- PASSIVE DI
The Radial JDI is a warm sounding passive direct box that can transfer extreme signal levels without distortion while eliminating hum and buzz caused by ground loops.PRODI
The Radial ProDI is a high performance passive direct box that is ideally suited for bass and acoustic guitar to deliver a warm, distortion-free sound.Trim-Two
The Radial Trim-Two is a passive direct box, designed for use with laptop computers and other consumer type devices where the user has a requirement for a 'ready access' volume control for quick adjustments on stage.JDI Stereo
The Radial JDI Stereo is a passive stereo direct box designed to handle extreme signal levels without distortion of any kind.PROD2
The Radial ProD2 is a high performance stereo direct box designed to easily interface keyboards to the PA and recording system without noise.StageBug SB-2
The Radial SB-2 is a passive direct box designed for keyboards and active bass. Features stereo to mono mix function to save mixer channels.JDI Duplex
The Radial JDI Duplex is a stereo passive direct box that fully capable of handling any audio signal without distortion, artefact or noise.ProAV1 & PROAV2
The Radial ProAV is a passive direct box with stereo-to-mono merge function designed specifically for the audio-video integrator to reduce channel requirements.StageBug SB-5
The Radial StageBug SB-5 is a compact stereo direct box designed to accommodate laptop computers, tablets and other consumer audio products when amplifying the signal through a PA system.JD6
The Radial JD6 is a 6-channel rackmount direct box designed for keyboards in studio and live touring where optimal signal transfer is required without noise.ProD8
The Radial ProD8 is a high density 8-channel rackmount direct box optimized for professional keyboard rigs where optimizing signal transfer without noise is needed.StageBug SB5W
The Radial SB5-W is a passive stereo direct box designed to fit inside a standard electrical wall box and utilizing a Decora wall plate cover.
- ACTIVE DI
The Radial Firefly is a class-A direct box that combines a 12AX7 tube drive with transformer isolation to deliver spectacular warmth and character.J48
The Radial J48 is a 48 volt powered active direct box that delivers studio quality performance while eliminating hum and buzz caused by ground loops.JDX 48
The Radial JDX 48 is a guitar amp DI that captures the sound of the amplifier and speaker to deliver the tone of a 4x12 half-stack without the need of a microphone.USB-Pro
The Radial USB-Pro is a high-resolution DI box that converts sound files from a laptop and seamlessly transfers them to a pair of balanced audio outs.JDV MK5
The Radial JDV is a class-A direct box with a unique zero negative-feedback circuit that delivers unmatched signal purity for the most demanding recordings.J48 STEREO
The Radial J48 Stereo is a high performance active direct box with extra headroom and advanced grounding for professional touring and studio recording.PZ-DI
The Radial PZ-DI is a unique direct box that is specifically designed for acoustic and orchestral instruments.JPC
The Radial JPC is an active stereo DI with transformer isolated inputs to eliminate noise that is common with computers and consumer audio devices.Headload
The Headload is a combination load box and attenuator that is capable of handling up to 130 watts RMS of continuous power and peaks of 180 watts.PRO48
The Radial Pro48 is a high performance active direct box that is ideally suited for bass and acoustic guitars to deliver clarity without distortion or artifact.StageDirect
The Radial StageDirect is a state-of-the-art active direct box designed for musicians who require extra control when they are on stage.J33
The Radial J33 is a combination stereo phono preamp and direct box designed to interface turntables to professional audio systems.Headload Prodigy
The Headload Prodigy is a combination load box and DI that lets you perform or record at low volume with maximum tone.StageBug SB-1
The Radial SB-1 is an ultra-compact active direct box designed for acoustic guitar and bass that fits inside a guitar case!StageBug SB-4
The Radial StageBug SB-4 is a compact active direct box that has been optimized for use with piezo transducers.BT-Pro
BT-Pro™ is a Bluetooth® DI designed to capture the wireless transmission from a Bluetooth® device and convert the signal to a balanced line for use in a PA.JDX Direct-Drive
The Radial JDX Direct-Drive™ is a unique and powerful device that simulates the sound of a guitar amplifier.4-Play
The Radial 4-Play™ is a multi-channel direct box that has been specifically developed for multi-instrumentalists to enable them to quickly change instruments on stage.
