Your Holy Grail DI for Bass and Guitar
If you think of direct boxes as utilitarian devices designed to get an XLR-compatible signal out of a bass or guitar, then Sweetwater has a nice surprise for you. Enhancing clarity, detail, and dynamics, the Useful Arts BF-1 goes way beyond basic DIs. A do-it-all interface for any instrument with a pickup, the BF-1 is used between instrument and amp, instrument and PA or recording device, or all of the above. Everything you plug into it instantly sounds better — not because it changes the sound of your axe, but because it preserves the native sound of an instrument more effectively than any amp or console input stage. You'll be amazed at how good the Useful Arts BF-1 will make your instrument sound.
Related Videos: BF-1 Tube Instrument Preamp/DI
It all comes down to input impedance
So what's the story? The signal output by magnetic pickups is gorgeous, highly detailed, and pitifully weak — piezoelectric pickups even more so. It's not simply a question of signal level (voltage); what's at issue is the power of the signal (current). All amplifiers make signals work to drive their input stages. The problem is that the most nuanced (the weakest) parts of the signal aren't up to heavy lifting and are lost forever. It all comes down to input impedance.
20 million ohms
The higher the input impedance, the less work a signal has to do in order to be amplified. The typical input impedance of consoles and recording devices is usually about 10,000 ohms — much too low for a pickup. That's why a bass or guitar plugged directly in sounds small, lifeless, without detail and bottom end. Thin and buzzy, piezo pickups sound even worse. The input impedance of guitar and bass amplifiers is typically around several hundred thousand ohms — a major improvement that makes instruments sound bigger, fuller, and more detailed. This is why the traditional method for recording or live gigs is to run the instrument into a direct box for the console and back out to the guitar amp. The DI replicates the input impedance of the amp and converts it into a console-friendly signal. So far, so good. But Useful Arts takes the equation further. What if, instead of a few hundred thousand ohms, a DI had an input impedance of 20 million ohms? Enter the BF-1.
Using an input tube for massive impedance conversion
Setting out to design the BF-1, Useful Arts determined that tubes — as they are inherently capable of creating ludicrously high input impedances — were uniquely well suited for the job. Passive DIs utilize transformers, which cannot effectively create such high impedances. Active DIs employ low-voltage FETs, which sound like, well, transistors, and typically offer input impedances far lower than a good tube stage to boot. The BF-1 uses its input tube the same way a tube microphone does — to convert impedances in the absence of high gain. Even your tube guitar or bass amp sounds better when fed from the BF-1, courtesy of a better-sounding signal at its input.
But wait, there's more…
Massive impedance conversion is impressive, but the BF-1 isn't a one-trick pony. Also onboard are a Class A tube preamp, a 2-band equalizer, and two outputs you can use to simultaneously feed your amp and console. But there's even more. Bypassing the EQ gives you a choice of low gain (like a conventional DI) or high gain, which lets you go straight into converters for purist hi-fi line-level recording — no other amplification required. For bassists, the BF-1 can negate the need for an amp altogether. Feed a console with the tubes in the BF-1, and it will rival or exceed any bass amp you've ever used. Crank the EQ's low band and kiss the venue's windows and drywall goodbye.
Useful Arts BF-1 Tube Instrument Preamp/DI Features:
- Input impedance of 20 million ohms
- Class A tube preamp
- 2-band equalizer
- Output gain control
- Lo Gain or Hi Gain operation
- Pure mode for hi-fi line-level output
- Front-panel Input and Thru jacks
- Rear-panel balanced XLR and unbalanced 1/4" jacks
