The idea of combining two 10-hole harps behind a single mouthpiece is not new - but it's not easy to get good reed response, and has never been done convincingly before. That's all changed! After intensive R&D over the past couple of years, I've come up with a quick-change assembly that really works. I'm now releasing my ground-breaking Twin-Diatonic harps in a range of exciting options - check out the two videos to see and hear them all in action.
An obvious choice is to make 8 of the bends the same as on stock harps (which only has 8 bendable notes), and the rest to go down a semitone. This gives a fully chromatic harp with bends alone, plus lots of cool 'bend enharmonics': notes you can get two ways, bending or non-bending. Another way is to tune the x-reed so the bends go down to the next note of the home scale, whatever that is. It's very expressive - I demonstrate a Solo tuned version in the video.
While you can just buy the front unit to assemble your own OctaHarp using stock combs, trying to fit single valves to combs not designed for them can be tricky and frustrating. Adding my specially-designed PowerCombs and Stealth-Valves to your order will simplify and speed up the process of making an OctaHarp that sounds great straight away. They are available at half-price when ordered for the TwinDiatonic harps.
The one essential part you require is the Front Unit. However, where appropriate, we recommend you also purchase PowerCombs and Stealth-Valves. They are specially designed to suit the TwinDiatonic harps; we can't guarantee all other combs will fit perfectly, and combs without valve pockets will definitely cause more hassle to install valves. (Lipped-comb versions will use the stock comb). You need to supply the harmonicas, or order them from your customiser. Please watch all the relevant videos above to help you make an informed choice of ordering option.
Joel is our recommended customiser to make your complete OctaHarp . If you would like to commission Joel then please place your order with him on his website below. Email: info@jaharmonicas.com Website: jaharmonicas.com
Tech 0: Making an Octa-Harp from the PowerParts kit
Tech 1: Assembly
The OctaHarp Selectable differs from my other small 10-hole octave harmonica (the OctaHarp) in two significant ways: the twin harmonicas are inline front-to-back, and you can choose to play them separately or together! The front harp is in the standard range, and the rear harp in the low range.
Only certain brands and models are available in both standard and low ranges. At present the OctaHarp Selectable is designed for Hohner (Thunderbird/Marine Band 1896/Crossover/Marine Band Deluxe) , Suzuki (Manji/Low Manji) and Seydel (Classic, 1847, Noble, Lightning - plus Low Versions) harmonicas.
The front harp has holes all the way through the back of its comb, which are blocked in the default position, so just the front harp sounds. The front comb slides along the face of the rear one, and is held in place by a small spring. With a quick press of your thumb or finger the two combs come into line, the through-holes open, and all the reeds on both harmonicas vibrate to give you that fat, rich octave sound. In single-harp mode the front harp plays exactly like a normal blues harp, with all the bending and expression you're used to. But you can instantly switch to playing it as an octave harmonica - it's truly two great harps in one! Check out the video to hear it in action.
I've shot a detailed instructional video on how to finish and assemble your PowerParts Kit for it - please watch before you buy. If you're the hands-on type and comfortable working with basic tools, you'll have no trouble following along with the simple steps involved.
If you don’t have the necessary making skills, or simply prefer to get a fantastic OctaHarp Selectable ready to play awesomely out of the box, we will send your PowerParts Kit to a harmonica tech/customiser of your choice to do the job for you. In that case the arrangement for the overall price and features you want is entirely between you and them. Here is a list of people you can contact to do the work:
Tech 2: Fine-tuning for Pure Octaves
Gasket Valves: Introduction and Fitting Demos
With my 2026 Universal Switch-Harp, I’ve addressed both of those issues. First, I designed it to be fully configurable – meaning the same assembly unit will fit virtually every harmonica brand and model on the market! Second, I swapped the moving mouth-slider for a new self-sealing mouthpiece/slider assembly. This has a comfortable fixed mouthpiece above a slippery Teflon slider, which seals against the main unit with the player’s mouth pressure.