The Radial X-Amp is a dual output class-A active Reamper that lets you take a pre-recorded track and send it through amps and pedals without noise.Reamp JCR
The Radial Reamp JCR is a high-performance passive Reamper that lets you take a pre-recorded track and send it through a guitar amp or pedal chain without noise.ProRMP
The Radial ProRMP is a passive Reamper that lets you take a pre-recorded track and send it through a guitar amp or pedal chain without noise.X-Amp 500 Series
The Radial X-Amp is a 500 series class-A active Reamper with isolated outputs that lets you send a pre-recorded track to two amps and re-record the new sound.Reamp KIT
The Reamp Kit combines a Radial J48 direct box for recording with a Radial X-Amp for Reamping amps & pedals to enhance the tone of your recorded tracks.SGI
The Radial SGI Studio Guitar Interface class-A line driver with load correction lets you send a guitar signal beyond 100 meters via balanced cable without noise.JD7
The Radial JD7 Injector is a class-A guitar distro/splitter with built-in Radial DI and Reamp that can drive up to seven amps or pedal chains simultaneously.JX44
The Radial JX44 Air Control is a wireless signal manager for concert stage that lets you remotely control 4 guitar inputs and 6 amp outputs at once.SGI-44
The Radial SGI-44 guitar interface is a balanced signal extender designed to send the signal from a wireless receiver to the pedalboard and back to the stage amp.
JS2 / JS3
The Radial JS2 and JS3 are high performance passive microphone splitters that lets you feed mixing consoles without signal degradation or noise caused by ground loops.PRO-MS2
The Radial ProMS2 is a high performance mic splitter that accepts a balanced microphone signal and sends it to three outputs simultaneously. As a passive device, there is no need for power.OX8
The Radial OX8 is an 8-channel rack mounted microphone splitter that lets you feed two mixing consoles without signal degradation or noise caused by ground loops.LX8
The Radial LX8 is an 8-channel rack mounted line level splitter that lets you feed two audio systems without signal degradation or noise caused by ground loops.JD7
The Radial JD7 Injector is a class-A guitar distro/splitter with built-in Radial DI and Reamp that can drive up to seven amps or pedal chains simultaneously.JX44
The Radial JX44 Air Control is a wireless signal manager for concert stage that lets you remotely control 4 guitar inputs and 6 amp outputs at once.mPress
The Radial mPress is a modular press box that can be expanded as needed to feed a community-sized press gallery or distribute audio for an international event.Exo-Pod
The Radial Exo-Pod is a passive broadcast splitter that can take the balanced line output from a mixing console and distribute the signal to 14 hand-held recorders, video cameras or wireless receivers.Catapult
The Radial Catapult is a 4-channel audio snake that lets you send analog or AES digital audio signals over standard Cat 5 or Cat 6 shielded twisted pair cable.LX-2
The Radial LX-2™ is a passive balanced line level audio splitter that allows you to easily send an audio signal to two different destinations at once without noise.LX-3
The Radial LX-3™ is a high-performance balanced line-level splitter designed to send one audio signal to as many as three destinations at once.
The Radial Twin-Iso is a two channel balanced line-level isolator that eliminates the hum and buzz caused by ground loops that is often encountered in audio systems.J-ISO
The Radial J-ISO & Pro-Iso are full bandwidth stereo interfaces that converts +4dB balanced line level signals to an unbalanced consumer level output.Pro-ISO
The Radial J-ISO & Pro-Iso are full bandwidth stereo interfaces that converts +4dB balanced line level signals to an unbalanced consumer level output.J+4
The Radial J+4 is a -10dB to +4dB stereo preamp that lets you boost a low output unbalanced signal and interface it with a balanced professional audio system.JPC
The Radial JPC is an active stereo direct box with transformer isolated inputs to eliminate noise that is common with computers and consumer audio devices.McBoost
The Radial McBoost™ is a high performance microphone signal booster designed to elevate the output of a typical dynamic microphone for greater transient response.SGI
The Radial SGI Studio Guitar Interface class-A line driver with load correction lets you send a guitar signal beyond 100 meters via balanced cable without noise.SGI-44
The Radial SGI-44 guitar interface is a balanced signal extender designed to send the signal from a wireless receiver to the pedalboard and back to the stage amp.STAGEBUG SB-6
The Radial StageBug SB-6 is a high performance 2-channel passive audio isolator designed to accommodate both balanced and unbalanced signals.STAGEBUG SB-7
The Radial StageBug SB-7 Earmuff Headphone Silencer lets you turn off one side of your headphones to stop the bleed.STAGEBUG SB-15
The Radial Stage Bug SB-15 High Performance Signal Buffer lets you drive guitar pedals without added noise and also powers 15V Tonebone pedals.ICECUBE IC-1
The Radial IceCube IC-1 is a balanced line level isolator designed to quickly eliminate hum and buzz problems in an audio system by simply inserting it into the signal path.DECODER
Decoder is a microphone preamp and Mid/Side stereo matrix that allows the user to easily create M/S recordings without having to re-configure a recording consoleSpace Heater
The Radial Space Heater is a single space 8-channel tube overdrive that can be used as a stereo summing mixer or as multi-channel studio distortion.Twinline
The Radial Twinline is a unique device that enables a guitarist to share effects pedals between two amps when using the amplifiers' built-in (rear-panel) effects loops.MR5
The Radial MR5 is a MIDI signal translator that allows you to use a MIDI controller to drive the JX44, JX42 and other Radial products that use the JR5 footswitch.
