This would be absolutely contrary to how HiFi speakers are normally fabricated. Traditionally speaker manufacturers go to great lengths to remove any and all resonance from the drivers as well as the loudspeaker enclosure so that the combination of driver plus enclosure plus crossover (if doing a multiway design with different drivers handling different frequency ranges) creates a somewhat flat response across it's entire frequency range.
Musical instruments are the exact opposite. The materials and body of an instrument are designed so that it has very high resonance with which to amplify the sound and help shape the tone of some prime mover. Resonance produces nearly all of the sound given off by an instrument, efficiently translating mechanical energy applied to the device into audible sounds.
These are completely incompatible design philosophies, if not polar opposites, with the loudspeaker enclosure being constructed to kill resonance, and the instrument body being constructed to resonate in order to greatly amplify the sound producing element.
An acoustic guitar for instance have a perfectly round hole in the body over which the strings vibrate. Suppose the six strings were removed from the guitar and a full range driver of the perfect dimensions was dropped into the hole so that the body of the guitar was used as a sealed enclosure for the speaker. Or suppose a drum is used as a sealed enclosure for a woofer. Or a cell phone speaker compression mounted onto the mouthpiece of a horn. Preferably a worn out or damaged instrument beyond repair could be used, not an expensive beautiful new instrument or one with a lot of life in it.
Same principal as the instrument. The speaker cone provides a shockwave or other audible content and the instrument shapes or amplifies the sound. What kind of effects would be produced using a real instrument as an enclosure? I've heard of people using tin cans and other ratty stuff as enclosures, which were acoustically terrible, but also would make a pretty bad sounding drum set as well.
Just wondering if anyone has ever entertained the notion of dropping a driver into a guitar or drum or other instrument and observed the effects. I could almost envision the full range dropped inside an acoustic guitar body being subsequently used as an electric guitar amp, adding warmth to the sound through resonance, especially since the acoustic and electric guitar share the identical frequency range and common elements such as strings.
Musical instruments are the exact opposite. The materials and body of an instrument are designed so that it has very high resonance with which to amplify the sound and help shape the tone of some prime mover. Resonance produces nearly all of the sound given off by an instrument, efficiently translating mechanical energy applied to the device into audible sounds.
These are completely incompatible design philosophies, if not polar opposites, with the loudspeaker enclosure being constructed to kill resonance, and the instrument body being constructed to resonate in order to greatly amplify the sound producing element.
An acoustic guitar for instance have a perfectly round hole in the body over which the strings vibrate. Suppose the six strings were removed from the guitar and a full range driver of the perfect dimensions was dropped into the hole so that the body of the guitar was used as a sealed enclosure for the speaker. Or suppose a drum is used as a sealed enclosure for a woofer. Or a cell phone speaker compression mounted onto the mouthpiece of a horn. Preferably a worn out or damaged instrument beyond repair could be used, not an expensive beautiful new instrument or one with a lot of life in it.
Same principal as the instrument. The speaker cone provides a shockwave or other audible content and the instrument shapes or amplifies the sound. What kind of effects would be produced using a real instrument as an enclosure? I've heard of people using tin cans and other ratty stuff as enclosures, which were acoustically terrible, but also would make a pretty bad sounding drum set as well.
Just wondering if anyone has ever entertained the notion of dropping a driver into a guitar or drum or other instrument and observed the effects. I could almost envision the full range dropped inside an acoustic guitar body being subsequently used as an electric guitar amp, adding warmth to the sound through resonance, especially since the acoustic and electric guitar share the identical frequency range and common elements such as strings.
Last edited:
Bad idea.
Imagine reproducing recorded guitar (with all native guitar resonances) through a fullrange attached to a guitar body, adding all guitar resonances again... that would be a guitar-too-much. Or what about reproducing recorded flute through such speaker - you will not get a sound of flute, but a sound of a flute-guitar instrument... if such thing exists.
Imagine reproducing recorded guitar (with all native guitar resonances) through a fullrange attached to a guitar body, adding all guitar resonances again... that would be a guitar-too-much. Or what about reproducing recorded flute through such speaker - you will not get a sound of flute, but a sound of a flute-guitar instrument... if such thing exists.
