Teknosign Sum Classic tested by RecnMix
RecnMix tested the Teknosign Sum Classic in an episode dedicated to analog summing. Here's what they learned and why it can really matter in the mix.
When a test is initiated independently, the result is worth more. This is what happened with the Teknosign Sum Classic on RecnMix's The Audio Nerd Show. The episode addressed a question that still divides engineers, producers, and mixing enthusiasts: is analog summing really necessary?
To provide a concrete answer, Andy Cappellato and Max Belladonna compared three analog summing amplifiers live. Among them was the Teknosign Sum Classic, alongside two well-known names. The test didn't stop at a quick listen. It demonstrated, in a practical way, what changes when the summing amplifier truly enters the mix workflow.
How the Test Was Conducted
The test was conducted in two distinct phases.
- Phase 1: Comparison on Already Mixed Stems
In the first phase, the team used four pre-mixed stereo stems. They ran the signals through the three summing amplifiers and carefully aligned the levels. They then applied the same final processing to each chain: SSL compression and Pro-L2 limiting under the same operating conditions.
This initial comparison served to observe the behavior of the different summing amplifiers compared to an in-the-box digital summing amplifier. It's a useful step, but not the most revealing.
- Phase 2: Mix Built Directly in the Summing Amp
The second phase offered the most interesting insights. Here, the mix wasn't run through the summing amplifier after the mix was finished. Andy and Max built it with the summing amplifier active from the start.
This changes a lot. The mixer decides on EQ, compression, balance, and space management by listening to the circuit's response. This is why an analog summing amplifier shows its true potential here.
What We Found About the Teknosign Sum Classic
During the review, the Teknosign Sum Classic demonstrated a clearly recognizable sonic personality. Already in the stem comparison, RecnMix noted a more solid low and mid-low range. RecnMix also described the overall response as more compact and coherent.
In the mix built directly in the summing mixer, these impressions became even clearer. During live performance, Andy and Max frequently drew attention to the three-dimensionality of the kick drum and bass. They also found the overall presence of the mix very convincing.
The volume control on each channel was also highly appreciated. This control offers more than just operational convenience. It allows for better management of the amount of signal entering the summing circuit. This allows for more creativity, more control, and greater repeatability in coloration.
This point is important. It clearly explains the difference between a summing mixer used only to output from the DAW and an instrument that truly participates in the mixing process.
Why an analogue summing stage can make all the difference
This episode also has another merit: it explains in simple terms a concept that is often described in overly abstract terms.
An analogue summing stage replicates the point on the mixing console where signals from the various channels converge onto the stereo bus. Moving this stage outside the DAW introduces certain qualities typical of analogue hardware. These include harmonic behaviour, transient response, signal interaction and a different perception of depth.
The advantage, however, really comes to the fore when mixing through the summing mixer. If used only at the end, on a mix that has already been finalised, the result can be more limited.
This is why the Teknosign Sum Classic makes sense within a precise workflow. It should not be viewed as a mere accessory. It can become a real part of the mix bus and the construction of the balance.
Key features of the Teknosign Sum Classic
The Teknosign Sum Classic is a 16-channel stereo analogue mixer designed and manufactured entirely in Italy.
- 16 inputs with independent volume control per channel
- Pan control for each channel with left, right or centre selection
- Extended frequency response from 1 Hz to 150 kHz
- Inputs via dual DB25 connectors
- Balanced XLR outputs
- Stereo auxiliary input for connecting a second summing mixer
- Internal 110–230 V AC power supply
- Aluminium construction and Italian assembly
For those seeking a more compact solution, Teknosign also offers the SAM version of the Box Line series. It is designed for integration into modular rack setups.
Why this test really matters
The value of this test does not depend solely on comparisons with well-known products. What matters most is the context in which it took place.
A public session, based on comparative listening and practical tests, offers more useful insights for those considering a genuine upgrade to their mixing setup.
Those already working in a DAW will recognise a specific limitation: small, flat or two-dimensional mixes. In such cases, an analogue summing mixer can be a practical solution. From this test, the Teknosign Sum Classic emerges with a distinct, recognisable character that is anything but generic.
You can watch the full episode of The Audio Nerd Show dedicated to analogue summing on YouTube. The segment on the Teknosign Sum Classic starts at 1:12:05.
RecnMix also provides the tracks used for the test. It’s an excellent opportunity to try out this approach in your own work environment. This way, you can understand more clearly how much analogue summing can affect your mix.
Watch the episode on YouTube: The Audio Nerd Show – episode dedicated to analogue summing
Discover the Teknosign Sum Classic: Teknosign product page