Radial studio products simplify the work-flow without affecting the signal quality to ensure creativity is not hampered during production.MC3
The Radial MC3 monitor controller is a 'straight wire' passive switcher that lets you control two sets of monitors, sub woofer and feed two sets of headphones.Gold Digger
The Gold Digger is a 4-channel mic selector that enables the engineer to quickly compare the sound of four different microphones while sharing the same preamp.Cherry Picker
The Radial Cherry Picker is a unique tool that simplifies the process of selecting the best preamp for use with a given microphone.
Guitar / Amplifier
Whether switching guitars on stage or amps in the studio, Radial offers a complete range of switchers from simple ABYs all the way up!JD7
The Radial JD7 Injector is a class-A guitar distro/splitter with built-in Radial DI and Reamp that can drive up to seven amps or pedal chains simultaneously.JX-42
The JX-42 is a compact guitar selector that lets you instantly switch between four guitars and two amps on stage.JX62
The Radial JX62 is a guitar and amp switcher designed for both wired and wireless guitars in a live concert touring environment.jx44
The Radial JX44 Air Control is a wireless signal manager for concert stage that lets you remotely control 4 guitar inputs and 6 amp outputs at once.JR5
The JR5 is a remote footswitch that lets you select guitars, amps or effects when used with the JX44 and JX42.JR2
The JR2 is a dual function remote footswitch that lets you switch or mute outputs, depending on the Radial device that is connected.BIGSHOT ABY
The Radial BigShot ABY is a true-bypass ABY switcher that toggles or combines two guitar amplifiers in phase and without hum & buzz caused by ground loops.BigShot I/O
The Radial Bigshot I/O is a true-bypass instrument selector that lets you switch between two sources and balance the signal level between them.BigShot EFX
The Radial BigShot EFX is a true-bypass effects loop switcher that lets you turn on or off two pedal-chains and take them out of the signal path when not in use.BigShot SW2
The Radial BigShot SW2 is a dual output remote control with choice of latching or impulse settings to control two amplifiers or effects.Twinline
The Radial Twinline is a unique device that enables a guitarist to share effects pedals between two amps when using the amplifiers' built-in (rear-panel) effects loops.
Radial addresses the fast paced world of live touring with a range of switchers for backing tracks, wireless systems and mixers.Relay Xo
Radial Relay Xo is a 1-in, 2-out switcher for balanced audio used with mic or line level sources as talkback and communication router.SW4
The Radial SW4 is a four channel balanced audio switcher designed for wireless systems, mixing consoles and digital guitar processors.SW8
The Radial SW8 is a backing track switcher that automatically switches between two playback systems to prevent disaster during a live performance.HotShot DM-1
The Radial HotShot DM-1 is a combination mic mute and switch that enables the artist to communicate to band members and techs via momentary footswitch.HotShot ABi
The Radial HotShot AB1 is an XLR balanced input selector that can instantly toggle between two input sources to one output via a latching footswitch.HotShot ABo
The Radial HotShot ABo is an XLR balanced output selector that can instantly toggle one input between two output destinations via a latching footswitch.JR2
The JR2 is a dual function remote footswitch that lets you switch or mute outputs, depending on the Radial device that is connected.JR2-DT
The JR2-DT is a desk-top version of the JR2. It features two top-mounted activator switches to control AB and Mute functions.BigShot SW2
The Radial BigShot SW2 is a dual output remote control with choice of latching or impulse settings to control two amplifiers or effects.
