Bacchus JT WL4-SPM RSM/M NAS

Essential Information About the Bacchus JT WL4-SPM RSM/M NAS Bass

• Modern and versatile "JB" spirit: Original JB pickup set, ideal for switching from crisp funk to heavier rock.


• Roasted maple neck and fingerboard: silky feel, improved perceived stability, and fast playing sensation, perfect for precise lines.


• Effective controls in any situation: 2 volumes + 1 tone, with a push/pull "turbo switch" to instantly thicken the sound.


• Natural Satin open-pore finish: natural look, comfortable grip, and the instrument comes ready to play with a gig bag and adjustment wrench.

Japan Tune-up: a WL4 designed for playability, without frills

The Bacchus JT WL4-SPM RSM/M NAS belongs to the Japan Tune-up series and follows a "stage instrument" approach: an S-type design, a natural satin aesthetic, and straightforward electronics focused on efficiency. Within the WL family, this 4-string model stands out for its passive and intuitive orientation, offering an expanded tonal palette via the turbo switch while maintaining the simplicity of a bass with two volumes and one tone control.

For whom and for which styles?

With its narrow nut and 4-string format, the WL4-SPM RSM/M is well suited for serious beginner bassists as well as intermediate players seeking a comfortable, stable, and easy-to-adjust bass. Experienced players will also find a reliable tool designed for rehearsals and gigs, thanks to familiar ergonomics and hassle-free electronics.

Regarding styles, the "JB" configuration is comfortable across a very wide spectrum: funk (sharp attacks, articulated mids), pop (round and clean tones), rock (present low-mids, good pick attack), jazz and neo-soul (finger nuances, dynamics). The turbo switch adds useful density when filling the mix or making a bass line stand out without excessively raising the volume.

A "JB" tonal personality, balancing clarity, grain, and thickness when needed

The heart of this bass is its Original JB Set: two pickups with a "single-coil" character, renowned for their definition and dynamics. At the neck pickup, you get a round and enveloping foundation with comfortable lows to support the band. Moving toward the bridge pickup, the sound becomes more aggressive, more "singing" in the mids, perfect for precise lines, ghost notes, and grooves that need to remain clear.

The 2 volume control section allows fine blending of the two pickups: you can shift from a wide and balanced sound to more characterful tones without changing your playing style. The tone control acts as a true musical tool: open, it preserves all the attack and air in the high spectrum; closed, it smooths the output for more vintage, "woody" sounds, very effective for fingerstyle playing.

The pull-up turbo switch (on the tone) provides an immediate sonic change: more body, a more present perceived level, and reinforced low-mid foundation. This is especially relevant for moving from a clean verse to a denser chorus or for maintaining a solid bass line when the arrangement thickens (distorted guitars, keyboards, prominent kick drum).

The craftsmanship also contributes to the feel: the roasted maple neck and roasted maple fingerboard promote a crisp attack and good precision, while the JB Bridge with brass saddles contributes to a firmer response and more consistent attack, useful for both pick and finger nuances. The open-pore finish offers a "natural" feel under the hand and enhances the impression of a lively, direct instrument.

Recommended compatible accessories

To stay as close as possible to the original setup, you can consider a D'Addario XL-165 string set (the same reference as the factory setup). A strap is also a safe and relevant choice for rehearsals and stage use, especially since the instrument comes with a gig bag for transport.

Technical specifications

Left handed	No	Nbr of strings	4
Strings	Steel

Category	bass	Radius	12" / 305 mm (305R)
Shape	TYPE S	Number of frets	21
Orientation	right-handed	Frets	Nickel Silver
Body	Natyoh	Nut width	1.50" / 38.0 mm
Body/Top	roasted maple	Nut material	PPS
Top color	NAS	Bridge	JB Bridge with brass saddles
Finish/color	Natural Satin	Tuners	OpenGear
Finish	open-pore	Pickup	Original JB Set
Weight	3.9 kg	Functions/controls	2Vol, 1Tone (Pull-up \= turbo switch)
Country of origin	Indonesia	Series/range	Japan Tune-up
Neck	roasted maple	Number of strings	4
Fingerboard	roasted maple	Included accessories	gig bag, adjustment wrench
Scale length	34" / 864 mm