Tonewood Differences Measured: Interesting Study

[JohnnyPustular]

Interesting post. I thought the study was quite interesting and fundamentally sound. I just wanted to offer a few clarifications on the comments regarding the scientific value of the study. First, science does not prove anything, that is not what scientists do. We build explanations and then test those explanations where they are weakest so as to ascertain whether the explanation is incorrect. Then we modify and test further. It is by attacking the weakest parts that we avoid the "black swan fallacy". Therefore, it is unfair to hold this study to that standard. Further, it is a bit ridiculous to think that one study can test all possible facets of the question at hand. No single study can definitively answer all the questions raised in the comments. Instead, scientists isolate parts of a phenomenon; the collection of the results from isolated parts paints the bigger picture. Third, I don't know what a "control group" for this study would be? A control does not nave the construct being tested (e.g., a placebo in a drug study). What would constitute a control in this case? Air? Plaster? And what would that control have to say about differences among woods? Next, some posters are correct that the experiment should have had some number of boards of each variety. In that way, we could see variation within species and the degree to which we might be fooled by a particularly melodious piece of plywood verses a very dull piece of pine. It would also facilitate a test of significant difference as we would have a standard deviation from which confidence intervals could be calculated. There is no standard deviation in a single board.
It is generally a good idea to read the study before commenting on it so one can see that they controlled volume via the plucking mechanism and how the "guitars" were built. They were careful and their internal validity is good. Some commenters are correct that these are not real guitars played on a real stage by real musicians. that is an issue with external validity. The balance between internal validity and external validity is a bit of a zero sum game such that it is highly improbable that this question can be answered in a single study that has both high internal and high external validity. The researchers need to choose one and he critiqued on the extent to which they met that criteria.

 

[Doug4321]

I would reiterate that whether there's a systematic difference between one kind of wood and another, the results in the paper show an audible difference between those pieces of wood. The wood can make a difference in tone. We well know that wood is an organic material with significant variation among different pieces. I wouldn't expect a "tone wood" to universally exhibit particular characteristics. There may be ... tendencies ... in different species, would be my own take on it. Regardless of that, different individual pieces of wood may contribute some difference in amplified tone, as heard by participants.

Yes, that’s significant. Some people here have said that the wood can’t make a difference since the sound is only generated by metal strings swinging in a magnetic field. That is, the system is deaf to anything happening beyond the interaction of the string and the pickup.

I think this study is pretty good. A little bit of lost opportunity with the pickups vs the woods, maybe which made a bigger difference could have been shown. Also would be nice to have maybe three or four examples of each wood to maybe find a consistent property of the wood type.

 

[GodPlayedBass]

I posted about this 2 days ago and got so much hate. Now that a study has been done I'm laughing at those haters!

 

[rantbot]

Very interesting, in a tedious sort of way.

It's easy to criticize such a study for what it doesn't investigate. This is a limited study of one variable, and it doesn't pretend to be anything more. It demonstrates that some sonic responses of some materials are perceptibly distinguishable by human ears. This is a perfectly reasonable thing to demonstrate. If there are no distinguishable differences, further speculation is unwarranted, and investigation of the topic can be abandoned. But that's not what this study shows; it shows that there are detectable differences. It doesn't address whether these differences are always apparent, nor whether they're important. Nevertheless this is interesting, and perhaps even useful, information.

Dumping on the paper for failure to test all imaginable variables of materials and geometries would be like rubbishing a study of the electrical properties of the P-N junction because it didn't evaluate completed semiconductor components or circuits, or complaining that a comparison of different processes for vulcanizing rubber is flawed because it didn't evaluate stopping distances of truck tires.

The major problem I see is that materials are not well constrained. That is, what the hell are sapele, pine, rosewood, and plywood, really? There are more than 100 species of pine. Some of the woods called "pine" in commercial trade aren't even pines, but are actually firs or spruces or even (gasp!) cedars. Some two dozen species of rosewoods are considered "true" rosewoods (whatever that means--the name originates in the odor of freshly cut surfaces, and odor is hardly a mechanical or acoustic property), and far more are sold commercially as rosewoods, whether "true" or otherwise. Nearly all woods are harvested as logs containing both heartwood and sapwood. The appearance and physical properties of the two can be radically different. Sometimes it is precisely these differences, as in the various types of yew, which make the wood particularly useful. In other cases, such as the maples or ebonies, the differences are mainly visual, but buyers expect the wood to be a particular color. So the "wrong" colored wood is processed in ways specific to the wood, such as steaming or dyeing, and then both processed and unprocessed wood are mixed together and sold in bulk. In other cases, such as Brazilian rosewood, the heartwood is decayed and useless, but the sapwood is not only usable but very expensive. And to make it worse, even after species is specified, the mechanical properties of the wood are not (cf. "swamp ash").

