@randy-adams, I'm in the @Nate fan club myself, but neither you nor I are as cute as those Swifties who will be joining us once Taylor plays a jell-o mold dulcimer in a Super Bowl ad.

Your comment about the number of professional dulcimer players in interesting.  How many professionals were there in the mid-1960s?  I have no idea.  But I bet there are more now. The internet has allowed folk musicians to reach a much larger market than would have been possible before.

Since I learned from Jean's column and before the 6+ fret became standard, I use DAA tuning most of the time.  I find chording easier (probably because I'm more familiar with this tuning.)

I first became interested in the mountain dulcimer after reading a Teach-In by Jean Ritchie in Sing Out! magazine in the early sixties.  Soon after that I bought Jean Ritchie, New Lost City Ramblers and Richard & Mimi Farina LPs with dulcimer playing on them.  I built my first crude dulcimer from hollow door mahogany and model RR plywood for the top, circa 1970. 
In the last decade I have had three musician friends buy dulcimers and have had two people request lessons.  There seemed to be a dip in the visibility of dulcimers after the great Folk Scare of the sixties, but in the last decade or so, they seem to be making a come-back.

My home made dulcimer

homemadedulcimer.jpg  •  32KB

This is an interesting conversation. I don't think there is a good method for measuring a decline or increase in popularity. Is it possible to compile a list of everyone building mountain dulcimers 15 years ago and today? Or a list of dulcimer clubs? Or the number of subscribers to Dulcimer Players News? Since the pandemic there seem to be less festivals and in person festivals seem to be declining in attendance. I have no concrete data to support this. Meanwhile, online mountain dulcimer groups and festivals seem to be increasing. Again, no concrete data. Two new museums of the Appalachian dulcimer have opened in the last year. I've been part of the mountain dulcimer community for over 50 years. I know many more dulcimer folk today than I did back then. Personally, I've never met anyone who told me that their interest in the mountain dulcimer began because it was included in a Rolling Stones, Aerosmith, or other concert by a popular musician or band.

Ken

"The dulcimer sings a sweet song."

Come to think about it, I guess it never really was what you'd call a popular instrument.  And one of my favorite quotes about the dulcimer went something like this:

"The mountain dulcimer.....that quiet, peaceful, personal instrument; meant to be played in some lonely log cabin, down some dark holler."

I believe I read that in "Four and Twenty" , a songbook which used to be included with McSpadden dulcimers.  I think Lynn McSpadden probably wrote it.  Of course, that was before the internet.

Hey now Dusty, the Nate fanclub may be small, but it has a quality few members. xD

I'm  a member! Quality debatable. : )

FB has numerous dulcimer groups w/multiple posts per day.

The online dulcimer get togethers have provided an opportunity for pro dulcimer players to pocket some jingle.

Biz is booming!

Though I can't recall where I saw it, Harry Styles got a dulcimer from Joellen Lapidus.  

Taylor Swift and Tracy Chapman, as I read in one of the more recent issues of DPN, purchased Blue Lion mountain dulcimers some years ago.  

One of the lovely things about the mountain dulcimer is they feel like such personal instruments-- meditative, even.  Though famous singers may own the instruments, they may not be part of public performance for them.  And that's cool, too.   

At least here in California, John, the majority of people who picked up the dulcimer in the early 70s did so because of Joni Mitchell and Richard Fariña.  There was no pre-existing dulcimer tradition out here until people heard those two pop stars.  And many of those people are still around, playing and teaching others.

When I got my first dulcimer I was employed teaching beginning guitar to some middle- and high-school students.  I brought my dulcimer in to show them my new toy, and they all got excited because they had just seen Cyndi Lauper play one on TV the night before. But by then, Lauper was old news.  When she had her hits back in the 1980s, she never appeared with a dulcimer (nor any instrument, for that matter).  Had she done so, perhaps I would have discovered the dulcimer decades earlier than I did.

