Volume comparison between X7,X10,X20 and X30

[Earl49]

Originally Posted by JimCA

....Why is it that several report (Kramster, Kindness, Captain Jim's soundtest report listener's, me and others) that the X7 sounds louder than the larger Emeralds?

Because it is hard to quantify psychoacoustic perceptions of subjective things like loudness and tone quality. I hear the differences too, but putting a meaningful number to them is a challenge. I certainly applaud Alistair's attempt.

Originally Posted by ac

If you have a phone and are curious how loud your guitars are ...

ac, I've looked at all those apps since I nearly always have my iPhone with me, but don't always carry my $6000 sound meter. SPLnFFT is my favorite. The short answer is that they are seriously limited by the phone's on-board microphones. They can give decently accurate results -- if you also spend about $300 for an external microphone to plug into the headset jack, and assuming your phone has a jack. Newer iPhones don't have an external jack.

Originally Posted by JimCA

....Maybe it's just that "Loudness is a complex issue"?

I said this was complicated. Byudzai showed a set of equal loudness curves, where the relative "loudness" of low, middle, and high frequencies are shown on continuous lines at various levels. Those curves were developed under controlled laboratory conditions by juries of listeners who rated the subjective loudness of each level and frequency on each curve.

There are six acoustics textbooks sitting on my desk right now, each with multiple chapters discussing sound quality, measurement, loudness, and how to quantify noise in general. So just imagine the challenge that I face trying to explain sound and noise levels to a City Council at a public hearing. You introduce a bunch of concepts (like A-weighting and averaging levels over time) to fairly assess the overall situation versus the one aspect that people are concerned about - momentary levels created by one particular sound.

One recent example: a truck terminal next to a trailer park. It seems an obviously incompatible situation on the surface. But those homes are only 500 feet from the interstate, with frontage on a road that has significant industrial truck traffic already, under the flight pattern of the airport, and about 1500 feet away from major railroad tracks. There is plenty of background noise in the area already, and overlaying the expected noise from a few dozen trucks per day showed no net increase in the area. That was NOT a popular conclusion with the residents....

[casualmusic]

Would it matter if this test is dBA or dBC?

Thanks.

.

[Earl49]

Originally Posted by casualmusic

.......Would it matter if this test is dBA or dBC?

Yes it would. A-weighting rolls off the very low frequencies to better correlate human hearing and judgment of loudness to the meter's reading. It is essentially the inverse of equal loudness contours. C-weighting is essentially uncorrected (except for the most extreme highs and lows) and better reports content with low frequencies. For example, dBC is used by many noise ordinances when dealing with amplified music and industrial noises, where dBA would definitely under-report the levels versus the actual perceived annoyance. The Wikipedia link that I provided earlier show a graphic with the relative corrections of dBA, dBC, and others.

The best way I've come up with to explain how we selectively hear higher frequencies better is : It doesn't matter much to your survival if you hear distant thunder or a roaring waterfall. It makes a huge difference hearing the twig snap nearby as the Grizzly bear sneaks up behind you!

[casualmusic]

Earl.

Thanks for the clarification. Guess it's less complicated than I thought.

[casualmusic]

Revived to help x20 vs x30 discussions.


BTW: The guitars at jam sessions I've attended play alternating bass and treble strums on backup, and play solos with melody/countermelody or chord melody. Would separate comparisons of bass strums and treble strums provide useful info?

.

[Earl49]

Since we have reactivated this thread (thanks for finding it) I have added SPLnFFT to my phone and bought an external microphone..... MicW i437L with lighting plug from Sweetwater. I can check this 1/4" mic for accuracy using my field calibrators that get lab certified each year. The SPL numbers that it gets agree pretty well with my pro-grade sound meters.

The short answer is that loudness -- like beauty -- is largely in the eye of the beholder -- much like good tone. I've never seen a meter that directly displays "loudness". No doubt there will be differing reports on the perceived loudness of various models based on the player's ears, playing style and technique, the room, the time of day (ear fatigue), and other factors.

Originally Posted by casualmusic

BTW: The guitars at jam sessions I've attended play alternating bass and treble strums on backup, and play solos with melody/countermelody or chord melody. Would separate comparisons of bass strums and treble strums provide useful info?

Yet another complicating factor. Pure tones are easier to hear ad identify than blended strums. Our brains are pretty sophisticated analyzers - way better than any meter or box that can be bought. If I were trying to document the "levels" from a guitar, I would have the player do whatever for a solid minute - boom/chuck playing in your example -- and take the *energy* average (Leq).

[dmcginnis]

Thanks for finding these videos again - I had seen them back when they were new, but could not find them. I agree that style of play is critical, too. The boom-chuck of alternating bass and treble strum patterns is not common in Irish music. For my style, I like to really stay behind the melody instruments (e.g. multiple fiddles) and support them. Thus, the backing can range from appropriate rhythms on chords to counter-melody lines. It is all about support for the melody, not competing with it.

From listening to these videos, it is apparent that the guitars all have their own sound profile in both loudness and spectrum. The X-30 has a fullness that I think would really do well in an Irish session as it has the bass to provide a solid foundation for the melody to soar above. The mid-range and trebles standout in all these models, but the X-30 has the bottom end that makes it really different.

[steelvibe]

[mikealpine]

And I didn’t hear wolf notes.

The X30 has some presence!