As with the glissando, the two main techniques for producing microtonal intonation, apart from the natural tunings of partials, are embouchure and slide adjustment (hardware).
Sounding partials of various harmonic series, the tuba—like brass instruments in general—has a natural capacity for certain microtonal intonations. Natural intervals should be easily accessible for most players, provided they can counteract the years of training spent adjusting the instrument to equal temperament.
As explained in the section on Glissando, embouchure can in most cases be used to alter the base pitch by up to a semitone in either direction. However, range decreases as higher partials become closer together.
Cultivating the muscle memory to immediately find specific microtonal tunings via embouchure takes a great deal of practice. Most often, there will be a “best guess” approximation, followed by a quick adjustment. Again, capacities for speed and accuracy of microtonal intonation will vary from performer to performer. However, the composer should avoid writing virtuosic microtonality to be produced with this technique, unless willing to accept a great deal of inaccuracy.
The adjustment of a slide allows for an across-the-board shift in tuning for all fingerings that connect to the slide in question. Thus, the tubist could play a fast series of quartertones by fingering traditional well-tempered partials, which are detuned by the slide shift.