Overlayed bridge plate, effect tone...?

[Allan Lang]

Hi everyone,

I have an older, 1974 Alvarez Yairi DY-77, a nice guitar. The typical chipping on the bridge plate had occurred over  time and the string ends were starting to cut up into the plate. Rather than replace the plate as it was not warped, cracked and in good shape except the widen pin holes I decided to do an overlay with a piece of maple. Of course I'm a fan of running the grain of the overlay with the top, like Frank would have.

All worked out well for the repair that is except I feel that the guitar sounds like a blanket is covering it when playing, there seems to be a loss of high end cut. The bass is there, so are the mids but the high end seems to suffer...? Could this overlay be causing the problem? The original plate was rosewood about 3/32" thick and the maple overlay is 3/32" also. The original plate was rather wide, 3" my overlay was narrower, an 1 1/4" at most. I was thinking of removing the overlay and filling the chips with something...? And drilling the holes with a hardwood backer. This is a lot of work on a not so valuable guitar and unless I "knew" this was the cause of the weak top end cut, not worth the effort..?

Unfortunately, I repaired the guitar when I first got it without playing it much and don't know if the weak top end cut was there or not before the repair. I'm going my my experience. The guitar is aged spruce, 38 years aged with a Brazilian Rosewood laminated back and sides. The DY77 was a nicely made copy of a D28 by Yairi.

Any advice, greatly appreciate,

Al Lang, Philadelphia

[Hesh Breakstone]

Hi Al.  I try to avoid conversations about things as subjective as tone but if you wanna go there I can give you my two cents, pardon the pun... worth.

First though the way that we make our bridge plate "caps" is to make them only large enough to provide a solid surface for the string balls.  This means that my bridge plate caps may only be 1/4" longer on each end than the pin hole spacing and only 1/2" wide.  We don't use caps as a reinforcement for other bridge plate or top issues.  Instead and again it's only large enough to have a solid surface for the string balls to rest on.

Typical thickness is .060" and with absolutely no disrespect intended to our friend and host Frank, ever, my caps are typically flat or rift sawn.  In our case with the caps so very small grain direction would only impact an area 1/2" wide so what's the point?

Now if you do the math our caps are likely around one third the mass of your cap as per your description.  As such, and again this is subjective as can be, any potential impact on that four letter word.... tone, is minimal to possibly nonexistent.  Additionally all edges of the cap are beveled as well.

Regarding the loss or possible loss of highs since you did not play the ax prior to the repair how would you know?  It could be that this is simply what it is and that the highs are not what we would want on this guitar.  It does have laminated sides and was never a high-end instrument.

Other possibilities if the trebles are not all that they could be are to numerous to list but on a guitar this age the break angle over a possibly shaved saddle (and/or bridge) may not be all that.  It very likely has had some movement in the upper bout over time and string tension so it's possible that others have worked on it prior and that the break angle on the high e and b suck.

Back to the caps - we have seen rather massive caps or the doubling of the bridge plates and it's likely that when this much additional mass is introduced with no increase in string energy that one "may" be able to hear a difference but again it's always a very subjective topic, tone.

I hope this helps.

[Allan Lang]

Thank you for replying Hesh, your comments all make sense. I had reset the neck when I got it, luckily the bridge was never touched, full 5/16" thick and a little more, with the neck set the saddle height is very good. BTW, I changed the dovetail set to a bolt-on. Worked out pretty well, I just copied Taylor's method with a couple of bushings, I was able to adjust the angle after the original set this way, no guessing.

Anyway, upon further playing comparing to another great sounding Yairi (I love these guitars), I might be lacking volume rather than high end. I took the saddle out, the slot is too shallow, slightly less than half the saddle is in the bridge and it's tilting forward. Also, worst than that the slot bottom is not flat, it dips in the middle leaving a hollow spot. I now think this is where I'm losing tone or volume as the D and G strings are much lower in volume (where the dip is). I need to deepen the slot and square it up. I have never done this but read about the dremel tool. I have a small hand held router but with my experience, I can't see how I could make it deeper and square without some kind of jig. I am a cabinet maker by trade and very familiar with router use. The top of the bridge is not parallel to the guitar's top, of course so I can't ride the router on the top of the bridge.

