Any way to do SQ<-->(SQ+AR84) without two S-Link or Dante cards?

SQ SQ General Discussions
1

Hi.

Right now, my primary live rig is an SQ6 with essentially all IO going to an AR2412 in a rack near the stage. Have a Dante card in the SQ6, but only use it in the studio.

I carry an Qu-SB as a backup mixer (never needed), and used it a few times at gigs with no need (or space) for the SQ6. The Qu-SB gets hooked to the 2412 in that scenario.

I don’t really love the Qu-SB for this purpose… no local UI, can’ t use my SQ6 show files/presets/processing SQ, etc., etc. It really wouldn’t work out at all in a mid-show panic.

So what I’d really like to do is to replace the AR2412 with an SQ-Rack, and use it as a stage box most of the time, via S-Link.

AFAIKT, this will be reasonably seamless, except no controlling the SQ-Rack’s preamps from the SQ6 surface. I can deal with that limitation. Failover (and small venue/no SQ6) scenarios would be much better. Could also do redundant recordings. All great.

Fly in the ointment is that the 16 local XLR inputs on the SQ-Rack isn’t enough, and I don’t want to keep carrying the AR2412.

I have an AR84 lying around that I’d like to use that for my ‘overflow’ inputs.

Actually would work out great with the way things are racked. But it has no S-link repeater port.

So…

  1. Buy an S-link card for the SQ-Rack and use it to talk to the SQ6… $

  2. Buy a Dante card for the SQ-Rack… $$$

Is there a third option? ie, is there any ‘passive’ way to daisy-chain S-Link devices?

And, disregarding costs, any functional benefits to Dante←→Dante vs. S-Link←→S-link for connecting a pair of SQ consoles?

Dante’s great in my studio, but I mostly view it as an extra thing to go wrong during a gig…

Thanks in advance for any insights.

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Ultimate both solutions should pass audio between the devices. There are some differences that should be considered before making a decision on which way to go.

SLink to SLink solution: Pros - It is definitely the cheapest option. It is also going to be the most reliable option IMHO, and the one with the least amount of latency. Cons: it is a “point to point” solution (meaning it can only route audio to/from the one attached device) which might limit your future expansion options.

Dante to Dante solution: Pros - it is a true networked solution which means you can route audio to and from multiple Dante devices without any issues. This could make future expansion possible. Cons: The cost of the card is substantially higher than the SLink card. It is also a more complicated protocol. This means that there is more that “can go wrong” that could prevent the passing of audio. I’m not suggesting that Dante is an unreliable solution as it is normally very reliable once the Dante network is stable, but there is no question that the simplicity of the SLink connection provides fewer possible issues. The Dante connection is also slightly more latent than the SLink connection. Both are so fast that it probably won’t matter, but the Dante connection latency is probably .5-1ms while the SLink connection latency is just a couple of samples.

So to sum it all up, The SLink option is the cheapest, but least flexible option. The Dante option is more expensive, but allows routing to more than one device which might be a factor in the future.

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Re: latency; an interesting one. I hadn’t thought that all the way through.

I’m assuming that by using an SQ Rack instead of my AR2412 for stage IO, that I’ll be adding an extra 0.7ms or so in both directions right off the bat. Correct?

Then possibly another 1mS penalty for a Dante link, (in both directions as well, correct)?

Adding that on top of my digital wireless mics’ latency (ca. 1.9 mS, IIRC)… sounds like 5+mS?

Seems easily enough to bother someone if I did an IEM mix back on my main console and fed it back to the stage through the SQ.

I’m not working with any acts with IEMs ATM, but I wonder if 4-5 mS will tick people off listening to wedge mixes? Seems borderline.

Having the option do use the SQ-Rack as a monitor mixer is a plus, but I really don’t want to be forced to.

I think that might tilt things further in the SLink–SLink direction.

Re: Dante on stage… it makes me nervous. I love and use it extensively in my studio and my house. My monitor, main playback, and surround DSP controllers talk with various DAW and playback PCs, and SQ6 via Dante. Various AES dongles and AVB-Dante bridges (for my remaining Presonus gear) have pretty much eliminated analog connections anywhere upstream of my amp racks, and in some cases inside them as well.

It’s amazing, and rock solid… except when it isn’t.

Once or twice a year a switch flakes out, or a Dante Controller (or Dante VSC) update goes wrong. Things get muffed up, and sometimes I can’t play music for a few hours, even with multiple PCs and the Internet at my disposal to debug it.

That’s the nightmare that has kept me from using it in live settings, at least so far. But given the amount of Dante gear I have, I should probably get over it.

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OK, more research and reflection, and I think the answer for me is,.. Dante←→ Dante.

I just read through Dante-and-Allen-Heath.pdf

It looks like on an uncluttered network with a low ‘hop’ count, you can set the Dante latency even below 1mSec. They’re talking about 0.25ms. I didn’t realize you could get it that low.

That doc has a picture of an Avantis in it, but if it’s true of an SQ, I think that’s in ‘it doesn’t matter’ territory.

