Crown PCC160

msawyer52

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I'm a volunteer for a local HS and have been helping them with productions for about 20 years. I've helped in all aspects including set, lighting and sound., jack of all trades, master of none. We recently discovered 3 Crown PCC160 mic's buried in their inventory. We're trying to use them for the first time in their current production for live stream and in house audience. We're feeding the mic's to a FOH mixer and sending that feed to the main board. The problem is that the mic's are so sensitive we're struggling with GBF issues. The main board gains and levels at 0 and we just bump the FOH gain to about 25% and the level output barely off the bottom to get output to the mains. Anything above that and we produce feedback. One issue might be is that the stage edge has been push forward so that the mic's are right under the main speakers, about 30' above. I have little control of the gain or output levels at this setup, any suggestions? Thanks.
PS - there are no PAD switches on either mixer, can I put an inline attenuator to lower the levels?
 
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themuzicman

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1. What are you trying to get out of the PCC's exactly? My typical argument is that PCC's are good for getting walking noises and not a ton more - despite what others say about them being useful for picking up dialogue in plays. PCC-160's are my mic of last resort for this, great for picking up tap dancers, bad for picking up people talking. Great if you set them on a table of an interview to pick up dialogue that way, bad if you are setting them on the lip of the apron and trying to get some vocals.

2. Why not just run them directly to this "main" board? Can you go into more detail on the setup of your space, and what differentiates the FOH Console from the Main Console? Which console is actually being mixed from during performances?

The first suspect here is that it's a gain structure issue and not necessarily an issue of the PCC being too close to that speaker but we can't rule that out entirely. If you are submixing from the first console and shooting direct outs into a second console you have to remember that the signal is exiting the first console at line level and entering the second console again at line level (as opposed to mic level).

You'll want to mix the PCC like you'd mix any other mic - actor proximity to PCC changes input levels at the mic, you'll naturally need to mix the mics to keep a consistent input level. Also remember that a PCC isn't a panacea, it works best on sounds in its immediate vicinity, but if you're using them on the apron in hopes of getting dialogue 20' upstage, you're already fighting a losing battle.

Let's take a quick moment to discuss how you are setting gains - lets reduce it down to a single console, a mic, and a set of speakers. You want to keep the fader at unity, remember a fader is logarithmic. By keeping a Fader at unity it is in the center of its range where it is the most sensitive - a 1/4" of movement at the bottom of the fader can be 9dB, a 1/4" of movement at unity might be 2dB (measurements may be off, but you catch my drift). From there you gain up the preamp until you are getting the healthy level you hope for. Looking at your output meters, if they are barely registering then you need to gain down your amps, trim the output, or take gain from somewhere on the output side so you can add gain to your input side so your meters register in a healthy range so you can get usable data off the meters. This is vastly oversimplified, but again I think you have a gain staging issue somewhere.

You don't need any sort of inline attenuator, that's what the gain knob on the console is for (or the fader).
 

msawyer52

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First, we're trying to add to the chorus for the main purpose of streaming but also a reinforcement for the live audience. The stage is 40' across with the mic's spaced at about 12'. We are running 14 Shure ULX for the main characters in the cast. The ULX are running from an antennae distribution to the main board back of the house. We have only 2 stage inputs and one is being used for orchestra playback since we are not using a live orchestra. Not enough inputs and we have no snake to make the run but do have the secondary mixer. I forgot that means line level from the FOH to the Main mixer.
We normally try to run at unity on the faders with the appropriate gain for each mic input. I'm getting so much input on the main mixer from the FOH, the gain and fader are all the way down "0". The only level we have set is the FOH mixer, about 25% on the gain and just off the bottom for the fader. Realizing now that my input on the mic channel to the main mixer is too high, doesn't that have to be addressed? I can mix the PCC's and set levels off the FOH mixer with headphones but that level is way to high to pass it back. I can drop all the gains and faders on the FOH but now I have no real mix for the PCC's. Yes I think we have a gain staging issue as you call it, just don't know the proper way to address it. Thanks for the quick response.
 
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josh88

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The issue is absolutely also that they are under the mains. Even at 30' up, if they're 90 degrees above the mic they're on the edge, but still in the polar pattern. You'd have to move the mics up stage ideally and get behind the speakers otherwise you'll need to just carefully EQ. As musicman mentioned, great for tap dance but I always try to make a point that with PCC's or other floor set ups, you're only ever going to get reinforcement, not amplification... at least when it comes to voices. They're helpful to give a little boost but not enough for a drastic difference.

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DrewE

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Your main mixer doesn't have line level inputs anywhere? That would be most unusual if true. Not infrequently they'd be on 1/4" phone plugs rather than XLR connectors. (Some modern mixers do indeed not have distinct line and microphone level inputs, but instead have a wide enough range of input gain trim to accommodate either one. It rather obviously seems you don't have one set up like that.)

What are the models of the mixers you're using? Having fourteen channels of wireless microphones (very nice!) but only a sixteen or so channel mixer (pretty small!) seems rather curious to me...but schools are sometimes curious places.
 

msawyer52

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Thanks for the replies, Yes the mixer does have line level inputs. Just did the quick and dirty plugged into the mic inputs backstage forgeting that it was a line level source from FOH. Just need to adapt to 1/4" line level input at the mixer. My bad. The main mixer is a 24 channel but they only wired the house for 2 inputs from the stage. I asked for more when they revamped the system but was ignored. We are also running 3 Shure MX202 overheads much further upstage plus MP3 and CD inputs to the board. Josh, I'm concern also about the positon. If we can we'll move them back as far as possible. Thanks everyone, something to work on this week.
 
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RonHebbard

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Thanks for the replies, Yes the mixer does have line level inputs. Just did the quick and dirty plugged into the mic inputs backstage forgeting that it was a line level source from FOH. Just need to adapt to 1/4" line level input at the mixer. My bad. The main mixer is a 24 channel but they only wired the house for 2 inputs from the stage. I asked for more when they revamped the system but was ignored. We are also running 3 Shure MX202 overheads much further upstage plus MP3 and CD inputs to the board. Josh, I'm concern also about the positon. If we can we'll move them back as far as possible. Thanks everyone, something to work on this week.
Have you considered flying them on 18" < 24" squares of clear plexi then doing your best to light around them?
If not the PCC's, KM84's or CK1's??
Toodleoo!
Ron Hebbard
 

TimMc

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Where to begin...

"Unity" on a fader is different than the "U" that Mackie screened around the gain potentiometer. Repeat until you believe this: THERE IS NOTHING SACRED ABOUT 'UNITY' AS APPLIED TO THE INPUT GAIN TRIM OR AN OUTPUT FADER'S LEVEL. Disabuse yourself of thinking about "unity". It's one of those things that makes sense on first glance but fails the operational use test in many live reinforcement situations.
 

msawyer52

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Have you considered flying them on 18" < 24" squares of clear plexi then doing your best to light around them?
If not the PCC's, KM84's or CK1's??
Toodleoo!
Ron Hebbard
Interesting Idea, may look at it once I get the mixer levels working properly.
 
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themuzicman

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"Unity" on a fader is different than the "U" that Mackie screened around the gain potentiometer. Repeat until you believe this: THERE IS NOTHING SACRED ABOUT 'UNITY' AS APPLIED TO THE INPUT GAIN TRIM OR AN OUTPUT FADER'S LEVEL. Disabuse yourself of thinking about "unity". It's one of those things that makes sense on first glance but fails the operational use test in many live reinforcement situations.
The way I've always understood it, Unity gain is the point at which no gain is being added or subtracted. On the head amp potentiometer this means that there is no attenuation or amplification and on the Fader this means that it's sitting right inbetween the rails at 0 back when the faders had actual positive and negative voltage rails at the top and bottom.

