Need to figure out some SAC system basics

[KeithAbbott]

Our church is looking at a project to move the sound person from the sound booth - where its veeerry difficult to hear what's really going on - to the floor. At the same time we're looking at upgrading our present 20+ year old 16x4 BIAMP mixer.

At the moment, our auditorium is 120x120x18 (though it may be resized to 100x100 to add some additional rooms) and our style/music is conservative southern gospel and tradtional. Our output setup is currently simple: mono house speakers, a set of mono foldbacks, stereo recording, and a mono out that drives speakers in the nursery in a different wing.

I began researching our options, which I originally thought were going to be another analog board, or a digital board. Then I began running across information about SAC and realized there was a third option in the mix.

We're in the very early consideration stage but at the recommendation of a friend, we were looking at the Allen-Heath GL2400 24 or 32 channel for the analog option. The cost of that, a long 32x8 snake, and a quality roll top sound desk could put us nicely along the way toward a digital/virtual solution.

My experience level with professional digital audio is 0: my analog experience is, frankly, not much higher. I wish to spend the church's money wisely and wind up with a solution that will carry us well into the future. SAC certainly looks like an option with the flexibility to do that.

However, in order to know where I stand, I have to understand all of the pieces so I can determine costs. If the cost gets too far beyond the cost of an analog console and expense of moving it into the auditorium, the board wont approve it.

I***8217;ve read through the FAQ and forum and didn***8217;t really find a cohesive, comprehensive description of all of the equipment needed, and the considerations in the selection of that equipment. Actually I didn***8217;t even find a basics of ***8216;here***8217;s the pieces, how they fit together, and what they do***8217;. (maybe another sticky?) Although the faq gives pretty good hints.

Based on what I***8217;ve read here, I***8217;ve made some guesses that I***8217;d to air them out before everyone and have you help me correct and round them out. And since I***8217;m a visual type person, Ive done a drawing (sorry) that I***8217;ll include.
Please correct and add anything that needs it.

In the drawing, I***8217;ve shown everything (that I know about so far) that is required to replace an analog console with a SAC system, in the light gray box.

The centerpiece ***8211;the one this forum is about ***8211; is of course, the SAC software which runs on a Windows-based PC ***8211; requirements covered in faq I believe, but fast single CPU is better than slower dual.

SAC provides the mixing console and signal processing ***8211; compression, n-gate, channel assignment, and a thousand (well 993) other things. Some features require additional plugins ***8211; some free, some chargeable. I***8217;m not sure what is what with the plugins ***8211; perhaps someone can list some examples to help clarify. The software and PC are shown roughly in the middle of the drawing.

There has to be some way to get the inbound signals from mics etc, and the outbound signals to amps etc, into the PC to be processed. This is the job of the audio interface card (internal PCI card as recommended by moderator ***8211; there seem to be external device offerings supporting firewire as well). For the purposes of the drawing, I specifed the RME 9652s since it was one suggested by the moderator. (A side note here that I read specs on the 9632 also and am starting to suspect I've mentally mixed up the specs of the 2).
This type of card supports 3 ADAT interfaces, which are optical interfaces ***8211; each of which can support 8 channels of audio in or out. There are other interface formats available (MADI for instance) but I don***8217;t know what the pros and cons are for using 1 over the other or if they will work with SAC (assumably so), or what alternate hardware would have to be used with them.
The card specs say that it can support 16 channels in or out (with expansion cards). I am not sure if 8 in and 8 out is possible on one card and I am not sure why there are 3 ADATs on the board since 16 channels could be supported by 2 ADATs. Also when I looked at the expansion cards, I didn***8217;t see any that were specified for the 9652 so I***8217;m not sure how you get to 16. I assume without the expansion card you get 8?
For the cards, there are specs for bit depth and sampling rate and I know the basics on those specs and the associated controversies related to bit depth. Without jumping into the argument, it sounds like its better to use 24-bit for mixing and recording (does that include even basic House of Worship live service recording where exacting results are not expected like they are in production recording?)
The Audio Interface cards are shown in the drawing as inserted into the PC. Since I don***8217;t know the story of what is required to get 16 channels per card on these, I***8217;ve shown 4 cards to get a 24x8 console. Hopefully someone can set me straight here.
One of the options for the board is a world clock. It appears that the clock provides special syncing of the audio signals. I am not sure if these are recommended, required, or only needed in special cases. If they are required or recommended, is it 1 per card, 1 per console, or some other measurement.