No matter what harmonica model you prefer, you can now explore the huge potential of fitting two harps of your own choice into one unit, switching between them instantly. There are so many cool possibilities! One obvious choice for the Universal Switch-Harp would be for the slider to select between two harmonicas a semitone apart, to make a 10 hole mini-chromatic. This could be in standard Richter tuning, or in any one of many alternate tunings (eg. PowerBender, PowerDraw, Paddy Richter, Solo Tuning, Circular Tuning, Wilde Tuning… whatever you like!). And you can swap in different keys quickly and easily.
Watch the video showing how to fit the two harps into the Universal Switch-Harp unit.
The best range of keys to fit is from C down. Higher keys suffer from detuning of the high reeds due to the Helmholtz Resonance Coupling phenomenon. Even on lower keys you may notice some slight flattening on holes 9 & 10. If it bothers you, it can easily be fixed with fine tuning on the high notes. (I show how on in this video)
Although the Universal Switch-Harp will work OK using two stock harps, to get the best out of it I recommend slot embossing. Embossing will brighten up the sound and improve response – just as it does on stock harps. If you don’t emboss your own harps, you can give the job to a customiser of your choice. (As the Switch-Harp is an X-Reed product, I recommend my X-Reed partner Andre Coelho for the embossing job, as well as fine tuning – see Ordering Options below).
Another quick way to get better response on the blow reeds is to install my EasyFit PowerValves. These will go on any harp and are super quick and simple to fit – anyone can do it. If you want to try them, simply click on the ‘Add PowerValves’ option when ordering, and we include them for very low cost. (See how to fit the PowerValves here.)
Check out Kevin McCarthy playing his OctaHarp in a session. Your browser does not support the video tag.
" Excited to have my Melody Maker Switch Harp in hand for the first time! The sound is excellent. The mechanism will take some getting used to. Specifically, the slider movement is not like a chromatic because instead of having the slider move while everything else stays static, on the Switch Harp the entire mouthpiece moves within your mouth. Or alternatively, the slider stays fixed on your lips and the mass of the two harmonicas behind moves. After a few more minutes of play - a few more impressions. I'm comparing my Melody Maker Switch Harp to a Melody Maker X-Reed Sub-30, another fine harp! And now I'm realizing that if I push the harp further into my mouth and rest my lips on the covers, the slide moves more freely. Tongue blockers might like that embouchure more than pucker players like me! And the more I play the more I like it! Truly a novel and unique harmonica with an excellent tone. Jazmaan, From Brendan's Forum
After a few more minutes of play - a few more impressions. I'm comparing my Melody Maker Switch Harp to a Melody Maker X-Reed Sub-30, another fine harp!
And now I'm realizing that if I push the harp further into my mouth and rest my lips on the covers, the slide moves more freely. Tongue blockers might like that embouchure more than pucker players like me!
And the more I play the more I like it! Truly a novel and unique harmonica with an excellent tone. Jazmaan, From Brendan's Forum
" I really like my switch harp. Mine is a basically a pair of half- Valved Paddy Richter's. I haven't had as much time to play or experiment with it as I would have liked but it is a blast so far. The moving mouthpiece feels odd and unwieldy for about 20 minutes, and then it is no problem at all and feels natural. I can play fully chromatically with the button and bends, and can color every note with blow or draw bends or the slide. It's a blast. I will probably be retuning some more reedplates so I can make other combinations. It's awesome. You could build a case to hold a set of comb/ cover combinations and be ready to switch out in moments. " CrawfordES, From Brendan's Forum
Mine is a basically a pair of half- Valved Paddy Richter's. I haven't had as much time to play or experiment with it as I would have liked but it is a blast so far. The moving mouthpiece feels odd and unwieldy for about 20 minutes, and then it is no problem at all and feels natural. I can play fully chromatically with the button and bends, and can color every note with blow or draw bends or the slide. It's a blast. I will probably be retuning some more reedplates so I can make other combinations.
It's awesome. You could build a case to hold a set of comb/ cover combinations and be ready to switch out in moments. " CrawfordES, From Brendan's Forum