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Post by Deleted on Feb 2, 2015 0:32:34 GMT -5
Thanx Cyn1, by smaller frets do you mean height and/or width? What is the theory behind it? After doing many experiments yesterday with string action height, pickups height, looking closely to the saddle and trying to find out where could be the loss of energy attributed to, I had a thought: This is the place underneath the neck where the hole sawdust wood glue fix wad done, and I tightened the screws really tight, in order to maximize stability. Well stability was achieved, but maybe, this compression of wood had a negative impact of tone over the last 3-4 frets? I put my ear on the upper body wing and pluck the guitar on 20th fret, it rings loud my ear can sense it very well. I pluck on the 24th fret and the sound is so weak. Maybe I overtightened this area of the neck? Thus having some strange effect with self-cancelling or otherwise dampening frequencies?
As far as the refret of 1 fret costs in my neck of mediteranean, i went yesterday with the Carvin, and they said some stupid things (e.g. the guitar just needs a setup, yeah like i didn't how to turn the truss rod), and also refused to change the frets. Ain't be visiting there any time soon.
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Post by cynical1 on Feb 2, 2015 1:31:07 GMT -5
The theory is that you can only "flatten" the relief on a neck so far, and since the last 3-6 frets are over the heel of the neck, where no relief exists, you can shave a few decimal points off of your action by putting a lower profile fretwire in place. I've done a few of these, and no one asked for their money back. I did a few where I started stepping them down at the octave, but that's a bit more work leveling and recrowning, but it allows you to get about the lowest action possible. Keep in mind, you get the action too low and you'll get a string buzz blowing too hard on a string... A super light touch is required for this type of setup. I assume, based on you mention of a "repair", we're talking about the 7 string Ibanez. I don't know off the top of my head what the exact fretwire size is on that model. All fretwire measures with the same 3 dimensions: You're not shaving that much off the height, but you will probably wind up a tad narrower with the shorter height. The tang dimension is normally only an issue going to a larger fretwire size, as you may need to deepen the slot on the beefier wire sizes. I'd guess an e-mail to Ibanez asking what the factory wire size will get you what you need to know. Make sense? HTC1
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Post by Deleted on Feb 2, 2015 2:50:10 GMT -5
Makes sense Cyn1, and this technique is used on strats a lot. People give this "fade away" shape to the last frets on order to solve the problem you mentioned. In my case the situation did not improve no matter how I experimented with string heights. The strings do not buzz. The problem with 22nd->24th frets is not buzzing. Otherwise the 24th would ring very well since there is no obstacle to it, right? Especially since I took the pups out of the equation by lowering them. I did found this : guitarless.com/2010/12/kill-that-dead-spot-2/If the theory of this guy is correct, then my problem might be that I compressed the wood on the neck around the trepezoid area where the screws go. I noticed the 24th fret which is the least sustaining, it sits right on the two right-side (bridge-side) screws.
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Post by cynical1 on Feb 2, 2015 12:21:46 GMT -5
I've seen the "Hunk-O-Brass" gizmo mentioned in the article on a few different instruments. There is logic to it, but as he says in the article, most of the difference is probably just a subjective perception after dumping $30.00 on a piece of yellow metal.
I have seen guitars and basses come through with real dead spot issues on the last 2-3 frets. Most times it's an issue with string gauge and the contact area of the actual fret. Other times it's the fret profile, still other times it's the pickup set too close to the strings...then there's the loose fret gumming up the works...
It's a real trial and error process. I could rattle off a half dozen things to look at, but I might just as easily be sending you off chasing your tail.
One question: Did you ever work out a shim for the neck pocket in all your trials and tribulations with this guitar?
Ain't this stuff fun?
