Crown PCC160

TimMc

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@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.
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Ron Hebbard
Specsmanship is an extension of Mark Twain's "There are three kinds of lies: Lies, Damn Lies, and Statistics."
 
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Lyle Williams

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Pretty-well nobody implements variable-gain amplifiers. It's just not a practical approach to the electronics.

What you see everywhere are fixed-gain amplifiers with an adjacent attenuator.

So the knob or fader just controls an attenuator that limits how much signal makes it to the fixed-gain amplifier.

If your mic pre-amp is capable of 60dB gain and you have set it at "0dB = Unity", then what you really have is 60dB of attenuation from the knob/potentiometer feeding into a fixed 60dB of gain from the pre-amp.
 

RonHebbard

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Pretty-well nobody implements variable-gain amplifiers. It's just not a practical approach to the electronics.

What you see everywhere are fixed-gain amplifiers with an adjacent attenuator.

So the knob or fader just controls an attenuator that limits how much signal makes it to the fixed-gain amplifier.

If your mic pre-amp is capable of 60dB gain and you have set it at "0dB = Unity", then what you really have is 60dB of attenuation from the knob/potentiometer feeding into a fixed 60dB of gain from the pre-amp.
@Lyle Williams Aren't compressors, duckers, and limiters, examples of variable gain amplifiers?
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Jay Ashworth

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And I don't disagree with that either, Tim, though there, the issue is a bit more clear cut (at least as Yamaha's taught it to me): If you set the input trim so that Unity/0 is a good place for the fader, you almost guarantee that you won't overdrive the channel strip, which has lots of positive knock-on effects.

The only time the whole thing gets messy, really, is if you assign an aux mix, say, to a broadcast and give him an iPad to mix it for himself... or a multitrack into Protools... once you do that, you really have to relinquish control of the trims, so you'd better have gotten them right by then.
 

DrewE

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@Lyle Williams Aren't compressors, duckers, and limiters, examples of variable gain amplifiers?
They're more like voltage controlled attenuators, though they can indeed be implemented using a voltage controlled amplifier circuit. They can also be implemented directly as some sort of a voltage-controlled attenuator, e.g. a photoresistor (for the attenuation) optically coupled to a light or a properly-biased FET, perhaps in conjunction with a fixed-gain amplifier.

Variable gain amplifiers (as opposed to attenuators and fixed gain amplifiers) are not at all uncommon for the microphone inputs of mixers. There are good practical reasons for this, mostly revolving around signal to noise issues. If the attenuation is before the amplifier, then the input level to the amplifier will be only at the level of the least sensitive microphone supported, and thermal noise from the attenuator (and other noise sources) amplified with it to give a poor signal to noise ratio. If, on the other hand, the attenuation is after the amplifier, then the amplifier needs to have a very large output voltage swing to accommodate the full range of input levels, while still having good noise performance.

It is quite common for the line inputs to simply be attenuated and fed through the microphone preamplifier, though that's not universal. (For instance, on some models Allen and Heath uses a two-stage input amplifier, with coupled variable gain for both stages, and bypasses the first stage for the line level input.)
 

TimMc

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And I don't disagree with that either, Tim, though there, the issue is a bit more clear cut (at least as Yamaha's taught it to me): If you set the input trim so that Unity/0 is a good place for the fader, you almost guarantee that you won't overdrive the channel strip, which has lots of positive knock-on effects.

The only time the whole thing gets messy, really, is if you assign an aux mix, say, to a broadcast and give him an iPad to mix it for himself... or a multitrack into Protools... once you do that, you really have to relinquish control of the trims, so you'd better have gotten them right by then.
Having the fader sitting at -0- give the best 'fader resolution' - the spot where small changes in fader position produce small changes in level - a dB or 2 - as compared to near the bottom of the fader travel with a small change in position could result in 10-15dB of level difference.

Console gain staging is mostly a compromise battle between optimizing for lowest noise floor throughout the console to reach the expected input level of the device that follows, and the physical place the operator would like the controls to 'sit' so muscle memory works.
 
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TimMc

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That sound good to me! I tell the people running the board to push it to 0 all the time.
If they can't have the input fader sitting around -0-, there is too much gain elsewhere, either at the input trim or output fader... and that's why when I see those things "nailed down" because of a silly marketing campaign from 30 years ago, it pisses me off.

