Okay, maybe something of a CIDU-LOL. Google Translate is not as helpful as one would like — I don’t trust “cable castanets” . I do rather trust “box castanets” but why “light box castanets”? That’s not a “light box” as used in graphics arts, anyway. And I think the primary joke is our stand-in character enjoying “vulgar castanets” instead of “common-or-garden castanets”.
Is her expression already reacting to this irritating oversight?
But maybe this one was meant to make up for that?
Comics I Don't Understand 
Per Wikipedia, castanets can be handheld (3), mounted on a stick (1), or “machine castanets” (2) mounted to a base of some sort (in the illustration’s case, the rim of a drum).
But I don’t see any inherent humor here. “Vulgar” (the literal translation of “Vulgares”) simply means “common” (as opposed to “cultured”). I don’t know if it carries the modern English connotation of something uncouth or obscene.
Sorry for not closing my tag.
The illustration of castanets vulgares look like a nutsack, being vulgar in both meanings.
Castanets de cabo is more likely to be “Cape castanets” than “cable”. As in that style is originally from Cape Somewhereorother.
DMX, bear in mind that we’re working from Portuguese to English. The “cable” was just reporting (and yes, criticizing) what Google Translate came up with on its own. Your “Cape” suggestion does sound like a good idea.
@dvandom – LP (Latin Percussion) has a model, “LP® SMALL CAJON CASTANET” :~)
(Everyone, check out the history of Latin Percussion, the American Company which was created when the U.S. wasn’t allowing imports from Cuba. Actually, Martin Cohen tinkered for his own use, got private attention, and eventually created the company.
I just discovered that the Vivbraslap, a percussion instrument I have never understood when playing in music circles, was Martin Cohen’s invention replacement for a skull that would be hit to cause teeth to rattle in their sockets. )
Oops, clarification: you don’t hit the Vibraslap (I see I mis-spelled it above), you slap your hand with it.
oops again, the QUIJADA is a “dried-out donkey jawbone”, not a skull.
A video of how to play the Vibraslap has comments that include the many pop songs that have included a Vibraslap, including “Sweet Emotion” where the one Steven Tyler was playing broke, and they left it in the recording (on the 4th slap, the comments say).
Well, now I know of TWO musical instruments that are also weapons of war.
I already knew about bagpipes, used in battle to intimidate the opposing army.
The jawbone of a donkey was used as a weapon by Samson in the Bible. Judges 15:15.
There’s also the artillery used in a proper performance of the 1812.
Drums and fifes commonly used by British of course in the 18th century (and others) and I would presume by other countries’ armies as a means of communication to the men, same as drums were used in later armies and I am pretty sure the bagpipes were to the Scots.
Or am I misunderstanding what was meant?
A friend of mine (no longer with us) had been a piper in the Argyll and Sutherland Highlanders of Canada (Princess Louise’s). He could have told you all about the bagpipe as a weapon of war. A little research turns up the story of the trial of James Reid in 1746. Charged with treason, his defense was that he was a noncombatant and carried only a bagpipe on the field. However, the commission reasoned that Highland regiments never marched without a piper, and therefore in the eyes of the law the bagpipe was an instrument of war. Reid was found guilty of treason and hanged.
When bagpipes were captured in combat, they were not inventoried as musical instruments like drums or bugles; they were listed as weapons along with sabers and rifles.
The bagpipe was used by the Scottish as the equivalent of the fife and drum in the British (and other) armies. Depending on what was played the soldiers knew what to do in terms of fighting. So if the bagpiper was rendered unable to play there would be a lack of information to the soldiers as to what they should do in the battle.
Yesterday’s “Rubes” has an alternate take on the “Yo-Ho-Ho!” gag: