a set of strong components that I estimate will last four to five times longer than those plastic toys which populate the desktops of my studio students/interns and newbie clients.

The reviewer

Rob Tavaglione has owned and operated Catalyst Recording in Charlotte, North Carolina since 1995. Rob has also dabbled in nearly all forms of pro-audio work including mixing live and taped TV broadcasts (winning two regional Emmy Awards); mixing concert and club sound. He is a regular contributor to Pro Audio Review. www.prosoundnetwork.com