Tegeler Audio Tube Summing Mixer

Authentic Analogue Console Character Meets Digital Precision

The Tegeler Audio Tube Summing Mixer (TSM) is a premium 40-channel analogue summing engine designed for mixing engineers, mastering professionals, and studio producers who demand the depth, width, and cohesive harmonic glue of a classic analogue console while maintaining a modern digital workflow. Hand-crafted in Berlin, Germany, the TSM combines 32 DB25 inputs and 8 TRS inputs with active NOS tube circuitry and custom output transformers, bridging digital accuracy and vintage analogue warmth.

Active Tube and Transformer Output Architecture
At the core of the TSM is an active output stage built around high-grade NOS 12AU7/ECC82 valves and custom-matched audio transformers. Unlike passive summing boxes that require external preamps to recover lost signal levels, the TSM delivers full line-level output independently. The internal mix bus provides up to +22 dBu of headroom, introducing natural harmonic saturation and gentle transient smoothing while keeping frequencies open, sweet, and three-dimensional.

Stepped Output Attenuation for Total Recall
Traditional analogue consoles often introduce level drift and recall inconsistency due to variable potentiometers. The TSM solves this workflow barrier by utilising a precision 6-stage stepped rotary output switch operating in -3 dB increments (down to -15 dB). This allows engineers to drive stems hard into the tube stage to capture rich harmonic saturation, then attenuate output levels in exact decibel steps for clean A/D converter headroom and 100% accurate session recall.

High-Density 40-Channel Architecture with Flexible Routing
Accommodating large multitrack sessions, the TSM features 40 balanced line inputs split between four 8-channel DB25 connectors (Tascam layout) and eight Neutrik TRS jack inputs. For simplified mono tracking, plugging a mono source into the lower TRS jack of a channel pair automatically routes the signal to both left and right buses, placing it dead-centre in the phantom stereo field. Multiple TSM units can also be cascaded for expanded channel counts or surround setups.

Main features:

• 40 balanced line inputs comprising 32 DB25 channels in Tascam layout and 8 Neutrik TRS channels
• Active tube and transformer output stage powered by dual NOS 12AU7 / ECC82 valves
• Precision stepped output rotary switch with -3 dB attenuator increments for 100% mix recall
• Internal mix bus design providing up to +22 dBu of analogue headroom
• Dual illuminated analogue VU meters for precise master output monitoring
• Automatic phantom-centre signal distribution for mono sources on lower TRS inputs
• Stereo XLR balanced output connections for seamless converter and mix bus integration
• Unit cascading support for expanded track counts and surround sound configurations
• Hand-built construction in Berlin, Germany with internal linear toroidal power supply

Tech Specs:

• Poduct type: Analogue Tube Summing Mixer
• Input Count: 40 Channels (32 DB25, 8 TRS Jack)
• Input Connectors: 4 × DB25 (Sub-D, Tascam layout), 8 × 6.35 mm TRS Jack (Neutrik)
• Output Connectors: 2 × XLR Balanced (Left / Right Stereo Output)
• Active Circuitry: Dual NOS 12AU7 / ECC82 Tubes & Custom Output Transformers
• Mix Bus Headroom: Up to +22 dBu
• Maximum Input Level: +22 dBu
• Maximum Output Level: +24 dBu
• Input Impedance: ≥ 10 kΩ
• Output Impedance: < 600 Ω
• Frequency Response: 20 Hz – 40 kHz (±1.5 dB)
• Dynamic Range: ≥ 110 dB (Unweighted)
• Channel Crosstalk: > 90 dB @ 1 kHz
• Output Level Control: Stepped attenuator (-3 dB increments down to -15 dB)
• Metering: 2 × Backlit Analogue VU Meters
• Power Supply: Internal linear PSU with toroidal transformer (230 V / 115 V)
• Power Consumption: < 25 W (500 mA slow-blow fuse)
• Rack Dimensions: 2U Rackmount (88.1 mm H × 483 mm W × 250 mm D)
• Weight: Approximately 7.5 kg
• Country of Manufacture: Germany (Berlin)
• Discover Tegeler Audio Premium Solutions: https://www.tegeler.com/en-US/TubeSummingMixer