After a too-long hiatus, I am about to start on several new builds. I've learned a lot from playing my previous builds as to what works well and what doesn't, and I'm hoping this new batch will benefit from previous mistakes, as well as experience.
I've definitely learned that leaving some space between the box (soundboard) and the through-neck makes for a much more acoustically resonant guitar and I plan to continue to build this way. However, on previous builds I didn't pay much attention to which side of the box I was using as a soundboard until I built one "backwards" (i.e., using the back of the box as the front of the guitar). In this case the back of the box was made of thinner wood. Quite happily this arrangement made for a much sharper and well-defined tone than my previous builds.
So my question is this: I am using a Don Pepin Garcia box for my newest project. I notice that the rear of the box is slightly thinner than the front. It also makes a cleaner *pop!* sound than the front when I tap on them. I am guessing that the back as my soundboard would give me a sharper sounding guitar than using the front would. I am also guessing that having more of a structural "box" (i.e., the bulk of the box "sides") attached to the soundboard would be more resonant than having a soundboard that is practically separate from the rest of the guitar. Is this correct? I would love to hear any thoughts or suggestions.
Many thanks... :)
P.S. I will be doing custom artwork on this one, so aesthetically it doesn't matter which side of the box becomes the "front" of the guitar.
I hope I am not going off topic too much (maybe straying towards the fringes a little). If I was making that decision I think there are some other things I would consider. If you plan to sell the instrument then it may be important to use the front of the box as the front of the guitar purely for visual reasons. This may be a big factor with some people in the choice to buy. The other aspect is how the guitar will be used. If it will be played amplified (even with piezo pickups) it probably isn't that important. If the acoustic sound matters a lot then reversing the box might be better.
I know this doesn't quite address what you asked, but I hope it helps a little.
All the best.
Yes, I really was hoping there would be no math, but you have definitely given me enough information to get my saw moving. :-) Thank you for pointing me in the direction of the more in-depth discussions too. I will definitely be looking into these things. I haven't the foggiest what Helmholtz equation is, but it certainly sounds intriguing!
Good to hear from you! :-) I generally just build these things for myself, but I do have a number of people interested in buying one. Either way, I like to build them to the best of my knowledge and ability and your suggestions are always helpful. :-)
Regarding visual aesthetics, the one I am currently working on (as well as several others) will have custom artwork, so I am sanding the boxes anyways so graphics and stuff aren't really an issue. I also have some boxes with very attractive graphics that I intend to keep. With those I'll just bite the bullet, use the front of the box and do my best to incorporate things like bridges, pickups, controls, etc. into the design as well as possible.
As for acoustic vs. electric I guess I'm one of those "want my cake and eat it too" kind of people. I build my instruments primarily to be played amplified (I like magnetic p'ups - not a big fan of piezos), but I like them to sound good unplugged too. And I know this is probably terribly subjective, but to my ear, CBGs that sound good acoustically sound better plugged in too.
It's funny. I was thinking a similar thing about the tone unplugged seeming to have an influence of the tone even through a mag pickup. I haven't made enough to be sure but I certainly get that impression so far. The only thing is there may be a difference between "nice" and "loud". As an example my last one sounds quite nice acoustically, but is very quiet (because some muppet miscalculated the neck length and the bridge had to go nearer the edge of the box than intended). Plugged in I also think it sounds nice, and in a similar sort of way. I used it in my most recent video and the reaction to it was quite good. In fact that is a piezo only one, but I get the feeling that maybe the same applies with wound pickups.
Looking forward to seeing how the work goes. All the best.
I think I know what you mean about the difference between "nice" and "loud". My most resonant CBG is, naturally, also the loudest. The same is true with it played electrically, although it can easily start sounding kinda harsh, especially if there's any appreciable amount of gain added to the signal path. I dunno, maybe it's my choice of pickups. I'll have to experiment more to see. I presently use a MXR compressor when I need to hone any overly-jagged edges down.
I'll be posting some pics, and hopefully some videos, as things progress.
And with that i am off to go watch John's newest video!!!... :-D
I usually glue the neck through to the lid of the box making the soundboard more rigid, and a rigid base for the bridge, the whole box becomes a resonator with appropriately spaced sound holes of course, different boxes have different sounds but rigidity works for me, seems to produce a less woody but more natural sound, horses for courses really. (-:
I'd use whichever side of the box is thinner (as long as it's not so thin you think it might buckle under the load from the strings). I've found that seems to give better sound results. For this reason I'm tending to use the base rather than the lid these days.
If you're worried about the aesthetics then don't be - a plain sound board looks fine and it can be nice to have some decor on the back of the guitar. Check out my Cohiba...
Also, I definitely support the view that it's best to leave the soundboard free - ie. have a gap between it and the neck.
I've recently become a pretty big fan of using the unadorned bottom side for the dulciner style necks(ie bolted and braced on top of the box, bridge contained on neck) but I have some difficulty with the 'neck-through' styles due to the added precision needed on the cuts.. I tend to use the 'neck-through' style when using the top of the boxes, if only to simplify my cuts and neck placement...
For the really cheap (masonite) boxes though, you have the easy option of cutting a new 'lid' out of your preferred thickness and choice of wood, and get the best of both worlds! I have to admit though, that being able to service an instrument without unstringing it is very convenient...in the end just keep makimg what you want until you decide on a personal preference, Lord knows I haven't found mine yet!
I haven't thought to much about the front or back ,,, but u know there is merit in that ... Problematic for me would b how to cut the openings for the neck to go thru .. I agrre with the aboves ,, if it sounds good unplugged ,, it will sound good plugged .. I got one the really good looking brickhouse boxes ,, and it ,, at this point,, is a real dissappointment . Thought it would have a really good sound ,,, unplugged it is super quiet ,, and had a bar piezo and it didn t work worth a crap .... I may really look into that useing the "back" for the "front" Tks for bringing this up
here's my two cents (and probably worth less than that!)
i always use the bottem, doesn't matter if i'm using a tin body or a cigar box. my theory involves no math, just simply this is the more ridged and solid part. the more solid something is, the better is allows vibration to travel through it. flawed as this theory may be, it's workin for me so far! good luck!