Really Really new to this and having problems

[Greg Copeland]

I'm with a small community theater. Until a little over a week ago I've spent all my time back stage, building, stagehand, etc. I've been asked to do sound for the show we have coming up. The show, like most, has sound effects and music. We have a CD player and when I asked what we had for sound effects I was told we had a crappy PC that didn't work right. When I turned on the PC I expected a mess and was actually surprised to find a pretty good little machine. It's a AMD 2600 with 1gb ram, CD player (not even RW), a 40gb HD and a Diamond Extreme 7.1 sound card. The box has a clean install of XP and no other programs installed except the sound card driver suite and two other sound cue software trials that have timed out. I have installed SCS 9.5.2 Pro, not the demo. Examining the card I see the sound card has 3 stereo line outs. The diamond suite has the card set up for 7.1 surround sound.

For this show I want to come out line 1 to the house mains for music and 1 or 2 SFX's. Line 2 is to go to an offstage monitor house left and Line 3 to another offstage monitor house right for sound effects that play on one side or the other. In the production properties I have set up the sound device names used in cues as MAIN, LMON, RMON. The physical device is set to the Diamond Extreme. The speaker selection for MAIN is set to Front Speakers. Up to now everything is working well. I went through all of the speaker selections for both LMON and RMON. I finally got speakers to work with each but now I get bleed into line 1 from line 2 and 3. I know the problem is not in the soundboard, I used PC speakers to set this up prior to putting it up on the board for todays run through. The problem exists there, too. For the run through I just turned the level down on the monitors until and only when I needed them.

My questions are:
Should the sound card driver software suite be installed?
Should the sound card be set for 7.1 surround sound?
Are there settings for my card that I may be missing?
Are there settings in SCS that need to be set?
Any other things to look for?
Are there any other pieces of info you need to help me ?

Other than this the software is fantastic, easy to learn and easy to use.

Thanks,
Greg

[SimnaWeb]

Are you using a mixer after the computer and before the speakers? It sounds like you are becoming victim to unbalanced audio. It's the cable. You should keep the cable runs from the computer to the mixer as short as possible or if you really must skip the mixer put a DI box on each line of audio to balance the circuit and reduce noise and bleed.

[Greg Copeland]

Yes. The outputs go to a mixer. As I think back on the problem when I first tried it with the PC speakers it worked fine. It wasn't until I patched into the mixer and went to the house speakers that the bleed over occured and then it happened even with the PC speakers later. The cables from the PC to the mixer are 2 meter. For each of the outputs I'm coming out of the back of the card with a 1/8 stereo mic to two RCA connectors. For the Mains The RCA's are each connected to a 1/4 mic and plugged into two seperate channels, for left and right. LMON's two RCAs are connected to a single 1/4 mic and plugged into one channel in the back of the mixer. RMON is set up th same and goes to another channel in the mixer.

What is a DI, where can one be found and what is the usual price range?

[SimnaWeb]

I would check your assignments on the mixer. Sounds like maybe you might have some overlap. What mixer do you use?

If you are using a mixer and cables that are only 2m then you should not have bleed issues unless the cables are REALLY bad. In your setup, you should not need a DI box.

A DI box is a device that converts unbalanced 1 conductor + shield cable into 2 conductor +shield. It helps minimize noise pickup in cables. They come in all price ranges, from $20US-several $100. A good quality one is here: http://www.audiopile.net/products/DI_Boxes/DI_Boxes.asp

Mike, you are better at explaining this than I. I can do it, but explaining it over the web is not my strong point.

Eric

[Mike Daniell]

Just to add a bit to Eric's replies, a DI box is a 'Direct Injection' box. They are used mainly to connect musical instruments to the sound system, but are also recommended when connecting a computer sound card to the sound system if the sound card (or breakout box) has unbalanced outputs. If input signals to your sound system have to travel any distance, eg from stage to sound booth, then you need balanced connections or you will get mains hum and other interference. For short distances, eg just routing within the sound booth, unbalanced connections are usually OK if you keep your signal leads short and as far as possible from power leads. It also helps if you have a sound card that can send +10dB signals instead of -4dB, which most domestic cards send.

There is possibly another issue. I find that "surround sound" cards do not always get good speaker separation. Going back to your first posting, Greg, I recommend you do set up the sound card for 7.1 sound. In your Production Properties in SCS I suggest you leave the speakers field blank for MAIN and take this output from outputs 1/2 ("Front"). For LMON select "Output 3" in the Speakers field, and for RMON select "Output 4" in the Speakers field. Make sure you only play mono files to LMON and RMON. There is a possibility that outputs 3 and 4 will be switched with outputs 5 and 6, so if you don't get LMON and RMON sounding try changing to outputs 5 and 6 or alternatively change the physical connections to 5 and 6.

[Greg Copeland]

Simna, Mike Thanks. I'm out of the theater for the day but you gave me something to look into the next time I'm there. One additional thought I have may just be the location of the PC and where the cables run. I can take a look at them being seperated more and away from other electronics. Also Mike the idea of using mono files sounds like a good idea. I'll definately try that. Thanks again to both, I'll let you know how it works out.

[jkowtko]

Mike, he does not want to turn on a hardware surround emulator though, right? If he does this, the card will take a stereo input and convert it to 5.1 or 7.1 surround, which would account for signal from one input channel "bleeding" to other outputs. So I would first make sure that all surround programs are turned off on the card.

Also, if the card's control panel gives you "bass management" capabilities, make sure they are all turned off, so that none of the full-range channels try to shift some of their signal over to an LFE output channel.

