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Howard Klepper wrote:
"If something is good, then more of it is better. It's just logical."

Like pepper.....

Those huge ports will prety much 'kill' any air resonances, or, at least, cut them down to nealy nothing. One of the 'selling points' of ports for some makers is that they 'release pent-up energy'. Well, 'pent-up energy' is just another name for a resonance, so if you release it all, there are no resonances. These can 'waste' power, of ocourse, but they also give you most of the 'color' of the sound. On my 'corker' pulling out all the stoppers seems to increase the 'monitor' effect, but also makes the tone 'flat' and 'harsh'.I did not get a chance to play any of the mega-ported boxes I saw at Montreal. Perhaps next time I can not only do that, but bring my equipment and run some tests.    

Interesting thoughts here. I was unaware that so many guitars have done ports especially of the size I saw above. There is also a lot more theory behind it than I expected. Good read!

Al - You said "I usually decrease the size of my normal soundhole on ported guitars". By how much exactly? I bound the soundhole on my guitar and mistakingly made the sound hole about 3/10" smaller in diameter (yes, I could just eliminate the binding for a fix). I posted my concern and someone (maybe it was you) suggested a side-port to compensate.

Thanks! 

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Time is a great teacher, but unfortunately it kills all its pupils - Louis Hector Berlioz

Chansen / C hansen / C. Hansen / Christian Hansen - not a handle.

Christian

[QUOTE=Dave White] Brock,

I've played Raj Spolia's 4G guitar made by Alan Beardsell like this one:



Difficult to Aa full B comparison but I got the same "pesonal monitor effect" I do on the small upper bout ports I use on my guitars. The Beardsell has a small soundhole which probably balances with the big side soundports. The view inside the guitar while I played was fabulous and you could certainly check that the bridge pins were correctly seated [/QUOTE]

Wow, that most have been some bassy guitar!! What was the tone like?

Sam,

It wasn't bassy - it had a really nice tone with great string separation and good sustain. A nice fingerstyle guitar.

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

I have noticed that some folk are using what I consider a rather large sound port. The soundport on my latest is 7/8 " diameter .
Even at this size , it raises the pitch of the guitar a semitone . Quite significant in my opinion . I wonder how much the pitch is raised by some of the bigger soundports I've seen .???
Al Carruth advises the builder to make the soundhole smaller when using a soundport .
I haven't got my figures in front of me , but I'm pretty sure if you make the main soundhole about a 1/16 " smaller,(on a 4 " soundhole ), it allows for a 1" diameter soundport without increasing that original 4 " opening .

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CRAIG LAWRENCE of AUSTRALIA
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OK, folks here know me well enough to know when I am not serious, and I appreciate that.

Speaking seriously, I have heard a couple of people insist that they heard more bass (more than what? I dunno) coming from a guitar with a really big side port. I have a conjecture about that: they are hearing a boost in the volume of octave and possibly also the octave and a fifth, and their ear/brain system is interpreting that as a boost in fundamental (although objectively, the fundamental is actually present in every even numbered harmonic). It's like a faux bass. Al? Anyone?

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

[quote=Brock Poling]I am kind of thinking of the work John Monteleone is doing.[/quote]

    Man Brock! That guitar is freak'in gorgeous! How'd you hear about this guy? Have you heard his work personally?

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Billy Dean Thomas
Covina, CA

"Multi famam, conscientiam, pauci verentur."
(Many fear their reputation, few their conscience)

Howard:
As I say, it seems as though a large port can give more output at the pitch of the 'main air' resonance. That pitch will be higher than it would be on the same guitar with no port. The impression of 'bassiness' will thus be determined by a balance between the higher pitch and greater power of the ported box, and it's hard to say offhand how that will work itself out in any given case.

The 'faux bass' idea also certainly has some merit. I often think that the 'bassier' sound of rosewood as compared to, say, mahogany, has something to do with the greater output of high frequencies in the rosewood instrument. You ear tends to take all of the power of the harmonics of the signal, and assign that to the fundamental pitch, so the added high end can come across as 'more bass', and a 'richer' timbre. I have to say this is something of a conjecture: it's hard enough sometimes figuring out what these dratted things are actually doing, without getting into what they _sound_ like they're doing.