Στην περιοδεία, το συγκρότημα έχει δυνατά φωνητικά.

Στην is the contracted form of σε + την.

• σε = in, on, at, to
• την = the for a feminine singular noun in the accusative

So στην περιοδεία means something like on the tour, during the tour, or in the tour context, depending on the exact translation being shown.

Greek very often combines σε with the definite article:

• σε + τον = στον
• σε + τη(ν) = στη(ν)
• σε + το = στο

After the preposition σε, Greek normally uses the accusative case.

So the noun περιοδεία appears here as:

• nominative: η περιοδεία
• accusative: την περιοδεία

That is why you get στην περιοδεία and not η περιοδεία.

Even though English often says on tour, Greek uses its own structure, and this one literally looks more like in/on the tour.

Yes. Both can exist, but the nuance is a little different.

• σε περιοδεία often means on tour in a more general sense
• στην περιοδεία can sound more like on the tour or during the tour, referring to a specific tour

So the sentence as written points more naturally to a particular tour, not just touring in general.

Yes. συγκρότημα is a neuter noun, and it means band or group.

That is why the article is το:

• το συγκρότημα = the band

In this sentence, το συγκρότημα is the subject.

Έχει is the 3rd person singular present tense of έχω, which means to have.

So:

• έχω = I have
• έχεις = you have
• έχει = he/she/it has

Because το συγκρότημα is singular, the verb is also singular: έχει.

Because the verb agrees with the subject, not with the noun that comes later.

Here:

• subject: το συγκρότημα = singular
• verb: έχει = singular
• object/thing possessed: δυνατά φωνητικά = plural

So the structure is basically:

The band + has + strong vocals

The fact that vocals is plural does not change the verb.

Because δυνατά has to agree with φωνητικά.

The noun φωνητικά is neuter plural, so the adjective must also be neuter plural.

The adjective δυνατός changes like this:

• masculine singular: δυνατός
• feminine singular: δυνατή
• neuter singular: δυνατό
• neuter plural: δυνατά

So:

• δυνατά φωνητικά = strong/powerful vocals

Here it is an adjective.

That is because it is describing the noun φωνητικά and agrees with it in form.

Greek also has the adverb δυνατά, meaning loudly or strongly, so learners often notice the same form and get confused. But in this sentence it is not an adverb. It is part of the noun phrase:

δυνατά φωνητικά = powerful vocals

In music-related language, Greek often uses φωνητικά in the plural to mean vocals, vocal parts, or the vocal performance.

This is actually similar to English, where we often say the vocals rather than the vocal.

So δυνατά φωνητικά is a natural way to say that the band has strong or powerful vocal performance.

It can suggest both, depending on context, but powerful vocals is usually the better interpretation.

The adjective δυνατός basically means strong, powerful, or sometimes loud. With singing or music, it often describes vocal strength, force, or impact, not just volume.

So in a sentence about a band, powerful vocals is usually the most natural English meaning.

Yes, Greek word order is fairly flexible.

Putting Στην περιοδεία first gives it emphasis as the setting or context:

• Στην περιοδεία, το συγκρότημα έχει δυνατά φωνητικά.

This feels like:

• On the tour, the band has powerful vocals
• During the tour, the band has powerful vocals

You could also move it later:

• Το συγκρότημα έχει δυνατά φωνητικά στην περιοδεία.

That is still understandable, but the original order highlights the tour context first. The comma helps mark that introductory phrase.