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Hi All:

When playing some slack key (open tuning) pieces that require hammer-on and pull offs on upper frets (7, 9, and 12) I get string noise from the string hitting the lower frets during the hammer-on. I have tested a variety of nylon-string and steel-string guitars, some built by me and some by others and regardless of the action all make the same noise. Action on the tested guitars ranges from low to medium high at the nut.

I am thinking that if I raise the action at the nut it might solve the problem but will it leave the action pretty high overall and make playing harder? I suppose I could make a nut with high action on only the top string but this seems pretty strange.

Thanks in advance for your ideas.

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GEO
perpetual beginner

So I gather the guitars you have worked with were initially set-up for standard tuning. As you de-tune the strings to lower tension you dramatically change the sign wave of the string at a given position. Raising the saddle will have more affect on clearing frets 12-20 and less affect on 1-11. Raising the nut has more affect on clearing frets 1-11 and less on 12-20 . If one knows that an instrument will be played at a specific slack tuning it is always a good idea to have both the action and intonation set-up for the specific tuning and attack to be used.

This is on reason many performers have many guitaars during a performance. (set-up for different tunings)

While the string height will increased with this new action and se-up it should not be much noticable harder to play because the string tension has changed. Remember we are talking a few thousants to ten thousants here not a few 32nds.

Sounds like you are getting a sympathetic resonation in the string behind where you are fretting. This is especially common at the frets you are talking about.
I would
-Check that the relief in the neck is slill ok at the reduced tension of the open tuning
-Live with it
-Don't compromise your overall setup to resolve this

Michael and Jeff:

Thanks for the input. Since the guitar in question is nylon string the action is typical. It is about 1mm gap at the first fret for both strings 1 and 6. At the 12th fret it is 2.5mm for the 1st string and 3.5mm for the 6th string. The tuning -taro patch - or open G (DGDGBD) has three strings slacked. I am using high tension strings because they sound better with this guitar so tension-wise there is not much change.

I think the plan is to gradually shim up the nut until the extra sounds go away. Then see if the guitar is playable. If so then make a new nut to the better height. If not, I can live with the noise on some songs but there are a couple songs with lots of hammer-on and pull-offs on higher frets that just do not sound right so they may go away.

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GEO
perpetual beginner

George, if you are an experienced player, you already know this, so disregard this comment...

You will get a much cleaner sound if you hammer (and fret in general) immediately behind the fret - almost on top of it. Fingering/hammering further back in the space between the frets is inviting noise and other problems. With precise fingering, you can also fret/hammer with a lot less force, which will further reduce unwanted string noise and spare your fingers and your fretboard.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

Hi George,
I'm not an expert, but have you tried loosening the truss rod to compensate for the lower string tension?
Not sure if you'd get much change down in the lower frets.

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Horton, MI

I'm no expert here, but 2.5mm and 3.5mm at 12 sounds like pretty low action for a nylon strung guitar, to me. Standard is closer to 3.0 and 4.0. Not saying you can't have it at the lower level, but that's not giving those floppy strings much room to move at standard tuning. Then you drop tune it? You would have to have a lot of relief in the board. Also, if you have 1mm at the first fret, I don't think you need to shim the nut. That's not where your problem is. Clearance at the first, even on a classical, can be low enough to clear a piece of paper with the string fretted at the 3rd. That leaves the open clearance at the first at about .5mm +/- .1 or so.

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Waddy

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Hi:

Again, thanks for the input and ideas.

Todd: Good point about technique. I have tried to work out technical issues with the hammer-ons and tried left hand finger placement and pressure adjustsments without success, hence the question about action possibilities.

Kirt: As general rule there is no truss rod in the classical guitars but never say never. One local classical builder has put in at truss rod at the request of a jazz guitarist for a nylon strung guitar. Generally for classicals the string tension will put a little relief on the fingerboard, if it not already put in while shaping it.

Waddy: I am certainly no expert either. What I have done for the guitars I have built is start with what the books (Courtnall and Cumpiano) recommend for action levels and then have local classical players try them out. They almost always ask for lower action. So far I have been able to do that without string buzzes or fret noise using standard tuning and normal tension strings. But then those folks play the usual classical repetiore not Hawaiian slack key so usually do not have to deal with hammer ons on the higher frets. I guess here is another example of never say never, but at least I do not recall noticing hammer ons on the higher frets used by performers at the local classical guitar society.

If I am able to get rid of the noise (actually a high pitched note) from the strings hitting the frets below the fretted note, then I will report back on playability.

