I got a Shure FP33, and have been advised that simply going into the RCA inputs on the XL2 to get a line level signal might not work because the Shure's line output is to hot for the XL2's line inputs. If I want to still give them cam a better-than-mic level signal, what are my options?

I've also been advised going from the tape outs might work, or some kind of external pad.

I also have the Beachtek XLR adapter (DXA4C) that I kept when I sold my XL1s, which also plugs into the RCAs. I tried the mixer this way earlier, and it sounded fine, but I wonder if I had something set wrong. I always assumed (wrongly?) that the line switches on the Beachtek attenuated its inputs, since when I tried messing with it before when I had mics plugged into it, my signal would disappear when I flipped from mic to line. So setting those to line AND going into the the RCAs would be doubly attenuating the incoming signal, or something. I had the inputs on the Beachtek set to mic when I did my test. Couldn't go straight into the RCAs from the mixer because I don't have the correct adapters yet. I wanted to post here before I bought more cables.

Hi Josh,

The FP 33 has mic level outputs. Use them. Use the XL2 balanced XLRs and run at mic level. No worries. That's what I do with my XL2 and Sound Devices 442.

Regards,

Ty Ford

Aren't there serious benefits to recording line level? More head room, better s/n ratio? Do you like the Mic ins better 'cause they're balanced? I've heard that if you have a really short cable run between mixer and cam (less than 10 ft), this isn't usually an issue.

P.S. found a cable, and tried using the tape out from the FP 33 to the RCAs. It works, but in order to get the 1Khz tone to match -12dB on the XL2, I had to crank the XL2's pots almost all the way up. At a certain point, even as I continue turning them, the cam stops giving me more volume. So it seems the tape outs are a bit weak.

Josh,

Serious is a big word. I'm first an audio guy and then a video guy. I have had no problems with mic levels to my XL2. Balanced audio (with XLRs) is very useful.

Headroom is relative to the individual circuit, regardless of whether it's mic or line level. The same for S/N figures.

Many "line level inputs" are simply mic level inputs with a pad in front these days, instead of bypassing the mic preamp.

Incidentally, check the headroom on your FP33. Shure uses dBV (Outputs –31 dBV ) to measure the mic level out and the FP33 has more headroom than the +4 on the meter.

I'm thinking you should be able to set tone lower than -12 on your camera. I set mine at -20, but my 442 mixer has at least 20 dB of headroom. I set tone from the 442 mixer to -20 on the XL2. The 442 meters go up to +20. I set the 443 limiter threshold to about +16. That gives me 4 dB of safety and that's even a little more because the limiter catches peaks over +16.

The FP33 may have as much at the mic level as it does at the line level and that's +18 dB. So if you set your tone at -18dB, you'd run out of mixer headroom just as you ran out of camera headroom. Experiment and let us know what you find.

Regards,

Ty Ford

Thanks.

I always though higher-end cams were meant to average/have tone at -20, but cams like the XL2, DVX, PD150, etc. have crappier electronics than those cams, and hence a lower s/n ratio at any given volume level, so I though -12 was the target on these types of cams. There's even a highlight on the -12 on the XL2's meters, and I remember the XL1s had the same thing.

I'll have to investigate more deeply the other stuff you mentioned, because I'm not much familiar with the math side of audio. My knowledge goes about as far as "line level better than mic level" (or so I thought).

Josh,

Crappier is a good word; indicating the high end cams are also crappy, just not as much. :)

Some of this is a math game, but were I to set tone at -12, I'd have to be VERY careful of the level.

I'm not sure where the -12 thing got started. I do know how much swing an audio signal has and that if you can keep peaks at -3 to -6dB on your camera, you're getting the best audio you can get.

The older Shure mixers with their analog meters don't show continuous peaks. The newer mixers that Sound Devices make show both peaks and RMS (VU) at the same time. Peak is what you want to keep an eye on.

