The Radial ProDI Passive Direct Box is a no-nonsense, professional-grade solution for capturing clean, natural instrument signals in the studio or on stage.
Built with Radial’s legendary attention to durability and audio integrity, the ProDI delivers dependable performance and excellent sound quality at a price point that makes it a staple for working engineers, live sound professionals, and touring musicians alike. The Radial ProDI is a passive direct box designed to handle a wide range of high-impedance instruments including electric bass, acoustic guitar, keyboards, and electronic instruments. At the heart of the ProDI is a custom-wound Radial transformer that provides excellent signal isolation while maintaining clarity, punch, and phase coherence—ensuring your instrument translates accurately through a PA system or recording chain. A recessed ground lift switch helps eliminate hum and buzz caused by ground loops, while the rugged 14-gauge steel chassis protects the internal components from the rigors of stage and studio use. With its simple, reliable design and road-ready construction, the ProDI is an ideal choice for anyone who needs consistent, professional direct sound without complication.
Radial ProDI Passive Direct Box Features
- Compact passive direct box for stage and studio
- Able to handle huge transients without distortion
- Transformer isolation eliminates noisy ground loops
- Plug and play easy to use feature set - on stage or in the studio
- Great sounding, rugged passive DI
- High performance custom-wound transformer
- -15dB PAD for wide range of input levels
- Ground lift switch eliminates ground loop hum
- Ultra-tough design, to last a lifetime
- Completely passive, no power needed
Radial ProDI Passive Direct Box Applications
- ProDI for acoustic guitars and bass guitars
- ProD2 for stereo keyboards and drum machines
- Interface consumer audio with pro gear
- Eliminates buzz and hum caused by ground loops
Radial ProDI Passive Direct Box Specifications
- Technical Specs:
- Audio Circuit Type: Passive, transformer based
- Number of Channels: Single channel (mono)
- Frequency Response: 20Hz ~ 18.5KHz (± 0.2dB)
- Dynamic Range: 128dB
- Maximum Input: +18dB @ 20Hz
- Total Harmonic Distortion: 0.01% from 20Hz~20kHz @-10dB
- Phase Deviation: 1° @ 100Hz; 8° @ 20Hz
- Input Impedance: 140k Ohms, unbalanced
- Output Impedance: 150 Ohms, balanced
- Features:
- Transformer: Eclipse ET-DB2, 12:1 ratio
- Shield: Faraday, MuMETAL® can
- Input Pad: -15dB
- Ground Lift: Disconnects pin-1 at XLR output
- XLR Configuration: AES standard (pin-2 hot)
- Connectors: 1/4" in & thru, XLR-M out
- General:
- Construction: 14 gauge steel chassis & outer shell
- Finish: Durable powder coat
- Size: (W x H x D) 70 x 108 x 44mm (2.75 x 4.25 x 1.75")
- Weight: .54kg (1.2lbs)
- Shipping Size: (W x H x D) 102 x 76 x 165mm (4.00" x 3.00" x 6.50")
- Shipping Weight: 0.61 kg (1.35 lbs)
- Power: Passive, no power required
- Conditions: For use in dry locations only between 5°C and 40°C
Radial ProDI Passive Direct Box Includes
- Radial ProDI Passive Direct Box
- User Guide
- Manufacturer Warranty
3 Reviews Hide Reviews Show Reviews
-
very good conexion
Feb 18th 2026You can never go wrong with a ProDI. I have used many direct boxes over the years, but this one is the most reliable. It is perfect for bass guitar and acoustic instruments, providing a clean signal every single time.
-
Radial ProDI direct box
May 6th 2011The Radial ProDI has a great full range and is very clean. We are using it for live sound on bass and acoustic guitars with only a tuner/bybass pedal. Sound from both instruments are full and clear.
-
Rock solid!
Jun 28th 2010Clean and solid performer. No special features, but nothing to break, either! Used it on stage and in the studio without a hiccough. Built like a tank (kinda looks like one, too). The XLR connection is a little tight on my particular unit, but it's not a bad thing, especially for on-stage use! I've even used it as a poor-man's Reamp using a 1/4"-XLRF cable; no attenuation, so you've got to turn your output way down and/or go into a stepped-down amp input, but it worked fine.
Write a Review
Sign Up for exclusive sales and offers!