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Nickie
06-22-2016, 06:12 AM
Does anyone know if the side port of an ukulele decreases the volume of sound coming from the top soundhole? If so, by how much?

spookelele
06-22-2016, 08:54 AM
On my alchemist... the side port doesn't seem to decrease the sound. It's pretty loud generally speaking.

hawaii 50
06-22-2016, 09:24 AM
I think if the uke with a ssp is built correctly it is louder than one without...but single traditionl ukes with no soundhole can be just as loud

Ukulele Eddie
06-22-2016, 09:28 AM
Not an issue on any of my ukes with side sound ports.

Doc_J
06-22-2016, 09:31 AM
I think if the uke with a ssp is built correctly it is louder than one without...but single traditionl ukes with no soundhole can be just as loud

I believe Len is right. The SSP gives the sound another, more direct path towards your ears. A few years ago there was a good thread in the Luthier's Lounge about this.

http://forum.ukuleleunderground.com/showthread.php?37112-Questions-about-making-a-sound-port&highlight=Sound+volume+side

spookelele
06-22-2016, 10:31 AM
part of that though I think is perception.

The top hole makes it sound louder/more direct to the player.
But the original question was for the front hole, which would be toward the audience.

Kayak Jim
06-22-2016, 12:31 PM
....

But the original question was for the front hole, which would be toward the audience.

Correct. And I think if some of the sound pressure wave is escaping through the side port, the amount through the front port must be less. So less volume through the front (top) hole.

spookelele
06-22-2016, 12:43 PM
Correct. And I think if some of the sound pressure wave is escaping through the side port, the amount through the front port must be less. So less volume through the front (top) hole.

I can not speak for all ssp's but on the alchemist... it's loud in all directions.

An interesting thing... Rebel did a whole series of different port design combo's.
HMS just put up 5 of them. They don't sound all that different in the videos.

ksiegel
06-22-2016, 05:04 PM
My Donaldson Concert with the offset sound hole and side sound port is one of my loudest, and sweetest ukes.

I have no science to back me up, but I'd say it depends on the wood, the skill of the luthier, and the acoustics (or lack thereof) in the performance space as to whether or not there is really any measurable difference in the sound any given instrument would produce with or without a sound port.


-Kurt

Recstar24
06-22-2016, 06:13 PM
My Hoffmann a style doesn't even have a normal sound hole, only two side sound ports one on each bout, and it is as loud if not louder than my other ukes (when listening to it recorded and played back)

Mivo
06-22-2016, 06:45 PM
My Donaldson Concert with the offset sound hole and side sound port is one of my loudest, and sweetest ukes.

Would it be even louder without the side soundport, though? It's mostly expensive customs that come with a port, which are of high quality and thus well-built.

Sonic waves bounce around, so if there are two openings, I imagine what comes out of the front sound hole is less "bundled", but that is possibly different from overall volume since people who sit in front of the ukulele would still also hear what comes out of the side port (sort of like an almost-stereo effect). My completely uneducated guess is that the projection is different, but volume isn't necessarily lower.

spookelele
06-23-2016, 03:36 AM
Would it be even louder without the side soundport, though? It's mostly expensive customs that come with a port, which are of high quality and thus well-built.

Sonic waves bounce around, so if there are two openings, I imagine what comes out of the front sound hole is less "bundled", but that is possibly different from overall volume since people who sit in front of the ukulele would still also hear what comes out of the side port (sort of like an almost-stereo effect). My completely uneducated guess is that the projection is different, but volume isn't necessarily lower.

The hole I think does more than one thing. Sound doesn't just shoot out of the hole, and that's what you hear. Like.. on a speaker, the driver moves back and forth, and makes the sound. There's no hole in a speaker, and it makes sound.

So.. a hole can be used to "port" meaning affect the resonance of a body. And it's size does that. It affects the frequency response of hollow bodies. But response isn't the same as volume.

For instance.. gypsy style guitars come in 2 (probably more) flavors . One has the mouth looking hole, and the other has a very small hole. The small hole one isn't quiter, but it sounds different.

