Q: Why do some people feel active direct boxes are better than passive DI’s?
A: Comparing active DI’s to passive ones is akin to comparing condenser mics to dynamics.
Condensers tend to have more ‘reach’ and upper end clarity, while dynamics tend to be bolder and better suited to handling transients without distortion. Active direct boxes are signal preamplifiers that draw very little current from the instrument and because of their higher input impedance, tend to have more reach and sparkle. The high input impedance results in less loading on the pickup, an effect that can cause passive pickups, as found on vintage basses and electric guitars, to sound thinner. Today, most basses and acoustic guitars employ battery-powered preamps that buffer the signal and are not affected by loading. Most pros have some of each depending on the tone they are looking for or the problem they are trying to solve.

Q: If the Radial DI is the best, should I spend more money to buy it?
A: This depends entirely on the sound system you are using. Most PA systems are not capable of producing the bandwidth that comes out of the Radial JDI and therefore, the Radial ProDI is a good solution.

Q: What causes ground loops?
A: When manufacturers build their products, the internal circuit and outer shells are teaming with electrical currents traveling all over the place and returning to the safety ground. This ground reference voltage varies between manufacturers and when two devices are connected together, these ‘stray’ voltages can often combine to create 60 cycle hum commonly known as a ground loop. A good transformer provides an effective solution in reducing this ‘common mode’ noise and is the reason why passive direct boxes are often preferred for live concert touring.

Q: Is the ProD2 two separate DI’s in one?
A: Yes. Each channel inside a ProD2 is completely isolated from the other and is the same as having two ProDI’s in a single box. The ProD2 was designed for stereo keyboards and devices (such as CD players) that need to be balanced.

Q: Can I rack-mount the ProDI or ProD2?
A: The ProDI is not rack-mountable while the ProD2 is. In fact, with the J-Rak, you can jam in 16 separate channels (8 x ProD2) in two rack spaces, making it ideal for large keyboard rigs on tour.

Q: Can I use a headphone out into the ProDI?
A: Yes. Keep volume low and use the pad. Listen for distortion as overly high levels can saturate the transformer.

Q: Can I use a ProDI backwards for re-amping?
A: Yes. Careful on the level as it should be very low: mic level – not line level!

Q: Will phantom-power hurt the ProDI?
A: No, phantom-power is DC and very low current. The ProDI will ignore it.

Q: Can I run a guitar into effects and then into the ProDI for direct recording?
A: Yes! The ProDI will eliminate noise caused by stray voltages and provide a smooth, natural response.

Radial - True to the Music™