Finally, the Audio Interface Cards support digital channels ***8211; not analog, so there has to be an analog to digital converter for incoming signals from all those mics and junk, and a digital to analog converter for outgoing signals to all those foldback and house amps.
Again, the drawing shows one of the FAQ recommended devices, the behringer ADA8000. Each unit provides 8 ports of IO. Inputs have their own preamps. I***8217;m not sure what kind of overhead is available in the preamps, and if these inputs will universally connect to anything (phantom powered mic, non-powered mic, line level from playback devices and wireless receivers, laptops, etc) and I***8217;m not sure if each channel is independently assignable as an input or an output. I presumed so and in the drawing they are shown at the left edge of the ***8216;mixer box***8217; (the gray area) with some miscellaneous inputs and outputs connected.
The ADA8000s connect to the PCI Audio Interface cards via the ADAT interfaces. In the drawing, the bottom ADA8000 shows 2 ADAT cables connected 1 for input and 1 for output. This may be wrong.
Undoubtedly there are other devices supporting this function but I don***8217;t know what the recommendations are (other than if you***8217;re using an interface card with a MADI interface, your AD converters better support a MADI interface.

So that***8217;s it. The mic signal comes in to an ADA, where it hits a preamp ***8211; (I don***8217;t know how gain/atten is controlled in the preamp ***8211; if it is settable, fixed, or automatic).
It***8217;s then converted to digital and sent along the ADAT pipe to the PCI Audio interface card, which provides multiple channels for this type input.
The PC then provides mixing and signal processing ***8211; although it seems that some of this must be offloaded to the audio card since these cards are supposed to keep CPU impact to a minimum.
The PC then sends the processed signal out the audio interface card to a D/A unit ***8211; in this case still the ADA8000 ***8211; where it***8217;s converted back to analog and sent to the amp. I don***8217;t know if it***8217;s still recommended to have a limiter between the amp and ADA8000 as final protection for the amp and speakers or not.
There it is. I know it has to be full of holes and errors. Please help me correct my understanding and fill it out so I can move on to the next step of deciding what equipment we would need/use in our implementation.

(Sorry about the image - I really had to size it down to make it acceptable)

Thanks
K

[Bud Johnson]

You pretty much nailed it.
Mic > ADA8000, (gain is on the front of the unit)>light pipe>RME 9652 (9652 hdsp provide a virtual mixer between card and SAC which creates some options that may not be important to you. Also has a lower potential buffer setting of (X) x 32 where as the older 9652 only goes to(X) x 64. Hasn't ever been an issue for me.) RME > SAC, mix, assign outputs for FOH and monitors> RME >ADA8000> amps or powered speakers.
Plugins provided with SAC are Graphic EQ and Delay. I do highly recommend purchasing the Levelizer native plug ($100) as it will be a go to for limiting and compression with very low system load. Verbs are a plenty and there is a free one for SAC that is fine for monitors and FOH.
This system will provide for a world class sound and any necessary growth at minimal expense.

[Larry Burger]

I would include a laptop for remote control.
The remote does not have to be a monster just reliable.
It must include a wireless and you would need a wireless router.
This would allow you to keep all cable runs on stage.

[tatkin]

Keith,

I was in the same quandry as you and when I started looking at SAC v.s. ananlog and digital boards there was no comparison. I've put in one system and plan to replace our other Soundcraft board with a similar one.

You have everything right but I would add a few suggestions.
1) Go with an RME RayDat... you can expand to more channels as you find that you need them and it's a great interface. No problems with buffer sizes or anything else.
2) You will need to buy/build a PC for the host... stick with a good machine based on an E8xxx processor... I had no problem with them.
3) Figure on a step down transformer (look in this forum for specs) for the ADA8000s. They run MUCH better with it.
4) Plan on purchasing the RML Levelalizer and the Frequency Analyzer... They REALLY help. Stick to native SAC plugins as much as possible to minimize the strange effects of others.
5) If your sound booth is in a bad place (mine is too) plan on a laptop to run as a remote and let your sound guy sit where ever he wants... won't have to give up valuable congregational seating for equipment, just him and his laptop. Wireless connections work but wired is better.

I went from an A&H board to SAC and couldn't believe the difference in sound quality, flexibility and ease of use. My total system cost for 24 channels of ADA8000, RME-RayDat, PC, and all the misc extras was about 3500.00. You couldn't even start to match all that SAC does for that price any other way. I can easily add 8 more channels without much cost if I need to in the future.

Another great thing is the 24 independant mixers besides FOH. Makes it very nice for doing recording feeds, radio feeds, nursery feeds, etc, etc, etc. Your imagination is the limit. Remember... using the system I set up there are 24 inputs AND 24 outputs... more than enough for getting creative. I plan to eventually eliminate all the speaker processing hardware in my old rack and let SAC do it.

Training volulnteers takes little time and they aren't near as intimidated by a graphic on the screen as they are by 100s of buttons and knobs.