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GEO
perpetual beginner

Actually there are many examples of more modern classical play using hammer-ons, slides and pull offs. off the top of my head Classical Gas comes to mind and the intro to Roundabout played on classical by Steve How.

In regards to detuning and classical play, Michael Chapdelaine once told me that he commonly plays classical pieces in drop tunings.

Oops, your right, I passed right over where you said nylon strings. No wonder nobody mentioned it.

good luck

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Horton, MI

Hi:

Michael you are right of course. There are lots of hammer ons, pull offs and percussive things in guitar music we hear today. I did hear Badi Assad a few years ago and she played lots of percussive things on her guitar and parts of her body too. I did hear a great program by MIchael Chapdelaine a few months ago. It seems he has switched to steel string guitars but did include an Albeniz piece in the program.

Your comments suggest to me that I need to check in with some more experienced players in solving the string noise. The best local player is likely at the GFA meeting this week so I will experiment with nut and saddle adjustments until I can check with him. Thanks.

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GEO
perpetual beginner

It may be something that is more evident to you as the player as it is happening right near your ear but not being amplified by the body of the guitar as it is isolated by the fretting finger and frets.
Having a higher saddle will certainly NOT help
A Higher nut may make some difference but at a cost of general playability.

Hi:

Jeff: I had hoped it was the case that the extra note would not be heard but then I played the piece for a friend - an experienced musician - and he picked up on it right away.

As I consider myself a novice builder, this is a chance for a learning experience. Trying lots of different things might be useful. So far I have raised the nut by 1mm and in looking at the 1st string while fretted at the 12th, the string no longer touches the lower frets. It is still touches fret thirteen and fourteen hence my interest in looking at the saddle as well. I guess I can always string it up again and recheck for string caused neck relief.

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GEO
perpetual beginner

Raising the nut, not the saddle would have no affect or change on a fretted string forward of the fretted position. If the buzz is happening between the fretted position and the saddle then the saddle or fret heights beyond the fretted position are the only heights that come into play as long as the what is happing is not a sympathetic note from another string. I think you have already ruled that out.

This is why i said early in this post that you may want to do a full setup on this guitar to account for your desired attack and drop tuning. But of course this pretty much dedicates this guitar to your drop tuning.

it is kind of a catch 22 with loose strings. the amount of oscillation travel increases with lack of tension. So a set-up that accounts for the tuning plays best in this tuning. While you can split hairs on this. Everything I read tells me this guitar was set up for low action/ standard tuning. And there is the possibility that the action was not checked all the way through the scale in the original set-up and may have played fine standard tuning frets 1-12 but might have buzzed if played much beyond 12. in other words if in standard tuning the strings played well in all fretted positions 1-12 with normal attack why mess with the frets 13-19. I have seen this before on some classicals. Then when you slack the tension the problem shows its ugly head. This can be created both by the attack and larger sign wave of the string.

Keep in mid that since you have raised the nut you have raised the action the most on the nut end and very little at 12 and beyond. When you now rise the saddle you will raise the other end of this plane the over all action will rise more from where it is not with the greatest percentage of new rise towards the saddle.

Michael:

Obviously there is lots I need to learn and I very much appreciate you sharing your experience. I did plan for this guitar to be for slack key use, mainly open G. The initial set-up advice (apart from the books) came from two expert local classical builders, Dake Traphagen and Steve Ganz so the final action was based on their classical music experience. For five guitars I built since then when they see them I get the same advice - lower the action.

So for this one guitar and for a couple of songs, the action seems to be the problem. When I started looking at the cause for the noise I could see that if I pressed the first string at the 12th fret, the string was touching several of the lower frets and that is with fretboard relief. For this experiment I have raised the nut with brass shim stock and now if I (gently) fret at the 12th only the 11th fret has the string touching it. It is an improvement although things look pretty high. The action numbers now are 1st string at 1st fret = 2.1mm and 4.6mm at the 12th. For the 6th string it is 2.25mm at the first fret and 4.25mm at the 12th fret. No strings are touching above the fretted string. I am using high tension strings. None of my guitars so far, including this one have had any problems with buzzing in the upper fret range as a result of the local builder advice, all have relatively low action - if 3mm clearance of the 6th string at the 12th fret is considered low.

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GEO
perpetual beginner

Now I'm curious. How much forward pitch do you have on your neck? For instance, mine was about 2mm, and I have a 25' radius on the lower bout, but it also drops away due to the raised portion of the solera, which makes for a trade off on height of bridge and saddle. In addition to that, my fingerboard tapers from 7mm at the nut to 4mm at the 19th on the bass side and 5mm at 19 on the treble side. I can't remember what Cumpiano recommends, but I believe Courtnall says something like 2 or 3 mm.