On the output side unity is more or less a lie because all the amplification happens on the input stage, so when shouting throw the output fader at unity, we really just mean throw it to 0 and are using a colloquial term for the zero because to some mixers hear Zero and equate that 0 = off and to others 0 = center of the fader's range.

Am I getting this right? In a decade of professional mixing I've never had anyone tell me that Unity is a lie, but I've also never questioned it too deeply.

The issue is absolutely also that they are under the mains. Even at 30' up, if they're 90 degrees above the mic they're on the edge, but still in the polar pattern. You'd have to move the mics up stage ideally and get behind the speakers otherwise you'll need to just carefully EQ.
This is the part in which text-based mediums fail - we have to argue best practices without actual eyes on the thing! In an ideal world they'd probably move upstage to not be in the same vertical plane as the speakers, but even if they were 90 degrees under the thing, assuming that the speaker isn't pointed down or at a drastic down-tilt the mic is most likely still decently off-axis to the horn of the speaker (yes, making broad assumptions here). I tend to either throw PCC arrays or DPA 4061 in BLM mounts (stupid high budget fake PCC's) across the deck of all my musicals as the plan of last resort if RF goes down on an actor - 90% of the time this puts at least the center 3 directly under my center cluster. The honest key is solid gain structure, a touch of EQ, and the mixer knowing just how hard they can push those dudes on the fader. Mixing PCC's can be harder than mixing RF, and it's even harder when you're trying to not let the audience know there is one person coming in via PCC and the rest are on RF.

One other red flag I want to touch on real real quick - If the PCC's and MX302's are hot all the time they are going to phase like crazy with the RF mics. Someone needs to be charting blocking for the show and you should hang and place the mics where the bulk of the action makes them the most usable. That way when a scene kicks in where you need them you can ride the 1 or 2 faders appropriate to the zone you have action in. You'll always want the hanging mics lower than the director will think is reasonable (think low enough to anger the lighting designer unless they are real chill).
 
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msawyer52

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The way I've always understood it, Unity gain is the point at which no gain is being added or subtracted. On the head amp potentiometer this means that there is no attenuation or amplification and on the Fader this means that it's sitting right inbetween the rails at 0 back when the faders had actual positive and negative voltage rails at the top and bottom.

On the output side unity is more or less a lie because all the amplification happens on the input stage, so when shouting throw the output fader at unity, we really just mean throw it to 0 and are using a colloquial term for the zero because to some mixers hear Zero and equate that 0 = off and to others 0 = center of the fader's range.

Am I getting this right? In a decade of professional mixing I've never had anyone tell me that Unity is a lie, but I've also never questioned it too deeply.
That sound good to me! I tell the people running the board to push it to 0 all the time.
 
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RonHebbard

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Interesting Idea, may look at it once I get the mixer levels working properly.
With PCC's, the barrier is important.
Loudest sound arriving at the mic wins.
Nowhere is it carved in stone that the barrier has to be the stage floor.
Depending upon where your performers are and the nearest walls, the side / edge of your prosc', and / or the stage side of your prosc' may be workable options.
Toodleoo!
Ron Hebbard
 

josh88

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This is the part in which text-based mediums fail - we have to argue best practices without actual eyes on the thing!
Part of why I offered to go put actual eyes on the thing, but yeah for sure the angle of the speakers are going to reduce the issue. I'm SURE it cold get worse. I just mention it because I've ran into these kind of issues with floor mics under center clusters where even though the polar patterns are probably just barely skimming each other, it's still enough for some feedback to take off unless you're real intentional with what you're doing. That with the gain issues, it seems like multiple factors are compounding the problem.
 
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DrewE

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The way I've always understood it, Unity gain is the point at which no gain is being added or subtracted. On the head amp potentiometer this means that there is no attenuation or amplification and on the Fader this means that it's sitting right inbetween the rails at 0 back when the faders had actual positive and negative voltage rails at the top and bottom.