If you go with SAC you won't be sorry... just do your homework first.

[RBIngraham]

Keith,

I have some system diagrams for a few shows on my web site. These might help you along the way, although I am not using the RME products.

http://www.rbicompaudio.20m.com/past_projects.html

But you don't need multiple 9652 cards, one of those cards will take up 1 card slot (PCI or PCIe) and one blank plate on the back of the computer (in other words it takes 2 card slots, but one of the slots is just a plate for connectors and 1 is an actual card). Each 9652 card has 3 ADAT I/O ports, so it can handle up to 24 Inputs and Outputs. The 9632 only has 1 ADAT I/O port. I wouldn't bother going with that card frankly. Get one 9652 and you'll better off.

If you're looking for something to compete in the GL2400 price range, don't even worry about MADI, it's a lot more expensive. It allows for a lot of channels to be run down either fiber optic or single piece of Coax, but that's more of a digital snake than something you need to get audio in and out of the computer.

Also don't worry about the 24 vs. 16 bit thing. Almost no professional sound cards are 16 bit only any more. They can almost all run at 16 bit or 24 bit. And if you're looking at the RME products it won't be an issue at all.

Hope that helps.

[Brent Evans]

Keith, I went through the same process, you'll be very happy with a SAC setup.

First determine how many channels you need. The HDSP9652 handles 24, the Raydat handles 32. The older RME DIGI9652 handles 24, which is what I used, but I was spending my own money (very limited) and found a killer deal on Ebay. This card is no longer supported, so you have to stick with XP, which could be a problem in the future. Couple the card with as many ADAs as you need to get the channel count.

To give you a basic budget for a 32 channel system, based on various quotes and info obtained over the last year:

SAC and Levelizer: $600
PC: $1000 (can be done for less, this should include everything you need to be functional, including router, etc.)
Raydat and 4 ADAs: $1600
Remote Laptop: $500
Total: $3700

That said, it can be done for less, or more. It all depends on what you want to spend. If you have a laptop for a remote (or a desktop for a fixed FOH station, for that matter) you can trim that cost, although an extra mobile remote is handy. I have only about $1500 in my rig, but I have only 24 channels, already had remotes, most of the PC parts, found a killer deal on ADAS (Cal Mazzara at Full Compass) and got the RME on Ebay at a deal too.

The going rate on a GL2400-32 is about $2600, plus your snake ($500) and processing rack (over $1000) so even with no penny-pinching, you're still going to come out better, with much more capability. With the analog setup, you will have limited channel strip processing, and limited expandability. With SAC, you can process as much as you need, and expand as much as you need.

Couple of things I'd recommend - put a hardwired desktop remote at FOH with a large screen, it will cost about the same as a laptop, and then use either existing laptops or cheap netbooks ($300) for mobile remotes. This arrangement has worked out very well for us, as we already had a PC at FOH for recording. An upgraded monitor was all it needed to make a splendid remote.

[KeithAbbott]

OK, this has been some good info so far.

I definitely agree about the laptop. I had thought of it previously but not included it in the post.

The Raydat sounds like the perfect option - I was shooting for minimum 24 channels with 32 being preferable

The suggestions for the 2 plugins are also very helpful.

Thanks for the link to the diagrams Richard. I've started looking at them but need to go through the layout more closely to really see whats going on there.

I will take a close look at the step-down xformer suggestion. I don't know what's going on there but I'll track it down on the forum.

So it sounds like there is a 1 to 1 correlation between ADAT connectors and the number of ADA8000's a specific card can handle. I didn't know if it was 2 per ADA (1 in 1 out), or if they, put 'extra' ADATs on the cards for some purpose I wasn't aware.

I'd still like to know if on the ADA8000, the channels are assigned in or out on a channel by channel or unit by unit basis.

I also need to know about the world clock option and when it is or isnt required or recommended.

Im still not sure about the input limitations on the ADAs, either. Can they support everything from line-level down? Are there any gotchas I might run into or if it plugs into our old BIAMP should it be able to plug in to the ADA?

Thanks for all the input thus far. Things are getting clearer for me. The quick price guestimate was great too. It gives me an idea of the ballpark I'm playing in.

K

[RBIngraham]

Thanks for the link to the diagrams Richard. I've started looking at them but need to go through the layout more closely to really see whats going on there.

Just keep in mind that I'm doing theatre shows so I have 2 separate computers, one running SAC and another that is running sound playback software. So what you're seeing in the drawings isn't just the SAC system, it pretty much all of the sound system except that instead of putting symbols for the Amps and Speakers, I just put in text like "Feed To: Center Cluster"

So it sounds like there is a 1 to 1 correlation between ADAT connectors and the number of ADA8000's a specific card can handle. I didn't know if it was 2 per ADA (1 in 1 out), or if they, put 'extra' ADATs on the cards for some purpose I wasn't aware.