I agree, the cords should not make a difference here -- however I would suggest you buy a couple of HOSA cables to get a reasonably clean connection: http://www.hosatech.com/hosa/products/c ... p-159.html You can get these pretty cheap on-line.

And, if you decide you want to bag the Diamond card and move up to something better quality, I'm selling my theater's M-Audio Rev 7.1 card (as I've upgraded to the Delta units) ...!

-- John

[Mike Daniell]

Mike, he does not want to turn on a hardware surround emulator though, right? If he does this, the card will take a stereo input and convert it to 5.1 or 7.1 surround, which would account for signal from one input channel "bleeding" to other outputs. So I would first make sure that all surround programs are turned off on the card.

So that's what's happening No wonder I have so much trouble trying to use a 5.1 or 7.1 card and prefer a proper multi-channel device. I suggested setting 7.1 sound to make sure that all channels were turned on because I sometimes find the 'Speaker setup' is set to 'Desktop stereo speakers'. If Greg only needs 4 outputs then maybe the 'Quadraphonic speakers' setting would work OK. Seems like it's a matter of trying various speaker choices to get the best result.

[Greg Copeland]

I'm really getting a crash course in audio this week. I've spent quite a few hours searching the web on this in the past three or four days. I'm far from even considering myself marginally knowledgeable on the subject but with everyone's help I'm beginning to understand. I've got a little breathing room before the show opens and I think I'm going to look at creating mono files for the sound and reset the card to quadraphonic or 4 speaker and connect up that way. Jkowtko, right now, thanks for the offer on the Rev 7.1 but I think I'm going to propose the Delta 1010lt to the theater. If they shoot it down, maybe we can talk.

Thanks again.

[jkowtko]

Greg, if you're going to start stepping up beyond the home PC cards, you might consider going to balanced I/O to eliminate hum and improve your S/N ratio. You can get the Delta 44 and 66 for under $100 on eBay if you monitor the sales carefully, and the Delta 1010 for around the $200 range.
-- John

[Greg Copeland]

I started looking into the 66. It seems like a better choice. Thanks.

[Theatre III Sound]

Hello Greg,

I've been a community theatre techie for quite some time, but only in the last few months have I gotten involved with sound. That is to say that what I've written below may be way off, but describes what I discovered about SCS feeding a mixer through a PC sound interface. I don't know if this applies in your situation.

You didn't specify what mixer you have, but does it have pan controls? If so, I think that means that signals coming into the mixer are bussed across to the mains or auxiliary outputs on two lines proportional to the setting of the pan control for the given input channel. So, even though SCS has been set up to send a sound on one output, you could still get that sound coming out of 2 speakers due to the mixer.

For instance, my theatre has a 24 channel Mackie mixer that has 4 AUX sends as well as the main outputs. Each input channel has a pan control plus three buttons labeled "L-R", "1-2", and "3-4". If I want a sound to go to AUX 1 only, then the channel that sound is coming in on would need its pan control set all the way left and the "1-2" button down. For AUX 2, the pan control would be set all the way right.

Bruce

PS: I grew up in Scarborough just up the road from you and most of my family still lives there. I'm in Acton, MA now involved with 3-4 community theatres plus I do lighting for HS productions in the area. Glad to have a relatively close neighbor in this forum.

[Greg Copeland]

Bruce,

The mixer is a Mackie just like you describe only it's 16 channel instead of 24. I'll give the pans a try.

I'm at City Theater. I don't know if you ever were in it or when you were but it's been nicely restored. A really nice place to see a show. We're doing 6 shows this year so plenty of chances to see a show if you're up visiting.

[Austin R]

Greg:

My community theatre technical experience has been mostly in lighting but I am now getting more involved with audio. Here are some thoughts from my ongoing slog up the learning curve.

Since we started using SCS we have changed from a Soundblaster 7.1 card to an M-Audio 7.1 Revolution card and finally to an M-Audio Firewire 410 interface. The PCI cards never seemed to be fully reliable for us. The main problem was that we would occasionally "lose" a channel in mid show. Touch wood the Firewire 410 has performed flawlessly right out of the box.

We use a Mackie 1642 mixer. With the PCI cards we would send the 6 or 8 input channels to the mixer's mixed outputs and, as Bruce noted, always panned the channel either full left or full right as appropriate. I don't recall that cross channel interference was ever an issue.

To set up my current show I had a notebook connected to the Firewire 410 in the auditorium and then fed the unbalanced outputs from the 410 to the mixer over a 50', 8 conductor, unbalanced snake with no problems. I'm not recounting this to challenge the physics of electrical interference (although I'm a biologist ) just to note that sometimes you can get away with bending the rules. For running the show I am using a 6' version of the snake with all the hardware in the booth.

Also, rather than use the Mackie as a mixer, I have routed the signals from the direct outs of the first 8 channels directly to the amplifiers. Once the Mackie channel faders (and other gains and EQ) were set to suit the show I haven't had to touch them except to compensate for partial and full houses.

SCS is a wonderful programme. My current show runs about 90 minutes with 75 sound cues and 30 light cues. There is no way I could have done this without SCS.

Austin
(another ex pat Brit)

[jkowtko]

Two cautions/reasons to consider always having a mixer in between your sound card and the amp/speakers:

1) have a manual master shutoff that you can throw quickly if your sound card, or more likely your PC, goes berserk on you.

2) being able to connect a backup PC to use in case the primary fails, without significant interruption in the program.

I have definitely considered removing the mixing board from the equation, but due to the above two reasons I have always kept it there