Speaker science - Somebody teach me

Dacious

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Sure it's a 40 watt and not an 18?

Speaker efficiency, open vs closed back cabinet. 2 X 10" speaker as noticed mid-focussed. Probably a Custom Vibrolux Reverb not Blackface. They're a very middy amp. If it's got the white pie knobs it's a CVR. If it's got the tophat classic Fender knobs it may be a late 80/81 'Silverface' that went back to BF cosmetics in its last two years. They are loud amps.

Pedals - if I run the distortion and overdrive models on my M13 effects as they arrive preset, they're scooped and very thin. Especially through the Blackface tone stack on my Superchamp. They produce lots of topend but little punch. Complaints from band members re stage volume but little cut of authority in the mix.

So I punch up the mids and suddenly they go from buzzy and fizzy to full and fat sounding.

When I crank them for lead with volume pedal I push level, highs and mids

My Superchamp has an Alessandro SC64 10" with an SPL of 98db. For such a little box it's way loud. I can't really use it past 5 master. That's loud enough for clean headroom over a loud drummer.
 
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Swirling Snow

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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.
 

InstantCoffeeBlue

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One thing no one talked about, is whether his pedals and amp were set up for home use and not live shows.

That was sort of what I was getting at. Lots of folks get really attached to scooped amp settings, scooped speakers, pickups, etc, because in isolation, they can sound "lush", but in a band mix those kinds of settings rarely work. In my experience nothing gets buried in a mix like a Strat mid-neck position combined with an amp that has no mids dialed in.
 

EVB123

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Did the guy with the Dr. Z have his settings overly scooped in search of the "Holy Grail Mayer Tone™️", as the Strat folks like to call it😂? Because if a big powerful amp isn't cutting on stage, overly-scooped tone settings that might've sounded good at home or at band practice (especially when combined with an already scooped guitar like a Strat) are a frequent culprit.
This could be. I didn't scan tone settings, but he's tone tweaker (shred guy) and does the scoop thing sometimes.
 

EVB123

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That was sort of what I was getting at. Lots of folks get really attached to scooped amp settings, scooped speakers, pickups, etc, because in isolation, they can sound "lush", but in a band mix those kinds of settings rarely work. In my experience nothing gets buried in a mix like a Strat mid-neck position combined with an amp that has no mids dialed in.
Eq sounds like the kicker.


Now...pedals probably didn't make a difference. They rehearsed the show on that same stage and everyone said it sounded good.

Add 250 people for the show and it completely changed the dynamic. My buddy with the Z kept cranking the volume...amp and pedal levels. Crazy stage volume, but still lost in the mix.
 

Wally

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It may be that the narrow focus of that closed back speaker cab with the Z amp simply hit the wall of human bodies and died whereas the wider dispersion of the open back amp allowed the sound waves to work with the walls of the venue. If the band ever plays that room again, imho that Dr. Z amp owner would do well to bring an open back cab as an option And/or he should try a vertical orientation of the cab. Imho, he should experiment with horizontal versus vertical orientation of that cab anyway.I know which way I would orient it because I have done the experiment Multiple times., and vertical orientation provides for a wider sonic dispersion pattern. When people first hear the difference, they are amazed. A vertical orientation with the cab set in a ‘kicked back’ angled position might be best…IF one had to use a closed 2 x speaker cab.
 

PhredE

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To get a meaningful answer to the question requires that you know a set of specifics (in the very least case) about the two amps in question:

1. How is the cabinet configured/laid out? (open, closed, etc)
2. Where are cabinets positioned relative to walls, other instruments cabinets, crowd, etc?
3. (I'm a stickler for the technical stuff about speakers..)
Speaker efficiency ratings, response curves?

Knowing something of the specific model of Vibrolux and Dr Z amps would help us pin down exactly which speakers are installed in those. In cursory searches on both those, I could not find:

a). technical specs of the speaker used in the Dr Z (it's another Emi OEM/rebranded unit).
b). nor could I see evidence of a stock configuration of the Vibrolux that used speakers having efficiency greater than about 97db (after market swaps might be completely different of course).
If that amp has the Celestion 10-30s installed (95db), even in the 2x10 configuration I can see where there is a good chance for an underwhelming result. That's a moderate amount of power going into a moderately efficient speaker(s).

As an example, 32 watts into a 95 db speaker is about as loud as 16w into a 98db speaker, which is about as loud as 8w into a 101db speaker, etc.. all other factors being roughly equal.

Google search using keywords 'speaker spl vs power' or 'speaker spl vs power chart' will uncover a lot of the underlying details.
 

Lowerleftcoast

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Stage right...by the guy with the Dr. Z that was loud on stage, but not projecting at all.

Bass was definitely loud in the mix, but not bad on stage.
Imo, there are many factors that could result in this perceived volume phenomenon.

Since the Bass amp and the DR. Z were on the same side of the stage, and since you described his tone as "full and killer tone". I suspect the EQ of the Dr. Z had frequencies sharing the same space with the Bass amp frequencies. Others have stated this in different ways... scooped, same settings at home, etc. It all amounts to the same thing. Too much bass content from the Dr. Z. Not enough highs and mids.

Now, if there was a big crowd, speaker placement could make a huge difference. In a crowd if you can't see the speakers you can't hear them.
 

schmee

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I've played a 35 watt Z amp (4 x EL84) with a closed back (vintage Fender Tremolux) type cab. It was compressed and underwhelming. Less than distinct notes in a band mix. The same amp with an open back 1 x 15 cab at another gig was awesome.
 

Fullscan

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Btw...neither were mic'd for the PA.
Loud and not mic’d for PA = genuine old school! There’s nothing like playing so loud you can lean into it and be supported by all that air that’s moving. There’s an urban legend about a Hendrix concert where after the opening song the first 3 rows got up and stood in the back (too loud). Another that Vox was gonna sponsor him: he wanted 8 Super Beatles set up un a circle with him in the middle.
 

soundchaser59

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Can’t rule out the room, either.

About 2 months ago, went to see a friend’s band at a new venue. Shotgun for sure; 2 large overhead speaker arrays above the stage. No wall or ceiling treatments anywhere.

My guitar player friend says both venue owner and sound guy swear the sound was perfect - in the sound booth at the back.

However, at table up front, near stage right and could barely hear a little bit of my friend’s guitar (he was stage right, playing through TM Twin Reverb); keyboard was stage left and we could only hear what his right hand was playing, none of the low end from keys; bass was center - we could hear him plenty and drums - too loud. Vocals ok.

Reports from rear right of venue were a totally different mix, and not good.

Either bad mix or bad room or both. Good luck telling that to the sound booth.
It's hard to teach sound people to get the heck outa that booth/bullpen and walk around and just listen. So many simply assume if it sounds great in the booth then that's how it sounds everywhere. Anybody on this forum can tell you that's not true.
 

MonkeyGym

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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.
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.
 

MonkeyGym

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It's hard to teach sound people to get the heck outa that booth/bullpen and walk around and just listen. So many simply assume if it sounds great in the booth then that's how it sounds everywhere. Anybody on this forum can tell you that's not true.
That's the beauty of the new wifi and tablet based mixers, like the Soundcraft Ui24R, where a decent soundman will walk around the audience space of a show and adjust the eq and mix from point to point real-time, and hopefully come up with a "best sound for the most people" compromise.
 




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