Regards,

Ty Ford

I don't know where the 12 thing came from either (as I said, I'd always heard it was because of the electronics in the prosumer cams, and their higher s/n ratio at any given volume, a situation where a -20 target might give you too much noise when the sound is softer), but I've been aiming to keep sound between around -20 at the LOWEST, to -12 average, letting it go into the -6 range for louder stuff, and if it goes higher, oh well, long as it doesn't clip!

when I (very occasionally) edit, I output with the same goals. . .-20 is about the lowest, -12 for loud but still normal speech, and shouting or the like can go to -6 or so.

You think if I let it average way down there at -20 on the XL2, it'll be okay in post?

That's not what I said. I said set tone at -20; not record with average levels at -20. Your peaks on the camera should be hitting -3 to -6 dB.

With 0 dB tone from my 442 mixer, I set the camera meters to -20. My mixer meters go up to +20. The 442 mixer meter goes from -30dB to +20dB. That means I have a usable dynamic range of -30 dB to +20 dB. On a quiet set with no one talking, my 442 meters are down around -30dB. An FP33 doesn't read down that far, so you haven't noticed. -30 to + 20 means a usable dynamic range of 50 dB. Obviously, you want to keep the level higher for any audio to keep it out of the camera noise floor.

I set the mixer limiter to catch any peak over + 16 dB. Some of the fast peaks will get though, but I still have 4 dB (the space between + 16 and + 20) before the camera clips.

I adjust the input trims and mixer knobs so my PEAKS are at +14 to +18 on the mixer. The VU (RMS) level is below that. How much below depends on the sound source. Among people's voices, the PEAK to RMS ratio varies significantly. With some folks the difference between PEAK and RMS is 4-5 dB. With others it can 8-9 dB. This is not while they are shouting and then talking quietly. It's while they are talking at a steady level. I'm sometimes amazed that we are all part of the same species.

Again, because the FP33 doesn't really show PEAK very well, you are unable to see what's going on. That's one of the many significant advantages of all Sound Devices mixers. Were I you, I'd start planning for a Sound Device 302 mixer. Your ears will thank me. :)

Regards,

Ty Ford

And let me add a note.

Last month we were using a new digtial video camera with XLR inputs. This camera had NO NUMBERS on the metering. I set tone at -20 to one of the dots and did my usual talk checks while listening to the camera return of the headphone output. (It's VERY important to listen to the camera and not just the mixer.)

The camera (which we hadn't worked with before) was clipping when I was running normal levels. Mixer output and camera input switch were set properly -- mic to mic or line to line, I forget which. Something weird was going on. Maybe we chose the wrong dot. WHO COULD KNOW!? The owners manual was not available.

The 442 outputs can be switched from mic to -10 (consumer line) to +4 (pro line). I switched from line level to -10 and resent tone, calibrating using the same dot. (I probably could have chosen a lower level dot as well and not switched to -10.) Bottom line; we got good level to the camera and I heard no clips in the camera headphone.

We further insured ourselves by recording a bit, playing back and listening. Levels were good. No distortion. Off we went while continuing to listen to the camera output. No problems.

Hope this helps.

Regards,

Ty Ford

The -12 thing is a bit odd really as the dodgy cameras such as PD150/70 etc are accctually very unforgiving of high levels and seem to break up (distort) before they should. Therefore they need the same headroom as anything else.

The idea of peaking at 8db above tone is that it reflects the fact that the old world analogue PPM meters were, although considered fast at 10 ms response time, actually letting through up to around 4 db and more when pushed. Therefore the dbfs digital world needed extra headroom.

I've tried running the levels hot and laying tone at -12 but it gets you in trouble as it leaves only 4db for compressor/limiter overshoots which is not enough. As stated above, 4 db is normal for the margin which the PPM fails to register. This assumes that one's PPM is set to the BBC standard of 10 ms response time. Personally I keep this even in software emulations of the PPM as it looks right. Once you are conditioned to these meters they have a certain feel to the rise and fall of the needles.

