I think Jack's post is the most insightful in this thread so far.

'Humble, lowly, inexpensive' are not necessarily derogatory terms, and 'portable' is totally irrelevant. Can you prove the use of 'harp' here is mockery?

I don't think it's the "terms" but the implication. The JH is cheap. To those who imagine themselves better than the poor, that is often intended as a putdown. In fact, how often in this day and age haven't you heard someone exclaim "inexpensive, not cheap".

Also, the word harp is a put down. Like calling your old bicycle a limousine. That sort of thing is perhaps funny when the guy who can't afford anything else says it, but when a rich person says if with reference to the poor person, it can have some special tone.

Speaking of tone, has anybody here ever been able to discern any recognizable pitch in a J-Harp? I think perhaps it requires a trained ear to do so.