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Topic: What would be louder? |
Paul Sutherland
From:
Placerville, California
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Posted 8 Jul 2014 2:57 pm |
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Assuming that what really counts is the volume (as in strength or hotness) of the signal that goes into the PA from a mic on a guitar cabinet:
A mic on a single 12 speaker driven by 15 watt tube amp? or,
A mic on a single 12 speaker which is part of a 4x12 cabinet, also driven by a 15 watt tube amp?
Assume both cabinets are closed back (or both open back if you prefer), and further assume the speakers are all the same brand and model, and the impedances are all correct.
I'm wondering is the single speaker in the 4x12 cabinet getting less power because the amp's output is spread out over 4 speakers, so it's lower volume (which would be good for what I'm thinking about).
I know the 4x12 would be louder on stage and in the room, but would it be lower volume at the same amp setting when mic'd into a massive PA in an outdoor setting?
_________________
It don't mean a thing if it ain't got that swing.
Last edited by Paul Sutherland on 9 Jul 2014 10:06 am; edited 1 time in total |
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Dave Grafe
From:
Hudson River Valley NY
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Posted 8 Jul 2014 9:52 pm
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Whoa there pardner, one at a time and we can untangle this knot...
First of all, how strong a microphone signal one pushes into a PA is not necessarily "what really counts" at all. Many of the best sounding microphones have lower outputs than the most popular cheaper ones. In the final analysis accuracy of reproduction trumps volume at every turn.
Secondly, not all microphones or mixer inputs perform better at higher volumes than at lower. That being said, and similarly assuming that radical impedance mis-matches do not pose a threat to an amp's integrity (which is most definitely NOT a sound assumption)...
If you connect 4 identical 8-ohm speakers, wired in parallel, to a transformer-coupled tube amp, each speaker will receive 1/4 of the total output power of the amp, but one 8-ohm speaker would receive that same power as well, the total power - and volume - available would remain basically the same regardless of the load impedance.
If you did the same with a direct-coupled solid-state amp, each of the 4 speakers would still receive 1/4 of the output power, but at 2 ohms the amp is delivering up to four times the total power as it would when facing 8 ohms, thus the four speakers are significantly louder than, and any individual speaker is approximately as loud as, any single speaker at 8 ohms would be. |
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Paul Sutherland
From:
Placerville, California
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Posted 8 Jul 2014 10:50 pm
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Dave: I'm sure there's a better way to state my question, but I'm not exactly sure how to do it.
Let me try again.
If you mic only one speaker on a 4X12 (or 4x10) cabinet, then that one speaker is only getting 1/4 of the amp's power, so even though the cabinet is louder overall (when standing anywhere close to it), wouldn't the signal going into the mic not be as hot as it would be if the total power of the amp was going to a single speaker that was mic'd?
Assume same amp head, all impedances are correct, same microphone and mic placement (close mic'd), & same mixer/board on the PA. The only change is 1x12 vs. 4x12.
_________________
It don't mean a thing if it ain't got that swing. |
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Lane Gray
From:
Topeka, KS
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Posted 8 Jul 2014 11:55 pm
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I'm with Dave. I don't understand the motivation behind the question. Given the gain available in a board/whole system, the TONE of the cab should be a lot more important than how loud the source sound.
Nearly every mic in front of an amp is gonna have its gain on the board lower than vox, so there is a lot of unused gain left on the table.
A single speaker will radiate the entire output, and one out of 4 will radiate only a quarter of the output. So assuming identical efficiency, a single speaker radiating 200W should be louder than a speaker radiating 50.
When a sound tech wants more volume to get a hitter signal, my answer is to move the amp a couple feet farther away from me. I know how much balance of me vs. the rest I believe is right, and if they want more of me (and can't figure out how to boost me in the board), I'll play louder if the amp is farther from me, since it has to be louder to hit my ears the same.
_________________
2 pedal steels, a lapStrat, and an 8-string Dobro (and 3 ukes)
More amps than guitars, and not many effects |
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Stephen Cowell
From:
Round Rock, Texas, USA
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Posted 9 Jul 2014 6:01 am
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Paul, I think you're right... the speaker gets 1/4 the power. Not sure why you want this, but it's true.
Given that you can build your 4x12 out of four 1x12 cabs, and you can wire them to be the same impedance using series/parallel wiring, then yes... the mic'ed 1x12 will be 6dB louder than the mic'ed 4x12. The 4x12 will have more bass, since the wavefront is established over a larger area... and it will be more directional, since you have a phased array effect going on... but that doesn't matter in close mic'ing for the most part.