The "plywood" thing particularly burns my biscuits. "Plywood" by itself is an utterly useless term. Any block made up of plies of glued-together wood is plywood. A plywood can be made of hornbeam and desert ironwood, say, or more likely an inexpensive assortment of pines, spruces, firs, etc. Properties might be anything - and that tailorability to intended use is one of the great virtues of plywood. So is the plywood tested here mere scrap junk made of wood too poor even to be used for shipping pallets, or is it the sort of plywood one might use to construct a high-performance aircraft?

Personally, I still don't think the wood in most instrument applications is of much interest or any importance as long as it's strong enough for the application (see: neck joints, Kay double bass). This doesn't mean that I insist that differences in wood are "undetectable"; it means I still think they're "unimportant". But then, I never claimed to know what I'm talking about.

I'm currently making a bass body of 1-piece "swamp ash" not because of its musical properties, but because when I went to sell it as a blank I found a couple of tiny holes doubtless from some sort of boring beetle, and I won't sell it like that, so I can either throw it out or make something of it.

 

[themickster]

I can't believe I am posting about this.

I can

 

[GMC]

I have read the pdf...I have watched the various youtube vids. I have also built 8 very different basses and these are my observations and opinions...your mileage may vary. Bass guitars deal with much thicker strings and guitar and hence (obviously) lower frequencies. Our scale length is mostly set to 32", 35" but most commonly 34". Pickups, electrics / electronics and strings make the biggest tonal difference. Aluminium bridges sound brighter and clearer than steel or brass. Fret material and dimensions also have a play. Bass construction has an influence too, I can hear and feel a difference in compression between a neck though (or Set neck), bolt-on builds. I also hear a difference between headless and regular headed design. Large hollow chambers in a body make a different sonic flavour than solid bodies. String choice and materials have a huge influence on the tone too. Flats sound different to rounds, stainless vs steel. Acoustic core strings and tapes wounds sound different again.
I personally believe (and this utterly unscientific, and very open to comment, critique and change) that in a solid body / neck construction that the "tone wood" has an influence but in a negative fashion. I think that the influence that tone wood has is from removing certain frequencies or sonic bias from the transmission of vibrations. IE an all maple build tends to thin down the bass, not add to the brightness. Let me explain, I believe in a perfect set up, the body and neck (ie free air) can ring and resonate without complication of body/neck/fretboard wood material's interference. When we have some specific wood we introduce complication, resistive resonance and this in turn creates a bit of character. But I think it's the removal of frequencies and the addition of ununiform masses and structures in the wood that causes this. I think that materials like Carbon Fibre are stiffer but uniform density through it's mass in any direction. So it performs more like free air than wood.
I believe that bolt on and headless construction has a different compression to through neck and set neck construction. String height changes the volume and frequency balance. Some of the above also affect how a bass feels to play and that in turn (psychologically) influences how we play it...and then how it sounds.

I like fancy looking tonewoods on some of my basses and I have recently built a pink paisley P bass. I built them for looks as well as tone. However...my P bass sounds and plays a lot like a 50's P bass and my Piezo loaded fretless semi -acoustic (Rick Turner & Rob Allen influenced bass) sounds a lot like an EUB, nothing like a P. I am about to start a build for my Son...we have selected a solid Padauk body because he likes the colour, not for it's tone. He chose his pickups and electrics for the basses intended role and voice "vintage" and bridge material for it's edge. Strings are his choice.

At the end of the day...bass goes Doouummmm and fretless goes Mmmhhhwaahhhh. In a congested mix, all bets are off. However, if you like multi laminate Alembic...enjoy....if you like a 1975 Jazz or a Rick Turner Renaissance bass...enjoy.

 

[mongo2]

Warmth put out a couple videos something along those lines, I could call the difference right each time without fail. That's just me, but it certainly reinforces my belief that there can be a noticeable difference with different woods. People who haven't experienced this will likely feel skepticism. So it goes.

You touch upon an interesting point, that being the ability of the listener to notice differeneces may be the deciding factor.

 

[lomo]

Third, I don't know what a "control group" for this study would be? .

Depending upon which part of the hypothesis is to be controlled (each piece of wood sounds different vs species of wood sound different), a control group would be the same piece of wood tested multiple times, and/ or multiple pieces of the same species tested.

 

[lomo]

You touch upon an interesting point, that being the ability of the listener to notice differeneces may be the deciding factor.

Exactly. Which is why a large number of listeners listening to multiple samples would make the test meaningful. Sample size matters....enormously, I terms of getting results that are meaningful.