Any info on how this is done? Also any free hand use would tear up the slot, am I right? I can make another saddle if the slot becomes slightly wider. The guitar's intonation is slightly sharp so if I widen the slot toward the peg head (slightly) I just might solve this too. Probably the reset brought the neck in a little bit, were not talking much here, maybe .020 at most. Although the guitar plays well as is, just weak volume.

I think this is my problem, weak volume from poorly fitted saddle and bridge slot. Steer me in the right direction, I'm very good with router use. I would think a jig siting on top of the guitar parallel to the slots bottom and a guide for the router would be the answer..?

Thanks,

al

[Hesh Breakstone]

Al it sounds like you are doing some really nice work on that old girl!

Here is a link to a recent and very good thread on slotting bridges, jigs, etc:  slotting jigs  Hopefully this will be helpful to you.

You are on the right track in terms of routing the slot to have a level bottom and while you are at it to improve the range of adjustment for proper intonation.  You are also correct that free handing this operation, at least if I did it.... would not be pretty.  But the link I believe if I recall correctly has some very decent jigs that are not difficult to make and you my friend might just come up with something else too that works great once you see what others are doing.

Regarding the intonation I may have misread your post but if the string is sharp you make it longer.  Moving the break on the saddle toward the peg head would make it shorter.  So if the intonation is sharp you want to shave the side of the saddle slot while truing it up on the bridge pin side not the sound hole side of the slot.  An unintended benefit would also increase the break angle.

And right you are that a saddle bottom that is not level and even has places where the saddle is not in contact with the bottom of the slot can produce less volume.

By the way resetting and converting a neck on one of these to a Taylor bolt-on style is pretty impressive!  It's not the kind of thing that we often read that someone who is not in the biz attempts so my hats off to you!

Regarding router or Dremel or other less-than-router tools you will see a pretty good discussion in the linked thread.  We use the old-trusty Porter Cable PC-310 laminate trimmer that is now sadly discontinued.  It is the very best laminate trimmer that I have ever used and they can be brought back to life when need be with bearing replacements.  A full sized router may be over kill but you may have a laminate trimmer and my guess is that you likely do.

Keep up the great work!!

[Allan Lang]

Thanks, for the link and yes I have a small hand held router.

"Regarding the intonation I may have misread your post but if the string is sharp you make it longer.  Moving the break on the saddle toward the peg head would make it shorter.  So if the intonation is sharp you want to shave the side of the saddle slot while truing it up on the bridge pin side not the sound hole side of the slot.  An unintended benefit would also increase the break angle."

Yes, I had the right side in my mind but wrote peg-head and really meant end pin, or pins.

I just might manually try to lower the slot depth and square it up. To check on my progress I could use wax paper in the slot and use auto-body filler - pushed in. When it hardens I could take it out easily and check for squareness and a flat bottom. Or make a jig. The only thing is I wouldn't want to practice on this guitar so I thought I'd could try manually first. It doesn't have to 100% perfect a few thousands off is better than the dip I have now, 1/32".

These early DY77's are great guitars, this one is kind of a beater but I love the way they play and sound. Crosby Stills & Nash used these models in the Seventies. Unfortunately, most of the 30 plus year old good Japanese guitars have high action due to years of pull and need neck resets. It's very difficult to get those necks off with the glue and poly they used then. I always see some great old Takamines S360's and S340's on flea-bay but always afraid of the dreaded old guitar high action and need of a neck reset.

Thanks, for all the posts guys and happy guitar making, fixing and repairing.

al 

[Mike Kolb]

Hi Allan...  last year I scored a couple of specialty files from StewMac for the express purpose of flattening the bottoms of the saddle slots.  

http://www.stewmac.com/shop/Tools/Special_tools_for_Bridges/Saddle_...

