I'm working on an experimental bass resonator. What do you think?

[markmeeus]

Hi fellow bassists,

I've been working on a crazy experiment for a while now, and I just finished my 4th prototype and I think I'm getting some successes.
The idea is to build an acoustic resonator which can take the place of a cabinet in our typical setup. The fundamental difference is that the amplified electrical signal isn't used to drive a cone, but to create vibrations into an actual soundbox.
You could compare it to an acoustic bass, where the bridge (which transfers the strings energy into the body) is replaced with a pickup => cable => amp => cable => resonator chain.

My first few prototypes where either too thick or too too flexible, but now I'm getting to a point where the sound is not too bad I think.

I don't have a home recording studio, and I'm on an apartment, but I made a quick recording with my iPhone and uploaded it here:
The recording is pretty bad, and I even think the fridge was running, but you should be able to hear the acoustic quality of the Vudu Bass (that's what I call it ), which you can see in the background.

Again, let me know what you think, should I build a fifth one?

greetz,
Mark

 

[bholder]

So it's basically replacing the speaker with a resonator shaped like an URB body?

What a truly bizarre idea! Here's to Weird Science! Yeah, bad recording, but the sound comes through in spots and sounds pretty cool.
Carry on!!

 

[el murdoque]

This Idea is so genius and whacky at the same time, I would love to see it developed into a working thing.

Just a layman's suggestion from the outside, but do you have access to a knowledgeable maker of double basses?
I would wager that the form of the double bass has some tonal limitations that come from the problem that a bass maker has to account for a human that bows the strings with one hand while holding on to the neck with the other. Mayhaps there are some changes to that body that make it both easier to build and handle, while at the same time get you more volume/tonal quality/bass ?

Using the power of electrons to sense the vibrations in one (very bad) acoustic body, and then transferring those to a much better acoustic body to create the sound is such a terrible idea. I'm really into it!

 

[gtirard]

Hi fellow bassists,

I've been working on a crazy experiment for a while now, and I just finished my 4th prototype and I think I'm getting some successes.
The idea is to build an acoustic resonator which can take the place of a cabinet in our typical setup. The fundamental difference is that the amplified electrical signal isn't used to drive a cone, but to create vibrations into an actual soundbox.
You could compare it to an acoustic bass, where the bridge (which transfers the strings energy into the body) is replaced with a pickup => cable => amp => cable => resonator chain.

My first few prototypes where either too thick or too too flexible, but now I'm getting to a point where the sound is not too bad I think.

I don't have a home recording studio, and I'm on an apartment, but I made a quick recording with my iPhone and uploaded it here:
The recording is pretty bad, and I even think the fridge was running, but you should be able to hear the acoustic quality of the Vudu Bass (that's what I call it ), which you can see in the background.

Again, let me know what you think, should I build a fifth one?

greetz,
Mark

Weird and interesting. There must be something between the instrument cable and the cello-shaped resonant object, I guess some kind of magnetic element which vibrates to make the Vudu resonate?

It would be worth to make a good recording, because the sound seems "natural", but it's hard to tell because of the background noise and poor mic quality of the phone.

How loud is this? Loud enough to play with a singer? A singer + acoustic (unplugged) guitar?

 

[markmeeus]

This Idea is so genius and whacky at the same time, I would love to see it developed into a working thing.

Just a layman's suggestion from the outside, but do you have access to a knowledgeable maker of double basses?
I would wager that the form of the double bass has some tonal limitations that come from the problem that a bass maker has to account for a human that bows the strings with one hand while holding on to the neck with the other. Mayhaps there are some changes to that body that make it both easier to build and handle, while at the same time get you more volume/tonal quality/bass ?

Using the power of electrons to sense the vibrations in one (very bad) acoustic body, and then transferring those to a much better acoustic body to create the sound is such a terrible idea. I'm really into it!

Thanks for the feedback!

I'm learning all of this on the go

The thing with traditional bass building is that builders need to find an optimal balance between strength and resonance. If they build too thin, the instrument collapes under string tension, but I don't have the strength problem, because there is literally zero string tension. This means I can build as thin as possible (as long as the plates stay resonant). For now it seems that the thinner I build, the sound still gets better. I wonder where it ends

You are right about the shape I think, but I'm not sure it's just for bowing access. Having 2 bouts also creates 2 zones with different lower resonant modes. But to be honest, I just drew a shape on a piece of paper to get started

 

[markmeeus]

Weird and interesting. There must be something between the instrument cable and the cello-shaped resonant object, I guess some kind of magnetic element which vibrates to make the Vudu resonate?

It would be worth to make a good recording, because the sound seems "natural", but it's hard to tell because of the background noise and poor mic quality of the phone.

How loud is this? Loud enough to play with a singer? A singer + acoustic (unplugged) guitar?

Yes indeed, there is a coil/magnet attached to the bass bars. (They should end up on the inside at some point, this is easier prototyping). The amp sends it's signal to the coil which in turn makes the magnet vibrate at it's mount point.
I will probably take it into a studio at some point and do some re-amping with it .

It is definitely as loud as a double bass atm, but I haven't stretched it to it's limits yet. It currently allows for 40w, but I'm going to testing it with a 160 watt driver ... I'm sure at some point it will start dancing by itself, and will loose it's sound qualities even sooner.
However it will be able to stand on it's own with a Singer and an acoustic guitar for sure. the projection is really big.

