Developer Leigh Pierce is giving away two bass preamp plugins for free: NoAmp Low Rider DI and Obsidian B7000. Both are circuit-level emulations of classic bass DI pedals, and both are available right now at no cost.
Here is a look at what each plugin does, what makes them different from the usual capture-based emulations, and how to download them.
1. What Is Leigh Pierce NoAmp Low Rider DI?
NoAmp Low Rider DI is a bass DI/preamp plugin that reverse-engineers three generations of the Tech 21 SansAmp Bass Driver DI (BDDI). Instead of relying on captures or neural networks, the hardware circuit topology was analyzed at component level and rebuilt in double precision using Wave Digital Filters (WDF). The three revisions – V1 Early, V1 Late and V2 – are selected through a single automatable parameter, and the pedal artwork changes to match whichever revision is active.
Key Features
- Three switchable revisions – V1 Early, V1 Late and V2 – each with its own dedicated pedal face
- PRESENCE, DRIVE, BLEND (dry/wet mix), LEVEL, BASS and TREBLE controls shared across every revision
- V2 adds a post-blend MID control, a MID SHIFT switch for the mid center frequency, and a BASS SHIFT switch for the low end
- The circuits genuinely differ per revision: V1 Early has no clipping diodes and distorts purely through op-amp rail saturation, while V1 Late and V2 add a Zener clipping stage in the drive feedback path
- The tone stack differs as well – V1 Early uses a Baxandall shelving design, V1 Late and V2 use a peaking design
- Input and output trim with VU metering
- Oversampling (1x / 2x / 4x / 8x) configured separately for live playback and for rendering
- Crossfade processing when switching revisions to prevent glitches
- HQ/Eco toggle to balance sound quality against CPU load
2. What Is Leigh Pierce Obsidian B7000?
Obsidian B7000 is a bass overdrive/DI preamp plugin built from the Darkglass B7K Ultra schematic, solved as a Wave Digital Filter from the actual component values. Because no neural capture is involved, the knobs respond the way the real circuit does rather than morphing between captured snapshots. It covers the modern overdrive/DI sound heard throughout rock and metal bass tones, on both the clean and the driven side.
Key Features
- Eight pots: Master, Blend, Level, Drive, Bass, Lo-Mids, Hi-Mids and Treble
- Two three-way toggle switches – Attack (Boost/Flat/Cut) and Grunt, which sets how much low-frequency content is fed to the clipper across three positions
- Two frequency selectors – Lo-Mid at 250Hz / 500Hz / 1kHz, and Hi-Mid at 750Hz / 1.5kHz / 3kHz
- Two independent footswitches for true bypass and distortion. The distortion switch mutes only the overdrive path, so you can leave the plugin on as an always-available clean DI/EQ and kick in the drive only when you need it
- Distortion comes from CMOS inverter overdrive – a CD4049UBE unbuffered hex inverter driven in its soft transition region – rather than diode clipping
- A J201 JFET active gain stage ahead of the clipper adds even-order harmonic character
- Four-band active EQ: Baxandall bass and treble plus two mid peaking bands with switchable frequencies
- Oversampling (1x / 2x / 4x / 8x) configured separately for live playback and for rendering, with first-order ADAA applied to the JFET waveshaper
- Internal voltages modeled in real volts against a measured input reference, so the nonlinear stages clip at the same points as the hardware
Samples used in the demo video come from Splice Sounds: SOULSURPLUS_hiddengems_melodic_loop_3_electric_bass_dry_soul_65_bpm_amin and TS_PUNCH_130_drum_loop_halftime_headmover. Splice official site
3. How to Download and Install NoAmp Low Rider DI and Obsidian B7000
Both plugins are distributed through GitHub. Open each project releases page and download the installer that matches your operating system, then run it as you would any other plugin installer.
Leigh Pierce NoAmp Low Rider DI
Leigh Pierce Obsidian B7000
That covers the free release of NoAmp Low Rider DI and Obsidian B7000. If you play bass in the box, two circuit-accurate takes on the SansAmp BDDI and the Darkglass B7K Ultra for nothing is about as good as free plugin news gets.