An externally hosted image should be here but it was not working when we last tested it.
this one's been done as well...
the only two i can say anything about are the "drum speaker" and "i phone horn".
the "drum speaker" i heard sounded good.
and "i phone horns" are just passive means to make the phone speaker louder so much of what you get depends on how the horn is implemented and initial speaker quality.
i've heard a few sound quite good which is why i'm cutting up foamcore to see what i can come up with.
the "drum speaker" i heard sounded good.
and "i phone horns" are just passive means to make the phone speaker louder so much of what you get depends on how the horn is implemented and initial speaker quality.
i've heard a few sound quite good which is why i'm cutting up foamcore to see what i can come up with.
These things always reminds me of the DIY cardboard horns to enhance 'pocket' [mono] AM transistor radio performance back in the '50s.
GM
GM
Since nobody mentioned this before I have to do it my self - there is such a thing in the audio world as a "resonating cabinet" - I can only point you to the source I found it (I don't preach it or know it) - https://www.youtube.com/watch?v=sPkeY64091k - and there are other videos that talk about the way he did the enclosures - https://www.youtube.com/watch?v=SpMTNx4gy7M and this one https://www.youtube.com/watch?v=HG918vgnMBc ... the general idea is to make a semiclosed open baffle with vibrating walls but not resonating walls (the modes are damped - that's why he uses that internal bracing that cannot be calculated - each flapping section of panel must be tamed).
The idea of making an instrument as an enclosure (or vice versa) is not bad but you must accept adaptation - the same resonators are used successfully in enclosures - ex. pipes = TL, helmholtz resonator = bass reflex etc. in other worlds you have to make an enclosure rather than just mount the driver in a cello... you have to rethink the "cello".
The idea of making an instrument as an enclosure (or vice versa) is not bad but you must accept adaptation - the same resonators are used successfully in enclosures - ex. pipes = TL, helmholtz resonator = bass reflex etc. in other worlds you have to make an enclosure rather than just mount the driver in a cello... you have to rethink the "cello".
An instrumental enclosure, is build for generate the sound through two characteristics,
the shape of box enclosure and the vibration mode generated by the interaction with the material type.
but after the sound will be recording you must to mantain the information already present in the recording.
the loudspeaker reproduction will be fidelity only when the loudspeaker mantain the informations already recording already present.
An ideal loudspeaker should be neutral and transparent,
for reach this goal you must do not adds
or modifying the information already present in the recording.
This is if you want accurate reproduction.
If accurate reproduction is not your primary goal,
You are free to do as you like.
The important thing is to understand the difference between the two concepts,
Reproduction of an already recorded sound,
Or the production of a sound created by a musical instrument.
Regard
the shape of box enclosure and the vibration mode generated by the interaction with the material type.
but after the sound will be recording you must to mantain the information already present in the recording.
the loudspeaker reproduction will be fidelity only when the loudspeaker mantain the informations already recording already present.
An ideal loudspeaker should be neutral and transparent,
for reach this goal you must do not adds
or modifying the information already present in the recording.
This is if you want accurate reproduction.
If accurate reproduction is not your primary goal,
You are free to do as you like.
The important thing is to understand the difference between the two concepts,
Reproduction of an already recorded sound,
Or the production of a sound created by a musical instrument.
Regard
GM are you perhaps thinking of the Popular Mechanics article that featured a template to make a Karlson style cardboard enclosure to amplify a portable transistor radio?
if anyone has that article or a link for it please let me know.
if anyone has that article or a link for it please let me know.
Yes, I've a copy somewhere, but Freddy has posted it on occasion, so ask him for it [or anything 'K' related].
GM
GM
Let´s see what are we talking about.
Just as an example, other string musical instruments behave in a similar way, an acoustig guitar body IS both an enclosure, with a given internal volume filled with air, walls, and a vent/hole which makes it resonant at some low frequency which can be easily calculated.
It also has a "speaker" mounted on its front, which is the whole vibrating front panel, excited by mechanically vibrating strings , which transmit such vibrations through the bridge.
The tuned cabinet resonance adds a peak at a low/mid low frequency; without calculating I would guess around 150/200 Hz, to increase "depth/warmth" .
Now if you cover/block said hole with a speaker, all you get is an untuned cabinet, with a flimsy front wall to boot, which will add unexpected resonant peaks and dips .