Seems like I could route my Dante-equipped wireless gear to the SQ-Rack and the main console, so those channels would get to main board without the extra latency, whatever it is, of a Sennheiser Analog Out— SQRack Analog In—Tie Line—Dante Out—SQ6 Dante-In.

I have some XLR dongle transmitters for my Sennheiser gear, I think I’ll try to come up with a scheme to measure that… could be a bit of a trick until I have an SQ Rack, but I can think of ways to measure some of the pieces.

In any case, all of this would leave the S-link ports open for other uses. I just remembered that the DX012 has AES outs, so it could actually run my monitor/FOH processing fully digitally with 1U of space, and has a link port. I’d failed to notice that.

So lots of $$$$, but looks like if I ditch my ARs and go with DX, I could do everything I want with or without Dante.

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The lowest latency setting available in the A&H Dante card is .25ms, but that is “per card/device” at the very least which means you won’t actually see total transport latency times that short. I think a more realistic total Dante transport latency time is probably 0.5-1.0ms. If the Dante network is unusually large or complicated, the total latency times could be higher. Again, either way it is so short I wouldn’t worry about it, but it is more latent than the AR box’s DSnake connection (4 samples at 48k or .083 ms)or a GigaAce connection (5 samples at 96k or .052ms).

Furthermore, to go back and answer one of your original questions - using a SQ Rack for I/O on stage will not automatically mean you latency has increased by a full .7ms due to the SQ Rack’s processing latency. The .7ms system latency is measured from analog input, through all of the console processing, and back out as an analog output. Given that you will likely be using tielines which removes the digital to analog output conversion as well as cut out some potential Rack console processing, I would expect the added latency from the SQ Rack to be well below .7ms (I’m guessing around .4ms??). That being said, we are really splitting hairs here IMHO because we are already talking about sub 1ms latency times.

But total system latency does add up so it is something to consider overall. Just to give you some perspective however, your wireless mics will add far more latency than the entire “console” setup, regardless if you use the SQ Rack with Dante or not. Most people won’t think twice about the added latency of using a wireless mic, but we will stress out over the added latency of our console routing even though with the A&H systems it is a tiny amount of added latency.

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Rambling on a bit, sorry in advance. Just trying to convince myself to spend a lot of money :wink:

…Most people won’t think twice about the added latency of using a wireless mic…

My old Wireless rig was 12 Ch of Line6 (about 3.7mSec latency in “RF1” mode), and 8 Ch of Sennheiser G3.

One group that I worked with regularly had one member with an (analog) Shure IEM setup, and he was thrown off by the lag induced by the Line6 mic + the round trip to the board. I gave him an analog wireless handheld and he was OK. I think I was mixing them on a Qu24 + AB168 at the time. So maybe 5 mSec total between the board and mic? Too much for him.

But total system latency does add up so it is something to consider overall.

Yes.

I went with Sennheiser’s DX (vs Shure ULXD4D or ULXD4Q) to replace the Line6 stuff, at least in part because their latency is lower. So is the weight and cost per channel, which does matter a little bit by the time you multiply it by 20.

I thought of the reduction in the mics’ latency (and the SQ’s, when I bought it years ago) as putting some latency extra margin in the bank. Now I guess I can guilt-lessly spend the savings on Dante ;0)

None of my vocal acts have ever had a problem with monitor latency through wedges or sidefills, even using boards that were much ‘slower’ than the SQ. My monitor DSP isn’t lag-less either.

But I mix some ‘regular band’ shows with touring talent that is used to treatment somewhat above my pay grade. I’ve gotten good feedback (so to speak) but I was called out for “echo-y” monitors a few times. Typically by someone singing singing solo while playing something like an acoustic guitar.

I always suspected they were imagining, or at least misattributing, what they were hearing (especially since those folks were singing and playing into wired mics!) But you really can’t be throwing off the vibe at soundcheck by having that discussion with some guy/gal that’s stil groggy from their flight, so I’d rather desingnthe rig to minimize the odds of it happening.

I will say that this latency thing is a funny rabbit hole, and it doesn’t always work out the way I would think. For example, the Crown CDi 4|600’s I use for my monitor amps/processing take 1.8mS analog-DSP-analog, but are 2 mSec slower through their BlueLink inputs.

Using AES input on a a Crown iTech adds 3mSec vs analog input. Makes me wonder if my DriveRack Venues’ AES inputs do the same, which means I really wouldn’t want use a Dante–>AES dongle or a DX012’s AES outs if every last mS of latency mattered.

Apparent lesson: A/D and D/A conversions might not be totally perfect, but are really fast ;0)

I think being able to use the SQ-Rack as a monitor mixer would negate the whole worry, in any case. I always have another engineer with me at any show were that could realistically come into play, anyway. I could just rename him the monitor engineer, and get extra Brownie points ;0)

….. End of Latency Talk ….