HTC1
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Post by Deleted on Feb 2, 2015 12:47:42 GMT -5
I've seen the "Hunk-O-Brass" gizmo mentioned in the article on a few different instruments. There is logic to it, but as he says in the article, most of the difference is probably just a subjective perception after dumping $30.00 on a piece of yellow metal. I have seen guitars and basses come through with real dead spot issues on the last 2-3 frets. Most times it's an issue with string gauge and the contact area of the actual fret. Other times it's the fret profile, still other times it's the pickup set too close to the strings...then there's the loose fret gumming up the works... It's a real trial and error process. I could rattle off a half dozen things to look at, but I might just as easily be sending you off chasing your tail. One question: Did you ever work out a shim for the neck pocket in all your trials and tribulations with this guitar? Ain't this stuff fun? HTC1 I kept the factory shim, which was a tiny piece of thin paper. I read over jemsite that *all* Ibanez's have one, so I kept it, in order to feel "I kept this stock". So you rule out the compression thing, right? Now that I think about this, it might be this shim. Or the compression, or a combination. The "pattern" of the fade out of the sound, is that it starts bright and strong and then prematurely dies instantly. This doesn't sound like a fret issue right? The frets seem properly seated. I hit them lightly with a metal object and I dont hear anything for the last 4 frets than the others.
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Post by JohnH on Feb 2, 2015 14:29:17 GMT -5
I've got two thoughts, which are speculative:
I think physics will determine that the strings must sustain less on the high frets than on the low frets. If this is true, one reason is simply that the frequencies are higher.
I get involved in assessing building vibrations. These are two or three orders of magnitude slower than string vibrations, but much of the same science applies. The collection of effects that causes a vibration to decay is called the damping, which results in energy being lost from the system. In certain sorts of systems we refer to the % damping which is variable but somewhat consistent for similar types of structure. eg, for a bare steel structure, we expect around 1% (100% is 'critical damping', the system returns to steady state with no over shoot or vibration at all - like its moving within treacle).
Damping for a musical string is very low, and we want it lower. It comes from loss of energy to the air, to the guitar body etc. For a given damping %, every time the string goes through a cycle, it loses a certain small percentage of its energy. So, if high-fretted strings have the same % damping as low fretted ones, and if we pluck the strings with the same energy, the high fretted strings will go through more cycles quicker and hence decay quicker, all other things being equal.
My other thought is about the shape of frets to promote sustain. Fret profiles generally have rounded tops, as in cyn1's diagram above. When we press on the fret, we clamp the string down with enough pressure to stop it moving at the crown. No energy is lost there. Once it leaves the fret, again there is no interaction between fret and string. But Im thinking that the part of the fret where the crown is rolling away down to the fret board, will be a zone where pressure between string and fret is gradually reducing There will be a tiny zone, just before the string leaves the fret, where the pressure is low enough that there is not enough friction to lock the string to the fret. hence there will be some miniscule sliding of string against fret, resulting in friction, adding damping, reducing sustain. To address that, one would want the bridge side of each fret to be very steep, like a cliff rather than a hill so the string goes instantly from fully clamped down to completely free..
As I say, I'm just guessing here..
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Post by cynical1 on Feb 2, 2015 15:17:54 GMT -5
To take John's idea and extrapolate, what is more common than "shelving" a fret is to make a soft pointed crown versus the more common rounded profile. By minimizing the area of contact and applying a lighter pressure you can get your note with less effort. Granted, this profile does wear faster, but on the higher frets where you don't spend as much time, the "soft pointed" crown with a lower height crown has worked well for some players.
This is not a bad job on a half dozen frets and can be done in a few hours with some very simple tools.
John's point about the shorter string distance from fretted note to bridge is a very valid one. Normally this takes care of itself if the pickups are adjusted correctly, as the strings get closer to the pickups the higher you fret. Essentially what you lose in string vibration you make up for by having your pickup closer to said string. By backing yours all the way off you may have unintentionally exacerbated the issue...or not...
Again, not being able to physically touch the guitar makes all of this somewhat academic.
Sounds like you need to find a good tech and just have this guitar looked at. There has to be someone over there that can do this. Even if it's a fast $50.00 you really need a good reference where things are right and where they're wrong.
Good luck...we're all pulling for you.