 

[gumbynotpokey]

Well, I can say one thing about the article itself. The abstract uses the phrase "just noticeable difference". In case anyone didn't know, that is a term in the area of psychology called "sensation and perception", and it goes all the way back to the 1800's. German scientists, notably Weber and another with the last name Fechner, worked in that area of inquiry - called "psychophysics". For example, place someone across a lake on a moonless night and make sure your watches are in synch. At a set time, the person across the lake lights one candle per minute until the other person on the other side of the lake can detect a speck of light. The amount of light required to make a "just noticeable difference" is the LIMEN or "limit" for the JND. That word "limen" is where we get the word "subliminal" - meaning below the threshold of noticeability.

Ok, that's it for the paper.

And that leads me to this. I thought the tonewood topic was truly resolved long ago, in this way: "Is there a difference in a studio or your bedroom? Probably. Is there a difference in a band context playing out live at concert volume? Probably not."

And that goes back to Weber and Fechner....They determined that the size of the JND rose geometrically as the initial background stimulus intensity changed. In other words, against the black background of the moonless night the JND is tiny. But a band playing out live at concert volume renders the requirement for a tonewood difference to be so geometrically gigantic to be detectable, that the difference that IS there is not.

Have a nice day, TB.

YMMV. Carrots. Best bass for metal. Tort guard on P with flats, and all that stuff.

 

[-Asdfgh-]

OP, thank you for linking to the actual study and not just referencing from it. The authors concede that the effect of the wood is a smaller consideration on an electric guitar compared to an acoustic guitar and they limit their sample woods to sapele, rosewood, plywood, and pine, however do conclude that "[m]ost listeners, despite the lack of a professional listening environment, could distinguish between the recordings made with different woods regardless of the played pitch and the pickup used." My ear is not so attuned so I would bet that (to me) they would all pretty much sound the same, but it was interesting to read the results of an actual controlled study.

Sapele, plywood and pine - not generally reputed as tonewoods, and rosewood is rarely used to construct a body, unless you are George Harrison. So odd choices.

 

[-Asdfgh-]

And multiple wood samples from different sources.

As always, terribly flawed methodology throughout AND not at all reflective of real-world scenarios.

Even if for some reason someone were to accept it though, this part was most amusing: “The test also showed that certain wood combinations were much harder to distinguish.” It makes the “I selected these 9 different tiny strips of wood to impart these specific tonal characteristics…” statements even more funny.

Is that a win/win, or a lose/lose?

They might be better off creating one of those cardboard and resin bodies for a bolt-on neck, and then a concrete guitar, and seeing if people can distinguish those as those are probably the two extremes. And ensure that the recordings are normalised relative to each other. And also do things like not just do AB and ask the difference, but multiple combinations of A and B in random orders, different for every listener.

 

[mcnach]

I can't believe I am posting about this. As a long-time member of Talkbass, I know --Lord, I know-- that these threads never end well.

But this study is interesting and worth sharing. It was recently published in the Archives of Acoustics by several researchers in Department of Mechanics and Vibroacoustics at the AGH University of Science and Technology in Cracow, Poland. It concludes that that different tonewoods in an electric guitar produces a measurable and audible difference in sound:

Abstract (excerpt):
"The presented study examined how the sound of a simplified electric guitar changes with the use of various wood species. Multiple sounds were recorded using a specially designed test setup and their analysis showed differences in both spectral envelope and the generated signal level."

Conclusion (excerpt):
"The tonewood used in the construction of an electric guitar can have an impact on the sound produced by the instrument. Changes are observed in both spectral envelope and the produced signal levels, and their magnitude exceeds just noticeable differences found in the literature. Most listeners, despite the lack of a professional listening environment, could distinguish between the recordings made with different woods regardless of the played pitch and the pickup used. The conducted test does not allow any conclusions regarding a more holistic outlook on a guitar’s timbre, as the observed relations are complex beyond the scope of the obtained results. Further tests regarding the guitar’s entire frequency response are required. It should also be noted that these tests were conducted based on a simplified guitar model, which might have overemphasized the researched phenomenon.”

The whole article is here: Jasinski et al. Archives of Acoustics 2021, vol. 46 no. 4, pp. 571-578. https://journals.pan.pl/Content/121810/PDF/aoa.2021.138150.pdf?handler=pdf

Let's discuss the study. There's another thread going on here The Tonewood Debate - Finally Solved? that's a forum for subjective opinions about whether tonewood matters. I get it: some think it does, others think it doesn't. Let's not clutter this thread with that noise, and instead let's critique and discuss this interesting study.