The Radial Phazer is an analog phase alignment tool that lets you combine two sources and bring the fundamentals together for a more natural tone.Phazer Bank
The Radial Phazerbank is a 4-channel analogue phase adjustment tool that enables the engineer to effortlessly adjust the phase between two microphones when double mic'ing a single source.PhazeQ
The Radial PhaseQ is 500 series phase alignment tool that lets you combine two microphones and bring them into perfect phase for a more natural tone.EXTC-SA
The Radial EXTC-SA™ is a stand-alone audio interface that lets you incorporate guitar effects into the realm of pro-audio recording.EXTC
The Radial EXTC is a 500 series effects send & receive module that lets you incorporate guitar effects into the realm of pro-audio recording.Tank Driver
The Radial Tank Driver is a wonderfully unique 500 series module that allows you to drive a balanced line level signal through the reverb tank in your Fender Twin amp!Vocoloco
The Voco-Loco is a foot-controlled effects loop that enables the lead vocalist, sax or trumpet player to incorporate guitar effects pedals into the signal path, just like an electric guitarist adds effects for soloing.Trimode
The Trimode tube distortion takes you from slight overdrive to full-on distortion. Think Mesa-Boogie in a pedal and switch instantly from rhythm to lead.Vienna Chorus
The Vienna Chorus is vintage bucket-brigade chorus that delivers old-school analog tone. Dual-mode controls lets you switch from slow to fast choral effects like a Leslie.
- 500 SERIES
Choose between Radial's award-winning racks for ultimate control over your signal path. Compatible with all 500 series modules, Radial racks are equipped with extra features for greater connectivity plus resettble electronic fuses to keep your gear safe!Workhorse
The Radial Workhorse is an 8-slot 500 series power rack with a built-in analog summing mixer, headphone amp and extensive patching capabilities.WR8
The Radial WR-8 is an 8-slot power rack that lets you load up to eight 500 series modules. Can be expanded with the WM8 mixer for full Workhorse capabilities.Powerhouse
The Radial Powerhouse is a 10-slot power rack for 500 series modules designed to provide maximum density for professional studio setups.SIXPACK
The Radial SixPack is a desk-top 6-slot power rack for the popular 500 series, designed to create the ultimate channel strip with 1600 milliamps of available current.Cube
The Radial Cube is a desk-top 3-slot power rack for the popular 500 series, designed to create the ultimate channel strip with 500 milliamps of available current.PowerStrip
The Radial Powerstrip is a 3-slot power rack for the popular 500 series, designed to create the ultimate channel strip with 500 milliamps of available current.
Preamps & EQs
Radial gives you a choice between tube and solid state preamps to suit your most demanding recording needs. Compliment them with choice of induction coil or discrete class-A equalizers to add creative soul, sparkle or fat bottom end.POWERPRE
The Radial PowerPre is a 500 series 100% discrete mic preamp with Accustate input control for low noise and transformer coupled output for added warmth.JDV-PRE
The Radial JDV-Pre is a 500 series class-A instrument preamp with variable load for magnetic, piezo and active sources and high-pass filter to eliminate resonance.PowerTube
The Radial Powertube is 500 series 100% discrete class-A preamp with high voltage 12AX7 tube gain stage and transformer coupled input for vintage character.Premax
The Radial PreMax is a 500 series channel strip tha combines a state-of-the-art preamp with a 3-band EQ for easy signal manipulation in post production and recording.Q3
The Radial Q3 is a 500 series induction coil EQ that brings the character and excitement of old-school vintage EQ to your recordings with over 1700 EQ curves.Phaze-Q
The Radial PhaseQ is 500 series phase alignment tool that lets you combine two microphones and bring them into perfect phase for a more natural tone.Twin-Servo
The Radial Jensen Twin-Servo & 500 series preamplifier is an updated version of what may well be the most spectacular preamp ever made.PreComp
The Radial PreComp is a 500 series channel strip that combines a state-of the-art preamp with a full-function VCA compressor for dynamic control over the signal.Q4
The Radial Q4 is a 500 series state-variable, 100% discrete class-A parametric EQ that brings character and warmth to your recordings with minimal artifact
Effects & Routing
The 500 series is all about creative use of signal processing. Radial opens the door with compressors, signal routers, cross-over filters, effects interfaces, phase alignment tools and amp simulators. Finally… amazing tools that let your imagination run wild!EXTC
The Radial EXTC is a 500 series effects send & receive module that lets you incorporate guitar effects into the realm of pro-audio recording.Shuttle
The Radial Shuttle is a 500 series patch and insert panel that lets you bring balanced and unbalanced signals in and out a 500 series power rack.Komit
The Radial Komit is a 500 series one-knob compressor-limiter designed to get great results instantly and add crunch and distortion for unque effects.X-Amp
The Radial X-Amp is a 500 series class-A active Reamper with isolated outputs that lets you send a pre-recorded track to two amps and re-record the new sound.ChainDrive
The Radial ChainDrive is a 500 series signal distribution amplifier that lets you send balanced or unbalanced signals to four outputs and control them independently.Tank Driver
A unique module that lets you to drive a balanced line level signal through the reverb tank in your Fender Twin! Drive spring reverbs of all types and deliver the long trailing shimmering effect that is only possible with a true spring.JDX-500
The Radial JDX Reactor is 500 series guitar amplifier interface that lets you capture the tone of a guitar amp and cabinet without a microphone.Submix
The Radial SubMix is a 500 series mixer that lets you combine 4 instruments such as keyboards or effects into a single audio channel via front panel controls.Tossover
The Radial Tossover is a 500 series frequency divider that lets you separate and process low and high frequencies separately via fully variable controls and slopes.
