The Reference in DAW Analog Summing



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The Original Summing Solution that Ignited the Out-Of-Box Revolution.

Born out of real-world necessity, this tool, the first of its kind, was created to bring back the analog sound-quality, feel and headroom that were missing from the digital mixing environment, while maintaining the fast DAW workflow, editing and recall capabilities that we all depend on.

Through cutting-edge analog audio circuit design the 2-Bus allows the full potential of your studio to be realized–audibly, in terms of sound quality, spatial detail and headroom–and ergonomically in terms of outboard equipment integration in the mix process.  Designed and built with the highest quality components and a no-compromise attitude, this pristine audio path delivers nuance, depth and clarity to your mix without any added coloration, and thus allows the true nature of your recorded tracks and outboard gear to shine.

Searching for punch? Extended soundstage? Definition? Headroom? The Dangerous 2-Bus 16X2 summing device puts that all back  into a lifeless mix. Much like traditional vintage consoles brought together multiple channels of audio, the 2-Bus receives 16 analog outputs from any DAW interface and combines them to stereo. This is its sole purpose and it performs more transparently and musically than any other solution.

  • Massive Punch and Detail
  • Clear Stereo Imaging
  • Incredible Headroom
  • Effortless Outboard Gear Integration
  • The Top Choice of Mix Engineers Worldwide

True summing devices have no individual volume controls, pan pots or aux sends. Those functions are performed by the recording software to leverage automation and recall on demand. Furthermore, running your audio through unneccesary electronics lowers performance.

The measure of a successful mix is consistency: will it translate across multiple mediums like the radio, an iPod, home hi-fi, a car stereo… Therefore, a summing solution must be transparent, yet musical to deliver. Only if and when color is desired, then outboard may be called upon for this purpose.

The Dangerous Music 2-Bus leverages decades of collective experience from the world’s premier mix engineers to guarantee results.

  • Unsurpassed Sonic Performance
  • Stepped Attenuator Volume Control
  • Custom Built Linear Power Supply
  • Fully Linkable with 2-Bus, 2-Bus LT and D-Box
  • Hand Assembled in the USA

You will hear the difference.

Frequency Response:
1 Hz-100 kHz within 0.1 dB

Total Harmonic Distortion:
0.0045% +4 dBu input level
0.0008% +22 dBu input level

Intermodulation Distortion: 
0.0055% +4 dBu input level
0.0015% +22 dBu input level

> 101 dBu

Noise floor:
<-83 dBu total energy in audio band

Max level:
+28 dBu

Nominal operating level:
+4 dBu (1.228 volts)

Input impedance: 
25kohm balanced

Output impedance: 
50 ohms balanced (600 ohm drive capable)

Gain accuracy: 
>0.02 dB @ 1 kHz for any gain setting

Power consumption: 
30 watts

Warranty: Free 2 year extended warranty with online registration.

Standard warranty: 90 days parts and labor, subject to inspection. Does not include damage incurred through abusive operation or modifications/attempted repair by unauthorized technicians.

Choosing Your Summing Amp:

Since the creation of the Dangerous 2-Bus many manufacturers have released “summing box” products. Choosing one can be confusing, but if you ask 2 questions it becomes easy.

1.  Is it really a summing amplifier, or is it a line mixer?

A true summing box designed to be a back-end for a DAW mixer will be “fixed gain and fixed pan,” because the fader and pan controls are in the DAW software mixer. You do not want to repeat these functions in the hardware domain because a) you lose your recall capabilities and b) you are running your audio through unnecessary electronics which will degrade the sound.

If it has pan pots and/or level controls on it, it is a line mixer, not a summing mixer, despite what the front panel might say. A line mixer is perfect if you need to sub-mix keyboards or a bunch of mic preamps to stereo, but is not the best option when mixing a track from your DAW.