HTC1
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Post by Deleted on Feb 3, 2015 3:18:28 GMT -5
Hey thanx for you info John and Cyn1. Yesterday I tried : - unscrewing a little bit the two right screws - removing the shim - setup again and again
And I concluded that : on 22nd fret -> 24th fret, on high E , the guitar simply does not want to sustain, I get 4 seconds max, if I am lucky, which in it self is not so bad, right?
Maybe it has to do with basswood. On last frets, the mapple/walnut/maple/walnut/maple (neck woods) maybe do not help resonate but rely on basswood instead. Maybe it is the turss rod and the two titanium rods underneath, I do not know.
John's idea is a valid one, but applies to all adjacent frets. Why e.g. do I have 5 full seconds on 17th fret even 20th fret, and an equally loud a bright first 3 seconds on 22nd fret, but having it decay sharply and die out instantly ?
Cyn1, I experimented with all combinations of string action heights and pickup heights, did not make any substantial difference. Always the note on 22th fret would die noticeably sooner than than on the 20th. IMHO, and taking into account John's ideas above, in a situation when the note starts loudly, and then decays a little, then it goes slightly strong again, but then dies sharply I think this is due to the very nature of the materials and parts and nothing can be done to correct this, at least in a non-intrusive manner.
Anyways, I am sorry, I might have gotten into paranoia mode again, maybe I find this as a cheap method for self therapy instead of paying high grand to the psychotherapist, but I surely need to start producing useful music with this thing instead of chasing ghosts.
Cyn1, about getting my guitar to a tech, to be frank, I cannot imagine what he can do, that i can't. Most of them do not even listen when you talk. I think the guitar has reached its maximal performance and any further alterations will do only harm.
Thanx a lot for your very useful info, and sorry for taking up your valuable time!
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Post by cynical1 on Feb 5, 2015 1:12:32 GMT -5
If my time was valuable you'd have gotten a bill already.
If I was to put $5.00 on it I'd bet you've got a high fret somewhere. Try a short straight edge, like a credit card, and see if it rocks on any frets. Very common issue on the higher frets.
And taking it to a good guitar tech to look it over was not meant as a slight. Hell, I've taken guitars to other techs when I just hit a mental block, or knew they had better tools and measuring devices than I had.
HTC1
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Post by Deleted on Feb 5, 2015 4:17:12 GMT -5
If my time was valuable you'd have gotten a bill already. If I was to put $5.00 on it I'd bet you've got a high fret somewhere. Try a short straight edge, like a credit card, and see if it rocks on any frets. Very common issue on the higher frets. And taking it to a good guitar tech to look it over was not meant as a slight. Hell, I've taken guitars to other techs when I just hit a mental block, or knew they had better tools and measuring devices than I had. HTC1 I had checked all that. Instead of a credit card I tend to use various edges or various sizes alen keys, and look for audible and sensible knocking. If the knocking is not heard between 3 frets and is heard when I move one fret left or right, I know I have a high spot. This is not the case here, and also the problem gets worse on 24th fret. While this guitar sustains equally or better than maybe all my other guitars, in 24th fret I get better sustain with all my other 24 fret guitars than with this one. All I can do is live with it, it is not the end of the world! If accidentally anything gets better on the long run, e.g by changing string brand, then all good, otherwise I guess it is little I can do.
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Post by Deleted on Feb 6, 2015 11:15:27 GMT -5
I found this article by frudua : www.frudua.com/sound_of_electric_guitar_wood.htm which goes along the lines of the principles that John explained above. I think my problem is that from 22nd fret to the 24th, the neck (5pc maple/wenge/maple/wenge/maple) does not have any effect on the resonance, while basswood by itself cannot resonate those frequencies, hence this effect. It seems this is natural.
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Post by cynical1 on Feb 6, 2015 15:14:42 GMT -5
This is really a guide to the "coloration" different woods contribute\diminish\accentuate to the overall tone. It's not the answer to the dead note issue.
I would suspect it's something mechanical versus intrinsic.
