Microtubes D7K Ultra V2 (Demonfx) — In-depth Review

This review examines the Microtubes D7K Ultra V2 (Demonfx version) from the perspective of a working bassist and pedalboard builder: what it does well, where it falls short, and how to get the most value from it.

I focus on the product’s core selling points (preamp + distortion, 4-band EQ, blend control, direct out capability), give objective observations about tone and usability, and provide practical recommendations so readers can decide whether it belongs on their board.

First impressions & build quality

The D7K Ultra V2 arrives as a solid, medium-sized metal enclosure with sturdy footswitches and tactile knobs. The control layout is logical and compact: drive / blend / level controls up top, and a four-band EQ beneath. Fit and finish on the Demonfx version feel rugged and roadworthy. Power is standard 9V DC (center negative). If direct output is included on your unit, that adds clear practical value for live and studio use.

Verdict: Good physical build for gigging players — nothing fragile, knobs and switches feel reliable.

Core strengths (selling points — analyzed)

1. Preamp + Distortion in one unit

This pedal combines preamp shaping and a dedicated drive circuit in a single box. That dual role is the main strength: when used as a preamp it can replace a DI/preamp in the chain; when drive is engaged it adds harmonically rich distortion while the EQ still shapes the overall voice. The convenience of both functions in one pedal simplifies a board and reduces cabling/DI complexity.

Value: High — especially for players who want a compact solution for both clean DI tones and distorted bass in one unit.

2. Powerful 4-band EQ

The Bass / Low Mids / Hi Mids / Treble layout gives precise control. The low-mid band is particularly useful for cutting or boosting “boxiness” or adding presence for modern heavy tones. Because the EQ sits after the drive section (or interacts with it depending on your settings), you can sculpt both the character and the articulation of distortion.

Value: Very useful — more flexible than a 3-band EQ and essential when mixing with heavy guitar bands.

3. Blend control (clean + drive mix)

Blend is crucial for keeping fundamental low end while adding grit on top. This pedal’s blend control allows you to retain punch and note definition while dialing in aggressive drive. For live mixes this prevents low-end smear that often happens when players run full distortion without a blend.

Value: High for metal/rock; also excellent for session players who need clean low end in mixes.

4. Direct Output (if present)

A direct out saves a DI box and gives consistent tone to the FOH or interface. It’s a real convenience for front-of-house engineers and for recording — provided the direct out implementation is well-EQ’d and low-noise.

Value: Practical and time-saving for live and studio work.

Tone characteristics (objective observations)

• Clean/preamp mode: Warm, tight low end with clear mids. Works well for slap and fingerstyle when drive is off.

• Drive mode: Aggressive, harmonically rich distortion. Keeps definition when blend is used; at full drive it becomes very scooped and modern-sounding — excellent for djent/metal.

• EQ response: Effective and musical; low mids control resonance and presence, treble adds clarity without biting if not overdone.

• Noise: Expect some noise when gain is high (typical of high-gain bass pedals). Proper gain staging and a compressor can control perceived noise.

Practical use & pairing suggestions

• Placement: Best placed after light overdrives (if used) and compression, but before modulation effects. Suggested chain: Tuner → Compressor → Light OD (if desired) → D7K Ultra → Modulation → DI/Interface.

• Compression: Use a compressor before the pedal for tighter dynamics and less peaky distortion.

• Low-end management: If you want pronounced low-end without mud, use the blend control to keep clean lows and boost harmonics with the drive for presence.

• Recording: Use the Direct Out for a consistent signal into your interface; double-track DI with amp reamping for added character.

• Live preset tips: For heavy styles try Blend ~50–60%, Drive 40–70%, Low Mids +2 dB, Hi Mids ~11 o’clock. For pop/worship keep Drive low or off and use EQ to add clarity.

Weaknesses & things to consider

• Not an exact Darkglass replica: The Demonfx unit recreates the vibe and layout of high-end preamp/distortion pedals, but it is not an official Darkglass product. Expect tonal differences and variation between production batches.

• Noise at high gain: Like many high-gain pedals, it can introduce hiss; use noise suppression or careful gain staging if this is a concern.

• Feature parity: Some original high-end preamps include advanced routing or cab-sim features — these may be missing depending on the version you buy.

Who should buy it?

• Metal and modern rock bassists who want a compact preamp + distortion solution.

• Bassists who gig and need a DI-capable preamp for FOH without carrying an amp.

• Players building a streamlined pedalboard who value blend control and a four-band EQ.

Practical Tips: Using and Pairing This Pedal for the Best Possible Tone

🔥 1. Ideal position on the pedalboard

Recommended placement: near the end of the signal chain, right before modulation or DI.

Suggested order:
Bass → Tuner → Compressor → Light Overdrive (optional) → D7K Ultra → Modulation → DI/Interface

👉 Reason: As a preamp/EQ, the D7K Ultra should shape the final tone.

🔥 2. Pair with a compressor for stable dynamics

Good matches:

• MXR M87

• Boss BC-1X

• Demonfx Compressor

Benefit:
Keeps your tone consistent, especially for slap bass or aggressive picking.

🔥 3. Enhance low-end clarity with a “low-end booster”

Works well with:

• Harmonic Booster

• Standalone EQ pedal

• HPF/LPF filters

Why:
Adds clean harmonic depth without muddying the mix.

🔥 4. Stack a light overdrive before D7K Ultra for thicker drive

Suggested chain:
Bass → Light OD (BD2, OCD, BB Preamp clone) → D7K Ultra

Result:
A fuller, richer, more complex overdrive texture.

🔥 5. Blend clean and drive signals for mix clarity

Recommended metal/rock live setting:

• Blend: 50%

• Drive: 20–40%

• Low Mids: +2 dB

• High Mids: +1 dB

👉 Keeps the bass clear in a band with heavy guitars.

🔥 6. Use the Direct Output for clean, low-noise recordings

Best setup for studio:

Pedalboard → D7K Ultra → Direct Out → Audio Interface

Result:
Punchy, modern bass tone ideal for recording without extra noise.

🔥 7. Suggested EQ presets by genre

🎵 Metal / Hardcore / Djent

• Bass: 1–2 o’clock

• Low Mids: 2 o’clock

• High Mids: 11 o’clock

• Treble: 1 o’clock

• Blend: 50–60%

• Drive: 40–70%

🎵 Pop / Worship / Funk

• Bass: 12 o’clock

• Low Mids: 1 o’clock

• High Mids: 1 o’clock

• Treble: 11 o’clock

• Blend: 40%

• Drive: Off or 10–20%

🎯 Key Takeaways

✔ Turns your pedalboard into a high-quality bass preamp system
✔ Modern, articulate tone suitable for any stage or studio environment
✔ Flexible EQ and blend controls for precise tone shaping
✔ Ideal for all genres—from clean worship tones to heavy metal distortion

Final verdict

The Microtubes D7K Ultra V2 (Demonfx) is a strong, practical option for bassists seeking modern, punchy distortion combined with full preamp tone shaping. It brings excellent flexibility via blend and a detailed EQ section, and the direct out capability makes it a convenient live/recording tool.

Be realistic about noise when running high gain, and remember it’s an interpretation of the Darkglass aesthetic rather than the original model. For players who want a single pedal to handle both DI preamp duties and heavy drive tones, this unit represents a very compelling value.