High Definition Studio Direct Box
- 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
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.
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.
Produce Like a Pro Tries out the HDI
Radial HDI - What Does it Sound Like?
Box of Tone - Radial HDI
HDI - High Definition Studio Direct Box
Vintage King - Going Direct In with the HDI
Sweetwater - HDI Demo
HDI - With Acoustic
HDI - With Bass
Tom Sigal and Radial HDI
"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."
"Here is a product that can provide a range from pristine cleanliness to a phat in-your-face thickness in a matter of seconds, especially once you’ve spent 10 minutes with the product and understand the simplicity — yet depth — of the controls. And this is the way that the HDI really shines — you can get the sound you want in a hurry, especially in live situations where every second counts."
"For a commercial recording studio or a high-end personal studio, the HDI would be a worthwhile investment. Its ability to capture rich-sounding electric-bass parts would improve the sonics of every track it is used on. Its versatility for other electric instruments will have you reaching for it regularly."
"The Radial HDI is a great instrument interface, and one that brings so much of value to the role of a studio DI box. It’s definitely well worth an audition if you’re looking for a great-sounding instrument interface!"
"Sonic transparency is a Radial hallmark. With ‘High Definition’ as part of its name, the HDI abides—it’s designed to be the cleanest Radial direct box to date, but this time around, thanks to its dual topology, the HDI also stands as being the most colorful direct box Radial has ever produced."
FOH - Big Time Rush, JellyRoll, Lizzo, 5 Seconds of Summer
"Having the HDI on my last tour was a game-changer, and now it's a non-negotiable part of my creative process. This amazing little box is a powerhouse for bass, and I'm eager to experiment with it on other instruments, such as acoustic guitar, in my upcoming projects."
"I exclusively use the Radial HDI both live and in the studio. Pure, clean and rock solid. I don’t play without it!"
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"
Pat Metheny, Sting, Bill Evans, Joan Osborne, Marianne Faithful
"Radial has done it again! The HDI surpasses all of my expectations for what I've been looking for in a Direct Box. It's so simple to go from ultra clean, with the enhanced Jensen transformer, to a warm and colored sound with everything in between. This is a serious tool for any musician's tool box."
Goo Goo Dolls
"Loving the HDI. The thing is built like a tank and sounds awesome. Love dialling in the saturation (color). Makes everything pretty juicy"
Producer, Composer | Madonna, Travis Scott, Kanye West and many others
"The Radial HDI makes my Fender Rhodes sing - it sounds really good. I recommend them to everyone who wants a serious quality DI."
Engineer/ Producer – Megadeth, Danzig, Children of Bodom
"It’s one of those boxes that when you need something to just sound better, use the HDI. Most tracking sessions, I’ll just keep it plugged in so if any point I need a sweetened DI quick, it’s my go to."
Guitarist, composer, producer / 5 Finger Death Punch
" I really love the HDI. It has the most sonic options of all the DI’s out there."
From the Blog
Radial’s HDI Becomes the Go-To Professional DI For World Class Artists
Since its introduction just over a year ago, the HDI, Radial Engineering’s flagship high-definition studio DI, has quickly become the go-to studio tool of choice for world-leading artists, engineers, and... Read More
The Radial HDI – A Modern Approach to Direct Box Design
This is an interview with Radial Engineering’s lead designer, W.C. “Hutch” Hutchison on his vision and design philosophy behind Radial’s unique new DI box, the HDI. Share a bit about... Read More