Learn Hardcore Russian: После песни из кулис выходит режиссёр, и начинаются аплодисменты. - After the song, the director comes out from the wings, and the applause begins.

Кулисы are the side parts of a theatre stage: the wings and side curtains that hide actors and props from the audience. You can think of them as “the wings/backstage area (at the sides of the stage)”.

Grammatically:

Singular: кулиса (rare, mostly technical)
Nominative plural: кулисы
Genitive plural: кулис

The preposition из (“from, out of”) takes the genitive case, so:

из кулис = “from/out of the wings (backstage area)”

The noun is in genitive plural (кулис), even though in English we often say just “from backstage” in the singular.

Why is it из кулис and not из-за кулис? What’s the difference?

Both are possible, but they have slightly different nuances:

из кулис – literally “out of the wings/backstage”. Neutral: he comes from that area.
из-за кулис – “from behind the wings/curtains”. It emphasizes that he was hidden behind something and now appears from behind it.

In many contexts, especially in descriptions or stage directions, из кулис is the simple, default choice. Из-за кулис adds more visual emphasis on emerging from behind a barrier.

Why does the verb come first in из кулис выходит режиссёр? Can I say из кулис режиссёр выходит or режиссёр выходит из кулис?

Russian word order is relatively flexible, and all of these are grammatically correct:

Из кулис выходит режиссёр.
Из кулис режиссёр выходит.
Режиссёр выходит из кулис.

The choice affects what is emphasized:

Из кулис выходит режиссёр.
Neutral for narration. The important new information is режиссёр – who comes out.
Режиссёр выходит из кулис.
Here режиссёр is placed first and becomes the topic; we’re talking about the director and what he does.

In the original, starting with из кулис sets the scene/location first, then introduces the new element: режиссёр.

What tense and aspect is выходит, and why not вышел or выйдет?

Выходит is:

Present tense
Imperfective aspect
Third person singular of выходить (“to go out, to come out”)

In this sentence, Russian is using the “narrative” or “dramatic” present: describing events (like stage directions or a typical sequence) in the present tense to make them vivid:

“After the song, the director comes out from the wings, and the applause begins.”

Alternatives:

После песни из кулис вышел режиссёр… – прошедшее время (past): “After the song, the director came out…”
После песни из кулис выйдет режиссёр… – будущее время (future perfective): “After the song, the director will come out…”

So выходит fits a neutral description of what (typically) happens or is happening “on stage” right now, not a specific past or predicted future event.

Can we change the word order to После песни режиссёр выходит из кулис? Does that change the meaning?

Yes, it’s correct:

После песни режиссёр выходит из кулис, и начинаются аплодисменты.

The basic meaning is the same. The differences are in emphasis:

Original: После песни из кулис выходит режиссёр…
Focus on: from the wings someone comes out – it turns out to be the director.
Alternative: После песни режиссёр выходит из кулис…
Focus on: the director and what he does after the song.

Both are natural; choice depends on what you want to foreground in the narrative (place vs. person).

Why is there a comma before и in ..., и начинаются аплодисменты?

Because we have two separate clauses with their own subjects and predicates:

(из кулис) выходит режиссёр – subject: режиссёр, verb: выходит
начинаются аплодисменты – subject: аплодисменты, verb: начинаются

In Russian, when и joins two independent clauses like this, a comma is usually required:

Он вышел на сцену, и зал замолчал.

If the clauses shared the same subject and were very closely connected, the comma might be omitted, but here the subjects are different, so the comma is standard and expected.

Why is аплодисменты plural, and why does the verb начинаются agree in the plural?

Аплодисменты (“applause”) is a plural-only noun in Russian (pluralia tantum). It exists almost exclusively in the plural form:

Nominative plural: аплодисменты
There is no common everyday singular meaning “an applause”.

Because the subject is grammatically plural, the verb must also be plural:

аплодисменты начинаются – “the applause begins”
аплодисменты громко звучат – “the applause is loud”

Using начинается аплодисменты would be incorrect, because of disagreement in number.

Can I ever use the singular аплодисмент?

The singular аплодисмент does exist, but it is:

Rare
Stylistically marked (often written, formal, or joking)

It normally refers to a single instance or unit of applause (a clap, a round, or in counting):

Один аплодисмент в его адрес. – “One ‘applause’ in his direction.” (joking/stylistic)
Пять аплодисментов – as a humorous “score” or label.

For normal everyday Russian, for “applause” as a collective phenomenon, you use аплодисменты (plural) only.

Is there any difference between начинаются аплодисменты and аплодисменты начинаются?

Both are grammatically correct and mean “the applause begins/starts”. The difference is in word order and emphasis:

Начинаются аплодисменты.
Emphasis on the beginning itself: what is happening now? The starting is key, and what starts is then specified.
Аплодисменты начинаются.
Emphasis on the applause as the topic: we’re talking about the applause, and the new information is that it is starting.

In many contexts they are interchangeable; the first form is a bit more “stage-direction-like” and dynamic.

What does the reflexive ending -ся in начинаются do here?

Начинаются comes from the reflexive verb начинаться:

начинать (что?) – to begin something (transitive)
- они начинают песню – they begin the song
начинаться (что?) – to begin (by itself) (intransitive, reflexive)
- песня начинается – the song begins
- аплодисменты начинаются – the applause begins

The -ся (or -сь after a vowel) in Russian often:

Makes a verb reflexive (“wash oneself” – мыться)
Or makes it intransitive/passive-like, as here: “to begin” without saying who is starting it.

So начинаются аплодисменты literally is “the applause begins (itself)”, which in English we just say as “the applause begins / starts”.

Why doesn’t the Russian sentence use words like “the” (the song, the director, the applause)? How do we know they’re definite?

Russian has no articles (no equivalents of “a/an” or “the”). Definite vs. indefinite meaning is determined by:

Context
Word order
Sometimes by additional words (like этот, тот, какой‑то, etc.)

In this sentence, it’s obviously about:

the song that has just been performed,
the director of this show,
the applause from the audience.

A Russian speaker automatically reads it as definite because of the situation being described. If you needed to make it very explicit, you could add demonstratives:

После этой песни из кулис выходит режиссёр, и начинаются аплодисменты.
“After this song the director comes out from the wings, and the applause begins.”

How do you pronounce these key words, and where is the stress?

Approximate stress positions (stressed syllable in CAPS):

пЕсни – PYES-nee (song – gen. sg.)
кулИс – koo-LEES (gen. pl. of кулисы)
режиссЁр – ree-zhee-SYOR
выхОдит – vy-HO-dit
начинАются – na-chee-NÁ-yuts-ya
аплодисмЕнты – ap-la-dees-MYEN-ty

Correct stress is important in Russian; moving the stress can make a word sound unnatural or even resemble a different word.

Does режиссёр mean a theatre director, a film director, or something else?

Режиссёр is a general word for a director in the sense of someone who stages or directs a performance or production:

Theatre director
Film director
TV director
Sometimes the director of a concert/show

In this particular sentence, because we’re talking about a song, wings (кулисы), and applause, the context strongly suggests a theatre or stage director coming out onto the stage.