HTC1
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Post by Deleted on Feb 7, 2015 0:30:02 GMT -5
Good morning Cyn1, I did some tests on sustain on Carvin and on the Ibanez : Carvin DC135 : 24.75" , hard maple neck trhough, hard maple wings (most propably), 24 frets, OFR bridge, Gotoh nut, DImarzio super distortion, empty, air norton S Ibanez UV70p : 25.5", Wizard-7 5-piece maple/walnut neck, basswood body, 24 frets, edge zero ii-7, ibanez nut, Dimarzio blaze : bridge, middle, neck. Overall both guitars sustain well. On the lower part of the fretboard (left side), I think Ibanez sustains just a little better. On the high frets 12-20, they are equal. On 22nd fret, the Carvin wins hands down. On the carvin I got sustain 5 seconds on D (high E 22nd fret), without the amp, and about 10+ seconds or more with a little help of the amp feedback. On the uv70p, i cannot make the same fret D (high E 22nd fret) ring for so long, no matter what. I get 4 seconds max. Not a big problem, I was just thinking about it. Now, the same note is produced by the pinch/natural harmonic on 3rd string 3rd fret, it is exactly the same frequency. Now hold tight!!! When played as an harmonic on the 3rd string 3rd fret, the sustain is better on the ibanez!!! (Carvin struggles to hold the note) When played as a freted note on the 1st string 22nd fret, the sustain is better on the Carvin!!! (Ibanez struggles to hold the note) In the meantime, the Carvin, *always* kicked some butt in the harmonics high on the fretboard on high strings (yes even high E)! What I get : While we play, not on last frets : e.g open->20th , then neck wood takes most of the responsibility of resonating the note. When we play from 20-24th, then the body takes that responsibility. Now, the Carvin, being a hard maple neck , resonate some frequencies differently than the ibanez which is maple/walnut, maybe the Ibanez can do some mid/high-range natural harmonics better on the left side (longer string lengths) of the fretboard, that's why the natural harmonic sounds better on the Ibanez. I had learned this harmonic from my Kramer, which literally can sustain this note for days. It is also mid-range-y as well as the Ibanez. Now on the 22nd fret, the neck maybe gets out of the equation, and it is the body doing its work now (as frudua says here : www.frudua.com/neck_influence_in_guitar_tone.htm ). Now, the basswood body simply cannot resonate this frequency at this string length (shorter string lengths) while the maple does this very well. EDIT : this last should be, "the basswood body resonates at a very similar frequency, cancelling each other out" Now about the mechanical explanation, as you may remember, I have been obsessed with buzz for quite some time, starting with the first Ibanez and its low E. I am not the kind of player who would live with buzz and choked notes. If the problem was buzz I would have dealt with it. There is no buzz, 20th fret does 5 seconds with no amp no feedback, and on 24th fret drops to barely 2-3. Also the pattern of the fade out is like : strong -> weak -> instantly strong -> sudden death. It is some opposing (same? ) frequency that is killing it. I checked for bridge vibrations, saddle vibrations, I silenced the trem springs, there is no indication of mechanical malfunction, otherwise the problem might affect other notes as well, not just the last 3 frets. I know this goes against the school of GN2 which promotes the "electrical signal" over all theory, but I start to believe woods are the most important. At least comparison of those two guitars drives me to believe so. I tend to believe this has to do with the frequencies, the string lengths, and the medium involved (maple, basswood, nickel, zinc). Fine tuning all those parameters is what gives a good instrument. I think blindly choosing materials (like I did in my non-sustaining partscaster) won't result in a tone rich instrument. Comparing my strat, kramer, carvin and the two ibanezes (the second ibanez ARZ800 is all Mahogany neck/body and rosewood fretboard), i tend to believe that a good instrument can do *many* notes well, maybe not all but most. Instruments with dead notes in crucial "popular" regions of the fretboard are IMO examples of bad wood selection and/or combination. For me, metal hardware never played much in all this. My partscaster's sustain sucked no matter the upgardes, the pups, the super-vee's. My traditional old good Aria strat, which I have since I was still in school, sustains no matter the bridge, the headers it has taken all those years, all the problems i caused on the wood (but later fixed). I can't get it to not sustain! I believe if an instrument is good at the vast majority of missions it will undertake, then it is a keeper, otherwise not so much. this epiphone with the long sustain on *this* note apparently has some difference in the woods, although sharing basically the same hardware with the rest of gibsons and epiphones. BTW My Ibby can do better than the second Gibson on this specific note, maybe close to the first one with some help of the amp (which i am not allowed to use very often)
