String tension effect on resonator? 8 string resonators

[Tim Toberer]

Howdy all! I decided to post this over here because there doesn't seem to be much interest in resos over on the builder forum.

I am designing an 8 string resonator guitar with pedals (a sequel to my 8 pedal canjo guitar) using a spider cone instead of a 6" can and I am not sure on the scale length. There is an assumption that longer scale length and heavier strings equals more sustain better tone, but I am not sure if this is true. There must be a sweet spot. From my experiments with other resonators, at some point, pressure on the resonator seems to suppresses sustain and kill the tone as well. I tend to favor shorter scale lengths in general for ease of playing, but I don't want to compromise the tone too much.

Since there will be 8 strings instead of 6, there will be more pressure on the cone, so a shorter scale length should work. I designed the guitar around a 23" scale, but now I am thinking maybe 23 1/2 or even 24 might be better. Any thoughts? I searched the forum and I found at least one example of an 8 stringer with a 23" scale by a well respected builder, but most would consider this to be too short it seems. String gauges are easier to experiment with obviously. I figure I could beef up the gauges a bit if the tone is flubby. Any 8 string reso players out there??

I want to build with tricones next.

[Mike Harris]

My 8-string (McKenna) resonator guitar has a string length around 24 3/4 to 24 7/8 inches. I think my strings are standard tension. I bought it used and have had it for several years with no problems that I am aware of.

[Tom Jordan]

My 8 string Goldtone PBS is right at 24 7/8" or 25", depending on your eyeball.

Tuned in a pretty standard G6 with no issues. Great sounding guitar.

Tom

[Michael Lester]

Not sure if this adds to the discussion, but...

I have experimented with as many variations of string gauges and tuning on my 8 string reso as I could.

In my case. lighter strings gauges were tried to allow C6 high G tuning like my lap steel. Tone and string vibration almost completely disappeared. Just a series of 'thuds' especially on the lower strings.

I tried heavier custom gauged sets purported to be from Mike Auldridge for several tunings including A6 and G6 and an E variation. The heavier strings really restricted vibration and seemed to stress the cone and spider.

The best I've come up with at the moment is a 'medium' guage string set tuned to G6. Not my favorite tuning but it is what it is. Guitar sounds good, but not extraordinary.

[Tim Toberer]

I should have mentioned the tuning changes between 6th chord inversions. G6 is obtainable but it has the 6th on top GBDEGBDE low to high. A6 and C6 with E top are available as well. My other 2 guitars are a 22.5 scale and the tension and tone seems best with standard C6 pedal steel gauges.

For this guitar I am thinking phosphor bronze but probably have to go a little heavier if I stick with 23" scale. The main reason I want a short scale length is I am trying to keep the size and weight down. A shorter scale will allow for a lighter build. When setting up these guitars you are repeatedly picking them up and flipping them over on the workbench. No Birdseye Maple either for this one sadly, I am building the body out of Aspen or Pine. Thanks for the responses!

[Stephen Cowell]

All of the pedal resos I've played suffered from drop... can't call it 'cabinet drop' so I'll call it 'cone drop'. The tuning switcher tailpieces get around this by allowing a compensation *on each string* when you switch tunings. Doing this for more than one pedal is going to be crazy hard... good luck.

[Tim Toberer]

All of the pedal resos I've played suffered from drop... can't call it 'cabinet drop' so I'll call it 'cone drop'. The tuning switcher tailpieces get around this by allowing a compensation *on each string* when you switch tunings. Doing this for more than one pedal is going to be crazy hard... good luck.

Can you explain a bit more what you mean? I am pretty new to these instruments and pedal steel players always refer to cabinet drop. Not sure what this is? How many pedal resos have you played and which builders? It is pretty much Franklin and Hudson from what I have seen, both extremely rare guitars. Were they playable? I have never seen one in person, I just built mine based on what I could figure out from pictures etc.

The guitars I built are very playable. Both have 8 pedals and raise and lower each string. The tuning is equal temperament. I didn’t make any special compensation. I find the slight tuning anomalies to be completely acceptable. Now that the strings have settled in I just have to touch up the tuning every few days. I suppose the efffect you describe might be worse on a spider cone? Or maybe I am just having good luck.

[Tim Toberer]

I found this post on cabinet drop. https://steelguitarforum.com/Forum5/HTML/005189.html I can see why this may be more of a problem on an acoustic instrument where string pressure will distort the cone and effect the tuning on strings that are not raised or lowered. In the tuning I am using, there are no whole tone raise or lowers, only 1/2 tone, so this effect should be minimized hopefully.

