The Suzuki SSCH-56 chord harmonica was introduced at SPAH St. Louis, Missouri in 2013.
The unique feature of the harmonica is that it can play all 12 major and minor chords, as well as augmented and diminished chords. It’s 56-reed, 14-hole harmonica with just one slide.

Seydel’s Saxony harmonica was the first commercial non-customized chromatic harmonica with stainless steel reeds. It was introduced at the beginning of 2009 at the music fair in Frankfurt.  It was also the first 3 octave chromatic with an aluminum comb.

In 2017, 9 years after the Saxony, Seydel introduced a 4 octave instrument with stainless steel reeds and aluminum comb called Symphony Grand chromatic.

Around 2004, Suzuki came out with its unique SCT-128, 16 channels, 128 reeds tremolo chromatic. The patent #DE 20 2004 004 616 U1 was granted the same year
It is the only double-reed chromatic harmonica commercially available.
The main reeds are tuned to around A=444/445, with the secondary reeds tuned a fraction lower, giving it the characteristic tremolo effect.

The Renaissance chromatic was invented by Douglas Tate and Bobbie Giordano. It was first introduced at the 1997 Buckeye Harmonica Festival and shortly after that at SPAH convention in Michigan. After Tate passed away in 2005, Seydel continued producing the Renaissance.

The unique and revolutionary feature of the Renaissance is the fact that it does not show any screws or screw holes on the exterior. The mouth piece is attached to the comb by long hidden screws situated at the backside of the harmonica. The covers are attached without any screws at all.

The main materials used were stainless steel for the comb and silver plated brass for cover plates and mouth piece.

In 2015 Seydel stopped producing and selling the Renaissance.

From the Hohner website:
With its sleek good looks and the elegant simplicity of its construction, the CX 12 Black turned a lot of heads when it was introduced in 1992. It won the German Industry Design Award shortly afterwards.
The patent# DE 41 29 817 C1 was granted in 1992 to Horst Jakubaschk, Wolf Linde and Gunter Weber. Besides the unique design, the cover consisting only of one piece, it was also the first time Hohner used an internal compression spring similar to the Koch chromatic from 1927.

The CX 12 came initially in 5 different colors: black, gold, silver, ivory and maroon. Since 1998, only the black and gold colored ones were still sold by Hohner.
In 2008 Hohner introduced the CX 12 Jazz with a new mouth piece design.

In 1996, Siegfried Naruhn, Germany, made what he called the CB-16.
It’s a 16-hole version of the CX 12, with a brass cover.
In 1999, he also designed and built a special CB10 Wholetone chromatic harmonica for the Dutch Jazz harmonica player Wim Dijkgraaf. It was called Toni II.
Even though the instrument had only ten channels it had actually a range of more than 3 octaves.

Also on his website, Brendan Power has some photos of his custom CX harmonicas.

A Chinese website now offers copies of the CX 12 shell in new colors.
Since about 2002 there is also a Chinese manufacturer (Wuxi-Suzuki) selling clones of the CX 12 as well as a 10 hole version (Golden Butterfly WH-12 and WH-10).

From left, Golden Butterfly WH-12 and WH-10 (black) are from my collection.
The gray WH-10 seems to be a prototype

The first high-end chromatic harmonica I know of was the Silver Concerto, commissioned by the famous harmonica virtuoso Tommy Reilly in 1967. After that, Chamber Huang designed his own silver instrument, CBH 2012 in 1973 -> more info here.
Another high-end instrument to follow was the Renaissance chromatic by Douglas Tate and Bobbie Giordano in 1997.

Virtuoso
The “Virtuoso” was one of  Bill Romel’s high end custom chromatic harmonicas. I was not able to trace back the earliest release date but it must have been in the mid 90s.
The “Virtuoso” is a custom chromatic with a polished acrylic comb, custom cover plates, mouthpiece and slide designed to accommodate whatever reeds you prefer recessed into the comb itself. Bill Romel’s Harmonica Workshop produced also other custom instruments, such as the “Romello”. These other instruments were not quite as high-end. After Romel passed away in 2009 the production stopped.

Bill Romel’s flagship instrument “Virtuoso” (12 and 14 hole).

Genevieve
In 2001 Antony Dannecker introduced the “Genevieve”. He manufactured only 100 of these instruments. The Genevieve harmonica was first made for the harmonica virtuoso Larry Adler. Antony Dannecker (and before his father, Willi Dannecker) was actually Larry’s harmonica repair man.
The “Genevieve” (the name is based on the Oscar-winning composition by Adler) consists of a custom-made stainless steel body and cover plates.

