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  #1  
Old 03-26-2017, 07:46 PM
captwingflap captwingflap is offline
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Default Sound Port

I have a Yairi PYM 70 that I have a love/hate relationship with. I like everything about the guitar except its overall sound. I have tried dozens of string combinations, pick material etc, but it still sounds "funky" sometimes. Problem is, unanimous feedback from folks who know tell me the guitar sounds really good. Really good. In desperation, I laid the guitar on my lap and played it so the sound would project right at me. The difference was remarkable. My question is, do you think that if I had a soundport cut in the side, it would make a difference to my ear? Many thanks, Ken
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Old 03-26-2017, 09:28 PM
ricklt ricklt is offline
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I think cutting a hole in the side would alter the tone of the guitar. Personally I wouldn't cut that hole without first verifying the affect on tone. May not be much, but could be major.

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Old 03-26-2017, 09:44 PM
Halcyon/Tinker Halcyon/Tinker is offline
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I have found soundports alter the sound only very subtly in most cases. If you're hoping a soundport will magically transform a guitar you don't like into one you do, I think you'll be disappointed.
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Old 03-26-2017, 11:38 PM
runamuck runamuck is offline
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I've cut two soundports in guitars that didn't originally have them. Before cutting them both were recorded a number of times. Here's my experience with the two.

- I could not hear a difference in either guitar between the recordings pro and post soundports.

- Both sounded noticeably different playing the guitar after the soundports. In both cases, there was an increase in volume and the higher frequencies were accentuated from the player position.

- I learned that with these two guitars, at least, a soundport is not a good place to mic guitar for a recording.

- What you hear from a soundport in the player position is nothing like what a listener hears in front of a guitar.

Good luck,

Jim
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Old 03-27-2017, 02:15 AM
LSemmens LSemmens is offline
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Change you playing position. Play facing a corner and you'll hear what everyone else hears. Not much good for performing, but great if you want to know what your audience hears.
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Old 03-27-2017, 03:58 AM
murrmac123 murrmac123 is offline
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Quote:
Originally Posted by ricklt View Post
Personally I wouldn't cut that hole without first verifying the affect on tone.
Just like you should never go into the water until you are able to swim ...
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Old 03-27-2017, 04:16 AM
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srick srick is offline
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Originally Posted by LSemmens View Post
Change you playing position. Play facing a corner and you'll hear what everyone else hears. Not much good for performing, but great if you want to know what your audience hears.
Agree 100%. Also, humidity is a big factor in what you hear as are your strings.

I have a Guild GAD30 which I cut a soundport into (n=1 <G>) and it does allow me to hear the trebles in the guitar " a little" better, but I would not do it again. In exchange for hearing more treble, I hear less bass. But, it is your guitar and you'll never know until you try.

best,

Rick
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Old 03-27-2017, 06:24 AM
redir redir is offline
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FWIW the only experience I have with sound ports is one that I cut into a guitar that didn't have one originally... I noticed no difference at all.
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Old 03-27-2017, 10:42 AM
Howard Klepper Howard Klepper is offline
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Go ahead. It's easy! Here's an instructional video:

https://www.youtube.com/watch?v=EnJT-20YbV0
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Old 03-27-2017, 11:44 AM
redir redir is offline
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Well that is certainly one way of doing it. But I'd still recommend reinforcing the inside
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  #11  
Old 03-27-2017, 12:16 PM
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There are so many variables that come into play with placement, size, original body size of the guitar, what the current tonal picture is....etc, etc.

I'm guessing your guitar is probably leaning toward the bright side of the spectrum? If so, I think you may find a benefit from a propertly placed port or ports (my preference normally)

I've ported probably two dozen guitars and have found my ear really likes starting very small and putting them on both bouts like this:



This is a Cordoba C9 classical that pretty much went from an good sounding classical to one that keeps up with those many times it's price.

Start with maybe a couple of dime size holes and see what it starts sounding like. I wouldn't go too much larger than that with a Parlor sized instrument.

To get the most out of ports - you really need to sit and play somewhat in the classical position so the ports are staring right at you. If you stand and play with a guitar on a strap and up against your belly, you are already greatly reducing the tone and volume of the instrument and the ports will be of little consequence.

Here's what I've almost always found to be true regarding ports:

They tend to increase the output out front slightly - working like a breather hole on a gas can.

