Greetings all,
I'm working on another build with dual springs along the thru body neck inside the box for reverb effect. My last build didn't seem to generate that much effect from the springs, so I thought I would turn to the collective think tank for some thoughts.
What size spring works best?
What tension? (tight or loose?)
Spring material make a difference?
Thanks in advance for all the wisdom. You all are awesome!!!
Poppabear
Replies
Hi, I have not done much research or testing on the spring front but concentrated on getting a better/ fuller sound from the instrument as a whole, without the springs.
Two things I found that I will share are shown in the photos.
1- I used a cigar box or one of my custom-built boxes as a test bed for spring testing. I would fit springs as shown and at different tensions to test their response to tapping the box back or sides. I also had a CBG with a panel in the back to enable spring changes. This way I could test the response of the spring when activated by string activity and not tapping.
2- The best springs I came across, in regard to their responsiveness to tapping or string/top vibrations were the ones found on cheap desk lamps. Four springs per lamp. I came across these by accident. I have a number of these lamps throughout my workshops and was working at one bench and could hear the sounds I was making on the bench whilst working being sort of enhanced somehow. I tracked it down o the springs on the lamp attached to that bench vibrating to bench top vibrations. Now that’s responsive.
I listened to a demo of a guitar being played with and without springs, and I could hear the difference, in that demo situation anyway. I do not know where the microphone was positioned or if the spring sound was audible by the listener if a few yards away. He was playing slow single-string notes.
What I heard that guy getting I get without springs. I make the guitar as responsive as possible by the way I build it. This means that the top transfers string energy into soundwaves more easily, even in a cigar box. This also excites strings that I am not picking but are reacting sympathetically to the main notes I am picking.
One can test this. On my 3 string, I strum the high G string and I find that the low G string is also vibrating adding body or fullness to the note. Also, plucking the same string at the 7th fret will trigger the same effect. If I dampen the string I just plucked, I will still hear the note continuing from the other vibrating strings.
If I dampen the other strings and just pick one string it appears to sound dry and lacking. This effect varies over the fretboard though. And of course, is more noticeable on 6-string guitars/CBGs
Cheers Taff
That's awesome Taffy.
Taff - I was thinking of incorporating springs in a future build, and searched the forums for good suggestions. Fortunately this was one of them! In the 4 years since your post, I'm sure you've accumulated a lot more data on spring effectiveness! Thanks for the posts!
Hi, I'm learning a lot with this spring thing.
By stretching the spring to open the coils, so they stay open when the spring is no longer stretched, I think makes the spring more responsive'
My spring is easily set into motion by the gentle tapping of the back and/or sides [top not on yet].
Adding timber to the inside of the box to replicate a neck trough system killed the effect of the spring by about 50%.
I have cut out an access panel into the back so as to be able to make adjustments.
I have also started on the spring damping system
And just for even more "overkill" I'm gonna try to tune the spring to suit the resonant frequency of the box.
Taff
https://m.youtube.com/watch?v=HsuMygEUbWE
https://m.youtube.com/watch?v=qRNC5k9s09E
Hey Mikey, As I mentioned above your post, the Resobro guitar uses a blade from a putty knife under the bridge and stop tail piece to make reso sounds. Might get some ideas from that.
There was a video that Shane did awhile back of using metal yard rake tines mounted inside the box for a echo reverb effect.
Hi, my thinking is you could be inhibiting vibrations rather than increasing them, with a tin barrier installed in the box.
I suggest finding out what excites the spring into motion and improve that. That's what I have done. I'll share more later. Because we all build guitars differently, there will be different results for different guitars/builders.
Taff
Hi, I found an old spring in my scrap bits drawer so decided to experiment, I used an unfinished CBG I have on the bench. The spring is about 10-12mm diameter and about 200mm long.
I have it mounted in the box so that I can find out what excites it, and how much effort it takes to put the spring in motion.
Of course the spring has no musical sound when plucked or tapped free of any mounting, but as soon as it was mounted in the box it emitted a audible sound when picked or tapped. Next step.
i need to test how easy it is to excite the spring without touching it. This is possibly all overdoing it for a simple instrument, but I enjoy the challenges.
The spring is adjustable, I can vary the tension, this will allow me to test it's responsiveness to the exciting source. As when tuning the top and back of an acoustic guitar for for optimal output, I'm thinking that tuning the spring to work in conjunction with top and back vibrations and air movement will be beneficial.
So far I've found that exciting the spring whilst varying the tension does have an effect on the springs vibrating intesity and sustain. I've also designed a damping system so as to have an"on/off switch".
Taff