Radial J48 MK2 48V Phantom Power Active Direct Box

What is a DI (AKA a Direct Box)?A DI is basically a device that in the most basic sense electrically isolates and transforms unbalanced line level signals (signals from most stage instruments and most consumer electronics) to balanced line level (on both powered and unpowered lines) singnals commonly found on PAs and stage mixers used for mics. There are two categories...Passive and Active. Passive DIs do not require any addition power source like batteries or AC input. They are simply a transformer that transformed the input signal to an output signal. I will skip the physics of it though. Active DIs are a little more complex and generally cost more. Sound quality on cheaper models can be horrible. These DO require additional power such as batteries or "Phantom Power" on the higher end units. Without getting too deep into the physics here, these depend on the unit's "rail voltage" to prevent clipping. The more dynamic the insturment and performance, the more rail voltage you'll need. This unit features a rail voltage of around 9V which is much higher than comparable Active DIs. This is important with the modern generation of pre-amplified (powered) acoustic guitars, active basses, ect as these signals can be quite dynamic electrically.Why do you need a DI?Whether your using an instrument or a multimedia device like a DVD, iPod, or laptop...these will almost always be unblanced line level outputs either thru 1/4" jack, 1/8" jack, or RCA jacks. Just using a cable adaptor to mate these with the common 3-pin XLR for balanced line level signals found on PAs and mixers will at the very least create problems with loss of signal, and unwanted buzz and hum. And at the worst (and actually very likely with Phantom Power) short out your device. PAs that use Phantom Powered mic lines and these will instantly overpower any device mentioned above. Instead you need something to transform and isolate the two halfs of the system. This devices transformer and circutry does just that. Also even on a mic line that is unpowered, there is a risk to the pre amp in the PA when sending unbalanced line level signals to it. In other words... Buy a DI!The details. This unit is a powered unit that requires 48V Phantom power to be on the XLR line to supply the unit with power. It has an indicator light that shows Phantom power but stays on only momentarily. On the input side you get a 1/4" in and 1/4" thru for passing to a stage amp. Or you can use "merge" button and combine the two jacks to convert a L and R stereo signal to mono. Nice for multimedia and keyboards. I'm using a Hosa 3.5mm TRS to Dual 1/4 in TS (1/8" stereo jack to dual mono 1/4" jacks) for one of my applications. On the input side is a "pad switch" to signals that are really dynamic and may potentially clip. On the Output side is a single balanced XLR output (1 channel mono), a 180 degree "flip switch" for reversing polarity to work with foreign made sound equipment. It has a ground lift switch to isolate grounds and get rid or noise due to ground loops. Because it is a powered unit and has electronic circuitry they have included some extra isolation to protect the signal and preserve that continuity for the power supply. The device is built to isolate grounds automatically, but if you still have noise you suspect due to grounds, try this. Lastly it features a low cut filter button that is used in preventing feedback. It's small in size, about 4"x6"x1.5" and roughly 2 lbs. It's made of a solid steel case to protect it from damage on stage while at the same time create an "EM cage" to shield the internal electronics from outside interference.This is my 3rd DI from Radial. I have to say at this point I'm a fan of their gear. This unit is definitely a professional quality DI with a reliability and sound quality that tour musicians require but at a price point just about anyone can afford. I bought this one to play by Italia Mondial through, it has an active pickup inside the hollow body and I have to say, it sounds tremendous played through this box. BTY, if you're looking for a Passive DI (one that requires no external power), look into the JDI by Radial. There are cheaper models from them, but this one sounds great no matter what you drive through it.

I bought this DI to use with both active and passive bass guitars and electric guitars. I was a bit concerned that it would not be able to handle the signal from my active bass and electrics, but it works great. Very clean signal, no clipping, no distortion. Easy to use and highly recommended.

I bought this primarily for recording bass tracks, but I’ve been using it for electric guitar, acoustic guitar, and mandolin, too. Rock solid construction - the thing is a tank. Crystal clear sound - no discernible coloration that I can tell. This unit easily handles active pickups on bass and acoustic guitar, passive pickups on electric guitar, and even a very low output passive piezo pickup on a mandolin that is otherwise almost impossible to record without a live mic. I typically use this box to record a DI track in addition to a regular track (with a mic). I haven’t used the “merge” feature, so I can’t comment on that functionality. But it’s done everything I’ve needed it to do. Very happy with the product.

Used one of these in a recording session and was blown away. Bought one for the home studio. I'm tracking an early 70's P-bass into a UAD Apollo and wasn't getting enough LOW END POWER. The J48 made that happen, in spades. I was thinking about getting an Avalon U5, which are also excellent. This just sounds better to me.Now my bass sound has made me famous throughout the land and I'll be retiring to a private island soon. You should get one.OK, maybe that was an exaggeration. But still, it's pretty great.

I bought this DI because my Fender American Jazz Bass has real quiet passive pickups and a passive DI never seems to get me on level. I would always feel kinda awkward asking the audio crew at church to pull out an active DI for me whenever they had the usual passive one in place. One of the guys recommended I get my own J48 to always have handy. It is the same brand but much better quality than the DIs they have on hand usually. I always get compliments on the sound they are getting up at FOH when I play through this. Very clear, never distorted, full frequency response, brings out the richness of the Fender sound.

Having an issue with this Di. Bass amp is working well. If I use the Thru on this DI, it causes a loud buzz in the amp. Now, If i use the ground lift switch, there is a loud buzz in the XLR line going to the mixer.. What am i supposed to do....

Wow! What a great DI! I have this on my list of DIs for a while and after getting another acoustic instrument and need for another DI I finally had the reason to buy it. I already own an LR Baggs ParaDI, Fishman Platinum EQ, and Sans Amp. I have a Collins guitar with a KnK mini and it has been running thru the fishman, with some EQ work I got it sounding good and that's what I've used for a few year. When I got the J48, I plugged my Mandolin in first (usually run thru the Baggs) I noticed right away how much better the mandolin sounded, and it already sounds great thru the Baggs. So I got the Collins and plugged it in and it just blew me away on how natural it sounded without any EQ. I use a Soundcraft Expression Si which is a very good sounding board, I disabled the EQ and it still sounded great. If you haven't figured it out, I'm definitely impressed with the Radial J48 and interested in some of their other products. I've got some other DI on my list to try, but this will be my new goto DI.

The media could not be loaded. Recording electric guitar in the studio with an active Direct Box! I'm using the Radial J48. Well constructed and noise free. The best one I’ve used! The video should answer any questions you may have.