- CABLES & SNAKES
Comparing Direct Boxes
- Selecting a direct box
- Comparing passive DIs for instruments
- Comparing active DIs for instruments
- Comparing a DI box to use with a violin or cello
- Comparing a DI box for the studio
- Comparing DI boxes for laptop computers and other devices
Selecting a Direct Box
The following 'DI selector chart is designed to help you find the best DI for a given application.
Select instrument DI Box Selector Source Good Better Best Active SB-1 Pro48 J48 Magnetic SB-1 Pro48 J48 Piezo SB-4 PZ-DI PZ-Pre
There are three common questions folks ask us when considering a direct box:
- Do I actually need one?
- What kind of DI should I get?
- How much should I spend?
Do I really need a DI box?
The answer is 'it depends'. A direct box is primarily used to allow you to run a long cable without adding noise or losing signal quality. High impedance signals tend to be much more prone to noise and keeping cable lengths under 8 meters (25 ft) is recommended. A DI box converts the high-impedance of an instrument to a balanced low impedance signal. This enables the instrument signal to travel distances of 100 meters (300 feet) without adding appreciable noise. The output of a DI box is mic level – thus the balanced signal is treated just like a microphone.
When playing live, the mixing desk is usually positioned in the house (front of house or FOH position) which is often 50 to 100 meters away. Most instruments such as bass guitar, acoustic guitar and keyboards are connected to a DI box and mixed at FOH. For the sound engineer, capturing the sound before it is processed by the artist on stage usually makes it easier to amplify the signal as it can be optimized for the room.
In the studio, recording from a separate room (isolation booth) enables the engineer to capture a direct sound from the instrument using a direct box and also add a mic in front of the amplifier to capture the tone generated by the amp. When recording in the control room, you may or may not need a DI box, depending on the tone you are looking for. Most mixer inputs have a 'one size fits all' type of input that may not flatter your instrument. A good DI box is optimized to interface with your mixing desk or recording system by presenting the instrument with the right input impedance. This can take the edge off the instrument for a smoother, more natural sound.
What kind of DI box should I get?
This is like asking what kind of microphone should I buy. Just as there are all kinds of microphones for all types of applications, there are a number of DI box types for the same reason. Just as you could use a dynamic microphone like a Shure SM58 to capture just about anything, you could buy a Radial JDI and be pretty much set. But sometimes, using a condenser mic can give you the extra reach to capture more sparkle from an acoustic guitar or more detail from a voice when recording. An active DI box like the Radial J48 is almost the same.
Like dynamic microphones, passive DI boxes tend to be able to handle more signal level without distortion while condenser mics – like active DIs - generally produce a wider frequency response while being more sensitive. And just as most studios and live stages are equipped with a selection of dynamic and condenser mics, both passive and active DI boxes are often used side by side. The choice usually comes down to personal preference.
A simple rule of thumb:
- If the source is active, use a passive DI box
- If the source is passive, use an active DI box
So if you have an old Fender Precision bass with magnetic pickups, an active DI box will probably work best as the buffer will generate plenty of signal for the PA system while reducing the load on the instrument. If on the other hand you have a new, high output active bass with a 9 volt battery inside, you can turn up your volume with confidence knowing that your passive Radial ProDI will easily handle the signal without distortion.
Over the years, industry standards become common place. For instance, most engineers prefer to run an acoustic guitar through an active DI like the Radial J48. On AC powered devices like keyboards, electronic drums, DJ mixers and other active sources, most engineers prefer to use a passive DI like the Radial ProD2. This is because passive DIs can handle more level without distortion and they are also really helpful when it comes to eliminating hum and buzz caused by ground loops.
How much should I spend on a DI box?
We recommend that you follow the 5:1 rule: if you spend $1000 on an instrument, you should probably invest $200 in a direct box. So if your guitar is worth $500, sending $100 on a direct box is probably the right ratio. In our view, there is no point in spending $200 on a DI box if your guitar is only worth $200.
