I think "speak" is better here. I associate "talk" more with communication than the physical act of producing words.

@@ -19,2 +19,2 @@
-<s_inf>usu. in negative</s_inf>
-<gloss>to be able to talk</gloss>
+<s_inf>usu. in the negative</s_inf>
+<gloss>to be able to speak</gloss>

we generally avoid these two for one glosses

@@ -13 +13,2 @@
-<gloss>to emit a sound (voice)</gloss>
+<gloss>to emit a voice</gloss>
+<gloss>to emit a sound</gloss>

@@ -13 +13 @@
-<gloss>to emit a (voice) sound</gloss>
+<gloss>to emit a sound (voice)</gloss>

GG5 - many examples, mostly from 声が出ない
Tanaka: 3 sentences, also from 声が出ない

I think it's both common enough and slightly idiomatic enough to be worth recording. I'm suggesting a sense split to highlight the more common usage. If approved I'll index those sentences to sense 2.

@@ -12,0 +13,6 @@
+<gloss>to emit a (voice) sound</gloss>
+</sense>
+<sense>
+<pos>&exp;</pos>
+<pos>&v1;</pos>
+<s_inf>usu. in negative</s_inf>

"驚きのあまり、声が出てしまった"
"鯛の刺身が美味しすぎて声が出た"
"お腹から声を出せば、高い声が出る"

I'm not sure this needs to be an entry.
While "声が出ない" usually translates to "to be unable to speak", the positive form is more broad in meaning. It just means "to emit a voice" (like 声を出す except that it occurs naturally or spontaneously). I see that it's often used in the context of singing.