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Post by reTrEaD on Feb 9, 2015 8:58:32 GMT -5
As I say, I'm just guessing here.. John, your guesses serve as great conversation starters. For a given damping %, every time the string goes through a cycle, it loses a certain small percentage of its energy. So, if high-fretted strings have the same % damping as low fretted ones, and if we pluck the strings with the same energy, the high fretted strings will go through more cycles quicker and hence decay quicker, all other things being equal. This follows a logical line of reasoning. There may be other factors working to mitigate this effect but I can't think of what they would be so I'll just leave that open for others to suggest. However, I do have some thoughts on another factor that might cause more decay on a shorter string. String stiffness. The middle of the string length experiences only slight angular deflection but as we approach the ends of the strings there is a region that sees a significant angular deflection that increases as we approach either endpoint. As I have learned, string stiffness is a factor in intonation correction. For strings of the same material and construction, the effect of this stiffness increases with diameter. Thus the bridge saddles on larger diameter strings need to be closer to the tail to compensate for intonation errors caused by this effect. Likewise, I suspect the stiffness and resistance to angular changes would be a fixed commodity in terms of decay. Longer strings would have a lower percentage of their overall length in the regions near the endpoints. Thus I reckon they would suffer from quicker decay. Looking at this from another point of view, a longer string would require less angular deflection at the endpoints to achieve the same physical displacement at the midpoint. So it would seem a shorter string would cause more energy to be dissipated by the work necessary to bend the stiff region at the ends, because of the greater angle necessary for the same physical displacement at the midpoint. My other thought is about the shape of frets to promote sustain. Fret profiles generally have rounded tops, as in cyn1's diagram above. When we press on the fret, we clamp the string down with enough pressure to stop it moving at the crown. No energy is lost there. Once it leaves the fret, again there is no interaction between fret and string. But Im thinking that the part of the fret where the crown is rolling away down to the fret board, will be a zone where pressure between string and fret is gradually reducing There will be a tiny zone, just before the string leaves the fret, where the pressure is low enough that there is not enough friction to lock the string to the fret. hence there will be some miniscule sliding of string against fret, resulting in friction, adding damping, reducing sustain. To address that, one would want the bridge side of each fret to be very steep, like a cliff rather than a hill so the string goes instantly from fully clamped down to completely free.. John, this is worthy of extended discussion. I had the same thought several years ago. I'm not certain whether the reason frets are the way they currently are simply because of tradition or if it's because "cliff" frets would be prone to causing other undesirable problems. Certainly the fret wear issue could easily be mitigated by more durable materials (stainless steel for instance). But there would be the problem of fret width when replacing frets. Currently the width of the fret is not an intonation issue with replacement frets because the high point after crowning is dead-center. However as the fret wears, the intonation does tend to go slightly sharp as the crowned area becomes more flat. If the cliff frets were designed so the cliff was directly over the centerline of the fret slot, they could be a direct replacement for crowned frets. Fret width would never be an issue. But if the cliffs were toward the bridge edge of the fret, relative to the fret slot centerline, the placement of the fretslots would need to be offset toward the nut from their current location. Additionally, a standard width would be necessary, else the cliffs on wider frets would be too close to the bridge and narrower frets would have the cliffs too far from the bridge. Even with standardization, I'm concerned there might be another problem caused by cliff frets. Have you ever noticed the dents on a used string caused by the frets? To a small degree, I think they might cause a loss of sustain. But to a much larger degree I think this is a major cause of used strings having poor harmonic content, causing them to sound dull and lifeless. I suspect cliff frets would be likely to cause dents/wear at a faster rate. How much faster? I wouldn't begin to guess. If only slight, it wouldn't negate a substantial improvement in sustain. Even considering the possible drawbacks, cliff frets do seem worthy of evaluation. Unfortunately prototyping them would beyond the realm of most DIY guys.
