Another cedar top dud

hoji

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Second time building with a western red cedar top, and again disappointing results. The first time was a tenor a couple years ago, and is (I think) too thin, - loud, punchy, boomy, not much sustain. This time, a soprano, and I went a bit thicker (.075 - .08 inch). But this one sounds pretty bad as well - tinny, "poppy" like a banjo, and no depth. Tried all types of strings, nothing sounds good on it. My best guess is either it's too thick (the tinny, shallowness) or possibly under - braced ( the pop). What's the deal with this wood? Do you just have to brace it heavily to get it stiff enough? And thinner?
 
First of all, there is nothing wrong with WRC or its close relative, redwood as a top wood as far as those species are concerned. That said, whether the particular pieces of wood you used are lacking, I have no way of knowing. One thing I have learned in my many years of building, is that the material used in the nut, saddle and bridge, as well as the bridge design can have a huge effect on the sound of an instrument. You may wish to explore those further.
Brad
 
Hoji, I too have no way of knowing with any certainty what the problem is. In my collection of over 40 instruments which I have made, there are 2 tenors with WRC tops which are played daily because I love the warm sound that they produce: I like these better than my many Engelmann top instruments. You may be correct in thinking that your early tenor top was too thin but as you gain experience you should be able to produce a successful instrument with WRC.

The pros may have a better idea than me ( a hobby maker) but I dont brace WRC differently to other timbers. With a soprano theres always a tendency to overbrace leading to a very bright instrument: all thats needed is a 2mm bridge patch thinned at the edges and both ends. In general thick tops lead to lack of volume in my experience on all instruments.

You have no doubt read of makers flexing or tapping tops to determine whether they are of the correct stiffness. Others carry out deflection tests and over time have determined how this data informs them about the top's stiffness and likely tonal response.

I carry out some tapping and then trim the braces accordingly. I carry out a final 'test' as follows: I place a loose bridge on the surface of the soundboard of the completed box, first I press it down then I rock it side to side. I do this before the purfling and binding is done. This gives me an indication of whether the soundboard is too stiff. If necessary I will sand (some makers sand only around the edges of the lower bout).

I also tap and I believe I have some idea of how the box should sound (the tone lowers with material removal).

It should be apparent from the top distortion or lack of it whether your soundboards/bracing is too weak or too stiff. If your instruments are not too precious and have tops which are too thick or are overbraced, then you could risk trying to modify them. Its difficult but not impossible to thin the braces through the soundhole. Its also possible to thin the top (with or without bridge removal) and then refinish.

I suspect many of us prefer to keep instruments as wall hangers rather than trying to improve them. I think we find it easier to start again!

I would encourage you not to discard WRC. Many love WRC guitar and uke tops.
 
Thanks for all this advice. Oh, I'm not dogging WRC. I know it can be a great wood. I really want it to work for me. I just want to know what I've done wrong, so I can learn from mistakes. I'm at the trial and error stage of building, so I don't yet know how much flex is right, what the tap should sound like at certain stages.
Before I know these, I need to actually build a good one, right?

I hope I didn't come off as being negative towards the wood... it's my building abilities and lack of experience that frustrates me. Also, not having a master to guide and say " you left it too thick". Or "sounds like the top is too loose" is a disadvantage.
 
Hoji, as I said I too am a hobby builder but a little further along the road than you (6 yrs and 40+ instruments). We all suffer from working in isolation and can but try to find information on this forum, from books and from Youtube.

I have watched your builds to date with interest and can clearly see your enthusiasm and desire to make good instruments. My post is simply an attempt to try encourage you and others who are similarly on the road.

I have jumped about between lots of different instruments, all of my own design. It is probably better to stick to one design, carry out small changes from build to build and learn what works best for that instrument before trying a different instrument. As a hobby builder it doesnt really matter but as they say 'nothing breeds success like success': we all need to feel like are efforts are worthwhile.
 
I think the sound of this particular uke is caused by the top being too loose/flexible. I suspect under-bracing, not over-thinning. The bridge I used is quite small - 2.5 x .68, and just under .25 thick. (Sorry....inches 🙂), made of cherry. The bridge patch is just slightly larger, and very thin, basically a veneer, also of WRC. As a result, too much deflection, and hence the "banjo-like" pop/twang sound. So next time, I should use a more substantial bridge patch. One that is stiffer (maybe spruce), thicker in the middle and tapered off. Sound logical?

Also, does the thickness of the top I've used sound right? .075-.080? I know it depends on the piece of wood, and it's stiffness that matters more. But I think this should be the right range to start with, for WRC specifically.
 
Hoji, I've only made 5 or 6 sopranos, none with a softwood top. In mahogany or walnut the soundboard is 0.060". If I were to use softwood I would be starting at no more than 0.070" with a 0.080" patch and then seeing how it flexes and sounds when tapped. The patch is approx 5"x 3/4" thinned at the edge and ends and your bridge size is about right assuming its a little over 1/4" thick.

There are many on the forum with a lot more experience than me of making sopranos. Lets hope they jump in and offer their advice.
 
I think there are woods you can't build with no matter what you do. I can't work with maple or its equivalent sycamore. Move on and don't analyse it; you'll wast your life...
 
I've built 2 or 3 cedar topped sopranos which worked. Those tops were thicker but lightly braced.

I worry more about long grain flex than thickness. So I'll take the top down to around 0.1 inches and then flex it longitudinally, removing a little more until I like the feel. I'm looking for it to deflect a little under light thumb pressure if I hold it at either end. I don't expect to be able to deflect it more than about 0.25 inches without some effort.

There's a trade off between initial attack (which = perceived loudness) and sustain. Think of a banjo head, which give huge attack and little sustain. Too thick a wood top = dull and quiet. Somewhere in between is what is wanted.

But overall, I think you've gone too thin, not too thick.
 
At the very least I think you need to measure the density of the wood to know whether it is an average piece of WRC, or light, or heavy. From there you could choose to do deflection testing if some kind, either by feel, or using some science. But knowing the specific gravity of the wood you are working on is an absolute must for me.
 
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