Will it sound good/better?
In general, doubt so, except by chance, but you might like it, only way to be certain is trying.
FWIW the examples shown above added speakers to the "cabinet" but none covered the original soundhole, I guess that means something.
Just as an example, other string musical instruments behave in a similar way, an acoustig guitar body IS both an enclosure, with a given internal volume filled with air, walls, and a vent/hole which makes it resonant at some low frequency which can be easily calculated.
It also has a "speaker" mounted on its front, which is the whole vibrating front panel, excited by mechanically vibrating strings , which transmit such vibrations through the bridge.
The tuned cabinet resonance adds a peak at a low/mid low frequency; without calculating I would guess around 150/200 Hz, to increase "depth/warmth" .
Now if you cover/block said hole with a speaker, all you get is an untuned cabinet, with a flimsy front wall to boot, which will add unexpected resonant peaks and dips .
Will it sound good/better?
In general, doubt so, except by chance, but you might like it, only way to be certain is trying.
FWIW the examples shown above added speakers to the "cabinet" but none covered the original soundhole, I guess that means something.
Last edited:
I suppose the answer is to try it and see.
Just thinking of say a guitar. The strings produce virtually no sound, but as said before vibrate the belly via the bridge. But a loudspeaker cone produces a lot of sound, and the guitar would only be vibrated by the vibration of the driver frame, and the air pressure inside the body. Difficult to guess what the end result would be.
Just thinking of say a guitar. The strings produce virtually no sound, but as said before vibrate the belly via the bridge. But a loudspeaker cone produces a lot of sound, and the guitar would only be vibrated by the vibration of the driver frame, and the air pressure inside the body. Difficult to guess what the end result would be.
Well, Onkyo D-TK10 is not a driver slammed on to a guitar body, but it is very conventional two-way vented enclosure with a thin-wall construction reminiscing a guitar body. The rest is very clever marketing.
From Stereophile:
https://www.stereophile.com/content/kiso-acoustic-hb-1
"Back in 2006, when I listened to the Onkyo D-TK10, I found that it worked well with recordings of acoustic guitar, but failed to impart the natural tones of almost everything else I typically listened to, such as drums, voices, brass, and electric instruments."
Edit: That is the cost of thin-wall enclosure without damping.
From Stereophile:
https://www.stereophile.com/content/kiso-acoustic-hb-1
"Back in 2006, when I listened to the Onkyo D-TK10, I found that it worked well with recordings of acoustic guitar, but failed to impart the natural tones of almost everything else I typically listened to, such as drums, voices, brass, and electric instruments."
Edit: That is the cost of thin-wall enclosure without damping.
Last edited:
A musical instrument has many resonances. A cheap one has these resonances scattered fairly randomly around the frequency range, ending up with several very near each other, adding up to big peaks in the frequency response. A good-sounding musical instruments has these resonances well spread out, giving every note a more equal volume and tone.
The hole makes a Helmholtz resonator with the internal air volume of the body. The position of the hole is mostly immaterial, and doesn't have to have the strings going over it (some Ovation models use several smaller soundholes away from the strings). On a guitar it's roughly tuned to the lowest G note that can be played. It has a rather low Q, thus a rather wide range of notes over which it resonates, from the lowest E to maybe the D above it. It basically increases the volume of the fundamentals of these notes. It's roughly equivalent to a bass reflex speaker cabinet, with the whole top (the soundboard) being the driver. Higher frequency sounds come directly from the soundboard.
Many people wrongly put a mic at the soundhole, thinking "the sound comes out there." No, mostly the BASS comes out there, and it ends up sounding muddy or bass-heavy. Putting a mic most anywhere else near a guitar makes for a more balanced sound.
There are many types of horns, some designs are used for musical instruments, and others are used in loudspeakers. But a horn has a limited frequency range over which it works well, which is why horns are generally part of a multi-way speaker. You can make a bass horn for the back of a full-range driver, but the mids and high will still come directly from the driver.
You would want to attach the driver voice coil directly to the acoustic guitar's bridge, as that how and where the vibrations are transmitted from the strings. This just might work to "acoustify" an undistorted electric guitar signal.
- Status
- Not open for further replies.