Gr Bass One 350 BLK

Historical Context and Positioning in the Range

This amp head fits into the modern approach to bass amps: lots of power in a lightweight chassis, with features expected on stage (DI, Mute, headphone monitoring) and practical daily tools (VU meter, built-in tuner, 9V power supply for pedals). It aims for a clear compromise: ease of use and versatility without the bulk of a rack or heavy combo.

Who This Amp Is For

This head is suitable for the beginner to advanced bassist who wants a reliable amp, easy to dial in and powerful enough to rehearse with a drummer and handle small to medium gigs (notably via the DI to the PA). In the home studio, the 3.5mm headphone output with level control and the fan in Studio mode facilitate quiet work. Regarding styles, its 4-band EQ and Deep/Bright voicings make it comfortable from funk to rock, including pop, metal (sharper attack), and rounder genres like reggae.

Features and Innovations

The heart of the machine relies on a very straightforward control chain: adjustable Gain to set the input level, then Master Volume to manage the overall volume. The 4-band EQ can be activated or bypassed (EQ on/off) to instantly switch from a shaped sound to a rawer tone. Two dedicated switches (Medium and bypass) allow quick curve changes, useful for switching from fingerstyle to pick playing, or from a verse to a denser chorus.

To refine the character, the Deep/Bright switch offers two musical directions: more depth and low-end foundation, or more brightness and definition to highlight the attack. The Mute is ideal for changing instruments, tuning silently, or cutting the signal between songs. The monitoring section includes a 3.5mm headphone output with level control and a 3.5mm Aux input for playing along with tracks, a metronome, or backing tracks.

For stage/studio integration, the head features an external effects loop (handy for chorus, delay, multi-effects, or additional preamps), and especially a DI output with Pre/Post switch to send either a signal before or after EQ. A Ground Lift switch helps reduce hum caused by ground loops. Finally, the 9V DC output powers up to 4-5 effects pedals: an excellent solution for a minimalist pedalboard when traveling light for gigs.

The Sound

Designed as a transistor-based bass head, it prioritizes responsiveness and clarity : tight lows, clear attack, and a rendering that respects the character of the bass (single-coil, humbucker, active). With the EQ off, you get a natural and quick foundation, ideal for laying down a clean sound and letting the playing speak. Activating the 4-band EQ allows precise sculpting: scooping for a more modern slap, thickening the low-mids for dense rock, or opening the high end to cut through a busy mix.

The Deep and Bright voicings provide two effective shortcuts: Deep enhances the foundation and sense of depth (very musical with generous cabinets), while Bright emphasizes definition and articulation (useful for pick playing, harmonics, or regaining presence on stage). The clip LED and VU meter help set the Gain to keep a clean sound with enough headroom and avoid unwanted input saturation.

Technical specifications

Category	Bass amp head	Headphone output	Mini jack, Yes
Technology	Solid state	Color	Black
Effects loop	Yes	Finishing	Aluminum
Category	Amplifier	Power output	350 W
EQ	4 channels

Format	amp head	Speaker output	Speakon
Power	up to 350W (depending on speaker load)	Finish	Black
2 switches	Medium + bypass	Weight	1.9kg
Instrument input	6.35mm Jack	Warranty	3 years
Auxiliary input	3.5mm