 

[markmeeus]

So it's basically replacing the speaker with a resonator shaped like an URB body?

What a truly bizarre idea! Here's to Weird Science! Yeah, bad recording, but the sound comes through in spots and sounds pretty cool.
Carry on!!

Thanks! I will

 

[Michedelic]

Hi fellow bassists,

I've been working on a crazy experiment for a while now, and I just finished my 4th prototype and I think I'm getting some successes.
The idea is to build an acoustic resonator which can take the place of a cabinet in our typical setup. The fundamental difference is that the amplified electrical signal isn't used to drive a cone, but to create vibrations into an actual soundbox.
You could compare it to an acoustic bass, where the bridge (which transfers the strings energy into the body) is replaced with a pickup => cable => amp => cable => resonator chain.

My first few prototypes where either too thick or too too flexible, but now I'm getting to a point where the sound is not too bad I think.

I don't have a home recording studio, and I'm on an apartment, but I made a quick recording with my iPhone and uploaded it here:
The recording is pretty bad, and I even think the fridge was running, but you should be able to hear the acoustic quality of the Vudu Bass (that's what I call it ), which you can see in the background.

Again, let me know what you think, should I build a fifth one?

greetz,
Mark

Maybe I’m not grasping the concept, but what keeps it from feeding back?

Have you checked out the Bace? Granted, it uses a tradition pickup system…

The Bace – It's short for Bass-Cello

the-bace.com

 

[markmeeus]

Maybe I’m not grasping the concept, but what keeps it from feeding back?

Have you checked out the Bace? Granted, it uses a tradition pickup system…

The Bace – It's short for Bass-Cello

the-bace.com

There are 2 types of possible feedback here, I'm pretty sure that if you mic it on stage with monitors, the body/mic/monitor will cause feedback. This is not unlike micing a double bass or acoustic guitar.
One thing that can help is to put the Vudo off-stage, and mic it there.

When it's just the bass guitar, amp and the Vudu bass, it wil not feedback any more than a regular cabinet. You would need to have the strings of the bass to start resonating with the sound waves of the Vudu in order to get feedback.

Yeah, I've seen the Bace, interesting project too!

 

[dmt]

Very interesting idea there in separating the vibrating body from the pickup and using a wooden, cello-esque body as the speaker, mark. Good luck with figuring it all out and anything you wish to do with it at that point

 

[mambo4]

That's a new take on "how do I get my electric to sound like an upright?"
I also think that you might be able to get more speaker efficiency because you aren't necessarily tied to the shape and size of a Double bass.
What if you attached the resonator to something like a Cajon?

 

[Kacey Y]

That's a really interesting and creative idea. It definitely sounds like an acoustic bass or some kind of tenor upright or something, and not just an electric played unplugged or very clean. I just love any kind of follow through on wacky weird ideas that you don't see everyday, so very cool!

 

[DanAdams]

I nominate you for the 2025 Talkbass Hero of Innovation medal.

reamp it! I want to hear it with vocals drums and synth.

It's concept is close in form to an old plate reverb. It could be easily used on an auxiliary out to send any or all elements of a mix to.

 

[Pdaddy1978]

The dictionary definition of "thinking outside of the box ".
Literally!!

 

[Pings Bass]

That's a new take on "how do I get my electric to sound like an upright?

The best answer yet.

This is really cool concept.

 

[Raf Seibert]

Just my eye, but the first thing that struck me was that tone bars on the outside of your box looked overly sturdy. The second was that the lower notes (E string) seemed quite quiet compared to the notes on higher strings.

 

[ahbradot]

I like what you have accomplished.

 

[wjcstp]

This is a cool idea, keep going with the prototypes!

 

[monsterthompson]

Interested and following. I have no use for this (currently) but I’m hoping to learn a few things while I’m here.

 

[Wasnex]

The thing with traditional bass building is that builders need to find an optimal balance between strength and resonance.

My apologies if you already understand the following:

IMHO the limiting factor is mechanical excursion. This will limit how loud the resonator can play before incurring damage.

Your design appears to have something similar to a bass bar...but it's on the outside.

AFAIK, the mass of the front and back panel along with the mass of the bass bar has an impact on resonances. AFAIK the front and back panel can be tuned to a certain interval to produce both sum and difference frequencies that reinforce the intended acoustic range of the instrument.

A bass is built with a bass bar and sound post on the inside. The sound post couples the front to the back and also provides strength to the front so the string tension does not cause the top plate to cave in. The tension from the strings is what firmly holds the sound post in place. Perhaps rigging up something so your transducer is under tension would be useful. An adjustment could be provide so the tension is adjustable as basses tend to swell and shrink in response to season changes, especially in relative humidity. The level of tension will also have an impact on resonance of the chamber. The mass of the transducer and support structure will also have an impact on resonance. It might be better to use a cable with sort of a tale piece on the lower side and have a pivot at the top as well.

Acoustic chamber with double bass structure in brown. Transducer in blue. Bridge in green. Support structure in red. Sorry for the crappy drawing--The support structure should not come in contact with the top plate.