In conclusion - you are best to avoid the -12 thing. If levels are run proprly on a mixer to peak in the right sort of area then lay tone at -20 (-18 for us English) and peak 8db above as measured on the PPM. (Higher by 4 db or more in reality.)

Without wanting to stir it up or anything I personally find my SQN works well with the rca line ins on the XL2 XL1's which I have used but of course all set ups are different. That's sound gear for you. One day I'll have some issue maybe running unbalanced and then I'll eat my hat. (incidently I tend to run a 5 Meter coilly cable and sometimes a 10 Meter straight attached on to it so I guess I'm inviting trouble. Sounded better on my tests though.

Cheers.

Sorry, I misunderstood the tone thing, then. I always thought (apparently wrongly) that where you put the tone was where your average was supposed to be so, on a broadcast cam, you set tone at -20, and average at the same. I will correctly my thinking.


So, I can set tone at -20, still have stuff hitting -12 and -6, and everything's groovy?

The XL2 and XL1s have always behaved as it seems they should, for me, not distorting 'til 0.

Thanks.

I've found the XL2/1 to be better for sound than most.

Ok, I tried the -20/-18 thing, going from mic out of the mixer to the mic ins on the XL2, set tone at -20. I yelled into a ME66 from right next to it. Even when the mixer's pegging, and I can hear the distortion when monitoring out of the camera, the camera's meters still only show around -6, even as I yell louder and louder. What does that tell us?

I guess I always thought the point of tone was to sync the camera and the mixer in such a way that 0 on a mixer = a certain level in the camera (-20, -12, whatever), so that as you watch the mixer's meters, you know what the cam's getting.

-12 comes from post. quite honestly when mixing to -12 = 0db analog betaSP tape machines like that level. it means you've got about +3 to +6db of headroom from there. 1800's only show +3, but they can handle hotter.

so that said, I have a FP 33 and I run it at 28V. I've got 2 batteries in series of 10cells (using a custom hand built power system to also supply 12Vwith common ground for wireless) and when they come off charge, they are 28.5 V and drain down to around 22V when done. the mixer is totally different at these levels ! it has much more head room, and sounds MUCH MUCH cleaner. its almost clip free at that range. even a pair of 9V's drain down to about 14.5ish when near dead. if you are using an external 12-14.4V system, you'll have clipping in the mixer as you turn any of the channel levels up past 7 because at those voltages, the mixer is barely functional, and why I think people tend to dismiss it as not being as good as a SD mixer. you just have to juice it up.

so that said, my HD100 camera boosts mic level to line level, and those premaps are NOISY ! so I always run line level to the camera and then I get good results. it likes having a hot signal. other cameras as Ty said basically pad line down to mic, then pre amp to whatever the camera uses internally :(

a pair of 10db pads can be helpfull when you have clipping even though the switches are right, but the camera can't take a real line level. you really do need to play with some cameras sometimes and test.... and always listen to the camera return.

You're saying that with the mixer plugged into a wall socket, rather than running of batteries, it won't perform as well?

Also regarding the return, I don't really get how it works. . .the manual isn't terribly clear on it. It's the "mon in" switch right? But how do you set the whole thing up?

the mixer doesn't care if its a wall wart or battery power. what it wants is hot DC voltage in the range of 24-28V for best performance. a 12V wall wart or battery in that range is under volting the mixer and it won't even perform at spec at those voltage ranges. 9V batteries are ok, but are on the bottom end of the units performance range as they sink to under 20V for most of their run time. you could try the high end rechargable 9Vs. the 2 battery packs cost me about $30 ea and I charge them on my PAG charger. however, I did make a box to as master power. in the on position it supplies 28V to the mixer, and thru a 12V regulator, 12V to the lectros. in the off position is takes the batteries from series to parralel and feeds them out to a charging connector & cable I built. not a simple setup, but I put it together for a total of about $100 in parts, which was much cheaper then a SD 442.