Hey now Dusty, the Nate fanclub may be small, but it has a quality few members. xD

It's a very true point though. Popular artists of the 70s played a huge role in the re-emergence of the instrument. Joni Mitchell, Emmylou Harris, Led Zeppelin, Rolling Stones, etc. Often when you look at the comment section of tracks from that era that included dulcimer you will see people talking about how the sound stood out to them.

In modern times, Harry Styles, who was a member of the popular boy band One Direction, had a song that heavily featured the dulcimer and while his audience probably didnt notice, as a dulcimer player I definitely did.

Has the dulcimer playing of artists such as Brian Jones or Joni Mitchell or Cyndi Lauper or Dolly Parton made a measurable difference?  I don't know.

Maybe Ms. Swift should consider playing a dulcimer, if she could only sit down for two minutes in her concerts.  Attention would certainly be drawn to the dulcimer in such a situation.

Interesting question.  I'm not sure how to measure it, either.  The dulcimer was never a popular instrument. Even in Appalachia in the 19th century, it was less common, surely, than fiddles, banjos, and guitars.  The folk revival did indeed represent an apotheosis of sorts, but importantly, a lot of the people who took up the dulcimer then are still involved in the instrument. I've learned from many of them (Neal Hellman, Joellen Lapidus, Holly Tannen, etc.)

The original question references only the last 10-15 years.  Since I first discovered the dulcimer 13-14 years ago, I think my own perspective is useful here.

Until the pandemic, the number of dulcimer festivals was increasing.  And throughout that period, the number of people engaging about dulcimers online (FOTDM, ED, Facebook, etc.) has also been increasing.  In terms of the sheer number of people who own or play the instrument, I think there are more people involved now than there ever were.

And I'm not sure that the number of "commercial" builders is a measure of an instrument's popularity. First, as @Nate says, the dulcimer is relatively easy to build, and a lot of people build dulcimers for themselves or close friends. Second, and I will argue this until the cows come home and crush our tuners, we now have a small number of phenomenal luthiers making instruments that far surpass in quality of tone and playability the vast majority of instruments made in the past.  Even long-standing "commercial" luthiers such as Folkcraft and McSpadden are making much better instruments than they did decades ago, and if you add New Harmony and David Beede and Ron Ewing and Jerry Rockwell and Terry McCafferty and so many more, I think the number of outstanding dulcimers being produced is greater than ever.  Makers of some less impressive instruments have ceased, but I think that's not a bad thing.  Additionally, the market has been sufficient for low-end commercial builders like Roosbeck to enter the fray.

Having said all this, imagine if Taylor Swift would just play one song on the dulcimer in one of her concerts, I bet a whole bunch of teenage girls would get turned onto the instrument and before you can pick up your noter, there would be a NateBuildsToys Fan Club formed, their insignia a jello mold in the shape of a treble clef.

While I totally agree with you Wally, I think that dulcimer has recently rediscovered it's place as an instrument that is great for amateur builders to make for themselves. I have personally taught a bunch of people to build dulcimers. With modern tools and hardware, it's easier than ever for people to make their own dulcimers, and for people who like to build instruments, dulcimers and strumsticks are a common project.
Personally, I mainly built cigar box guitars before learning about dulcimers, and I have preferred making dulcimers since.
I think that the lack of commercial viability is also an indication of the durability or dulcimers, and the care given to them. There are probably more dulcimers out there than dulcimer players, so making new ones is best left to folks who make exceptional instruments, like many of the fine luthiers on this site.

One measure might be the number of commercial producers of dulcimers. That has certainly declined.

Certainly not my interest! I really want to know what folks who have been playing for decades think about this.
I am a young person and have not played for very long so this observation is limited. From my conversations with others, it seems that the instrument has been on a slow and steady decline since the folk revival. I think the instrument has incredible potential for a come back, but at the moment I would say that the popularity sadly seems to be on decline.

Has the popularity of and interest in the mountain dulcimer declined in the last 10 or 15 years?