SPL AUDIO GoldMike Mk2 Dual Channel Microphone and Instrument Preamplifier
Home / SPL AUDIO GoldMike Mk2 Dual Channel Microphone and Instrument Preamplifier
Product Overview
The Flagship Hybrid Front End for Premium Depth and Warmth
The SPL GoldMike Mk2 represents the ultimate evolution of hybrid preamplifier design. While standard tube preamps often suffer from excessive noise or mud, and solid-state designs can sound flat, the GoldMike Mk2 blends the best of both worlds. It pairs a discrete, low-noise Class-A transistor array with an authentic high-voltage vacuum tube stage running on its own dedicated +250V rail. Hand-built in Germany, this 2U rackmount powerhouse acts as an elegant, warm, and highly musical front-end matrix designed to imbue vocals, acoustic groups, and direct-connected instruments with expensive, analog hardware character.
Product Description
Discrete Class-A Solid-State with +250V High-Voltage Tube Stage:
The topology of the GoldMike Mk2 relies on a dual-stage amplification framework. The primary amplification is handled by an ultra-clean, discrete Class-A solid-state stage using matched transistors to preserve extreme transient velocity and high headroom. From there, the signal passes into a high-voltage vacuum tube circuit running on a massive +250V anode supply rail. This true high-voltage setup ensures the tube operates with maximum linear headroom and minimal self-noise, completely avoiding the starved-plate distortion artifacts common in lower-tier equipment.
Three-Stage "Flair" Tube Saturation Control:
Unique to the GoldMike Mk2 is the front-panel Flair switch. This hardware module allows you to select between three distinct tube operating levels (+6 dB, +12 dB, and +18 dB of tube contribution). By increasing the tube's role in the gain structure, you introduce progressive amounts of beautiful even-order harmonics. This rounds out low-end bass fundamentals, opens up the midrange body, and injects a silky, airy sparkle into high frequencies—perfect for tailoring vocal presence to match a dense mix.
Premium Instrument DI and Built-In Analog Peak Limiter:
Discrete Hi-Z Inputs: The front panel houses low-noise, high-impedance ($1\text{ M}\Omega$) instrument inputs. Operating through dedicated Class-A circuits, they capture electric guitars, active basses, and synths without tone-sucking loading effects.
Analog Peak Limiter: A built-in hardware protection limiter with a dedicated threshold safeguards downstream A/D converters from clipping. It acts with microsecond speed to catch sudden transient overloads while adding a cohesive, tape-style glue to the dynamics.
Flexible Input/Output Routing Options:
The rear panel provides extensive connectivity, featuring independent Insert Send and Return jacks per channel. This lets you loop in external hardware compressors or EQs cleanly right after the preamplifier stage. The main outputs are fully mirrored across balanced XLR and unbalanced 1/4" jacks, allowing you to feed a primary recording interface and a backup monitor controller simultaneously with no signal loss.
Key Features
TRUE HYBRID CLASS-A / TUBE DESIGN: Combines a transparent discrete Class-A solid-state front end with an authentic high-voltage vacuum tube secondary stage.
+250V TUBE ANODE POWER: Runs on an elite +250V rail system to guarantee linear analog headroom and rich harmonic character without starved-plate noise.
3-STAGE FLAIR SATURATION SWITCH: Front-panel selector modifies tube contribution (+6 dB, +12 dB, +18 dB) to dial in customized analog warmth and presence.
BUILT-IN HARDWARE PEAK LIMITER: Smart, ultra-fast analog limiter guards digital audio converters against overloads while gluing dynamic spikes.
DISCRETE 1 M$\Omega$ INSTRUMENT DI: Front-panel high-impedance inputs optimize tracking for active/passive instruments with zero loading loss.
DEDICATED REAR INSERT LOOPS: Balanced insert points per channel make it easy to patch in external hardware processors before the output.
