Yom Teruah
Rosh Hashanah is described as a "day of Teruah-blasts" (Numbers 29:1) What are these Teruah-blasts of the shofar? What is their connection to Rosh Hashanah and the High Holiday theme of repentance and return?
The Talmud (Rosh Hashanah 34a) relates that there is a longstanding uncertainty as to the exact nature of the Teruah-blast. Some say it is "genuchei ganach," a groaning or moaning. Therefore, the blasts should be heavier, longer sounds called Shevarim, like the sobs of one pained by remorse and regret. 
What does it matter whether the shofar sounds like groans or howls?


What does it matter whether the shofar sounds like groans or howls?

Others, however, say that the Teruah is "yelulei yalil," trembling cries and wails. This opinion holds that the blasts should be short, staccato bursts, like the uncontrolled howling of a person in extreme distress and grief.
What does it matter whether the shofar sounds like groans or howls?
Stimulus for Change
When we look at people who have undergone great transformations, we find two basic patterns. For some people, change is instigated by thought-out processes of logic and reason. Intellectually, they realize that something is seriously amiss in their lives and they strive to correct it. For others, the inducement to change comes from the heart. They are moved by a deep emotional sense that they have abandoned the path that their heart desires.
We might ask which stimulus is truly fundamental to the teshuvah process. Which path is more successful in gaining and maintaining spiritual growth - through the mind or through the heart?
This question is precisely the doubt regarding the sound of the Teruah. The shofar-blasts are a wake-up call for change and return. As Maimonides wrote in Hilchot Teshuvah (3:4): "It is as if the shofar is calling out to us: Wake up sleepers from your slumber! Examine your ways and repent and remember your Creator."
Perhaps the shofar blasts should bring to mind the laments of the introspective individual who has reached the conclusion that his path is false. The shofar is sounding the "genuchei ganach," the groans of one whose assessments have lead him to the unavoidable realization that he has missed the mark in his life and goals. Or perhaps the shofar blasts are meant to mirror the emotional outburst of "yelulei yalil," the terrible cries of pain and anguish of one distraught by a torrent of emotions at losing his way.
Combining Mind and Heart
There is, however, a third possibility. There is an ancient custom that the shofar blasts are a fusion of "genuchei ganach" and "yelulei yalil." This opinion holds that one should blow Shevarim-Teruah, combining groans and uncontrollable weeping.
This custom reflects the most complete form of teshuvah, one 
Perhaps the shofar blasts should bring to mind the laments of the introspective individual.
that incorporates both the intellectual and emotional realms. One begins with an intellectual realization that all is not well, that reparations must be made. This awareness develops a sense of remorse so strong and vivid that it awakens the most powerful emotions. Maimonides similarly described the teshuvah process as progressing from an intellectual decision to emotional remorse: "The sinner abandons the sin, removing it from his thoughts and resolving not to repeat it.... Then he regrets the past." (Hilchot Teshuva 2:2)

Perhaps the shofar blasts should bring to mind the laments of the introspective individual.
that incorporates both the intellectual and emotional realms. One begins with an intellectual realization that all is not well, that reparations must be made. This awareness develops a sense of remorse so strong and vivid that it awakens the most powerful emotions. Maimonides similarly described the teshuvah process as progressing from an intellectual decision to emotional remorse: "The sinner abandons the sin, removing it from his thoughts and resolving not to repeat it.... Then he regrets the past." (Hilchot Teshuva 2:2) This is the most effective form of teshuvah, as it utilizes the strengths of both faculties, the emotions and the intellect. The advantage of emotions over cold logic is their ability to make a profound impression on the soul. Changes based on emotions without a reasoned foundation, however, may not be able to sustain themselves in the long run.
The psalmist exclaimed, "Fortunate are the people who know the Teruah-blast." (Psalms 89:16) What is so wonderful about recognizing the blasts of the shofar? Rather, the verse means this: when we understand the true power of the Teruah - when we know how to utilize both of its forms, the genuchei of the mind as well as the yelulei of the heart - then we can base our teshuvah on the solid foundation of logic and emotions together. With such Teruah-blasts - "they will walk in the light of Your countenance." (ibid.) Then, our path is certain to continue in God's light.
[Adapted from Olat Re'iyah vol. II pp. 328-329]