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Good day all. Some months back I finished my first cutaway dread with EAB back and Sides. It has a couple of the tonal behaviors I expected to be different from the EIR I normally use. I say this as compared to the 6 previous EIR guitars that were geometrically identical and all using the same top species, and for the most part, have been quite consistent in their sound. The Blackwood guitar projects quite a bit more, is noticeably brighter, and has a little less low end. Not surprising attributes, given my understanding of the species.

What I didn't expect was, what to my ear sounds like, fewer and more pronounced harmonics that make it much more sensitive to tuning. This isn't to say it doesn't play in tune, or can't be tuned satisfactorily, but it really needs to be dead on for my ear to enjoy.

Has anyone found this typical of the more dense tone woods? I don't have the need to do another in this species any time soon, but I'm wondering if this is something I can expect in the future, or if this was an atypical experience.

*insert every possible disclaimer about no two guitars are the same, every tree is different, you can't judge a guitar by it's species, etc, etc, etc.*

Not that it matters, but this is what it looks like:

I've only played 2 blackwood guitars, and they were both Taylors. I thought they sounded great, and I am not a Taylor fan at all. In fact, one of them sounded terrific and I recommended that a client of mine purchase it. He played it, but waited a couple days to make a decision - which he regretted. Someone else came in, and was told that I liked it, so they popped for it first.

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"Act your age, not your shoe size" - Prince

That's a beauty Terry.

Nothing not to like there at all. Like the headstock, bridge, armrest, woods, finish - well the hole shebang!

Nice work.

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Brian R, Wood Mechanic
N8ZED

Love the top of the headstock! All else is cool, too, but I especially like the leaf inlay.

Regarding the harmonics you don't like, the Gore/Gilet book talks about how the different resonances of the guitar can conflict and cause what is heard as a tuning problem. Maybe take some modal tuning diagnostic steps, like attaching some putty to the top or the sides, and see how it sounds with that additional weight in those locations?

Yea Don, that's probably worth trying. I usually do a spectrum analysis of the top's tap tones once the guitar is strung up for documentation purposes, but I built this one for myself and got a little lazy.

Thanks for the rundown Terrence, sounds like an interesting tonel profile. What does the E stand for in EAB?

Hard to believe Taylor is using African Blackwood, maybe Australian? Chris, you must have quite a reputation!

Pat

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Pat

Sorry about that. When I bought it from LMI (almost a year back now) I believe they were calling it East African Blackwood... though my memory isn't as good as it used to be. They no longer offer it, but have another term for the Blackwood they are selling. Haven't researched it to see what might be the difference.

African Blackwood is the stuff they make clarinets from, and is a Dalbergia species. And therefore a true Rosewood.

I wonder if what you're hearing is apparent for clarinets too?

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I like to use African blackwood (Dalbergia melanoxylon) for guitar bridges. Although it makes a heavy bridge I like the way it works with the soundboard. The blank has a lively musical sound when dropped on a hard surface.
It is a preferred wood for woodwinds, as Paul mentioned, which might be a better use than guitar back and sides for such a scarce wood.

Many years ago I had a wooden clarinet (I started in music as a clarinet player) and there's no denying the quality of sound, and the price, of a wooden clarinet. The resonance was strong, but very consistent... a critical factor due to the relatively large range of tones required with very little variation deemed acceptable. Comparing it to a saxophone (theoretically more consistent material) the clarinet (wood or plastic) is much more consistent of a sound across the range than a saxophone, which varies greatly in tone and intonation across its natural 2 1/2 octaves. Of course, the altissimo register gets you another octave above that, but it's a whole different game at that point... But, regardless of the range, intonation across the full range of a sax is a puzzle the player has to figure out for their specific instrument. (I've played sax for over 30 years).

Interestingly, the Saxophone's inherent problems with intonation haven't been worked out quite yet, where as the clarinet with its 200 year longer heritage has been more refined in terms of the sound hole design, imho. All that aside, clarinets can make pretty efficient use of a given tree, but have more strict grain, density and color standards than what we can effectively use for a guitar. They also need about 10 years to process, if done "correctly". But, I would have to agree that any given tree that meets both sets of requirements can probably provide more clarinets than guitars per raw board foot.

What's probably more interesting is that Clarinets are still being widely manufactured with the centuries-proven "perfect wood" of African Blackwood out of sustainable Forrests. Where as guitars can no longer be widely made out of what is arguably the "perfect wood" of Brazilian Rosewood. I don't want to get into a cites debate, or argue deforestation villains... it's just too bad that we are stuck in a world where the best wood for our craft is practically out of reach. In the mean time, It seems like African Blackwood is the closest alternative, short of planting new Forrests and waiting until we are all dead to get the wood

Wow, I really turned this into a non-guitar train... back to the instrument at hand!

The blackwood moniker can be confusing. As mentioned African blackwood is a rosewood with black color, Malaysian blackwood is an ebony with a greenish rust-ish color and Australian blackwood is similar to Koa in appearance.

Pat

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Pat

The African blackwood that I've tested has been dense and stiff, but has much higher damping than BRW. Normally one expects a high damping wood to 'eat' high frequency sound, but it may only do that if it's moving and bending. A dense and stiff back that's not moving much at high frequencies may not add much damping there. I've seen this with several different woods, in particular persimmon (North American ebony) and Morado/Pau Ferro, a Central American substitute for rosewoods. I have yet to make a Blackwood guitar, though.

Just to clarify; Australian Blackwood is not a Dalbergia. It's an Acacia (Acacia melanoxylon) as is Koa (Acacia koa).

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