_________________
New FB Page: Lap Steel Licks And Stuff: https://www.facebook.com/groups/195394851800329 |
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Paul Sutherland
From:
Placerville, California
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Posted 9 Jul 2014 9:32 am
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The purpose of my inquiry is, how do you balance the inputs into the PA so that the FOH mix is a reasonably balanced mix when sent to a video recording.
A band I play in recently played at a large outdoor amphitheater with a very high end and large PA. One of the benefits of the gig was we would get a video of our performance with TV quality cameras, etc. But when we got the video the lead guitar player was way too low in volume, and the bass and my steel were somewhat too low. I asked about adjusting the volumes and was told we couldn't because the audio was simply a feed from the FOH mix. The FOH soundman did a superb job in the mixing of the headliners so I have no reason to think he screwed up. Plus all our fans in the audience said we sounded great.
Obviously we would prefer being able to adjust the volumes, but this got me thinking that maybe there's a way to move closer to getting a balance mix using just the FOH mix if we can even out the inputs into the house PA. Just telling the guitar player to turn down, or use a smaller amp is not likely to be meet with much enthusiasm. Besides I agree he was not loud enough in the mix, even though he was clearly loud enough on stage and to the audience.
The guitar player used a 50 watt tube Carvin combo amp with 2 twelves. There was a mic on one speaker. If instead he used a 4x12 cabinet, and if he could be talked into using an amp head of less power, ie, 15 watts or even down to 5 watts, then the signal hitting the one microphone on the one speaker would be less so the FOH soundman could turn him up in the mix, yet he would still have the volume on stage that he needs.
Does that make sense? Is this an idea that might make a real difference? It's possible we could play this venue again, and it would be nice to get a better video out of it.
PS: The moral of the story for me is; if you want to be heard, turn down.
_________________
It don't mean a thing if it ain't got that swing.
Last edited by Paul Sutherland on 9 Jul 2014 10:10 am; edited 1 time in total |
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Lane Gray
From:
Topeka, KS
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Posted 9 Jul 2014 9:56 am
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Turning down is HARD, at least for me. My key to raising my presence in the mix is to move my amp to right by my side, aiming across the stage and up: basically no more than 3 feet from amp to ear. You'll turn down pretty good on your own. AND your amp will impact less on FOH since it doesn't aim that way.
_________________
2 pedal steels, a lapStrat, and an 8-string Dobro (and 3 ukes)
More amps than guitars, and not many effects |
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Tony Prior
From:
Charlotte NC
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Posted 9 Jul 2014 11:41 am
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why would it matter to the PA input, just tweak the trim or the gain...nothing , or probably nothing, going to the PA inputs have the exact same volume levels...even singers, line up 10 singers using the exact same mics and you will have to adjust each channel gain differently.
I understand the question but not the reasoning behind it..the PA doesn't care., that's why it has separate gain controls for each channel...
_________________
Emmons L-II , Fender Telecasters, B-Benders , Eastman Mandolin ,
Pro Tools 12 on WIN 7 !
jobless- but not homeless- now retired 9 years
CURRENT MUSIC TRACKS AT > https://tprior2241.wixsite.com/website |
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Paul Sutherland
From:
Placerville, California
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Posted 9 Jul 2014 12:28 pm
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"Presence in the mix". That's the phrase I was looking for. Of course each input into the PA will be at a different level. But to the extent that a band can adjust those levels by the equipment they use to somewhat more equal levels, and still get the tone and volumes on stage they want, that seems like a good thing.
So to increase your "presence in the mix" lower your input into the PA. The more the FOH soundman can turn you up, the better. And then maybe, just maybe, you might get a reasonable mix when recording live in the situation I described.
_________________
It don't mean a thing if it ain't got that swing. |
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Lane Gray
From:
Topeka, KS
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Posted 9 Jul 2014 1:03 pm
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Tony, Paul touched on the reason.
A good sound tech (having known good women running sound, I'm REALLY trying to kick "sound man" from my vocabulary) will listen to the sound as it hits the house. If the amp is loud, the engineer will turn you down because your amp is doing a bunch of the job of filling the house.
Not a problem, unless you listen to a board tape. Then you won't be there, since you filled the house.
My practice of putting the amp just inches from my hip was actually the tech's idea. He preferred it when the stage projected as little as possible to the house.
Side benefit: the band could TALK to each other (as opposed to yelling) during a song.
_________________
2 pedal steels, a lapStrat, and an 8-string Dobro (and 3 ukes)
More amps than guitars, and not many effects |
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Roman Sonnleitner
From:
Vienna, Austria
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Posted 9 Jul 2014 1:10 pm
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Most likely, the lead guitar etc. were too low volume in the FOH mix, because the amps on stage already contribute to the overall volume in front of the stage, so the sound tech has to turn them down in the mix, to compensate for the sound of the guitar, etc. coming from the stage/amps.