as for the return, you take the headphone out from the camera and on the mixer end it goes to the MON RET jack. place the switch into the MON position and you'll be getting the camera audio back. you'll have to adjust the camera headphone level so that it matches in level between mixer and return. ideally you need a break away cable that sends 2 XLR's to the camera and returns the 1/8" stereo headphone back.

the mixer doesn't care if its a wall wart or battery power. what it wants is hot DC voltage in the range of 24-28V for best performance. a 12V wall wart or battery in that range is under volting the mixer and it won't even perform at spec at those voltage ranges. a 24V wallwart would work well but stay away from electronic switching power supply types unless its a well filtered output. power supply noise on this mixer will make it into the audio.

this mixer is quite dependent on the input voltage. its a real old school design depsite its modern surface mount board. sure should of did a internal power supply to properly handle this, but they didn't.

9V batteries are ok, but are on the bottom end of the units performance range as they sink to under 20V for most of their run time. you could try the high end rechargable 9Vs. the 2 battery I have packs cost me about $30 ea and I charge them on my PAG charger. however, I did make a box to as master power. in the on position it supplies 28V to the mixer, and thru a 12V regulator, 12V to the lectros. in the off position is takes the batteries from series to parralel and feeds them out to a charging connector & cable I built. not a simple setup, but I put it together for a total of about $100 in parts, which was much cheaper then a SD 442.

as for the return, you take the headphone out from the camera and on the mixer end it goes to the MON RET jack. place the switch into the MON position and you'll be getting the camera audio back. you'll have to adjust the camera headphone level so that it matches in level between mixer and return. ideally you need a break away cable that sends 2 XLR's to the camera and returns the 1/8" stereo headphone back.

The power thing sounds like I'd have to have someone build it for me. Kind of weird that the brochures for the mixer mention that it runs on two 9v batteries, if nothing but your setup is under-feeding it.

Isn't that cable called a "pigtail", when all three (two XLRs and a return) are together? Also, I often work as a one-man band. . .can't I just monitor directly of the camera from its headphone jack?

2 9V is what they measure the specs on, but in the manual and on the unit it states max volt as 30V. what they don't say is they skimped on the PS design and should of included a stepup up power supply to properly run the op amps in the unit. it was by trial and error that I figured this out as I found performance on a single 14.4V battery had problems with clipping.

the cable is called a breakaway cable mainly because they all have a connector on the camera end that allows a quick connect/disconnect. while you can get away with using a pair of XLR's in an emergency, you'll find its a real PITA after a while. if you have to move around a proper breakaway cable will pay for itself the first day out.

yes you can monitor directly from the camera headphone jack if you are next to the camera. normally if you are running audio, you're next to the mixer to listening to the return there makes sense. most breakaway cables have a 1/8 jack on the camera end to split the headphone out as most cameras only have one headphone out. JVC on the HD series cameras provides 2. can't imagine how they were the first to include such a badly needed feature

Couldn't I just band a two XLRs and a 1/8" to 1/8" (or the split) cable together with tape or something, and call it a break away cable? I only run audio insomuch as I usually have to when I do video. I'm not at all an audio guy.

for an emergency yes. trust me you'll really come to hate this if you move around a lot during a shoot day. its also posses a saftey hazard as far as not being able to disconnect with a quick pull of the multipin connector. always having this thing tied to the camera gets old really fast. even just moving around in the same room. if you make a cable like this, you have to disconnect 3 wires and a velcro band to hold it to the camera handle, then connect it again. repeat this more then once a day and a real breakaway will get up on your priority list.

if you want, you can get 7pin XLR's and make your own. if you google around I think you can find the standard pin wiring. Eng is the last name of the guy who makes cables based on the XLR7 and is based in mineapolis. you can also use Nuetricon connectors but the are hard to find and a bit expensive. there is ebay where I picked up a like new used cable for $150.