That last paragraph reflects optimism that is almost surely misplaced.

Interesting but incomplete, as they're missing a crucial aspect in my opinion: they should have used multiple examples of each wood to get a sense for the variation among a single 'species'.

What they show for each wood is the variation between measurements, or the technical reproducibility. That's cool, but it doesn't say anything about the variation between different examples fo the 'same' wood. That metric would be far more informative.
I imagine some woods will exhibit far more variation than others, and for some the overlaps will be pretty big while for others the overlaps will be small, giving far more predictive power to their usage...

Otherwise, we're still talking anecdotal evidence. I'm pretty certain there are real differences (whether big enough to matter to individuals, that's another matter, it clearly matters to some and not so much to others) but when you get some ash that seems porous and light and other much tighter in grain and heavier, you can't just take one single sample and extrapolate to the whole species. I mean, you can but if I were a reviewer I'd ask for some further work or to qualify their conclusions accordingly.

 

[BassToGoGo]

Another tonewood debate?

I'm sure this one will also gone on for many pages but the bottom line is everyone hears differently...

When it comes to tone; wood, hardware, strings, finish and even how the instrument is played has an effect on how it sounds. What I hear may be completely different to what you hear.

YMMV.

 

[-Asdfgh-]

I have a Strat made out of basswood, although it's more like balsa... I also have a bag of cement in the garage. If I get sufficiently bored over the summer maybe I will use the existing one as a mould and make a cement Strat and compare the tone. Or maybe a Telecaster is easier to cast and drill out as the trem would be a pain to drill and set up on cement. Or maybe I will make a cement body for my Harley Benton knock-around fretless bass. It'd be lighter out of cement...

EDIT: I am not messing around with bags of cement on a cold and wet January afternoon. Also I realise I'd need a lot of silicone rubber to make a mould which sounds like it would cost £££. I could spend that on strings or set ups.

 

[LetItGrowTone]

I think we do have a loose consensus here among the reasonable posters, but it remains complicated enough to be expressible in different ways, and that's good enough for me. Congratulations TalkBass!

 

[mongo2]

Exactly. Which is why a large number of listeners listening to multiple samples would make the test meaningful. Sample size matters....enormously, I terms of getting results that are meaningful.

I agree that larger sample sizes are usually good, however it's still necessary to account for the hearing idiosyncracies that the listeners may have and with a large sample size that could be extremely difficult.

I think in a test like this human listeners might not the best selection due to those idiosyncracies in hearing and other perceptual/experiential differences. But I'm a retired electronics engineer with 25 years of experience with spectrum analyzers in testing so I tend to trust the machine more than people in this type of comparision.

I've learned to listen to gear as objectively and without prejudice as I can and it hasn't let me down yet. I still like what I like and that what it's really all about. Go with what you like.

 

[Rib 13]

The conclusion is a "No poopie, Sherlock" excercise...I dont think anyone denies there is an impact made by wood that can be heard....What isnt ascertained is (1) How much of a difference it makes to each listener and (more important 2) as every individual instrument is case sensitive in and of itself, can the qualities of other electronics/pickups/hardware make up for any of these deficits in a delicate balance to achieve a certain tone and/or quality (if the listener with the microscope really cares that much)....If a listeners answer to (1) is mostly negligible and (2) yes, then the wood preference importance to a person is muted or understated.............There is no experiment, study, or scientific formula that can be attached to someones opinion to invalidate it.....This is why I usually do this in threads about tonewood:

 

[TyBo]

The conclusion is a "No poopie, Sherlock" excercise...I dont think anyone denies there is an impact made by wood that can be heard....What isnt ascertained is (1) How much of a difference it makes to each listener and (more important 2) as every individual instrument is case sensitive in and of itself, can the qualities of other electronics/pickups/hardware make up for any of these deficits in a delicate balance to achieve a certain tone and/or quality....If a listeners answer to (1) is mostly negligible and (2) yes, then the wood preference importance to a person is muted or understated.............There is no experiment, study, or scientific formula that can be attached to someones opinion to invalidate it.....This is why I usually do this in threads about tonewood:

View attachment 4563589

I've seen people deny that there is an impact made by wood that can be heard. So a demonstration of people hearing such a difference strikes me as useful there. As for how MUCH difference it makes ... depends ... .

 

[Rib 13]

I've seen people deny that there is an impact made by wood that can be heard. So a demonstration of people hearing such a difference strikes me as useful there. As for how MUCH difference it makes ... depends ... .

For me: not all woods, but with many the difference is so slight and miniscule, I may be apt to say "No difference" myself -- if anything, just to save time and paragraphs about nuances that arent going to make the world spin any faster