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I have it in mind to attempt to build a 'warmer' 12-string. Yes, I know I've just about offered up an oxymoron. But I have a cedar top that I could contribute to the cause.

Observations, suggestions, insights?

Thanks!

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Peter Havriluk

I have built two twelve strings along with the old Martin 12 that I didn't care for. I have also built both cedar and spruce topped guitars (not 12 strings tho). Define your terms "warmer" - how do you plan to string it and tune it? Have you thought about scale length?

The Seagull S12 is cedar topped, I think it is a nice sounding 12 and a pretty good bang for the buck guitar, but its not necessarily a sound I would want (I do tune down so I'm very biased).

One more thought - stringing "bass-ackwards" (Rickenbacker style) changes the attack on the course - you hit the primary first on the down stroke which tends to add more of the low fundamental and partial. You might want to experiment on a standard 12 with Rick tuning to see how that works with your playing style.

Reason I raised the topic is that I recently (December last year) finished a 12-string that I designed to fit into a 'classical' case: 24-inch scale length, shrunken dreadnaught body 93% of a Martin herringbone drawing. Sounds wonderful and I don't feel like I'm hugging a refrigerator. And it, by dumb luck, does not sound like a piano being tossed out a window.

So I have notions of seeing if a dimensional twin could soften some of that 12-string jangle but retain all the good stuff. My SWAG was to cedar-top a walnut body. Own the cedar, own the walnut.

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Peter Havriluk

I'll be watching, Peter. I'm going the opposite direction, smaller bodies with long scales, phat strings, tuned in the cellar. More fundament, less jangle.

I think the cedar top will warm it up some - certainly did on my OM.

Is there such a thing as a 12 string nylon? My archtop with Ambra 900's sounds very warm. I do have a plan for a 12 string vihuela in G with gut strings. So I guess they had them in the 1500's!

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Why be normal?

Tune the top to a lower frequency and use silk and steel strings.

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It will probably be alright.

I had the same hankering for a mellower 12 string, so I built a 9 string and put the octave strings on the bottom of the D,G,B strings. Half the jangle, clear bass. Easy fingering on the high E.

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Brad Hall
Mystic Dawg Guitars

In my world, the repair world and as a former builder as well the brand of guitars known as Cordoba has a joke about it that we Luthiers tell and it goes like this: What does Cordoba stand for in Spanish? Answer - bridge reglue.....

Now for the details Cordobas often have cedar tops and we see them frequently in need of bridge reglues, perhaps more than any other maker. Putting the constant tension of a 12 on a cedar top is not recommended and the entire idea of a warmer 12 is a trip to a repair luthier's shop waiting to happen.

When bridges lift from cedar tops they often take a lot of material with them making for a much more expensive repair at times.

Structural stability is key, always but what that requires on a 12 is not going to be a responsive, light touch, loud guitar make. If you want a warmer 12 build it to last and put a pick-up in and turn up the amp.

I built a 12 fret 000 12 string for my sister ten years ago with a cedar top and Honduran mahogany back and sides. Sounds great and bridge is still solid. Touch wood.

I did something similar to what Brad Hall suggested and built an 8 string (octave string courses on the 4th and 3rd strings). I find it to be a good strategy to get a fuller sound but without the full-on jangle. It also mitigates the problems of the string tension and the neck width, and makes it more playable. If you own a 12 string already why not try it out by removing a few strings and see what you think of a 8 or 9 string configuration. I think you might be pleasantly surprised. There are not many commercial builds like this, but the Martin Roger McGuinn 7-string signature model (doubled G string only) and the Taylor 8-string baritone are past examples. When you have the ability to build your own instruments you can make something individual and unique like this. It is nice to build something that you can’t buy and to get out of the mold.

I have also built several 8 string guitars with the D and G courses with octave doubles. If you use mandolin tuners you can keep the same peghead dimensions as for a regular 6 string guitar.

Much of the jangle from 12-strings comes from intonation issues. The octave strings usually require far less compensation than the regular ones, and don't usually get it, so the strings within a course tend to play more and more out of tune with each other as you go up the neck. I built a spruce/walnut 12 a while back that had full nut and saddle compensation for each individual string; it had no 'crunch' to speak of, and a very sweet sound. Every note on every string was within 3 cents or less of the 'correct' pitch. You'll need to move the nut forward toward the 1st fret by at least 2 mm, and a saddle that's at least 3/16" wide.

I've been using a very wide bridge to reduce the stress along the back edge on cedar tops, so that they'll stay down. So far, so good. I usually make them from walnut to keep down the weight. Just make sure the saddle is set back 5mm or so from the front edge of the bridge on the high E side, instead of the usual 3mm, to help avoid split outs.

Another thing that helps to avoid split outs is angling the saddle back, as seen from the end view, so that line of the saddle more or less bisects the break angle. In theory this eliminates the tipping force on the saddle that stresses the front of the slot. It's how violins get by with those tall,skinny bridges.

The intonation conflict Mr. Carruth mentioned above - - - does the problem lessen with a shorter scale length? The 12-string that pleased me had a 24-inch scale length (Martin long scale less the first fret).

Thanks!

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Peter Havriluk

Shorter scales tend to be strung with fatter (stiffer) strings to tune to the "standard" pitch and usually require more compensation. Bass strings are "loaded" with a winding to add mass and partially off set the stiffness.

There are several factors that determine the necessary compensation for a given string or set. I have not looked at scale length as a variable in 12-strings. Short scales seem to need more compensation; they 'bend' more when the string is fretted or otherwise displaced, as any electric player will tell you, and the intonation also varies more depending on how hard you fret, and where you fret. The same holds for lowered tuning, which is often done on 12s. I suspect there is more difference within a single course with a shorter scale, but, again, I don't have specific data on that.

Michael dunn of van. BC. built us a jumbo carlson 12 string in 1973. It has a cedar top, and a BRW bridge. Pretty sure he used white elmers glue. Over time , there has been a slight belly bulge behind the bridge. I/ve always tuned it down to a lower D with octave strings on the bottom 4 and doubles for the top 2 strings. Oh yea the back an sides are also BRW. Small hairline back cracks after 20 plus years