The kind of stuff I do is usually very stationary (ery?) and if we move, it's only every couple hours. I will look into it.

]Ok, I tried the -20/-18 thing, going from mic out of the mixer to the mic ins on the XL2, set tone at -20. I yelled into a ME66 from right next to it. Even when the mixer's pegging, and I can hear the distortion when monitoring out of the camera, the camera's meters still only show around -6, even as I yell louder and louder. What does that tell us?

>>>>You may be crashing the mic itself or the preamp input by screaming

. That the camera meters only show -6 is weird. You are using a pair of XLR cables, one for each camera input? (Sorry, just trying to ferret this out)

>>>>Some mixers have internal adjustments for different calibrations. I don't know if the FP 33 does or not. (Anyone?!)

>>>>You don't have the Camera ATT switches on do you?

I guess I always thought the point of tone was to sync the camera and the mixer in such a way that 0 on a mixer = a certain level in the camera (-20, -12, whatever), so that as you watch the mixer's meters, you know what the cam's getting.

>>>>Yes, that's exactly what's supposed to happen. I wonder if something's wrong with the mixer; meter out of whack or something

Or...does the mixer manual go into where to set the controls to send tone?

Shure's customer service dept. is very good. Call them and go over what you're doing to see if there's something you're missing.

Regards,

Ty Ford

The mixer was purchased used (one of the reasons I got it over a SD302), maybe I'll send it for service. Everything sounds fine, and I've seen other FP33s do this, where the meters don't seem to match what a camera meter sees.

Yes, I used two XLRs out, mic level, to the cam's mic inputs. Didn't have the ATT settings on.

You can adjust the settings for tone and limiters and several other things--but they're weird adjustments involving potentiometers and voltmeters, and except for a few DIP switches. The seller was certain none of the pots had been messed with.

The basic idea that it boils down to is that I WANT the camera to max out when the mixer maxes out? Or I don't?

the issue might be that the limiters have been turned down to something like +12 or even +8/6 to match a betaSP meter. try turning off the limiter on the mixer and see if it changes. I'll also say if you don't run the input voltage hot, the limiter can clip, certainly when run on 12-14V it will. if you are on 2 9v's you should be in ok shape

adjusting the mixer isn't that big a deal. if anything, you can turn the output pots fully clockwise for the limiters which is where they come from the factory. the meters are also adjustable and hopefullly no one messed with them. I'll also say, the meters on the 33 really won't jive with the camera outside of tone anyways. always watch the camera and skip the mixer meters as long as they aren't totally low or pegged high, its working ok.if anything the channel LEDs are the best indication you're good - they should flicker mostly on.

Good point! I will try that.

The mixer was purchased used (one of the reasons I got it over a SD302), maybe I'll send it for service. Everything sounds fine, and I've seen other FP33s do this, where the meters don't seem to match what a camera meter sees.

Yes, I used two XLRs out, mic level, to the cam's mic inputs. Didn't have the ATT settings on.

You can adjust the settings for tone and limiters and several other things--but they're weird adjustments involving potentiometers and voltmeters, and except for a few DIP switches. The seller was certain none of the pots had been messed with.

The basic idea that it boils down to is that I WANT the camera to max out when the mixer maxes out? Or I don't?

Exactly! Call Shure.

Regards,

Ty Ford

Ok, so with the limiter off, yes, the camera will max out with everything else set the same.

I would really prefer to stay with plug-in power, if I could--I rarely need to be battery operated on the gigs where I use a mixer. Can you guys recommend something external that will juice it with 24-28v, and not cause noise?

try ebay.

http://cgi.ebay.com/Universal-Laptop-90W-12-24V-AC-DC-Transformer-Charger_W0QQitemZ290235877508QQihZ019QQcategoryZ64471QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

although this is a switching supply which I'd tend to stay away from. try searching to 24V power supply transformer, ect.