I’m more interested in (re-)designing my rig so that it can do the following (some of which it does pretty well already…):

  1. Works Reliably

  2. Has a workable disaster recovery plan if any one piece of gear fails.

  3. Gracefully scales down to “Rack + iPad” mode for the 5-10% of my shows that either “pure sound reinforcement”, or are in super-cramped quarters.

  4. Fit into functionally-arranged racks of a size/weight that I can carry, without requiring a ton of interconnect wiring at load in.

  5. Doesn’t absolutely require an iPad or wireless to function.

My current rig, (with a Qu-rack sitting in the van somewhere as my supposed backup mixer) would be very compromised if my SQ6 went down suddenly. Especially if my iPad & WiFi weren’t in place and behaving well, which they aren’t always.

The current setup is also very reliant on the AR2412, which is racked in with the monitor & FOH processing setup. The plan if the AR (or my SQ6’s SLink port) were to fail is to drag the board up to the stage and connect to everything directly. Would look pretty low-rent, but better than silence.

Replacing the AR2412 in-kind with an SQ-Rack would mean it’s already wired in, and would certainly be a lot closer to seamless if my SQ6 dies during soundcheck, or I don’t bring it because it won’t fit into a venue. Big win for issue #3 there.

In the new scheme, the SQ Rack going down unexpectedly would be almost as bad as the AR2412 going down would be now… but patching around it would require fewer cable swaps if some of the inputs were already on Dante and already routed to both mixers.

If it were a all-wireless show, I’d drag the wireless racks up to the mix position, and patch the remaining analog inputs straight to the SQ6.

If the monitor rack had a DX012 in it, then I could just repatch the SLink from the (presumably dead, RIP) SQ-Rack to the SQ6, fiddle with the digital patching on the SQ6, and I’d be good on that end.

Seems like I just need three Cat6 cables in my main mix-to-stage bundle, vs. the two I have now. Three would give me redundant Dante + a control network connection for normal scenarios, and Primary Dante + SLink + control if the SQ-Rack were to go down.

Hmmm… no need to move the mixer. I like it.

I think I may have typed just about enough text to convince myself that the expense will be worth it…

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There are no right or wrong answers here……

For complete redundancy you would need two consoles and two sources of local I/O for the stage. The benefit of the SQ Rack is that it can act as both a console and a local source of I/O on stage. I would recommend that you keep the stage box as a “backup” in case the SQ Rack went down however. It would allow you to plug the stage sources into the stage box without having to drag your FOH SQ to the stage.

That being said, I think using a SQ Rack on stage in leu of a stage box is going to be mildly frustrating for normal day to day use. That is because the preamp controls for all of the “local” inputs plugged into the SQ Rack will have to be controlled using the SQ Rack. That preamp information is not going to “carry over” to the FOH SQ like it would if you just had a stage box on stage. Anytime you needed to change the preamp settings, you would have to log into the SQ Rack using a tablet or other device. It’s not the end of the world, but it’s not as seamless as being able to change it in the FOH SQ like you would using a stage box.

So while I totally understand and can accept the idea that the SQ Rack offers some redundancy and flexibility from not having to take a larger SQ system to every show, the preamp control “issue” is certainly something to consider. I think it would be easier to set up a normal show using the FOH SQ console and the stage box and just have the SQ Rack as backup in case one of those two items failed.

Obviously you would have the flexibility of using the SQ Rack by itself for smaller shows as well.

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That being said, I think using a SQ Rack on stage in leu of a stage box is going to be mildly frustrating for normal day to day use.

Agreed. Futzing with an iPad for gain, etc, control isn’t ideal. See my recent post re: “StageBox mode” over in the ‘SQ Feature Requests’ section ;0)

But… a really big chunk of my shows nowadays are acapella concerts with all the on-stage inputs coming from my wireless gear.

This makes the gain management issue a lot easier to swallow. Once I get the preamp gain dialed in for my baseline show files, I think I can live with using a few db of digital trim at the main desk for performer-to-performer variations.

But yeah, for ‘real band’ work, and other things that don’t fit my standard format, I should probably keep at least some of my AB/ARs around, or ditch them and get a DX or two.

Re: backup IO: It just hit me that I still own several 24x4 & 24x8 analog snakes.

I’ve proudly/frequently stated that I’ll never lift/carry/use one of the 150’ monsters again… but your comment made me realize that leaving one in the van as a backup would be a cost-free option.

And certainly a lot less goofy-looking than dragging the main desk up front!

Tony

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I promise I’m done beating this dead horse… really ;0)

But two things occurred me this morning, almost simultaneously:

  1. XLR ←→ RJ45 break-in / breakout boxes could convert the two mixer–>stage Cat6 cables intended for Dante into an 8 ch analog snake. This could carry LR & monitor mixes to the stage in case of a Dante or SQ-Rack meltdown. Drag the wireless racks back to the mix position to take care of the inputs, and I’d be back online, at least for the vocal shows.

  2. If I keep adding stuff to my mixer ←→ stage cable bundle, it’s going to add up to the same weight and bulk as that 24x8 snake I so happily retired when I first went digital :face_with_open_eyes_and_hand_over_mouth:

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