Now if you'll pardon me, Mr. Quixote and I have to sharpen the points on our lances...
 

Dan Fischer

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PCC mics can be great mics for adding room fill. We have had great experiences mixing PCC's into our rear house and balcony fills. They help pick up a lot of the natural stage ambiance lost sitting so far away from the stage. However if you want them into a main FOH speaker mix you will usually need to ring them out really hard to squash any feedback. If your theatre like most has some weird resonant frequencies those mics will find every single one! I agree with Ron, try a flat plane behind the speaker cluster(s) even if vertical. Another idea we had in a previous theatre I worked at we made custom enclosures to go around them to shield of the PCC's from the speaker clusters. Think of an open shoe box on its side just painted flat black so there is no light elections on them. This method helped us quite a bit.
 

msawyer52

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Feb 22, 2007
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Detroit
PCC mics can be great mics for adding room fill. We have had great experiences mixing PCC's into our rear house and balcony fills. They help pick up a lot of the natural stage ambiance lost sitting so far away from the stage. However if you want them into a main FOH speaker mix you will usually need to ring them out really hard to squash any feedback. If your theatre like most has some weird resonant frequencies those mics will find every single one! I agree with Ron, try a flat plane behind the speaker cluster(s) even if vertical. Another idea we had in a previous theatre I worked at we made custom enclosures to go around them to shield of the PCC's from the speaker clusters. Think of an open shoe box on its side just painted flat black so there is no light elections on them. This method helped us quite a bit.
Yeah, I thought about the shielding like your shoebox idea. Yes these are very sensitive to the room frequencies but like you said just trying to get a more natural sound of the production. Working OK so far. Thanks
 

Ben Stiegler

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Sf Bay Area
How about posting a passel of pix of your space, your r speakers as seen from middle of the house looking toward stage, etc. can't take too many. We can help you much better when we have more info, and sometimes we don't know what we are looking for til we see it
 

msawyer52

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Feb 22, 2007
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Sorry, I've moved away from the venue and don't get in as often. I will post pictures maybe in a few weeks when I get in. Thanks
 
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macsound

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Jun 15, 2018
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San Francisco, CA
2 Issues I'm seeing

1. Mic placement. Crown designed the PCC to be sturdy. Don't be afraid of moving it around, just make sure its not a trip hazard.
2. Gain structure. Lots has been said above but most importantly what Jay said. Paraphrasing: You set gain so your fader can end up at Zero so you know where to shoot for when you bring it up.
If channel 1's sweet spot was -10, ch2 -15, ch3 +5, ch4 0, you'd never remember how far to bring the fader up and end up with feedback on some and not enough volume on others.
You are adjusting gain to make your space sound good and work for your application and combination of equipment. You don't have the rules of broadcast, your mom or the government looking over your shoulder. If input 1 is too loud before the preamp, turn it down somewhere upstream of the preamp, don't just deal with it because you think you'll offend the console manufacturer that you didn't turn the knob to where they said you should.
That being said, don't run your power amps at 15% and the output of your console at 125%. Be smart.
 

BCAP

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Jan 4, 2017
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Ohio
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?
This is my opinion, please feel free to disagree.

I like PZMs. I've used them since the late 80s - my first pair were from Radio Shack, which were actually Crown mics, I believe. Didn't even have a balanced XLR connector on them back then.

I currently own a few Bartlett stage floor mics (Bartlett was involved in designing Crown's PZM line) which I use for theatre but only specifically for the purpose of tap dance microphones, and usually I use them for recordings mostly and not so much the sound into the PA system. These mics are very similar to the PCC160. When the PA system speakers are quite far in front towards the audience compared to the placement of the microphones, they can work better.

I used to use PZMs for recording piano where I would mount them in the lid, and recording sessions of live groups (like big bands) where I could put a set up a 90 degree plexiglas wedge and mount the PZMs to those. I had also used them for audience microphones. Personally, I find PZMs to be very challenging to use for live sound or theatre in any other aspect where they are going through a PA system. They would be an awesome conference table microphone, though!

If your PZMs are routed into a live stream (and only to a live stream audio input, not to the PA system) then try putting them on a plexiglas 90 degree array in front of the stage. I'm sure you will get an excellent sound from them. I wouldn't recommend putting them into the PA system unless you have a digital board and an EQ such that you could notch out a lot of feedback frequencies.

Best of luck.
 
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