Think of it this way: would you spend $2000 on a great guitar only to play through a $30 guitar amp? Probably not. A DI box is a unity gain preamp. Preamps can cost anywhere from $30 to $10,000. And just like guitars, basses, keyboards and studio preamps - direct boxes come in all shapes, sizes and quality levels based on your expectations. There is no shortcut to quality. Radial DIs are used on the world's top stages and in the best studios because they are designed to deliver the utmost quality day in and day out. We are confident that once you listen to the difference, you will come to appreciate the benefits.
Radial DI boxes come with a 3-year transferable warranty which means that if you decide to sell your Radial DI within the warranty period, the warranty will still be good for the next owner. And because Radial DIs are in demand, they tend to have a much higher resale value.
As described above there are no hard fast rules. It comes down to taste and application.
Comparing passive DIs for instruments
When comparing passive DI boxes, begin by considering the instrument or audio source, the number of channels required for a particular setup and the feature set. You will find that most passive DIs share features such as an input pad and a ground lift. All Radial DIs have built-in filters to reduce parasitic noise caused by magnetic fields and radio frequency waves.
The primary difference between the various models is the type of transformer that is employed. We spend hours listening to various transformers to find the best one for a given application and price point. For instance, the industry standard Radial JDI employs a USA-made nickel core transformer with dual faraday shields and a MuMETAL® external can. MuMETAL® provides upwards to 10,000 times greater shielding than aluminum. This combined with the steel outer shell protects the sensitive high impedance signal from outside magnetic fields from power transformers that can pollute the signal. The JDI, JD6 and Duplex are exceptionally linear from 10Hz to 40kHz. The ProDI employs a similar custom-made transformer that is made off-shore that is also equipped with a MuMETAL® shield. The ProDI, ProD2, ProD8 share the same Eclipse transformer. It is linear from 20Hz to 18.5kHz and works extremely well for live touring. The Stage-Bug SB-2 employs a copper shielded transformer that delivers great performance from 40Hz to 18kHz making it ideal for weekend club dates and jamming with friends.
While the industry standard Radial JDI is primarily intended instruments such as bass, acoustic guitar and keyboards, the two-channel Duplex adds greater connectivity for AV applications where you may need to connect to CD players, video machines and so on. The same follows with respect when looking at the Radial Pro series. If you are using the DI in a live situation and the PA system is band-limited to 18kHz, you may find that the ProDI will work perfectly well. If on the other hand you are recording in the studio you may want to capture the very highest harmonics, the JDI may be a better choice. The Radial JDI is used by Tony Levin, Chick Corea, and The Who while the Pro series DIs like the ProD8 are used by U2, Rush and the Rolling Stones.
Comparing active DIs for instruments
Radial produces a number of active DI boxes to address various requirements. Selecting some, such as the J33 for a turntable, is easy... while choosing between others can be confusing. This section aims to simplify the process by bringing various active DI boxes together for comparison.
For the most part, active DI boxes are employed on instruments. Like condenser microphones, active DIs tend to have more reach over passive counterparts due to the sensitivity of the input. But as with all amplifiers (an active DI box is in fact an amplifier of sorts) these can distort if the input exceeds the available headroom. More headroom can be achieved by increasing the size, or power generated, by the supply. For instance, a DI box like the JDV employs a 30 volt, 400 milliamp power supply that has incredible headroom, but it needs to be locally powered. This may not be convenient on a live stage. Thus the reason most live engineers prefer to use an active DI box that derives its power from the 48 volt phantom power generated by the mixing // console. Phantom power generates 48 volts but only 5 to 10 milliamps of current. Innovative powering schemes such as the one employed inside the J48 elevate the headroom to an acceptable level. This enables most instruments to be connected without fear of distortion and is likely the reason the J48 is used on the biggest stages by the biggest acts around the globe.
The J48 and Pro48 are primarily designed for live stages. These employ similar audio signal paths and derive their power from 48V phantom. The Pro48 is basically a trimmed down version that eliminates the stereo to mono merge function and high pass filter while reducing the size. This enables us to reduce the price to make it more affordable.
The JDV is primarily designed for studio. The over-sized power supply and class-A circuit delivers tremendous dynamic range, and because of the unique zero-feedback design, it produces a very open sound. This has made it a favourite with artists like Marcus Miller and Victor Wooten who are known for their incredibly dynamic playing. Drag control load correction further advances the tone - allowing the artist to optimize the sound of the circuit by properly matching the instrument's load. The JDV is all about purity.
The Firefly is a tube direct box designed to introduce character by driving the signal through the 12AX7 tube and Radial output transformer. This adds warmth and depth that folks often characterize as 'vintage sounding'. The tube circuit necessitates a special high output power supply to provide sufficient voltage to the heater (tube filament). As the newest in the family, it enjoys extra features such as Drag control, a fully variable high pass filter to eliminate resonance, dual selectable inputs and remote controllable mute function.