Your present set-up with the shims sounds high, now, particularly on the lower frets. The forward angle of the neck, and the taper of the fingerboard should accommodate for the increasing distance from fret tops from 1 to 19, without having to be that high at the nut.

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Waddy

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George, this is a different scenario to what you described earlier.
If you are fretting at 12 and the string touches at 13 and 14 you may have fretboard or frets out of level and no amount of action adjustment at nut and saddle will rectify this .
Does the fretboard rise where it fixes to the body?
Check with a straightedge.
This would be so much easier with the instrument in hand

Scratching my head>>>> quite perplexed

What’s supposedly was happening before raising the nut
fret at 12--touch out at 13-14

What’s supposedly is happening after raising the nut
fret at 12—touch out at 11

This makes no practical since if no other change was made. once you fret the string you have mechanically eliminated the nut from the equation as far as how it affect the string height beyond the fretted position towards the saddle. If no other change was made you should be still touching out on 13 & 14. It could be possible that you touch out on 11 but after raising the nut you should have increased clearance between nut and fretted position not lowered it. Every thing you said in the last post is either backward or non-related to the mechanical reaction of raising the nut.

You did not raise the saddle so when you fret at 12 everything on the fretted string between fretted 12 and the saddle should be as it was in the beginning, before any change was made.

With the nut raised and saddle left as it was and fretted at 12 all the mechanical changes to that fretted string are between the nut and the fretted position. Raising the nut can not affect the plane of the fretted string beyond the fretted position if the saddle has remained in the original location.

Just not making since un less the neck is moving and even then it is not computing.

Please forgive me for asking, I am not trying to male fun of you or anything. Do you do agree that the saddle is on the bridge and nut is on the fretboard? Only reason I ask that question is because to add clearance at 13-&14 when fretted at 12 you need to raise the saddle not the nut.

I perceived that when "hammering" the string was hitting on the lower fret, which, in turn, was creating some peripheral string noise, not a part of the note. Maybe I'm reading wrong, but that's what I get from his post. I would also assume that by creating as much clearance in the lower frets, by raising the nut, there could be some issues with regard to intonation at 12.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

This is what I thought at first as well. Then he stated that after rasing the nut he touches out at 11 when fretting at 12 but cleared 13 and 14 (in regard to one string only). He then said before he raised the nut when fretting at 12 he touched at both 13 and 14. This seems very counter intuative. The change he made should have added clearance between the nut and fretted position, NOt between the fretted position and the saddle and certinly not lowerd the string plane between the nut and fretted position. this is indeed perplexing

In a word, Yep!

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Hi All:

My sincere apologies to all of you for causing lots of confusion. Part of it comes from my doing some checking of the action with only the top string on the guitar thus no neck relief. With all the strings on and tuned, the problem with frets above the one being fretted is not there.

Waddy: Neck angle on the solera is between 1.5 and 2mm as per the books. Not much FB taper on this guitar.

Jeff: I have now checked the fretboard both with and without strings. There does not seem to be any problem with high frets.

At this point I have a slightly better setup for one song but at the expense of pretty high action at the nut. As you will likely surmise, this makes some other songs especially those that have a full barre on the first or second frets unplayable. For one song the raising of the nut is not worth it so I will pull the shims and be back to the original normal action levels.

I hesitate to suggest any further experiments due to my lack of experience, but.....maybe a solution (again based on this experiment and only seven finished guitars) is perhaps build a new guitar with more fretboard relief for the top strings. I do not think I will pull the frets and try it on this guitar. The current fretboard relief is .007" at the 12th fret.

Just to check my sanity here, if you folks gently press the top string at the 12th fret of your steel string or nylon string guitars with normal actions, does the string stay clear of the 11th fret? Is it the same with a hammer-on? Is it the same result at the 9th or 14th fret?

Again, my apologies and thanks for your patience and for all the help. This continues to be quite a useful learning experience.

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GEO
perpetual beginner

George,
When you say that your neck relief at the 12th fret is .007 that concerns me.
You should measure relief by fretting the string at the first fret(a capo is useful here) and at the fret where the neck meets the body, going to the midpoint between (5th or 6th fret) and measuring the clearance from the string to the fret.

That's what I thought too. George, I checked my strings, and I have clearance on the frets below the fretted string as well as above. It's not much, but I can see light through the space. I didn't try to put a feeler in there, to check the height. My clearance at 5 or 6 when fretted at 1 and 12 is somewhere in the .2 mm range, it would appear.

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Waddy

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Sound Clips of most of my guitars