Radial Engineering Firefly DI Box Review

Aloha!

I have amassed quite a collection of DI boxes, and I have to say that my favorite of the bunch is the Radial Engineering Firefly, which is also the priciest of the bunch. This is not too surprising, I suppose…

Radial Engineering builds an impressive collection of products, including one of my favorite passive direct boxes, the JDI (which I still need to write a review of…). None of their stuff is cheap, as they use quality components and their boxes are built with workers earning first-world wages in Canada.

Firefly is big and heavy for a DI box, measuring around 5.25 x 8.25 x 1.75 inches, and coming in at a bee’s dick under 4 pounds. This is a solid piece of work with a gnarly 16-volt external power supply and depending on how you want to use it, you might want to spring for the optional rack mount kit. No matter how you use it with the quality of its construction it should last you for years and years of studio and/or road work.

On the back you will find the sockets for the power supply as well as two ¼-inch input jacks. These allow two guitars to be plugged in, although only one of the signals can be used at a time. They are switched with the select switch on the front panel or with the optional footswitch. There are LEDs for each channel so you know which one you have selected, and each one has its own trim pot. There is also a ¼-inch “Insert” that allows you to run effects straight into the unit for both channels.

The outputs on the back are a balanced XLR out and an unbalanced auxiliary ¼-inch out. This means you can run the ¼-inch out to your stage amp and the XLR to the mixing board. Or a recording console. There is an extra ¼-inch tuner out too.

Some other extras (also on the back) are little tiny ground lift, phase polarity, and pre-post switches. The pre-post switch will change whether the amplified signal comes before or after the tube. Mmmm. tube.

Besides the channel trims, the other controls are simple, yet innovative. There is a Level knob that controls the master volume for both outputs and a Low Cut control that works below 500Hz. It will go down to -25dB at 100 Hz. The super-neat feature is load adjustable drag control, so you can change the stock impedance its preset 3.9 MΩ. The stock setting is good for active pickups and passive piezo units. By using the controls range of 22 kΩ to 500k Ω, you can get the most out of the Firefly with a wide assortment of passive magnetic pickups. This kind of flexibility is astounding.

I forgot to mention that the optional footswitch also has a mute switch. Maybe I should see about getting one of those.

The Firefly does the basic DI stuff, which is making a low-impedance balanced signal out of your bass’ high-impedance unbalanced signal. It is amazingly quiet and natural sounding, and it has a frequency response of 20 Hz to 20 kHz. These things are pure heaven to work with when they are plugged into your board. But it does a lot more and really ends up being a kick-butt preamplifer too.

You see, this Radial unit has a Class A FET front end and a 12AX7 tube drive circuit. The tube gives the output sound a new level of warmth and robustivity. This is universally true with every instrument I plug into to it. I have tried it with a plain-old passive P-bass, my active Sadowsky, and even 18-volt Kubickis, and Musicman Bongos, and they all came out sounding better than they do dry. Having two inputs channels is really handy for having an active and a passive bass plugged in, so you can set levels for each of them and then leave them alone.

The Firefly is not just for basses, though I hear it works marvelously on double basses too. I have used it with my Stratocaster and my Martin D-18GE (with an add-on K&K Pure Mini pickup), and it killed with them too. This might be a keeper.

The only thing I am lukewarm about is the drag control. I have messed around with it and only saw small changes in the tone, and perhaps not enough of a change for me to even want to mess with it anymore. Still, this is not a deal-killer by any stretch of the imagination, and I am sure there are some aficionados that would give their left nut to have this feature.

So, the Radial Engineering Firefly is the best direct box I have ever tried, and if you want one there will be a hefty price to be paid. It has a list price of $700 and a street price of $599, though some sellers will knock it down to fewer than 500 bucks if you haggle a bit. It is worth every penny…

Mahalo!