Some collaborations are built around contrast: one musician brings this, the other brings that, and somewhere in the middle they negotiate a musical treaty. Fax and Braulio Lam seem to have taken the more difficult route. After three records and six years of working together, their individual contributions on "Mixed Signals III" have become so thoroughly entangled that trying to separate them would feel slightly impolite. This is not quite a dialogue between electronic musician and guitarist, nor a meeting between machine and wood. It is closer to two people having spent enough time listening to one another that the distinction between who is saying what has ceased to matter.

The history is worth remembering. Fax, the alias of Rubén Alonso Tamayo, has been an important figure in Mexican electronic music for more than two decades, first through Static Discos, the Tijuana label he co-founded, and later through his own Facade Electronics imprint. His catalogue stretches from minimal techno toward increasingly spacious forms of ambient and sound design. Braulio Lam comes from the Tijuana-San Diego border scene and has worked as a guitarist in rock, jazz and electronic contexts since 2013. He describes himself primarily as a guitarist rather than an electronic musician, a distinction that becomes particularly revealing here. "Mixed Signals III" does not use the guitar as a quaint acoustic object placed inside an electronic environment. It lets the guitar alter what the electronic environment can mean.

“Lowside” makes the change immediately apparent. The guitar is unusually exposed, its tone carrying enough warmth and grain to resist being absorbed into the surrounding electronics. But nothing here resembles a conventional acoustic performance. Notes are stretched, repeated, processed and allowed to become part of a larger field in which synth tones and environmental traces appear at carefully judged distances. The music is quiet without being empty. There is always something happening around the edges, although the record has the good manners not to point at every detail with a fluorescent marker.

This is where the third instalment differs subtly from its predecessors. The first "Mixed Signals" had a more grounded physicality, with muted rhythmic impulses and guitar moving through synthetic textures; "Mixed Signals II" opened the frame considerably, favouring field recordings, drones and a more overtly cinematic sense of scale. The new album does not simply reverse that expansion and return home. Instead, it brings the large spaces closer to the body. The horizon has not disappeared. It has simply stopped shouting from several kilometres away.

“Aki” is particularly effective in this respect. Its guitar figures have something almost folk-like about their simplicity, but the surrounding sound refuses to let that simplicity settle into nostalgia. Synthesised tones drift in and out, sometimes reinforcing the guitar's melodic contour, sometimes making it seem as though the melody is being remembered from another room. There is a faint tension between the recognisable and the elusive. You can follow the guitar, but you cannot quite predict where its surroundings will take it.

The title "Mixed Signals" has always been apt, but the ambiguity here is less about confusion than coexistence. Guitar and synthesis frequently occupy different kinds of space without being placed into opposition. A processed tone may behave like an extension of the guitar; a guitar resonance may sound almost electronic. The ear keeps trying to assign responsibility, only to discover that responsibility has apparently been outsourced to a committee of timbre. It is a very efficient way of making collaboration audible without turning collaboration into a spectacle.

“Serifa”, the shortest piece, brings the relationship into especially sharp focus. The guitar and synthesizer seem to move toward one another rather than simply occupying the same arrangement, and the piece acquires a gentle sense of reciprocity. There is melodic material here, but it is never allowed to become a tune in the conventional sense. Instead it becomes a path through which the two sound sources can recognise one another. The restraint is important. A less patient production might have added a beat, enlarged the harmonic field or introduced some dramatic swell to underline the emotional significance. Fax and Lam wisely leave the emotional intelligence in the textures.

The final “400D” is more spacious again, and its title brings an almost photographic association to a record whose cover was also created by Lam. That seems fitting. Lam's background as a photographer is not merely biographical decoration: "Mixed Signals III" often behaves like a sequence of carefully framed images, except that the camera has been replaced by a microphone and the depth of field is determined by reverb, frequency and duration. Sounds appear sharply in the foreground while others remain just beyond focus. The music does not describe a landscape so much as determine how much of one can be seen at any given moment.

There is a particularly appealing quality to the way the album handles silence. It never treats quietness as a grand spiritual statement. Silence is simply another compositional material, allowing one sound to retain its shape before another arrives. Lawrence English's mastering at Negative Space preserves that spaciousness without turning it into glossy audiophile wallpaper. The details remain present, but they are not polished into sterility. There is still dust on the surface, which is exactly where a record like this needs it.

The border between Tijuana and Mexicali, where the two musicians work, inevitably forms part of the album's context, but the music does not need to turn geography into postcard symbolism. Its sense of place is quieter and more convincing. It resides in the particular grain of the guitar, the measured electronic processes, the feeling of distance between sounds and the awareness that two musicians can work across a physical space without making separation itself into a dramatic theme. The border is there as lived geography rather than decorative mythology.

What makes "Mixed Signals III" satisfying as the conclusion to the trilogy is therefore not a grand summation. It is the increased confidence of the relationship. The musicians have reached the point where they can leave more things unresolved because they know exactly how much weight an unresolved sound can carry. “Lowside” establishes the ground, “Aki” lets melody breathe inside it, “Serifa” brings the two voices closest together, and “400D” leaves the frame open again. Four tracks, roughly twenty-six minutes, and not a single unnecessary drum roll announcing the significance of the occasion.

Six years after the first volume, the mixed signals have become remarkably clear about one thing: neither Fax nor Braulio Lam needs to dominate the other. The music works because authorship has become less important than attention. One sound leaves room for another, the other alters it, and the resulting third thing belongs to neither musician completely. Perhaps that is what a successful long-term collaboration eventually becomes: not two voices speaking simultaneously, but a strange new voice neither of them could have produced alone.

The trilogy closes, then, without slamming a door. It simply lets the last resonance remain in the room a little longer than strictly necessary. Human beings are usually in such a hurry to call things finished. These two seem to understand that a good ending is sometimes just the point at which nobody feels compelled to add anything else.