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Post by Deleted on Feb 9, 2015 11:17:06 GMT -5
A fellow Ibanez player sent me this :
And my reply :
In my experience when this "wave interference" happens the note at this fret will not have sustain. IMO might not be accurate to say that higher fretted notes should not sustain for long. Given a fret (lower part on the fretboard) we might construct a guitar whose materials (woods) simply resonate at double this frequency killing the fundamental note early, while e.g. same note one octave higher will not be be affected, since the two signals will never meet. This is manifested by the Carvin, which sensing the same note on 3rd fret produces short death while on 22th note long sustain. If there are no opposing frequencies that travel inside the wood and back to the strings, or when the least common multitude of the periods happen at a much later value than each individual period, the note will have a long sustain. This explains why D played in one case on high E 22nd fret, and on the other case as a natural harmonic on G 3rd fret , has such a dramatic difference in performance between the all maple Carvin and the maple/walnut/basswood ibanez. Ibanez sustains longer the natural harmonic version while Carvin the 22nd fret version.
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Post by Deleted on Feb 10, 2015 1:50:50 GMT -5
IMO might not be accurate to say that higher fretted notes should not sustain for long. For those of you with an all mahogany guitar (e.g. SG, but its only a speculation). you might want to try this test : Measure the sustain of : a) G 12th fret b) G 14th fret (A) c) G 14th fret bended a full tone (B) d) G 16th fret (B) Do you notice any differences in sustain? In my single cut Ibanez ARZ800 the difference between a) and c) is dramatic. The c) is the same note benchmarked by the two british guys in the video i posted above. ARZ800 seems to do slightly better than the longest sustaining LP in the above video (with the help of the amp). Also google for people having troubles with a) on Gibson SGs on G 12th fret. I am sure that if the guitar woods *want* to cancel a frequency, then they will find a way to do so, no matter the fancy hardware upgrades or ultra precision fretwork done. So it is pointless to discuss about theories (string stiffness) that would explain why shorter strings sustain shorter than longer strings, if the very hypothesis is (by experiment proven) wrong.
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Post by lunaalta on Feb 10, 2015 10:44:00 GMT -5
I just found this pdf of experiments done by the Institute of Mechanics, Faculty of Aerospace Engineering at the University of The Federal Armed Forces in Germany. Why, exactly, they would be studying guitar string vibrations,, in the military aerospace department, completely baffles me, but then, that's not hard to do.... LOL Guitar string deadspotsMaybe not totally on topic, but I think it might add food for further thought to this fascinating thread..... Isn't the foto from the scanning vibrometer amazing? The info in this report kind of leads to the probability of 'changes' to string vibration properties as the string is fretted higher up the neck, due to the amount of neck which is, consequently, left out of the 'direct' resonance circuit. I think.....
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Post by Deleted on Feb 10, 2015 13:03:57 GMT -5
Hola!!! Great find Luna! The info in this report kind of leads to the probability of 'changes' to string vibration properties as the string is fretted higher up the neck, due to the amount of neck which is, consequently, left out of the 'direct' resonance circuit. Bingo! Now on the 22nd fret, the neck maybe gets out of the equation, and it is the body doing its work now That's why Gibson thought of the maple top on their bodies!
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Post by lunaalta on Feb 10, 2015 13:33:33 GMT -5
Yassoo, GD! Now, if only NASA would do some research on this we might get even further.....
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Post by Deleted on Feb 10, 2015 13:52:55 GMT -5
Yassoo, GD! Now, if only NASA would do some research on this we might get even further..... Seriously, I think *every* guitar should come with a similar "conductance" chart str8 from the factory. So that the buyer knows what to expect! All this basswood/alder/maple/mahogany/walnut/wenge/bubinga/rosewood talk is like geting a new car with e.g. a 2.0lt turbo engine, and then googling to find smth like " turbo cars tend to be faster than N/A ones, also larger displacement helps"... Wouldn't it suck? The buyer needs to know exactly how a machinery/device works.