Selecting the right DI box for a violin, viola or upright
Most string players tend to use a piezo pickup that mounts directly on the bridge of a violin, viola or upright bass. Although piezo manufacturers rarely publish the optimal impedance for their device, piezo transducers sound fuller, warmer and less peaky when they are connected to a very high input impedance. So if you are looking to produce the most natural sound of the instrument, a high input impedance in the range of 5 to 10 meg ohms is ideal. Radial offers several products that meet this criteria.
The difference between these four products comes down to controls and features. For example, the StageBug SB4 is very basic with an input and two buffered outputs to feed the stage amp and the PA system. The PZ-DI takes this up a step by providing a variable low cut filter for precise low frequency control. The PZ-Deluxe adds a 3-band EQ for tone shaping while the PZ-Pre gives you a second channel for another instrument plus an effects loop and power booster for soloing
Using effects on a violin or viola
If you plan to use effects pedals – as commonly used with electric guitar, there are a couple of ways to approach your setup. The first thing to consider is your clean tone. If you connect the piezo to a guitar pedal, you will likely find that the buffer inside the pedal will range from 10k to 1 meg ohms. As described earlier, the higher the input impedance the better. For example, a Boss GE7 tuner has an input impedance of 1 meg-ohms which is a bit low, but will work.
From the input buffer (first device in line), if you can then drive your various effects pedals... and then send the signal to a direct box. The choice of direct box depends on a few factors, but as a rule of thumb, when the signal is already buffered, we generally suggest a passive direct box like the Radial JDI or ProDI. A passive DI will generally be a bit quieter than an active one due to the noise cancelling benefits of the transformer isolated signal path.
The PZ-Pre has the advance of a built-in effects loop. This gives you a 10 meg-ohm input impedance, full on board EQ, a low cut filter to eliminate resonance, and lets you add effects when you need them – or take the out o the signal chain when not in use.
Comparing DI boxes for the studio
When it comes to selecting a direct box for a recording studio, the options are numerous, depending on what you plan to record. Just as many studios have a multitude of microphones, most top studios have a wide selection of direct boxes to suit various needs as well. As a direct box is most often used to record direct, the best way to approach making a decision on which DI to get is by considering which instrument will be recorded.
Recording Electric Bass
Recording bass direct is the most common application for a DI box. As a rule of thumb, when the bass is passive, like an old Fender, using an active direct box will bring out more from the instrument. Our most popular active direct box is the J48. If, on the other hand, your bass is active – with a built-in battery powered preamp, running one buffer (the bass) into another (the DI) does not provide any benefit. We recommend a passive direct box like the Radial JDI for this. Transformers have the benefit of rounding out the tone like a very subtle compressor. For more character, you can use the Firefly tube direct. For more accuracy, the JDV would be the choice.
Recording a Passive Bass Good Better Best Pro48
Recording a Active Bass Good Better Best ProDI JDI Duplex
Recording Electric Guitar
There are two ways to approach recording an electric guitar using a direct box. To capture the sound of the amplifier and loudspeaker, the JDX is particularly effective. Unlike a microphone that changes sound depending on where it is position, the JDX will always sound the same as it is hard-wired after the amp. Using a direct box before the amp (straight from the guitar) will of course only give you a clean guitar sound. When guitars are recorded this way, it is usually for Reamping or to use some sort of digital amp modeling inside the computer. The Radial J48 has a 220k input impedance that makes it sound nice with magnetic pickups. This can be used with the X-Amp for Reamping. For more control, you can use either the Firefly tube direct or the JDV class-A direct as these both have Drag Control load correction.
Recording a Guitar Amplifier Best JDX
Recording a Clean Electric Guitar Good Better Best Pro48
Reamping a Clean Track Good Better Best Pro-RMP
Recording Keyboards and Electronic Drums
As today's digital keyboards are almost always stereo and have a buffered or built-in preamp - when recording - we tend to recommend a passive DI like the Radial ProD2 or Duplex, both of which are equipped with Eclipse transformers. Because the transformer isolates the instrument from the recording system, passive DIs are particularly effective at blocking stray DC voltages in the audio path which manifest themselves in the form of hum and buzz – commonly known as ground loops. When pushed hard, a transformer will saturate, producing a natural compression that is often referred to as vintage sounding. This 'secret weapon' is used by studio professionals to tame the excessive dynamics that drum machines, synthesizers and digital pianos can produce.