Yes, usually you would have 1 ADA8000 for each ADAT Optical I/O on the sound card. Each ADA8K has 8 preamp inputs that get converted to a single ADAT Optical output and one ADAT Optical Input that gets converted to 8 XLR analog outputs on the back of the unit.

I'd still like to know if on the ADA8000, the channels are assigned in or out on a channel by channel or unit by unit basis.

One the ADA8K themselves, yes analog input 1 is always channel 1 of 8 on the optical digital output and channel 1 of 8 on the optical input will always go to analog output 1.

But one you get the audio into SAC, you can patch any physical input into any or as many channels as you like. You could assign one mic input to all 72 input channels if you really wanted to do so for some reason. And the outputs work pretty much the same way, except that they are always dealt with in stereo pairs. On the inputs you can work in mono inputs or stereo pairs.

I also need to know about the world clock option and when it is or isn't required or recommended.

For what it sounds like you will be setting up, you won't need it. To fully explain the answer to your question with all the different possibilities would be a small white paper, not a simple post on the forum.

Im still not sure about the input limitations on the ADAs, either. Can they support everything from line-level down? Are there any gotchas I might run into or if it plugs into our old BIAMP should it be able to plug in to the ADA?

They will handle phantom powered or non-phantom mics just fine. You can plug a line level input to them. They have a 1/4" input and an XLR input, just like most mix desks do. I would suggest keeping some inline pads handy if you need to plug line level signals into the XLR inputs, they can clip easily with line level on the XLR even with the gain all the way down. If it's a really hot line level signal it will likely clip the preamp. But it should also deal with wireless mics just fine, CD players and that kind of stuff as well.

Just use proper gain structure, just like you would on any mix console.

[gdougherty]

Keith, glad you made it over here

See, lots of willing and knowledgeable advice around here. We should probably get your setup nailed down, where things will live and how they'll fit together before you put in a proposal.

The RayDAT is a solid choice. It's PCIExpress (a newer card standard that should be around for a good while) and it's a newer generation which should mean you'll be good for a few versions of Windows releases with driver support. It costs a bit more, but it has its advantages too.

The step down transformer is to run the ADA's on 100V instead of 110-120V. They have a poorly designed power supply that likes to die when it shouldn't because of heat damage. It's a $50 part that should keep all the ADA's running for quite a bit longer without problems. Cheap insurance for ~$800 worth of gear. If you call up Full Compass and ask them to give you a good price on the RayDAT and ADA's you'll get about the best pricing around on those units.

You've got a few options for cable configuration and host placement. The lowest cost will be what some have hinted at, which is to put the ADA's and the main system down onstage. If you don't have to touch your input gains during services that'd probably work fine as long as you have somewhere to tuck away the system where it can breathe and stay cool.
If you need to adjust gains regularly, you might want to consider putting the host and preamps in back and run things over a snake. You'll get the best audio quality from having the preamps onstage with short cable runs, but either way, SAC will still sound better than a GL2400 and snake. If you want to put the preamps onstage and run everything from the host (kind of nice since there are some plugins that won't run on remotes and don't support remote control) you can either go with 100' optical cables like we did, or you can purchase some ADAT extension units and run the signals from the preamp to the host over one or more CAT5 network cables. Either way you may end up needing to run signals from the stage and back if you've got video and audio playback inputs at the upstairs mix position. In that case, I really like the host upstairs with an ADA local and the rest of your ADA's onstage as long as you can live without gain adjustments close at hand.

Something to think about...

[sjpaul]

I own an A & H GL3300 and SAC, and while the GL is a good console, there is no comparison in terms of features and routing opotions. I take out SAC on 80% of jobs now, the analog consoles only go out when there's going to be a guest engineer mixing.

Depending on your budget, costs can be trimmed with used gear, e.g. my SAC host PC is an older IBM Pentium 4 3.4GHz and I picked up a s/hand RME HDSP9652 and some B stock ADA8000's, but if I was building a new system, I think I would go core 2 duo and a Raydat for 32 channels.

Definately go for the leveliser plugin. It's a fantastic limiter. There are loads of free VST plugins that work well with SAC, especially now that remote plugin access is available. The Kjaerhus classic ones are good and for a simple to use verb, I use Anwida's free DX lite. IMO you really won't need anything beyond SAC's included paragraphic equaliser for system output EQ with the ability to use multiple instances of it on outputs if needed, e.g., one for overall system EQ and another for small feedback cutting notches if needed.