Does a small tsu double all consonants?


In several sources it's mentioned that a SMALL TSU doubles consonants. My
problem is, some websites give almost identical examples with:

っ/ッ + (S, T, C, K, G, B, P)

But what about the others?:

っ/ッ + (M, N, V, W ...)

When I use some online converter (Kana>Romaji), they double all of them.

So, does a SMALL TSU double all consonants or not? And if not, in which cases?




A small tsu (sokuon) geminates (doubles) the following consonant. In native
vocabulary, only unvoiced consonants can be geminated. This includes the さ, た,
か, and ぱ rows. A double n as in おんな is not really pronounced the same way as
＊おっな would be if it were a word.

In loanwords that require gemination of other consonants, N tends to use ン, M
uses ン or ム, W uses ウ, and others use the -u form of their row. Some examples
are:

  * homemade → ホームメード
  * comma → コンマ
  * whistleblower → ホイッスルブロウワー
  * role-playing game → ロウルプレイングゲーム

Some loanwords do use the sokuon where native words would not, such as:

  * big → ビッグ
  * badge → バッジ

The important thing is that these are all loanwords. You generally won't see
such examples written in hiragana, though the sokuon is used the same way in
either writing system.

You may also see the small tsu at the end of a word or sentence. There it
represents a glottal stop, an abrupt ending.




A small tsu (sokuon) geminates (doubles) the following consonant. In native
vocabulary, only unvoiced consonants can be geminated. This includes the さ, た,
か, and ぱ rows. A double n as in おんな is not really pronounced the same way as
＊おっな would be if it were a word.

In loanwords that require gemination of other consonants, N tends to use ン, M
uses ン or ム, W uses ウ, and others use the -u form of their row. Some examples
are:

  * homemade → ホームメード
  * comma → コンマ
  * whistleblower → ホイッスルブロウワー
  * role-playing game → ロウルプレイングゲーム

Some loanwords do use the sokuon where native words would not, such as:

  * big → ビッグ
  * badge → バッジ

The important thing is that these are all loanwords. You generally won't see
such examples written in hiragana, though the sokuon is used the same way in
either writing system.

You may also see the small tsu at the end of a word or sentence. There it
represents a glottal stop, an abrupt ending.

