Sadowsky’s MetroLine series occupies a specific and interesting position in the bass market. It’s not the NYC Custom Shop — those instruments are handbuilt in New York at prices that reflect it. The MetroLine is Sadowsky’s German-made production line: the same preamp design, similar pickup voicing, significantly more accessible pricing.
I spent time specifically testing the EQ and pickups on a MetroLine Jazz-style bass. Not a general overview — a focused session on what the preamp actually does to the tone and whether the active/passive interaction is as good as the reputation suggests. Here’s what I found.
The Sadowsky Preamp — Why It Has the Reputation It Has
The Sadowsky outboard preamp became famous before the bass line did. Roger Sadowsky designed a boost-only 2-band EQ in the 1980s that studio and session players adopted widely because it added presence and life to passive basses without changing their fundamental character. The concept was simple: boost only, no cut, with voicing chosen specifically to complement Jazz-style pickups.
The onboard MetroLine preamp carries this philosophy into the instrument itself. Bass boost at the low end, treble boost at the high end — both starting from a flat centre position. There’s no mid control. The philosophy is that the pickups handle the mids and the preamp handles extension at the frequency extremes.
This is a different design approach from most active basses that offer full 3-band EQ with boost and cut on each band. Whether it’s better or worse depends entirely on what you need from your electronics.
Testing the EQ — What Each Band Actually Does
The bass boost on the MetroLine preamp is centred low enough that it adds genuine foundation without creating mud. A small amount — maybe 20-30% of the available boost — adds a richness and warmth that makes the bass feel bigger in the room. Push it further and you get more obvious low-end weight that works for certain styles (R&B, soul, slow grooves) but can become too much for busy arrangements.
The treble boost is where the Sadowsky character becomes most apparent. The frequency centre is chosen to add air and presence rather than harshness. It makes single notes more defined and articulate without introducing the brittleness you can get from boosting 4kHz or above on a standard 3-band EQ. A small treble boost transforms slap bass in particular — the snap and pop of the attack comes forward in a way that doesn’t require raising the overall volume.
With both boosts engaged at moderate levels the MetroLine has a full, present, studio-ready tone that sits in a mix with very little additional processing. This is the design intent and it works exactly as described.
The Passive Bypass
The MetroLine includes a passive bypass switch — pull the volume knob and the preamp is bypassed completely, running the pickups direct. This is genuinely useful and reveals something interesting about the pickup design.
Passive, the MetroLine sounds like a good Jazz-style bass — warm, slightly rounded, with the characteristic single-coil character. The hum-cancellation design (which varies by configuration) keeps the noise floor manageable. It’s a functional passive tone that you could record or gig with directly.
Active, the same bass becomes more assertive. The frequency extremes open up, the presence increases, and the instrument sounds more confident in a mix. The transition is noticeable but not dramatic — it doesn’t sound like a completely different bass, it sounds like the same bass with enhanced extension.
This relationship between passive and active is a design success. The pickups are voiced to work well in both modes rather than being designed only for active use.
Slap Mode — The End of the Video Moment
I want to address the slap tone specifically because it’s the most dramatic demonstration of what the Sadowsky EQ does. With the treble boost pushed to around 60-70% and the bass boost at moderate levels, the MetroLine produces a slap tone that is genuinely exceptional.
The thumb attack is percussive and defined. The string pop cuts through with a presence that sits above the midrange clutter of a full band. The low end stays fat without getting sloppy. This is the tone that made Sadowsky famous in New York session circles in the 1980s — the sound that worked perfectly on studio recordings where every element needed to be present and defined.
For slap bass players specifically, the MetroLine preamp is one of the better tools available at its price point. The boost-only design is not a limitation for slap — it’s an advantage, because you’re adding presence without changing the fundamental character of the attack.
MetroLine vs NYC Custom Shop
The honest comparison: the MetroLine captures the Sadowsky preamp character accurately. The EQ behaves the same way, the voicing is similar, the passive/active interaction works as designed. What the NYC Custom Shop offers beyond that is higher-grade components, hand selection of tonewoods, and the individual luthier attention that comes with custom shop pricing.
For players who want the Sadowsky experience without the NYC Custom Shop investment — the MetroLine delivers the most important elements. It’s not a budget alternative; it’s a genuine Sadowsky with a different production methodology.
Who Should Consider the Sadowsky MetroLine
Session players and recording bassists who want a studio-ready active tone. Slap bass players who want a preamp specifically voiced for that technique. Players upgrading from standard active basses who want a more musical, less clinical EQ character. Anyone who’s tried a Sadowsky outboard preamp and liked what it did to their existing bass.
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FAQ
What is the difference between the Sadowsky MetroLine and NYC Custom Shop?
The NYC Custom Shop instruments are handbuilt in New York with individual luthier attention, hand-selected tonewoods, and custom specifications available. The MetroLine is produced in Germany on a more standardised production line using the same preamp design and similar pickup voicing. The MetroLine captures the most important Sadowsky characteristics at a lower price point.
Why does the Sadowsky preamp only have boost and no cut?
Roger Sadowsky’s design philosophy is that boost-only EQ sounds more musical than boost/cut designs. A boost-only preamp adds presence and extension without the phase issues and tonal thinning that can occur with cut-heavy EQ. The pickups are voiced to sound good flat — the EQ adds, it doesn’t subtract.
Is the Sadowsky MetroLine good for slap bass?
Excellent for slap. The treble boost’s frequency centre is voiced specifically to enhance slap attack — the snap and pop come forward with presence rather than harshness. Many session players consider the Sadowsky preamp one of the best tools available for slap bass tone.
Can I use the Sadowsky MetroLine passive without the preamp?
Yes — the MetroLine includes a passive bypass (typically a pull-up on the volume knob) that bypasses the preamp completely. The passive tone is functional and musical on its own. The active preamp enhances it rather than being required for the bass to sound good.
How does the Sadowsky MetroLine compare to a standard active Jazz Bass?
The main difference is the preamp voicing. Standard active Jazz Basses typically use 3-band boost/cut EQ. The Sadowsky uses a 2-band boost-only design that sounds more organic and less clinical when boosted. Players who find standard active basses too “hi-fi” or processed often respond positively to the Sadowsky character.