It seems there are a few things steelers obsess about regularly. Tuning is one of them. I have read long threads on the comparisons between equal and just temperament sweetened tuning etc. I tend to just think is it in tune or not? Non pedal players seem forced to live with the sketchy tuning of slanting. This is one of the main reasons I am getting into pedals. I like having full 4 note chords in straight bar for all the major chord groups.

[Chris Templeton]

I had a Beard 7 string dobro and I definitely noticed damping of the resonator cone when adding the 7th string to it, changing strings.

[Chris Clem]

I"m not sure the Reso guys are going to love those scale lengths. That coupled with the 8 strings not really getting the sounds people had hoped for on cone guitars. Would make me pause. But that's just my thinking.

I'm all for trying something new. But as a builder and knowing how much work it will take to build this. I would want the odds for success to be a little better.

But then again...sometimes you need to give it shot!

[Chris Templeton]

When I played dobro for Dan Hicks, I used the Beard 7 string tuned to C6th and found its sound headed towards that of an amplified, acoustic guitar with the extra string damping the cone.
For the 7th string, Paul Beard just drilled another hole in the tailpiece for the ball of the string, and the angle of the seventh string from the tailpiece to the bridge, was too sharp and if I wasn't careful, the string would jump out of the bridge slot. Very embarrassing.
Here's Mike Aldridge's "Eight String Swing" record for some eight string dobro to enjoy. I don't recognize the dobro brand:
https://www.youtube.com/watch?v=B3VS0bOFxNU

[Tim Toberer]

I"m not sure the Reso guys are going to love those scale lengths. That coupled with the 8 strings not really getting the sounds people had hoped for on cone guitars. Would make me pause. But that's just my thinking.

I'm all for trying something new. But as a builder and knowing how much work it will take to build this. I would want the odds for success to be a little better.

But then again...sometimes you need to give it shot!

I have been losing a bit of sleep over it. It is a ton of work, but I am just doing it for myself and it is enjoyable. I am feeling a bit better after using a string calculator and comparing the pressure from a standard nickel string reso set on a 25" scale guitar, to an 8 string guitar with a 23" scale, I can get the pressure pretty much the same by using slightly larger gauges. Bumping the scale length up to 23.5 or even 24 is maybe not a bad idea, but using a 25" scale increases the pressure quite a bit.

Unfortunately there is only one way to find how well it works.... It would be interesting to hear a direct comparison between resos with different scale lengths.

Forum member Jim Bates has or had? a custom 8 string with a 22.5 scale that he tuned to A6 using G6 string. The old Fender 400 pedal steels had a 23" scale so it's not really unusual for steel guitars in general.

Here's Mike Aldridge's "Eight String Swing" record for some eight string dobro to enjoy. I don't recognize the dobro brand:
https://www.youtube.com/watch?v=B3VS0bOFxNU

What a great record!

I recently discovered this guy. Great player, seems to be a very good teacher as well. https://www.youtube.com/watch?v=S9x5u9KhVqU

[Noah Miller]

I never really thought about this, so I did an A/B with my Beard 7-string taking one of the strings off. There was no noticeable difference in volume, but the tone was noticeably better with that 7th string on there. It was more balanced, with less flub in the bass.

[Tim Toberer]

I was able to extend the scale to 23.5 without altering my plans that much. I am trusting that with the 8 strings and relatively higher pitch I can make it work. The pressure on the cone should be on par with a 6 string at 25" scale length, actually slightly higher. This is using standard gauges. The standard 6 string has about 217 lbs. on the cone according to this calculator. I am sure I will have to experiment a bit. Resonators in general seem to like heavy strings. I got my resonator parts yesterday (the cheap ones), the quality seems actually very good. The cover is beautiful! If it works I can always update to a nicer cone at a later date.

This guitar will never sound like a Beard, probably more Rogue if I am lucky. There is too much compromise in the acoustic design to allow for space for the pedal mechanisms. I am feeling confidant it will sound better than my 6" tin can powered guitar (which sounds better than most would expect!)

[Tim Toberer]

I have had the week off with all too much time to think about this and I think I am coming around to more of the consensus. Need longer scale. I bumped it up to 24" while there will be substantial more pressure on the cone compared to a 6 string (especially when I do a double or triple raise) I am thinking the tone may have more to do with the individual pressure on the cone from each string, and not the entire weight. It is hard to think Beard or Franklin would be wrong. I do think a slightly shorter scale is a good idea. 24" seems more reasonable.

Another change in plans. I will be using Birdseye Maple. I scored some yesterday and I have to use it!