VINTAGE VU METERING WITH PAD: Backlit analog VU meters provide accurate level monitoring with a switchable level reduction pad for hot signals.
MADE IN GERMANY: Proudly developed, hand-assembled, and quality-tested in Germany using premium through-hole components.
Technical Specifications
Line / Insert Connections
Feature
Specification
I/O Ports
XLR (Balanced) & 1/4" Jack (Unbalanced)
Maximum Input Gain
23 dBu
Input Impedance
10 dBu
Maximum Output Gain (Balanced)
26.8 dBu
Maximum Output Gain (Unbalanced)
21.5 dBu
Output Impedance
50 $\Omega$
Common Mode Rejection (1 kHz, 0 dBu)
70 dB
Frequency Range (-3 dB)
10 Hz – 90 kHz
THD + N (0 dBu, Line Unity, Tube +6 dB, 10 Hz–22 kHz)
0.04 %
Noise (A-weighted, 600 $\Omega$)
-88.5 dBu
Dynamic Range
110 dB
Microphone Preamplifier Stage
Feature
Specification
Maximum Input Gain (Mic)
7 dBu
Maximum Input Gain (Mic with PAD)
28 dBu
Input Impedance (Mic)
2.8 k$\Omega$
CMRR (1 kHz)
75 dB
Frequency Range (Tube Gain +6 dB, -3 dB)
10 Hz – 93 kHz
Frequency Range (Tube Gain +12 dB, -3 dB)
10 Hz – 61 kHz
Frequency Range (Tube Gain +18 dB, -3 dB)
10 Hz – 34 kHz
THD + N (1 kHz, 30 dBu Gain)
0.016 %
Noise (A-weighted, 150 $\Omega$, 30 dB Gain)
-91.2 dBu
E.I.N. (Equivalent Input Noise)
-128 dBu
Dynamic Range
110 dB
Instrument Preamplifier Stage
Feature
Specification
Maximum Input Gain (Instrument)
7 dBu
Maximum Input Gain (Instrument with PAD)
14 dBu
Input Impedance (Instrument)
1 M$\Omega$
Frequency Range (Tube Gain +6 dB, 600 $\Omega$, -3 dB)
10 Hz – 68 kHz
Frequency Range (Tube Gain +12 dB, 600 $\Omega$, -3 dB)
10 Hz – 51 kHz
Frequency Range (Tube Gain +18 dB, 600 $\Omega$, -3 dB)
10 Hz – 35 kHz
THD + N (Tube Gain +6 dB, 10 Hz – 22 kHz)
0.05 %
Noise (A-weighted)
-95.5 dBu
Dynamic Range
105 dB
Power & Hardware Footprint
Feature
Specification
Power Supply Type
Internal Linear Power Supply with Toroidal Transformer
Operating Voltage (Analog Audio)
$\pm$18 V
Operating Voltage (Relays & LEDs)
+12 V
Tube Anode Voltage
+250 V
Tube Heating Voltage
+12.6 V
Phantom Power Supply
+48 V
Mains Voltage (Selectable)
230 V AC / 50 Hz | 115 V AC / 60 Hz
Fuses
T 315 mA (for 230 V) | T 630 mA (for 115 V)
Power Consumption
Max. 25 W
Dimensions (W x H x D)
482 x 88 x 210 mm (19 x 3.46 x 8.23 inches)
Unit Weight
4.1 kg (9.04 lbs)
Shipping Weight (Incl. Packaging)
6.5 kg (14.33 lbs)
Reference Ground Level
0 dBu = 0.775V (Specifications subject to change without notice)
What’s Included in the Box
1 x SPL AUDIO GoldMike Mk2 Dual-Channel Hybrid Preamplifier Unit
1 x Standard AC Power Connectivity Cable (IEC)
1 x Set of Adhesive Rubber Desktop Surface Isolation Feet
1 x Official SPL Studio Series Manual & High-Voltage Tube Calibration Guide