Harmonica Art
The Harmonica Art company was founded in 2002 by Hong Kong’s veteran harmonica players, Johnny Chan and Tommy Leung. In their research developing high-end chromatic harmonicas materials like silver, brass and ebony wood were used.

The company was also experimenting with combining different materials. The slider button had a unique shape. Carved out lines in the mouth piece reduce friction and stickiness of the slider (similar to the concept developed by Georg Pollestad)

NC 64
In 2008 the Austrian harmonica player Franz Chmel introduced after five years of development and testing the NC 64. The full specification of the instrument can be found on his website. The NC 64 was equipped with specially manufactured stainless steel reeds. Two models with either gold or silver plated covers were produced. It was one of the first high-end 4 octave chromatic harmonicas.

Suzuki Fabulous
At around the same time Suzuki came out with two high end chromatic harmonica models: a 12 and 16 hole silver coated brass comb instrument called “Fabulous“

Cremona
The next company to produce and sell high-end custom chromatic harmonicas comes from Japan. The company called Harmonica Workshop Cremona opened at the end of 2011. The owner, Naotaka Kishi produces not only 12 and 16 hole but also 14 hole custom instruments. Every instrument is either made out of ebony, silver or a combination of both.

Psardo
Another more recent company to produce high-end chromatic harmonicas is Philharmonicas. The company was founded by Phil Sardo in 2016.
He produces a range of high- and medium-end 12 and 16 hole instruments. All come either with brass or aluminum combs. The special and unique feature of the “Psardo” harmonicas are the individual two-note reed plates set into precision pockets in the body of the comb and the tubular channel covers (similar to the molded in channels of the CBH 2012/2016 covers).

The Hohner’s “Meisterklasse” chromatic was introduced around 1982. It was the first high-end harmonica with 14 holes and  an anodized aluminum comb. An additional feature were its full-length cover plates, which extend all the way to the ends of the harmonica’s comb rather than sharply angling down before the ends to form an adjoining surface parallel to the reed-plates and comb.
From it’s introduction to circa 1990, Hohner received customer complaints about powdery residue originating from unplated brass reed plates contacting the aluminum comb. The production was stopped. A re-issued version came out about 3 year later (date not confirmed). Additional versions with slight improvements were released thereafter.

I found this interesting website showing a custom Titanium comb for the Hohner Meisterklasse:

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An interesting feature is the additional slide button at the lower part, similar to the CBH 2012/2016.

 

In 1973, while still working for Hohner, Cham Ber Huang was granted patent #2260752. The patent described a revolutionary new harmonica concept. The complete history can be read on Cham Ber’s website. The CBH 2012 and 2016 (12 and 16 channel models) came with the slide button positioned at the lower part of the harmonica, contrary to all Hohner standard chromatics at that time. The CBH was mostly made out of a specific kind of resin even mixing in Teflon to improve resistance to abrasion and wear.

 

There is a video of Cham Ber talking about his manually build CBH 2012 made out of solid silver.

Another interesting video was made available by Roger Trobridge about Cham Ber Huang CBH Workshop (from 1972).

CBH harmonicas were discontinued after a patent court trial between Hohner
and Mr. Huang. The patent went to Mr. Huang, and the CBH models were not made after 1983.

 

Hohner electric harmonica prototype, courtesy harmonica museum

The idea of an electric harmonica goes back to the 1920s. Pat Missin created  a very informative page about this topic. He also shows a picture of the Hohner  electronic harmonica prototype from the late 1970s. The prototype still exists. I had the fortune to take a picture of it at the harmonica museum in Trossingen, Germany. Unfortunately, nobody at Hohner can provide any information about its history. On top of that, the connector cable is nowhere to be found. Without that cable it is not possibility to get it to work. I would have loved to hear how it sounds.
The first really useful electric/midi harmonica was the Millioniser 2000, invented by Walt Miller. You can find the full story story about it online. It was quite an advanced technology for its time.

The DM48, developed by Erik Lekholm is the most recent addition to the world of electric harmonicas. The DM48 is a MIDI controller and needs to be connected to an external MIDI device.

Cham-Ber Huang was the inventor of the Chordomonica I & II . His patent request for the Chordomonica II was granted in 1968 with patent# 1255465. Some brief info of the patent can be found on Pat Missin’s side as well as an extensive explanation of the tuning for both models.

Since 1981 Hohner discontinued the production of both models.
The patent ran out in 1983. There are now some different custom version of the Chordomonica available.

4 and 3 Octave version using the standard Chromonica cover plates

There is also a Chordomonica project website with another custom version using a customized Hohner Discovery 48.