Speaker science - Somebody teach me

MonkeyGym

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Errrr....no.....12" speakers have 44% more area than 10" speakers.
And 40 watts is 40 watts. Whether it's pushing 12s or 10s, it's still the same amount of energy, and the net effective potential volume.
More speakers spread the sound out, or distribute the energy more evenly, which is why a 100 watt full stack with two 4x12" cabinets tends to sound louder in more places than a 100 watt single 12" combo, which will have a much smaller (1/8th) starting point for the sound. Being directly in front of the single 12" will feel like it's much louder than in front of a full stack because it is 8 times the energy per speaker. But if you are listening off-axis to the single 12, it will likely get lost pretty quickly.

Mic-ing the amps and running them through the mains is the real answer for a balanced mix.
Speaker efficiency and frequency response, and EQ, of course having lots to do with perceived volume. I should have prefaced my reply with "all other things being equal"
 

Captdan61

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I remember playing a outdoor show where the other guitar player was using a marshal head(not sure what model older before jcm800’s) and a 4x12 cabinet. And I was using a tweed deluxe and I was was told I was to loud? I could not believe my 18 watt 1x12 had that much cut. But I’m a low to moderate gain guy and I was using a les Paul with P -90’s.
 

Tangle001

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I was at a friend's gig last night...multiple guitar players...Hendrix tribute.

Two buddies on opposite sides of the stage...both playing strats with similar pedals and amps.

Stage left: 61 strat, fender vibrolux, small pedal board. Stage volume was loud but ok. Volume and tone in the crowd was huge. Full, loud, hifi. He moved a ton of air.

Stage right: Newer strat, Dr Z (40w?), small pedal board. Stage volume was outrageous. LOUD, but full and killer tone. Crowd volume was nothing. Very thin and barely heard in the mix. I kept saying he needed to turn up, but he was dimed...and killing the guys on stage.

Speaker difference? Someone explain this speaker/amp enigma to me please.
You guys are the experts but this reminds me of something I think I've found in cameras. Where if you have a group of various cameras with the same sensor size, such as 35mm or whatever, paired with lenses of the same focal length and aperture specs you may find one of the cameras giving superior picture quality in terms of overall look, I think just because there is something about the camera body that makes it all work together.
So if I am right there is a good chance that if you duplicate the rig on the left, the cabinet, circuit and circuit parts, and speakers, there's a chance you would get that same good result.
 

Wharfcreek

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There's a phenomenon called 'phase cancellation' which is an easy thing to experience and experiment around with in your own home. If you take any two-speaker cabinet and 'mis-wire' it so you have one speaker wired 'properly' and the other wired 'backwards' (out of phase) you'll immediately hear a difference in tone. The now incorrectly wired cabinet will sound thin, and bass will all but disappear. This is simply because the two sound waves coming off each speaker will effectively cancel each other out, and the lower the frequency the greater the affect.

While this is easy to demonstrate with a single speaker box with two speakers in it, it gets a bit more tricky when you start dealing with this as it relates to a single speaker source in a larger open environment. Room dynamics become VERY critical, and about every aspect of the venue has an affect on this phase cancellation thing. The point of origin, the ambient room reflection, back-wave response, sonic-adsorption, and the reflected waves from the original AND other sources become a factor. In all likelihood this problem occurred simply because the room dynamics, combined with the location of the sound source, the direction of it's projection, and the reflective aspect of that one particular set-up just fell into a place where the phase cancellation was perhaps at it's worst. Had the guy simply moved his amp over by where his buddy's was and used a longer cord he might have resolved the issue from an audience perspective as well as perhaps even sounded better in the stage mix. Sadly, this often gets overlooked until it's too late.