Almost always fattens up thin or shrill sounding trebles.

Evens out the response of the guitar across the spectrum making it easier to record (especially true with classicals)

General warming up the tone and increasing the volume coming up to the player.
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Last edited by fitness1; 03-27-2017 at 12:27 PM.
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Old 03-27-2017, 12:55 PM
Alan Carruth Alan Carruth is offline
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I've done 'WAY more experimental work with ports than I ever intended to, and I'll try to summarize the results.

Cutting a port will alter the resonant modes of the guitar that give it it's 'voice'. Which ones, and by how much depends on where the port is and how big it is.

Any port will raise the pitch of the 'main air' resonance by some amount. This generally only makes an audible difference in the tone if it starts out or ends up very close to a played pitch. Often the 'air' resonance is close to the G on the third fret of the low E string. If it matches that note, or another exactly before or after you open the port you can end up with a 'wolf': a note that's twice as loud for half as long. Usually what you hear is the lack of sustain.

Otherwise, in general, the larger the port is, and the further it is from the main sound hole, the bigger difference it will make.

Ports work best as a 'monitor'. On a normal guitar the bass notes are so low in pitch that the guitar puts them out as a 'point source': the energy goes out about equally in all directions, and the player hears them as well as the audience. As you go up in frequency the guitar becomes more 'directional', with the higher pitched stuff going out of the hole and off the top toward the audience. Unless some of that sound is reflected back the player may not hear it. A port that you can look into when you're playing will send some high frequency sound out toward you directly. Again, the closer it is to the main hole the more it will sound like the guitar does out front.

A port need not be very big. I've gotten useful results with a 1" hole, although a bit bigger could be better. I'd worry that a port bigger than 2" was altering the tone too much, but I'm a tone geek.

Blind listening tests that I, and others, have done, suggest that in a small, reverberant room a port doesn't do a lot of good. However, in a large, or dead room, or one with some background noise, it can make a clearly audible difference. I did much of my testing at two Montreal Festivals, in a 'dead' ball room with an average background of 'white' noise at 70 dB-A or so: almost everybody could hear the difference. Some folks who have a degree of hearing loss, particularly if it's age-related loss of high frequency acuity, say the port helps them even in small 'live' rooms.

The bottom line is that a port is not some magical elixir that will improve any guitar, nor is it all smoke and mirrors. In your case, it may well prove a boon. I tend to put them in the right (bass) side just below the wide part of the upper bout, and I do reinforce the side. When I'm making a new guitar with a port I'll reduce the size of the main hole a bit to keep the 'main air' resonant pitch where I want it. It's a little hard to say how much to reduce it, though: it's not a simple area-for-area swap.
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Old 03-27-2017, 01:25 PM
Earl49 Earl49 is offline
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Quote:
Originally Posted by LSemmens View Post
....Play facing a corner and you'll hear what everyone else hears. Not much good for performing, but great if you want to know what your audience hears.....
My favorite place to play to judge my instrument's tone is sitting in the focus of my kitchen's bay window, looking out over my back yard. Three large pieces of glass reflect the direct sound back at me, and the experience is completely different than even playing in a "live" or reverberant room. The near-field reflections from glass are more immediate sounding than the enveloping sound of a reverberant room.

I have experimented with impromptu sound ports by opening up the barn door on my guitars that have those -- not a lot of difference. There is a 1-7/8" diameter sound port in the upper bout of my Blackbird Lucky 13 (00 sized). I have tried covering that port with my hand while strumming open chords and don't really notice much difference. I presume that Blackbird experimented with various sound port locations and sizes as they developed this excellent little guitar. The sound port is now standard, but they will also build one without it upon request.
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Old 03-27-2017, 03:00 PM
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Quote:
Originally Posted by Earl49 View Post
There is a 1-7/8" diameter sound port in the upper bout of my Blackbird Lucky 13 (00 sized). I have tried covering that port with my hand while strumming open chords and don't really notice much difference.
Try stuffing a sock or something similar in the hole and play as you normally would, then pull it - I'd be really surprised if you said "not much difference"
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  #15  
Old 03-27-2017, 09:11 PM
mirwa mirwa is offline
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If you decide to go ahead, have a good read on installing them, google for more info, I have a walk through tutorial on installing one, it may be of benefit, it may not.

http://www.mirwa.com.au/HTS_Install_Soundport.html

Steve
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