During the 1950's, "Tumpa!" was one of Yma's most popular pieces and was invariably singled out for mention in reviews.  Pure program music, it is "..a wordless study in realism, where the voice takes on the character of the things it describes."  (Maurice Leonard, Records and Recording)  It is unfortunate that by 1953, the song had been re-arranged; diluted of its exotic flavor and become a weak-kneed dance number.  By the 1960's Russian tour it had been further diluted and bore even less resemblance to the original.  Even in this present, original program-music format, it strongly resembles the Ch-cha-cha.  But here at least, it is still heavily exotic - not only in the odd juxtaposition of musical and singing styles, but also the wonderful, colorful orchestration.

This is the first example of Yma's "growl."  It is also one of the pieces Les Baxter found so maddening in trying to get Yma to sing the same way twice.  Because of these problems, and the massive editing that followed, the rhythmic structure of the song is unbalanced with unintentional, uneven measures.  None the less, taken on its own, this recording is a perfected gem of singing over three full octaves.

Like "Ataypura" (High Andes), "Tumpa!" is in sections.  Section A is an introductory recitative.  Subtlety is discarded for deliberate shock tactics as Yma furiously growls deep in the chest register.  The effect is as startling as the height which Yma takes her resonant growl - to A in the staff.  Not only can she sustain the growl for these phrases, but she has the technical freedom to indulge in Jazz-like ornaments which she ripples through.  She is also able to effortlessly switch from growled tones to more normal, belted chest voice.

For this effect, Yma growels deep in her throat and vibrates the throat tissues.  There is a secret to her success with this effect.  After each growled phrase that lies dangerously high, Yma uses a descending glissando figure.  This simple figure allows the larynx and muscles to relax naturally after the tension necessary for such a vocal trick.  The glissando is a releasing action that allows Yma to quickly relax and re-set her voice in a more normal position, ready for the next bit of singing.  Thus, despite the risk involved in such a gutteral and percusive effect, by using the simple glissando she is assured of regaining the necessary, natural relaxation of the larynx.  Because of this no damage was ever inflicted to her voice despite the strenuousness of the effect.

Section B is sung in a well-rounded, mixed chest register which Yma introduces with a wonderful passage of syncopation.  Rhythm is of prime importance in this piece and Yma's intimate manner of leaning on and caressing certain beats and notes speaks of an instinctive command of rhythmic and tonal liberties.  There are some unique vocal colorations and accents, including the rapid oscillation of her vibrato on the final note of this section (a low F#) which sounds like a smoky trill.  She does this by keeping her mouth almost closed while increasing the vibrato.

Section C is the depiction of the erupting of the volcano; her voice emulating its eruption through three octaves.  The beginning of this section brings Yma well into the middle register where the voice is clean, clear and excellently focussed.  Subtle rhythmical leanings and colors abound in this part and a loving manner of shaping the phrases born of instinct.  After the main melody Yma treats the listener to one of the most glorious vocal ascents ever recorded.  Within five short measures, Yma rises from the low, contralto F# to the coloratura soprano F#, three-octaves above.  Aside from the height Yma reaches, the remarkable thing about this passage is that throughout the three octaves, not one note is unattractive or loses its focus or sheen.  The poise of Yma's singing belies the fact that this had to be pieced together.  That is why astute listeners will notice the irregular measures.  Whether it was spliced together or not, the notes are real and the climactic high F# is sustained with surprising ease, beauty and vocal intensity.

The second half of "Tumpa!" offers a vocal depiction of frightened animals and birds.  It is here that Yma offers more examples of her pecked-at, bird-like high staccati - similar to those in "Ataypura" (High Andes) The tessitura holds no fear for the singer who rapidly tosses off high Es and F#s with great force and abandon.  Contrasting the elaborate high coloratura are the many effects introduced octaves lower.  These include various jazz-based effects, quarter-tones, open chest-voice calls, syllables like "chum! chum!" and "Wa-ba-ba-ba-ba," grace note approaches, and intentional register breaks.  The song ends abruptly with another call done in vibrant chest voice.