I might add that the surface area of two 10" speakers is considerably more than that of a single 12" speaker. So, from a 'projection and dissipation' perspective, that too could have something to do with it. Even the dispersion angle of two 10s is going to have an advantage since they create an in-phase cross-wave that adds to projection. This can help sound waves cut through a crowd. This whole concept of 'phased array' speakers is becoming quite prominent in the HiFi community of late, with a number of builders switching to using multiple drivers in their systems vs big, single-driver units. But, to conclude here, suffice it to say that in most all of the high-dollar, big-time stage venues, there's a LOT of analysis that goes into the space itself, the placement of instruments, amplifiers, speakers, and anti-reflective shielding just to avoid the phase cancellation that can take place. More than likely this was just a spot (no pun intended) of bad luck that night where your friend's amp just got set in bad location. Had the two guys switched positions, it might have been the other guy with the problem, though the two 10s might have had a better chance in that location than the one 12. Ya never know until you try, but if they're doing multiple gigs, that's what having a sound-guy is supposed to resolve on night-two!!.....lol

Hope this adds food for thought.............

Tom D.
 

David Menke

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I was at a friend's gig last night...multiple guitar players...Hendrix tribute.

Two buddies on opposite sides of the stage...both playing strats with similar pedals and amps.

Stage left: 61 strat, fender vibrolux, small pedal board. Stage volume was loud but ok. Volume and tone in the crowd was huge. Full, loud, hifi. He moved a ton of air.

Stage right: Newer strat, Dr Z (40w?), small pedal board. Stage volume was outrageous. LOUD, but full and killer tone. Crowd volume was nothing. Very thin and barely heard in the mix. I kept saying he needed to turn up, but he was dimed...and killing the guys on stage.

Speaker difference? Someone explain this speaker/amp enigma to me please.
Years ago, i was the Lead Guitar and the other guitar player had a smaller amp. I had changed often between a Hiwatt 50 and a Mesa mk3, sometimes a fender bandmaster reverb.
The other guitar player was always too loud (Fender Strat). People in the audience would tell me to turn up.
Guitars, I used a Kramer Baretta and a 87 American Strat. Problem is some players want to play as loud as they can. I always tried to balance with the Bass Player and the Drummer.
Dynamics is the name of the game in music, some do not know how to use the volume control. By the way, those volumes cause hearing loss. (Please repeat what you just said, a bit louder!! )
 

Swirling Snow

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Errrr....no.....12" speakers have 44% more area than 10" speakers.
Well, it's an old rule of thumb, and surrounds are thinner than they used to be. Nevertheless, you're obviously neglecting the fact the the outer perimeter of a guitar speaker cone doesn't move at all. Under 'T/S Parameters', what you're looking for is called 'Sd'.

Still, the point stands - more area means more efficiency through better coupling.
And 40 watts is 40 watts. Whether it's pushing 12s or 10s, it's still the same amount of energy, and the net effective potential volume.
Utter and complete balderdash. "40 watts" is a marketing phrase, required by law, that tests one dimension of an amplifier's performance. But even assuming equal power, the loudspeaker's job is to take that power and turn it into heat. As a rule, the better the loudspeaker, the greater the percentage of heat that will be dissipated as sound in the room, but, you have noticed different loudspeaker have different efficiencies, no?

Again, we're looking for why a 2x10 cabinet filled the room better than a 2x12.
 

Frank Entele

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Two 12s have twice the area of two 10s. They move a lot more air. The only way I can imagine the 10s being louder in the room is if the 12s are wired out of phase.
OOP makes some sense. An amp sure loses punch and cut that way. The other thought I had was a really low efficiency speaker set up in the 2x12…think like old Bozak efficiency (~85db spl). This is highly unlikely as it’s hard to find inefficient speaks anymore and certainly Dr. Z. Doesn’t furnish any.
 

soundchaser59

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Sounds like those guys should try turning everything down and putting it through the PA. I always say no matter where I play I always use rehearsal volume. That's all you need. Let the PA do the rest.
Post #2 - they are not mic'd, we don't know why but they aren't.
 

Freddy's Fender

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I was at a friend's gig last night...multiple guitar players...Hendrix tribute.

Two buddies on opposite sides of the stage...both playing strats with similar pedals and amps.

Stage left: 61 strat, fender vibrolux, small pedal board. Stage volume was loud but ok. Volume and tone in the crowd was huge. Full, loud, hifi. He moved a ton of air.

Stage right: Newer strat, Dr Z (40w?), small pedal board. Stage volume was outrageous. LOUD, but full and killer tone. Crowd volume was nothing. Very thin and barely heard in the mix. I kept saying he needed to turn up, but he was dimed...and killing the guys on stage.