If you have to use the FOH stereo mix as source for your video, the only way around that is to turn down the amps (and turn up those instruments in the monitors), so the sound tech has to turn them up in the mix - whether you are using 1x12" or 4x12" speakers or whatever doesn't matter, it's just a question of stage volume, and in your case as low as possible would be best.
The ideal way to this, though, would be to use an extra AUX channel to do a seperate mix just for the video (of course, that requires that the sound tech is willing to do that, and the board has an extra AUX channel available...)
EDIT: Lane explained the whole thing while I was still typing...  |
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Paul Sutherland
From:
Placerville, California
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Posted 9 Jul 2014 2:01 pm
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The soundman was 200-300 feet from the stage and this was outdoors. Plus the guitar player's amp was open back, so the sound is spread around rather than being focused forward. Given those factors, plus how much everything was boosted into the hugh line array PA, I don't thing the ambient effect of the guitar player's 2 twelve inch speakers had much of an influence on the setting of his channel. His guitar would have drifted into the ozone if it hadn't been mic'd.
However, if we consider that the mic on his speaker was probably hearing a good 100 plus dbs (perhaps much more), and the singer's vocal mic was probably hearing much less, maybe 85 or 90 dbs (???), it seems easy to understand why the guitar channel was set much lower, so it all balanced in the FOH setting. That seems like a much more plausible explanation for the disparity in the FOH mix. That's why I started this thread by emphasizing the volume that counts; what the mic hears.
So if the mic on the guitar cabinet can be given less input, and brought down to something closer to the vocalist, then one is liable to get a better mix in this kind of situation. Dropping the guitar 6 dbs or more at the microphone (by use of a 4x12 cabinet &/or a lower wattage amp), seems like a good start, and the ambient effect of a louder 4x12 cabinet would seem to have little impact on reaching back perhaps several hundred feet to the soundman, particularly when driven by a low watt head.
_________________
It don't mean a thing if it ain't got that swing. |
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Lane Gray
From:
Topeka, KS
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Posted 9 Jul 2014 8:24 pm
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That almost makes sense, but I'd think that the house mix would be based on outputs, not inputs.
I half suspect the recording might have come from a monitor send?
_________________
2 pedal steels, a lapStrat, and an 8-string Dobro (and 3 ukes)
More amps than guitars, and not many effects |
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Stephen Cowell
From:
Round Rock, Texas, USA
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Posted 9 Jul 2014 10:09 pm
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If you want to be quiet on the board recording, point your cab at the mixer board. If you want to be loud, point it away. Perhaps there's a sweet spot, somewhere in between.
Or have a sub-mix done by someone with headphones on, that's the way the big boys do it.
_________________
New FB Page: Lap Steel Licks And Stuff: https://www.facebook.com/groups/195394851800329 |
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Shorty Rogers
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Posted 10 Jul 2014 8:16 am
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| Was the PA mix that went to the video pre or post EQ? It makes a big difference. I'm guessing it was pre EQ. Post EQ should have the video hearing what the sound person heard. Pre EQ would give the mix of levels coming to the board. |
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Dave Grafe
From:
Hudson River Valley NY
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Posted 10 Jul 2014 11:08 pm
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| Quote: |
If you mic only one speaker on a 4X12 (or 4x10) cabinet, then that one speaker is only getting 1/4 of the amp's power, so even though the cabinet is louder overall (when standing anywhere close to it), wouldn't the signal going into the mic not be as hot as it would be if the total power of the amp was going to a single speaker that was mic'd?
Assume same amp head, all impedances are correct, same microphone and mic placement (close mic'd), & same mixer/board on the PA. The only change is 1x12 vs. 4x12. |
Okay, I'll try again too  IF wired in parallel, for a tube amp the single speaker would be louder alone than as part of an array, but for a solid state amp it would be the same regardless. |
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Lane Gray
From:
Topeka, KS
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Posted 11 Jul 2014 5:00 am
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Dave, are you saying that a single speaker as part of an array would be as loud as a single speaker on its own if driven by transistors?
Explain, please.
_________________
2 pedal steels, a lapStrat, and an 8-string Dobro (and 3 ukes)
More amps than guitars, and not many effects |
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Steve Collins
From:
Alaska, USA
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Posted 11 Jul 2014 10:44 am
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| Your uneven mix in the video could have absolutely nothing to do with speakers, cabs, mics, size of venue, loudness, gain, etc etc. There are lots of ways to send a mix from the board, and simply tapping the FOH main mix doesn't mean a balanced mix. The FOH is the mix that sounds best to the ears in the venue, could be an entirely different mix needed to go to tape. Unless the sound tech is mixing a feed specifically for the external recording device your mix could be way off. |
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Donny Hinson
From:
Glen Burnie, Md. U.S.A.