On the output side unity is more or less a lie because all the amplification happens on the input stage, so when shouting throw the output fader at unity, we really just mean throw it to 0 and are using a colloquial term for the zero because to some mixers hear Zero and equate that 0 = off and to others 0 = center of the fader's range.

Am I getting this right? In a decade of professional mixing I've never had anyone tell me that Unity is a lie, but I've also never questioned it too deeply.
Faders generally do (and did) not fade a signal between the positive and negative rail. All the signals in a mixer are centered around signal ground (midway between the rails), though of course varying above and below that with each cycle of the audio. Put another way, the signals are AC-coupled, not DC coupled. A fader, in its simplest form, would have the input signal at one end of the track, and signal ground at the other, and then the wiper would have a variably attenuated level of the signal; there is, of course, nearly always one or more amplifiers associated with it to boost the output signal, reduce loading on the input side, etc., and the markings on the front panel of the mixer show the gain and output levels of the composite system. If you have a VCA system, the faders (or at least the VCA groups) wouldn't be directly altering the audio, but rather affecting a control voltage to the voltage-controlled amplifier, and that control voltage range could be most anything internally but likely not the full rail to rail voltage of the equipment.

A decibel is a relative measurement, expressing the ratio of power between two things. One of those things sometimes is an accepted reference level, as is the case of dBm or dBu or dBV. Other times, it's comparing the input of something to its output, giving an amount of attenuation or gain. It's a bit of an unfortunate thing that mixers often have both marked in different places, and it may be a bit confusing to keep track of which is which. Faders (and similar controls, like aux sends) are most often scaled with their gain, so the 0 dB setting of a fader means that the internal signal level is unchanged, as could for instance be verified by comparing pre-fader soloing with post-fader soloing. The level meters are usually calibrated in terms of output levels.

For a microphone input, the gain control would (generally) not need to go so low as 0 dB, so any marking of "unity" gain is just an arrow that the manufacturer thought was useful to print on the case, I guess on the assumption that your microphones are SM58's or some such and have certain sensitivities. Such markings should, to put it diplomatically, "be given the attention that they deserve." The input gain gets set so that the maximum (loudest) input to the microphone produces appropriate internal signal levels in the mixer, such as by adjusting it whilst soloing the channel until the level meter is a reasonable margin below clipping/overloading, as determined by experience.

(In digital audio applications, 0 dB is very frequently taken to be the absolute maximum levels possible, where the range of sampled values in the audio is the full range of the digital word size being used. In that situation, the nominal signal levels must needs be well below 0 dB to avoid clipping.)

Yes the mixer does have line level inputs. Just did the quick and dirty plugged into the mic inputs backstage forgeting that it was a line level source from FOH. Just need to adapt to 1/4" line level input at the mixer. My bad. The main mixer is a 24 channel but they only wired the house for 2 inputs from the stage. I asked for more when they revamped the system but was ignored. We are also running 3 Shure MX202 overheads much further upstage plus MP3 and CD inputs to the board.
Hmmm...so you have 14 wireless microphones, plus 3 PCC160's, plus 3 MX202s, plus a (stereo) MP3, plus a (stereo) CD...that works out to 24 inputs, and your 24 channel mixer could accommodate them all directly if you only had an eight channel snake, doing away with the submixer and its associated gain staging headaches. In your shoes, I'd definitely be giving it the old college try to buy, beg, or steal something like a Hosa Little Bro:

Hosa SH6X2-50 50' Little Bro' Stage Box Snake, 6 XLR Sends, 4 1/4" TRS Returns | Full Compass Systems
 

TimMc

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The way I've always understood it, Unity gain is the point at which no gain is being added or subtracted. On the head amp potentiometer this means that there is no attenuation or amplification and on the Fader this means that it's sitting right inbetween the rails at 0 back when the faders had actual positive and negative voltage rails at the top and bottom.