2.  Do I want  a clean or colored signal path for my mixing?

The short answer is you want options. Many manufacturers have a signature tonal coloration to their sound, incorporating components like transformers or tubes into the design. These components can sometimes shape the sound in a pleasing way, but you are stuck with that sound for everything you do. We chose to make the tone and color optional with the 2-Bus+ by designing three original analog color circuits that can be selected and adjusted as you need them. Suppose the transformer is great on one song but not right on another – you can simply disengage it with the press of a single button. Or suppose you like the harmonic stimulation, but want less of it. Other summing amps do not have this option; they hold you hostage to a single sound.

A true mastering-style summing amp will let all of what you recorded come through into a clean, high-headroom environment for the summing process. We at Dangerous have a deep background in designing and building mastering consoles and monitor controllers. With our approach to summing you can insert color where, when and how you choose with the onboard processors in the 2-Bus+, or with outboard gear and plugins. All options remain open, the best of all worlds.


A note on passive summing:

There are two types of passive summing devices: powered and non-powered. Non-powered summing amps simply employ a resistor network feeding a pair of busses. This process by its nature loses a considerable amount of level, requiring a high-gain amplifier (microphone preamplifier) to bring it back up to usable line level. Non-powered boxes require the user to insert a separate outboard mic pre for this makeup gain.

Other products have the amplifier built in, appearing on the outside like an active summing device but in fact employ the same non-powered summing as described above.  You can often tell when non-powered summing is being used by a high input channel count (32 or 48 inputs) because the parts cost only pennies, as opposed to having expensive active receiver amplifiers on every input.

We have found through years of experience and testing that this non-powered approach is not the ideal way to handle this task, and that an active design using balanced receiver amplifiers, summing op-amps and line drivers yields the most exceptional performance.

Not having an active balanced design creates several potential problems:

-A balanced receiver provides common mode rejection (CMR) while a passive resistor network does not. Good CMR is key to low noise performance.
-A balanced receiver allows isolation of the D/A converter’s ground from the audio ground of the summing amp – passive does not.  This could lead to poor crosstalk rejection, which means poor imaging.
-Active design also allows for a local ground reference for the inputs, which is the same ground reference as the summing op-amp. All these things contribute to a clean, quiet, low-distortion device that is stable.

There are no reviews yet.

Check out our 2-BUS Reviews HERE


  • Thom Monahan

    TapeOp Magazine

    “[The Paralimiter] results in a beautiful, addicting backdrop of detail that doesn’t suffer from the disappointing wobble and flutter that normally corrupts low end in a mix that’s subject to heavy FET limiting.”

  • Jerry Harrison


    “For the last five years, ET and I have been using the 2-BUS for all of our mixes at my studio.”

  • Chris Tabron


    “The harmonic and transformer flavors are great options to have and the parallel limiter is a genius idea.”

  • Sammy Merendino

    Producer/Mix Engineer

    “The 2-BUS has made a huge difference. My mixes sound the way I want: really big, wide, lots of clarity, low end punch & detail.”

  • Chris Blackwell


    “Plugged it in to my system along with my old 2-BUS and Dangerous MONITOR ST and wow … it’s fantastic! Bags of air and space around the mix.”

  • Jacquire King

    Producer/Mix Engineer

    “The 2-BUS is the sonic equivalent of a large format analog console.”

  • Horace Ward

    FOH Engineer

    “I don’t understand how the 2-BUS has been in the studio for so long, but hasn’t gotten to live shows- the sound is unbelievable.”

  • Gina Fant-Saez

    Mix Engineer

    “The 2-BUS mixes… were simply cleaner and warmer than the SSL or in-the-box mixing… I just don’t miss my console.”

  • Jeff Juliano

    Mix Engineer

    “I was using another brand of summing amp and thought I was happy with it, but as soon as I plugged in the 2-BUS I was floored.”

  • Dirty South


    “The 2-BUS is amazing, it adds so much space and clarity to the mixes.”

  • Submit a testimonial here

Why Use an Analog Summing Mixer? | Audio Engineer Ryan West