eumhyangi johgo ttohan mudaedo keo.

이 is the subject marker. It marks 음향 as the thing being described.

• 음향이 좋다 = The sound/acoustics are good
• Here, 좋다 is describing 음향, so 이/가 is natural.

Because 음향 ends in a consonant, the subject particle is 이 rather than 가.

음향 usually refers to sound, audio, or acoustics. In a sentence like this, it often means something like:

• the sound quality
• the acoustics
• the audio setup

So depending on context, it could refer to a concert hall, theater, event venue, etc.

좋고 is the adjective 좋다 in its connecting form.

• 좋다 = to be good
• 좋고 = is good, and ...

The ending -고 links one clause to another, like and in English.

So:

• 음향이 좋고 또한 무대도 커
  = The sound is good, and also the stage is big.

-고 connects two descriptions.

Here it links:

1. 음향이 좋고 = the sound is good
2. 또한 무대도 커 = also, the stage is big

It is one of the most common Korean ways to say and when connecting verbs or adjectives.

또한 means also, in addition, or furthermore.

It adds another point:

• 음향이 좋고 = the sound is good
• 또한 무대도 커 = also, the stage is big

A useful nuance: 또한 sounds a bit more formal or written than everyday 또.

Yes, both contribute an also meaning, but they work differently.

• 또한 is an adverb: also / furthermore
• 도 is a particle attached to a noun: too / also

So in 또한 무대도 커:

• 또한 adds the idea in addition
• 무대도 means the stage too / the stage also

Using both can sound a bit emphatic, like:

• The sound is good, and on top of that, the stage is big too.

It is grammatically fine, though depending on style it can feel slightly stronger or more formal than necessary.

도 means also/too, and it often replaces other particles like 이/가 or 은/는.

So:

• 무대가 커 = the stage is big
• 무대도 커 = the stage is big too / also the stage is big

Even though 가 is not written, the meaning is still clear. You can think of 도 as taking its place here.

커 comes from the adjective 크다, which means to be big.

The sentence is using the casual non-polite present form:

• 크다 → 커

This happens because 크다 combines with -어, and the form becomes 커.

So:

• 무대도 커 = The stage is big too

The sentence is in a casual/plain spoken style.

Compare:

• 커 = casual
• 커요 = polite
• 큽니다 = formal

So the sentence could be changed depending on tone:

• 음향이 좋고 또한 무대도 커요. = polite
• 음향이 좋고 또한 무대도 큽니다. = formal

The original sentence sounds like casual speech or informal written style.

Yes, it is understandable and grammatical. However, depending on context, a native speaker might more commonly say something slightly simpler, such as:

• 음향이 좋고 무대도 커.
• 음향도 좋고 무대도 커.

Why? Because 또한 can sound a little more formal or written than the rest of the sentence, especially with the casual ending 커.

So the original sentence is fine, but stylistically it mixes a somewhat formal word (또한) with a casual ending (커).

Korean often leaves out things that are understood from context.

In English, you might say:

• This venue has good acoustics, and the stage is big too.

In Korean, if everyone already knows what place is being discussed, you can simply say:

• 음향이 좋고 또한 무대도 커.

The listener naturally understands that these are features of the place being talked about.

Yes, that is a very natural translation.

Because the meaning is already given, the important thing to notice is that Korean often expresses this kind of description more compactly than English. The sentence is basically listing two positive qualities:

• good sound/acoustics
• big stage

So The acoustics are good and the stage is big too is an excellent natural rendering.

The difference is in what is being emphasized.

1. 음향이 좋고 또한 무대도 커

This sounds like:

• The sound is good, and also the stage is big.

It presents 음향 first as a statement, then adds another point about the stage.

2. 음향도 좋고 무대도 커

This sounds like:

• The sound is good too, and the stage is big too.

This version more clearly suggests that both are positives being listed in parallel.

So if you want a neat A too, B too structure, 음향도 좋고 무대도 커 is especially common.