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Post by haydukej on Feb 10, 2015 14:33:07 GMT -5
I'm not sure I entirely understand that whole article provided by the Federal Armed Forces, so naturally, I provide some criticism of it. - Only four pages! This makes me highly suspicious that it's actually from a government agency.
- I tend to think of acoustic instruments being designed to "resonate" while solid-body electrics are designed to minimize resonance, which might induce feedback. But maybe I'm blurring the lines of resonance vs. sustain. Our archtop semi-hollow bodies try to make the best of both worlds, eh?
- Quote on Page 2 of the paper. Resonances of the instrument are supposed to cause dead spots By that definition, wouldn't an acoustic be completely dead?
- Who wouldn't mind a strat painted like the one in Figure 1?
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Post by JohnH on Feb 10, 2015 15:22:14 GMT -5
I think that university paper was very interesting. It made me think of another thing relevant to dynamics issues in my day job.
In floors that are too bouncy, and tall buildings that sway uncomfortably at a certain frequency, we sometimes seek to create an intentional 'dead spot' using a 'tuned mass damper' TMD. Its usually a mass, on a spring, with a damper element like a cars shock absorber. At the particular troublesome frequency, the mass starts to oscillate on the spring with a large movement. This sucks vibrational energy out if the main structure, which gets dissipated in the damper, reducing building vibration.
Here's the guitar analogy: The neck and body have their own vibrational modes, and they will vibrate at these frequencies taking energy from the strings. But wood, and anything in contact with a soft body (even one from the German army) will have much higher damping than a steel string vibration. Hence at the modal frequencies of the neck/body, there will be hugher damping and so less sustain.
Knowing that, does it lead to any solutions? Stiffer materials will help because they will move less,transfering less vibration and having less damping themselves. Adding mass strategically to the neck will change the response, for better or worse ie shift the dead spot which might help if you can shift it away from a note by half a semitone
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Post by Deleted on Feb 11, 2015 6:22:48 GMT -5
Here's the guitar analogy: The neck and body have their own vibrational modes, and they will vibrate at these frequencies taking energy from the strings. But wood, and anything in contact with a soft body (even one from the German army) will have much higher damping than a steel string vibration. Hence at the modal frequencies of the neck/body, there will be hugher damping and so less sustain. IMO loss of sustain is not so much affected simply by wood vibrations in the general sense, but particularly by those higher frequency vibrations which travel through the medium and come back and kill the fundamental string vibration. So at least to my ears, this is not simple damping, but explicit cancelation. I stopped with physics somewhere after Haliday Resnik II in 1st year at the Univ, so I am not the most appropriate person here to make suggestions, and I dont know if this is correct, John you might want to correct me here : Do stiffer and rigid materials resonate at higher frequencies? Cause if my theory is correct, we would want the material to resonate at much lower frequencies. So, that if we strum high E, fret e.g. 22nd, there will be many repetitions until the body vibration starts to change direction and go against the string. I dont know if this is possible and what would it mean practically. Another option would be ultra rigid body (and/or neck) which (is this true???) vibrate at a much higher frequency but absorbs tiny amounts of energy, so that there is nothing powerful to fight against the string's vibration.
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Post by Deleted on Feb 11, 2015 13:05:47 GMT -5
Just played the ARZ800 (mahogany, maple top) and the UV70p maple/walnut neck, basswood body , (kind of) loud with the amp, with the vol set about 1/4. What I noticed : - both guitars sustained for as long as i wanted G fret 7 bended a full tone (E) - ARZ800 sustained infinitely G 14 fret, bended a full tone (B) - UV70p sustained infinitely high E 17th fret (A)!!!!! which is very very nice!!
What I get : when the guitar "wants" and I mean that when it exhibits higher sustain with no amp feedback, it will sustain indefinitely with the help of the amp. Otherwise ... umhh I don't know I gotta try with higher volumes, when wife approves.
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