Here's a tip: when the guitar's strung-up to pitch, measure the rise/bellying of the top. Then duplicate that amount of rise with a small jack inside the body before flattening the saddle slot. 

[Allan Lang]

Thanks Mike

I think I can make something like that in my shop, I have a lot of aluminum straight edges laying around, I could make teeth or even glue a piece of sandpaper on the bottom. Since I'd only use it once or twice might be a good solution, I had been thinking about how I was going manually square it up, thanks again.

al

[Ned Knepp]

Allan, something you mentioned earlier may come into play with the intonation and I haven't seen it mentioned again. 

 You said that the saddle is leaning forward. You didn't mention how much or how far sharp the guitar is playing but I think I would see about shimming the bridge to vertical and testing the intonation before I started removing material from the slot to move it. It may be that lowering the saddle enough to flatten the bottom of the slot AND straightening the saddle to vertical may eliminate your intonation issue since it will lengthening the strings and reducing the amount of stretch as you hold them at the same time.

[Allan Lang]

Ned,  boy you're on top of on the situation, good one. You are so correct. "From my experience" the lean is not that much, an estimate between the saddle completely vertical and the now lean is about "15 cent" in intonation, I'm out about about 30 cent sharp, so I don't need much shaved on the back side of the slot. Usually a new saddle comes thick enough to work in a slightly wider width slot.  On a martin style saddle which is what I have the top can be filed forward or backward to get a few cents there or there, much easier to do on a wider saddle thought. But your right I'll wedge the saddle straight first and check, only takes an extra string-up.

It's always a drag when we do things like this and one of the old set of strings breaks before we get to test things out, I just hate that. I use Elixir's Polyweb, they last so long, although I love the brightness of a new set of regular D'Addario's.

Thanks for the follow-up,

al

[Ned Knepp]

I think that Hesh has the right idea. I am writing because I have some experience with Yairi  guitars and own a Dy-75 that I bought new in early 1981. It and every Yairi guitar I've played is, to my ear, weak on bass and I've talked to many others people that agree. It seem to be one of the attributes that these guitars share so if you are loosing the treble side I would guess that there is something amiss.

 Like Hesh pointed out there could be other thing wrong but I don't think these would respond well to a heavy bridge plate so you may need to make an adjustment there before you do anything else.

BTW, the weak bass response on these guitars may be an indication of the bracing which might be just a touch heavy, My guitar was setup at the shop when I purchased and it never needed any adjustments to it since. I have other guitars that are newer that have all needed some adjustments to the action at least once but this one is still just as it came to me. It's also the easiest playing steel string acoustic I've ever played.  I just wished it boomed a bit more.  

[Hesh Breakstone]

Hi Ned!  I've always been a huge fan of the Yairi guitars too and I completely agree with your excellent assessment on the characteristics of how they sound.

We've also seen pretty old ones that still are not distorting on the upper bout or needing a neck reset.  Great guitars and pretty good looking too!

[Ned Knepp]

I don't play mine too often anymore but keep it around because it so easy to play and it sounds great unless you like more base, which I do. It's not bad, just not balanced. Mids and trebles are very nice but I find that I push trying to get bass to match them. If it were not for that, many of these would match guitars selling for two or three times their price. Even with this small deficit,  I think they are one of the better values in vintage guitars available today.

I considered shaving a bit from the bracing on the bass side to see if it would help but realized that it would be silly to do so. First of all, it not easily reversed and, secondly, if it was such a problem for me I should just sell it to someone that appreciated it as it is and buy something that gives me what I want. Obviously it's not that much of a problem since I still own and play it.  Beside, I have other guitars that boom bass. 

[Scott Supak]

Hi Guys,

Not to hijack this thread, but could anyone please give some insight as to what the neck joint is like to get apart on these?

I've got a real clean/original owner DY77 in the shop that needs the neck set or...

They are decent guitars all in all, but that is pretty thick poly all over the heel.

 

Thanks!

Scott