Speaker difference? Someone explain this speaker/amp enigma to me please.
I have a 40w BF Custom Vibrolux and play in mid size rooms, ie: pubs, clubs and some gyms. I play a telecaster with a p90 in the neck and a 64 reissue in the bridge. I also play a Gibson LP with coil tap through the same unit. I have no issue cutting through drums and crowd with either guitar. The LP with the coil tap, just floods the rooms with fabulous mids. The tele, gives the raunch I want for country and instrumental play. The comment made about mids being more defined on the Vibrolux is fact. If I dial in for the single coil tele, that sets the volume for the outher guitars i play thought the amp. I set it a 4/5 and don't touch it the rest of the night. The LP boosts output so I dial it back on the volume pot as needed. The tele I play full tone and volume. I use 3 pedals, Boss Blues driver, Boss SD1 and a delay pedal. Got all the tone and volume I need. I've had a Deluxe Reverb but found the 22W doesn't cut it so I use it for practise and recording. Anyway, the Vibrolux has been a gift.
My 2 cents.
 

Daddy Dom

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Curious to know - were the amps both the same height, were they both on the floor or raised on cases? Was the Fender tilted back?
 

ficelles

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Btw...neither were mic'd for the PA.

Straight up shotgun room. Probably 40ft wide and 100yds deep.

In a 300ft long room full of people not many smaller combos will cut it un-mic'd but Fenders are notoriously loud clean for their wattage and cleaner sound is what cuts through. If the Dr Z guy was too loud on stage but not carrying out front that is a sure sign of an overly-overdriven, over-compressed sound. Sounds ridiculously loud up close but goes nowhere.
 

ahiddentableau

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I'm leaning towards the room or the type/position of the cab. If the amp was loud and cutting through OK on stage but didn't carry into the audience it's probably the room or some directionality thing going on. If it was just bad EQ choices you usually wouldn't hear it well on the stage either, although some EQ effects can get worse over distance. It's astonishing what room nodes and other physics-based effects can do with sound. Now you hear it, now you don't.
 

teletdf

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I am certainly no expert, but I think there are two main things:1) how does the rig sound to the player? I’ve found my playing is much better if I like what I’m hearing; 2) how does the rig sound to the audience? And in context with the rest of the band? That pretty much requires a competent sound tech who can “hear” the room and eq accordingly. I think Dave Rat covers this in his YT videos, as I’m sure others do.
 

robinrockus

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Ya gotta run instruments through the PA in a larger venue. Guitar amps have only limited projection. Even in the small venue we usually play I run direct to my Tech21 unit, which drives one side of my small system. It's just "there", not loud enough to cover vocals. Bass is the only instrument I don't run through PA, unless it's an outdoor gig. It's about the overall sound. Plan and play to the room. Additionally, you always want two guitars to be different. Different amps, guitars, and arranged parts for each. Chord drone/mid mud is a no-no because it drowns out everything. Think about Aerosmith, or The Beatles or The Stones. Each guitarist always had different guitars and parts. One plays chords, one plays single notes. One plays a LP the other plays a Strat, or one Tele and one hollow-body. Sometimes they play in unison, but only in certain parts of a song. Tonal variations are vital to keeping even loud volumes clean. And there is no musical point to two guitars playing the same thing all the time.
 
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Stratman2252

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Could the volume difference be the pedals they were using? I have some pedals like the Boss Blue Compressor that can double the volume. Same with my Vintage Sam Ash Fuzzz Boxx and My Zen Drive. When The Over Drives and Fuzz bo or Blade pick upses are Stacked it gets crazy loud. Amp Volume Control means nothing with pedals cranked. Its louder than straight in on 10 with any amp I own. Fenders, mesa Boogies, Ampegs, Marshall Combo, Hughes & Kettner. Other than that... Pick ups cn make a huge difference. A strat with Vintage Pick ups, or Dimarzio super distortion or "blade pick ups" will sound WAY WAY louder than Fender Noiseless pickups which I prefer. Humbuckers, vs P90's can be way different too. getting rid of the Humm will reduce the volume seriously.
 




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