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Posted 11 Jul 2014 3:36 pm
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I don't really see the point of the question. Is this like the old "If a tree falls in the forest and there's no one to hear it..." thing? 
Look, maybe I'm missing something, but if you want something to be louder than so-and-so, turn up the amp, the PA, or both! 
And if you've got everything turned up all the way, and it's still not loud enough...you wouldn't want to hear it anyway, because of the distortion. |
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Stephen Cowell
From:
Round Rock, Texas, USA
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Posted 12 Jul 2014 6:27 am
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| Lane Gray wrote: |
Dave, are you saying that a single speaker as part of an array would be as loud as a single speaker on its own if driven by transistors?
Explain, please. |
Note the 'in parallel' part... as well as 'transistors'. When you parallel another speaker in, the transistor amp's output goes up to keep the voltage the same. When you connect four speakers you normally use series/parallel wiring, so the impedance comes out the same as one speaker... so the power per speaker goes down.
None of this is relevant to the balance of a board recording... it's all in the engineer's control. If he's not doing a submix with headphones, then you are at the mercy of the live board sound, determined by what the engineer hears at the board. If your lead guitarist is too loud on the recording, have him point his cabinet at the board and turn up... he'll probably like doing that anyway.
_________________
New FB Page: Lap Steel Licks And Stuff: https://www.facebook.com/groups/195394851800329 |
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Lane Gray
From:
Topeka, KS
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Posted 12 Jul 2014 11:12 am
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| Donny Hinson wrote: |
I don't really see the point of the question. Is this like the old "If a tree falls in the forest and there's no one to hear it..." thing?
Look, maybe I'm missing something, but if you want something to be louder than so-and-so, turn up the amp, the PA, or both!
And if you've got everything turned up all the way, and it's still not loud enough...you wouldn't want to hear it anyway, because of the distortion. |
Donny, if you read his replies, upon listening to a tape off the board, steel, bass and guitar were low in the tapemix. The question, I think, was "how can I have an effect on this?" and I don't think we can.
_________________
2 pedal steels, a lapStrat, and an 8-string Dobro (and 3 ukes)
More amps than guitars, and not many effects |
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Dave Grafe
From:
Hudson River Valley NY
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Posted 12 Jul 2014 11:56 pm
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| Thanks Stephen, what you said |
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Kevin Raymer
From:
Chalybeate, Kentucky, USA
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Posted 13 Jul 2014 12:18 pm
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My kingdom for a good sound"person"......
_________________
Kevin Raymer
Zum / Knaggs / Breedlove
Fractal Audio |
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Kevin Raymer
From:
Chalybeate, Kentucky, USA
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Posted 13 Jul 2014 12:22 pm
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Not really that this applies, but....
I saw Styx one time at the old Starwood Amphitheater in Nashville and the had NO Amps on stage..
That would be a sound person's dream....
Total control of FOH..
_________________
Kevin Raymer
Zum / Knaggs / Breedlove
Fractal Audio |
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Dave Grafe
From:
Hudson River Valley NY
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Posted 14 Jul 2014 9:22 am
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| Quote: |
| A band I play in recently played at a large outdoor amphitheater with a very high end and large PA. One of the benefits of the gig was we would get a video of our performance with TV quality cameras, etc. But when we got the video the lead guitar player was way too low in volume, and the bass and my steel were somewhat too low. I asked about adjusting the volumes and was told we couldn't because the audio was simply a feed from the FOH mix. The FOH soundman did a superb job in the mixing of the headliners so I have no reason to think he screwed up. Plus all our fans in the audience said we sounded great. |
This entire discussion is a red herring. The recorded board mix was uneven because the bass, lead and steel guitars were louder off the stage than the other instruments and vocals, thus the sound tech had to keep them at a lower level to create a balanced audience mix. IF you want a balanced board mix you must balance your collective stage volumes, i.e. turn down the instruments - not the signal to the PA but the on-stage volume of the amps - that you want to be louder in the mix.
Also, even at 200' (really?) from the stage, if an amp is pointed directly at the sound mixer it will most likely not make it into the mix, as open back or not, any multiple-speaker amp turned up at all will have an on-axis beam that will slay dragons at 100 yards, and the sound guy will think it is loud enough, even though a few feet either direction it cannot be heard at all. Experienced players always take care to keep their amps turned off-axis to the mix position.
That's all there is, there ain't no more.... |
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