On the output side unity is more or less a lie because all the amplification happens on the input stage, so when shouting throw the output fader at unity, we really just mean throw it to 0 and are using a colloquial term for the zero because to some mixers hear Zero and equate that 0 = off and to others 0 = center of the fader's range.

Am I getting this right? In a decade of professional mixing I've never had anyone tell me that Unity is a lie, but I've also never questioned it too deeply.
Your technical understanding is correct (in the analog world), it's not a lie, it's just not a sacred cow. Half of the problems I see new soundhumans have regarding gain staging is this inexorable belief that the knobs and faders must sit at "unity" or god will kill kittens, or the Allies will lose the war or something. Um the controls move for a reason, but the Myth of "Sacre U" dies hard.

And in all things audio, there are a couple of ways to do things and whether any of them is right or wrong is mostly determined by achieving the necessary outcome for all stakeholders rather than rigid adherence to dogma (largely created by a marketing department).
 

Jay Ashworth

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Well, sure, Tim. But as the guy *driving the board* during a live mix, Unity is *my first target for fading something in*, everything having been set during soundcheck to make that a good target. Sure, it's also a safe bet the channel strip is better behaved at Unity, but that's only part of why I use it as a target: I just have too many other things in my head to memorize a different target for each channel.
 

TimMc

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Well, sure, Tim. But as the guy *driving the board* during a live mix, Unity is *my first target for fading something in*, everything having been set during soundcheck to make that a good target. Sure, it's also a safe bet the channel strip is better behaved at Unity, but that's only part of why I use it as a target: I just have too many other things in my head to memorize a different target for each channel.
No disagreement... but one must be willing to move the input gain knob to get whatever input trim is needed to have the fader there. Ditto for the placement of the output L/R fader - it might need to be turned down (perhaps considerably). Note that my comments have been aimed at a *beginners assumptions*.

{mostly true story alert}

Job applicant with audio skool resume applies, presents self as killer mixerperson and all around wunder-kind. Company owner points to a console with tracks running, clears the existing mix and says "go for it" and leaves the applicant to deliver. Thrity minutes later and the owner sees the applicant struggling. Owner suggest that the input trims should be adjusted. "Oh," the applicant sighed, "our instructors always did that." {/mostly true story alert}

There is some kind of fear of failure that causes people to adopt rallying points like "Unity-ism". A few decades back it was all about the Damping Factor (which had nothing to do with the status of the rapping lady's cat) and it was a simple pitch, a bigger number that was somehome automagically delicious and builds strong bodies 12 ways. Not that damping factor is bullshit, but that it was something the marketing dept at Crown could grab and run with to set their products apart from competitors when the reality (like where the gain knobs should go) is less definitive.

Parting shot, not cheap but... remember that the company that made the marketing pitch for "unity" as some kind of a) feature and b) fetish also told us their products were made in the USA - and then they weren't.
 

RonHebbard

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Your technical understanding is correct (in the analog world), it's not a lie, it's just not a sacred cow. Half of the problems I see new soundhumans have regarding gain staging is this inexorable belief that the knobs and faders must sit at "unity" or god will kill kittens, or the Allies will lose the war or something. Um the controls move for a reason, but the Myth of "Sacre U" dies hard.

And in all things audio, there are a couple of ways to do things and whether any of them is right or wrong is mostly determined by achieving the necessary outcome for all stakeholders rather than rigid adherence to dogma (largely created by a marketing department).
@TimMc When you posted: "dogma (largely created by a marketing department)". I bet you remember when Ashly was destroying steel wool with their new series of MOSFET output power amps. Any minute, you're going to try and tell me all amplifier and speaker manufacturers aren't calculating their wattage ratings identically for ease of 'apples to apples' comparisons.
Toodleoo!
Ron Hebbard
 
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