Now.. a SSP does "release" sound but I think it's reflected sound, not the primary sound. The sound board vibrates, and moves in both directions. There's sound that comes straight out of the wood and not through the hole. Then there's the sound that bounces around inside, because it's hollow so there's 2 sides. I think that's the sound you hear coming out of the SSP.

So.. in a nutshell, I don't think the hole coming toward me really changes the volume from the audience perspective. The sound coming out the top is also bouncing off of me, the ceiling, etc. It's not like that sound is lost. It's just a different direction.

As far as a result of better engineering.. I don't know. I think most mass market has traditional holes because thats what people are looking for. Custom makers have people looking for something less mainstream and are more open to experimentation, because it's 1 uke for 1 person, instead of.. a factory, that would need to make hundreds of a new design that may not be popular. That being said, there are factory ukes with small hole on top and side port. The snail brand comes to mind, and one of the ones in the namm vids that aldrine put up. I've tried the snail one.. and it wasn't loud or good.. so... just having a hole on the side and top doesn't make it work. And then there's also lots of traditional hole ukes that are amazeballs. So... yes the builder has alot to do with it, but thats construction rather than tech.

Recstar24
06-23-2016, 03:40 AM
Mivo,

Spookelele broke down the physics as well as anyone. That should be all you need to know.

PhilUSAFRet
06-23-2016, 03:44 AM
There's been posts on this before, but as I understand it, the most important thing is the total opening(s) for air to escape that matters, not whether there's a personal soundhole.

ksiegel
06-23-2016, 05:51 PM
Would it be even louder without the side soundport, though? It's mostly expensive customs that come with a port, which are of high quality and thus well-built.

Sonic waves bounce around, so if there are two openings, I imagine what comes out of the front sound hole is less "bundled", but that is possibly different from overall volume since people who sit in front of the ukulele would still also hear what comes out of the side port (sort of like an almost-stereo effect). My completely uneducated guess is that the projection is different, but volume isn't necessarily lower.

Actually, I've blocked the personal sound hole, and my audience said it sounded the same. I just couldn't hear it quite as well.



-Kurt

ukulelekarcsi
06-23-2016, 11:11 PM
In short, it depends. It depends on where you're listening, on how the top is built, on how the back is built...


The hole I think does more than one thing. Sound doesn't just shoot out of the hole, and that's what you hear. Like.. on a speaker, the driver moves back and forth, and makes the sound. There's no hole in a speaker, and it makes sound.

True, and not true. The soundhole is not just the 'hole the sound comes from'. In fact, the top itself is the main source of sound, not the soundhole. But, in order to move more freely, the top needs some kind of flexibility. If the top sits on an airtight box, it will be hard to move. If the back is entirely open, like on a banjo, it will sound better. If it has vent holes in the thick surrounding plywood box, like on a dobro guitar, it will sound. If it has slits on the edge of the top, like on a violin, it will move more freely. So a sideport can be a good idea to preserve volume (even in front of the instrument) while keeping the top relatively closed. But putting a soundhole in the top is not necessarily 'puncturing the speaker'.


And it's size does that. It affects the frequency response of hollow bodies. But response isn't the same as volume.

It does in fact affect the volume as well. You can calculate the ideal 'hole vs sounding surface' ratio. The frequency response, or natural resonance, is something different. Enlarging or closing the holes can affect that. To me, it's a bit of alchemy. Some claim violin bodies should be tune to a specific note, or even the top and the back to a different but specific note. I say that once you put tension on that box, the natural frequency (the 'tap note') will change anyway. But there is a sweet spot for ideal volume when looking for the right soundhole size, given a top size.


For instance.. gypsy style guitars come in 2 (probably more) flavors . One has the mouth looking hole, and the other has a very small hole. The small hole one isn't quiter, but it sounds different.

In fact, petite bouche or oval hole guitars sound a bit louder, and more treble-ish, but that has more to do with them being 14 frets to the body, longer scale length and having different bracing (more cross-bracing than ladder). The grande bouche or D-hole guitars are used a lot for rhythm, although some claim they can be just as loud but simply lack the upper-fret access for a lot of lead duties.