Burl Audio B1 — a mono microphone preamp and DI in the 500 Series format, with a BX3 input transformer and a nickel-core BX2 output transformer, giving a cleaner, more open depth than the iron-core BX4 in the B1D.
The signal path is fully discrete, class-A, direct-coupled, with no capacitors. The preamp offers 70dB of gain, stepped gain control, independent output level control, an impedance switch, a 30dB pad, and a front-panel 1/4" DI jack.
Transformer saturation under full control
Many engineers want the dense, saturated tone a transformer can add on vocals or acoustic guitar, without risking an overloaded output. The B1 addresses this with independent gain and output level controls: turning up the gain pushes the signal into the nickel-core BX2 transformer for saturation, while pulling down the output level keeps the final level in check. A tri-colored LED shows whether the signal is light, right in the pocket, or already driven hard.
One preamp for mic, instrument, and line signal
A tracking session rarely sticks to one type of source, and switching between separate preamps for mic, guitar, or line signal eats up time. The B1 addresses this by combining an XLR mic input with phantom power, a front-panel DI jack for guitar or bass, an impedance switch for ribbon mics, and a pad for hot line-level signals, all in one 500 Series module.
KEY FEATURES
- 500 Series format, VPR Alliance compliant
- BX3 input transformer and nickel-core BX2 output transformer
- Discrete class-A signal path, direct-coupled, no capacitors
- 70dB of gain with stepped gain control
- Independent output level control
- Input impedance switch
- Front-panel 1/4" DI jack
- -30dB pad for hot signals and line inputs
- Phantom power and phase switch
- Tri-colored signal level LED
TECHNICAL SPECIFICATIONS
- Type: mono microphone preamp/DI, 500 Series
- Gain: up to 70dB
- Input transformer: BX3
- Output transformer: BX2 (nickel core)
- Signal path: discrete, class-A, no capacitors
- Pad: -30dB
- Inputs: XLR mic, 1/4" DI (front panel)
- Phantom power: yes
- Phase switch: yes
- Level indicator: tri-colored LED
