Products Artists Blog Company HDI Introduction Features Specifications FAQ BUY NOW HDI High Definition Studio DI BUY NOW High Definition Studio Direct Box The HDI is a studio-quality direct box designed to create exceptional recordings with any instrument, utilizing premium Jensen transformers and a unique Color control that provides an entirely new yet familiar-sounding sonic palette to experiment with. USER GUIDE Photos Dial in an amazing tone within seconds Blend from ultra-clean to amp-like distortion Smooth Opto compressor for peak reduction Mic and line-level outputs Oversized custom-wound Jensen transformer + More Features Instant Gratification Despite the complex circuitry housed within the unit, the HDI has an elegant set of controls that allows the musician or engineer to dial up a record-ready sound with a minimal amount of tweaking required. The Level control drives the inputs of the HDI with instant visual feedback from the responsive front panel meter, while the Color knob provides seamless blending between an ultra-clean tone and amp-style distortion and saturation, so you can add just the right amount of character and grit to your instrument. A smooth Opto compressor can be engaged to control the peaks of the input signal, and a High-Pass Filter clears up any excessive low frequencies added by the Color control. Lastly, a Presence control accentuates the highs and high-mids, providing the ability to cut through the mix with results that are sure to impress. Looks and Personality With its gunmetal anodized 1/4" thick milled front panel and distinctive styling reminiscent of classic outboard studio equipment, the HDI is sure to turn heads in any recording space. A custom output meter provides a level check at a glance, with oversized chrome knobs for precise adjustments and easy tweaking on-the-fly. The HDI is a stunning standalone unit, but it also comes complete with mounting hardware to install in standard 19" equipment racks. One or two HDI's can be installed side-by-side in a 2RU rack space, and like all Radial products, they are built with rugged components and designed to easily withstand the rigors of concert touring. Behind the Design While the HDI is incredibly easy to use - requiring only a few seconds to achieve great-sounding results - both the design philosophy and the under-the-hood processes at work are anything but simple. Click here to read an interview with the HDI's designer, W.C. "Hutch" Hutchison for an in-depth look at how the HDI came to be and what makes its circuitry so unique. + Hear from Hutch HDI Applications Using the HDI alongside an amplifier Record bass directly from the HDI while also feeding the unbuffered Thru output to a mic'd up amplifier to blend the two signals together. The HDI sounds so good on its own you just might mute the amp track altogether. Using the HDI on acoustic guitar The HDI pairs well with any instrument - with acoustic guitar it can add additional body and character that other direct boxes may lack. Take the line-level XLR output directly to your recording interface to bypass the need for any additional preamps in the signal path. Using the HDI Processed Output The HDI can be simultaneously used as a DI and as an instrument preamp, providing additional gain, saturation, and distortion before feeding the affected signal through to a clean amp or an amp modeling system. Using the HDI with modular synthesizers A dedicated Synth Input has a lower sensitivity to accommodate the hot outputs of modular synths or even other studio outboard equipment, allowing you to use the HDI to process any instruments or tracks you can think of. Videos HDI - High Definition Studio Direct Box Vintage King - Going Direct In with the HDI Produce Like a Pro Tries out the HDI Sweetwater - HDI Demo HDI - With Acoustic HDI - With Bass Tom Sigal and Radial HDI Reviews "It’s clear that the HDI is an extremely high-quality product, one that has been seeing near daily use in a studio that already has numerous DIs – not to mention preamps with 1/4-inch inputs – due to its high fidelity, ability to add nice harmonic distortion, and overall ease of use." By Eli Crews Read full review Artists Tony Levin Peter Gabriel, King Crimson, Mark Knopfler, John Lennon, Paul Simon "I’ve already used the new HDI on my bass for a number of recordings, with great results. It’s super clean, and has some dial in options that are wonderful to have on hand. Another home run for Radial" HDI Resources Part no: R800 2025 00 Owners Manual Smart Sheet Photos Rackmount Instructions Interview with HDI designer 'Hutch' Company Contact Careers History Artist Relations Client List Support Technical Support Product Questions Radial Warranty Quick Links DI Basics DI Questions Radial Family Primacoustic Jensen Transformers Stay in Touch SUBMIT Privacy Policy © 2021 Radial Engineering. All Rights Reserved.