Recording Electronic Keyboards Good Better Best ProD2
Recording Acoustic Guitar
For the most part, acoustic guitars are recorded using a microphone. This enables the engineer to mix some of the room ambiance with the instrument. However, when recording in less than ideal acoustic spaces, recording direct can produce very pleasing results. If you are using a piezo pickup without any form of preamp, you will get the best results with a PZ-DI as it has a 10 meg ohm input that will properly load the pickup. If you are recording an acoustic with a built-in, battery powered preamp, then the J48 (active) or the JDI (passive) would be a better choice. The active J48 will have more reach – somewhat like a condenser microphone while the passive JDI will produce a smoother sound due to the transformer's natural compression and warm Bessel curve.
Recording Acoustic Guitar with: Good Better Best Ultimate Active System SB-1
Magnetic Pickup SB-1 Pro48 J48 JDV Piezo Transducer SB-4 PZ-DI PZ-Pre
Recording Upright Bass
When in a professional studio, upright bass is usually recorded using a microphone as this enables you to capture some of the natural room ambiance along with the instrument. Engineers will often add a direct feed from a pickup and mix the sound with the microphone. The pickup itself is most often a piezo transducer of sorts. These sound best when they are presented with a very high input impedance. The PZ-DI is ideally suited for this as it has a 10 meg ohm input. By phase adjusting the PZ-DI so that the fundamentals coincide with the microphone, you can create a very natural tone with tones of body. The Radial Phazer is a great tool for this.
Recording an Upright Bass Good Better Best Ultimate Piezo Transducer SB-4 PZ-DI PZ-Pre JDV
Radial offers several variations of the DIs mentioned here to suit technical requirements and budgets. When we say best or ultimate, in many cases, this depends on the application and features that may be required. Please visit the Radial web site for more information.
Comparing DI boxes for laptop computers and other devices
Today, the use of computers is omnipresent in the audio world. Computers are used to create sound files to back up the band's performance, to play back videos and for walk-in and walk-out music during a concert. The problem with computers is that they are often the cause of buzz and hum in audio systems
DI boxes for laptop Good Better Best SB-5 ProAV2™ JPC
Radial produces a variety of solutions for computers, sound cards and consumer music players. These are broken down into two groups, one being passive, the other active. Many stage techs prefer passive DIs like the ProAv2 as they do not require power and the transformer isolation benefits by eliminating stray DC currents which in turn can cause hum and buzz on the audio line. Active DIs benefit by enabling the electronic designer to add features such as buffers for additional gain and blocking capacitors which can filter out noise without affecting the audio signal path.
The Stage Bug SB5 is designed to provide the system tech with a handy pocket sized direct box with a permanently attached 3.5mm stereo input cable that is impossible to lose. The SB5 delivers good quality audio with choice of mono XLR out to save channels or dual ¼" TRS out for full stereo.
The ProAV1 gives the AV integrator a tool that is equipped with 3.5mm, RCA and XLR inputs to handle just about any situation. It automatically merges stereo signals to mono to reduce the mixer channel count. The Eclipse ET-DB2 is able to withstand higher signal levels for a cleaner more robust output.
The ProAV2 employs two Eclipse ET-DB2 transformers for fully discrete two-channel operation. This preserves the stereo channel while providing plenty of headroom for extra high output consumer level devices such as CD players, iPads and DJ mixers.
The Duplex is Radial's flagship passive direct box. It employs two Jensen JT-DBE transformers for the ultimate in signal handling without introducing distortion, phase shift or artefact. This makes the Duplex the preferred choice for Broadcast, high end recording and the most demanding concert touring installations.
The JPC is a stereo direct box that combines a buffered audio circuit with isolation transformers that together block both stray DC and digital noise generated by computers from leaching back into the audio system. It is phantom powered for easy integration into a live PA setup.
The Radial J+4 is 'technically' not a direct box, but a stereo preamplifier. This is designed to take low level signals and boost them so that they can be sent to +4dB balanced line level devices. For instance, this handy device can take an iPod and send it to an aux input of a mixer if all the mic channels are in use.
The USB-Pro is a direct box that takes the digital output from a laptop computer and converts it to analog. This features full 24bit, 96kHz processing for maximum fidelity and switchable isolation transformer to eliminate hum and buzz caused by ground loops. A built-on headphone amp lets you monitor the signal for trouble shooting.
The J33 is a specialty direct box designed for turntables equipped with a magnetic cartridge. The built-in RIAA curve sets the tone and delivers the phono output to both a -10dB unbalanced RCA set for hookup to a hifi system and balanced -20dB output to feed a mixing // console.