Thanks. But if I find one that isn't a switching supply, it'll work as well as battery system feeding it hot voltage?

yes. its not that a switching supply can't make clean power, its that you won't know it until you plug it in :( so a basic transformer type supply is better, with a basic regulator.

Thanks. It's all Greek to me, so I appreciate the guidance. If I didn't mention it before, I'm using the PS21 external power supply so far. . .haven't tried batteries yet . Also, when I do the battery test (again, with external power, but it's supposed to give you a reading on either), which is supposed to tell you whether it's getting adequate power, the needle is right at 0. . .I don't know if Shure means for that to tell me it's too low (technically it's outside the happy power red zone, but just barely).

A friend of mine much more versed in electronics and audio matters took at look at the circuit diagram for the mixer (I guess this ships with the mixer), and tells me that though it can take up to 30 volts, everything is regulated down to 15.

I for one would love to see a circuit diagram of the FP33. are you sure its a 33 ? and not a 32 which is a different beast. AFAIK they have never put out circuit diagrams, certainly not with the unit, but maybe as a service manual. just because there are 7815 regulators doesn't mean its 15V. while thats what the regulator is putting out, op amps require negative voltage to work correctly so the difference between +15 and -15V is 30. knowing those TL082's that shure used, this would be near their max operational voltage.

I'll pass your circuitry question on to my friend. We tried the mixer with a 19v power supply he had, which based on his thoughts, would have provide plenty of juice. I noticed a few things--the little LED that was blinking red when I turned on the power with the PS21 power supply was now blinking green, and when I did the battery check, it was way in the red, instead of at 0, where it was with the PS21. So I guess that's good. I couldn't hear a huge sound difference, but those other signs seem to indicate that it does want a hotter power supply, even if not quite as hot as you state.

Yes, it is "shurely" (heh) an FP33, says so right on the front. I'm sorry, I can't find a tech diagram anywhere online. I have a hard copy, but this thing unfolds like a map, it's huge! It'd be tough to scan. If you want to seek it out, it's called "FP33 Stereo Mixer Technical Information". Maybe they'd send you one if you called.

You probably will get a little better performance using the RCA consumer line inputs, but I don't think it would be worth dealing with an unbalanced signal. I'd put barrel attenuators on the mic inputs and use that, so you can run a true line level signal. It's way safer when working around power cords and other things that can cause interference.

Even using the Beachtek XLR adapter to get the line level? I've tried it, seems to work fine. What kind of pad, for mic level? Where do I get them? How much?

I think using a Beachtek would be really awkward with the XL2. You want the ShureA15LA.

http://www.bhphotovideo.com/c/product/68603-REG/Shure_A15LA_A15LA_Line_Adapter.html

You may need two of them. Pricey, yes, but from what I understand you can't cheap out on an attenuator. The quality of the transformer can have an impact on the sound.

I usually tape the XLR cable to the handle of the tripod in case somebody trips on it. Because the attenuators are so long, it would be a lot of strain on the inputs if somebody were to jerk at the cable at a 90 degree angle.

Can you clarify, awkward how? Thanks.

Well, the XL2 is already kind of large and unwieldy. Balancing it on top of one of those Beechtek or other XLR adapter isn't something I'd do.

Ah. Well, I've always left the beachtek ok there, regardless of whether it gets used or not.

So, according to my tests, it seems that if I want to get my cam to max out when the mixer does (according to Ty), I actually need to set the tone higher, not lower. So, equating the 0 tone on the mixer to -20 on the cam causes the cam, no matter how loud I get, to max out at about -6; it simply won't go any higher without turning up the cam's pots. If I set 0 tone to -12, though, then the cam maxes out at -2 or so, about where ty said the peaks should be. I guess if I did it between -20 and -12, it would all work out. Or, if instead of setting the mixer's master pot to 0 for tone, I could set that lower as well.