Shure UA844+SWB and QLXD's

[flyweed]

Hey guys, hoping for some quick connection help. I just recieved my order of (5) Shure UA844+ and (18) QLXD mic systems. I've only ever worked with Sennheisser, so am new to the "connections" on the back of the Shure UA844's. I am connecting all (5) UA844's together, am I simply using the "Cascade" connection on each UA844+ to "jumper" them all together? And then each 4 RX units will connect to One A input and one B input on each UA844? Does each RX unit also connect to the UA844 for "power" as well?

Just trying to wrap me head around how all 5 of the UA844+'s connect to EACH other first, before I start plugging 4 mics into each one as well.

Thanks for any help.

 

[mbenonis]

@flyweed It's not recommended to cascade each UA844 down the line like that. Rather, use one UA844+SWB as the "head end" unit to feed the four other ones. Then connect the receivers to those downstream UA844's, so the signal has a maximum of two hops to get to the receiver. You can use outputs 1-4 and the Cascade port to feed a receiver. The only catch you may run into is that there are only four DC power outputs on each UA844, so you will probably need to power two QLX-D from the "head end" unit--or just use the wall warts (unlike Sennheiser, Shure receivers are not powered over the BNC connectors).

Here is a diagram from the Shure Wireless Accessory Wizard:

Remember to update the receivers to the latest firmware with Shure Update Utility, and then perform a scan and deploy compatible frequencies using Shure Wireless Workbench after you get these all racked up (use WWB 6.13.3 for best results, the TV database was updated from older versions in this release). Reach out to Shure Applications Engineering you run in to any trouble!

 

[flyweed]

So, if I am understanding this right...you use your FIRST UA844 unit (RF A and RF B outputs) to jumper to another UA844 unit (or multiple units)? Can I use the two Antenna A and B inputs on the first unit for my two YAGI antennas?? So there won't be any of my QLXD receivers connected to the first UA844 unit.?

 

[mbenonis]

@flyweed you've got that exactly right. Antennas A and B connect to the first unit, and then Antenna A and B signals from the first unit feed the second set of UA844+SWB units, which connect to the receivers. Each receiver gets a clean A and B antenna signal, flowing through two UA844+SWB units.

 

[flyweed]

Ok...think I got it. So for power to each receiver...does power come through antenna cable connections, or do I still need to connect DC power cords to each Receiver? and those in turn plug into the power ports out of the UA844?

 

[mbenonis]

Power is a separate cable. Shure receivers do not get power from the antenna connections like Sennheiser devices do. See my note above on this.

 

[flyweed]

Ahhhh.....ok, that's where I was getting some confusion. Yeah my old EW300's didn't need the extra power connection.

so just so I am clear..... my FIRST UA844(head unit), I'll connect ONE RF A and ONE RF B line out, to the NEXT UA844's ANTENNA A and ANTENNA B inputs? and continue on down the line, until all 5 UA844's are connected the same way.

So for rack mounting purposes....should I mount ALL of the UA844's directly under the power strip/conditioner? Or mount them all at the bottom of the rack with the Receivers all mounted above them? Will I have issue with the power connections reaching from the UA844's to all of the receivers?

 

[mbenonis]

@flyweed Thinking about how to rack these, here is my suggestion. The note in parenthesis indicates where the input for that unit comes from. Since you have 18 units, I propose to use the Cascade Out on two of the distros to provide antenna to two receivers (this is OK to do). Power can come directly from the Head Unit, since there are five antenna outs but only four power outs. The racking scheme should give all cables enough room. Does this make sense?

And here is a modified drawing to your specific case, showing antenna signal only (not power):

 

[flyweed]

yep...that makes sense. Thanks for laying that out. I was trying to figure out what Distro to mount where to make sure both my DC power and antenna cables would reach.

 

[flyweed]

SO..head unit A is still the "master" or "main" head unit basically for signal distribution to the other 4 "head units" . so Unit A's first RF A and RF B will go up to Head Unit B. and Unit A's 2nd set of RF A and RF B ouput go to Head Unit C, and so on.

 

[macsound]

Somewhat related, what's the reason behind not daisy chaining and using this head unit idea instead?
Does the signal degrade from the loop out connection? What if you only had 8 units instead if 16. Would the level of degradation be acceptable?

 

[mbenonis]

That's exactly right, each amplifier adds noise. You want to have the fewest number of amplifiers possible in line. Whether it's acceptable or not is really dependent on the RF environment around you. You can prove this out by scanning a receiver with a whip antenna, and then scanning a receiver connected to one UA844, 2 UA844, and so on to see the increase in noise. It won't hurt it to test it like that.

 

[flyweed]

Stephan, from what I undestand from reading the info from Shure, that each "extra" connection you have to make you are losing "RF signal"

 

[flyweed]

I did find a good "rear" layout image that could help many people (like me) doing this with SHURE'S for the first time.

 

[mbenonis]

It's not so much that you lose RF signal, but that you add noise. Think of it like photocopying a document, and then photocopying the copy, etc. Or duplicating a cassette tape, then duplicating the duplicate. Each one gets worse. So that's why we want to minimize the number of amplifier stages to the receiver.

 

[macsound]

I'm not sitting in front of a rack at the moment, but isn't there another connector on the Shure antenna distribution unit? Cascade or something?
As I recall in wiring most racks I used, which usually had 2 antenna distros, the second connected through the first one somehow. Not sure if we were doing it wrong.

 

[mbenonis]

@macsound You are correct. For each of Antenna A and B, there is an input, four outputs, and a cascade port. The Cascade port is for looping to another distro. However, it can also be used to feed a fifth receiver.

The manual for the UA844+SWB is here and includes a drawing of the rear of the unit:

UA844plus SWB User Guide - Shure

The Shure UA844SWB antenna distribution system user guide.

pubs.shure.com

 

[macsound]

So is the cascade port non-filtered and non-amplified, essentially a loop through?

 

[mbenonis]

@macsound The cascade port can be treated like any of the other output ports on the unit. Think of all five outputs as equals. The naming is essentially just for clarity and to suggest an easy way to connect everything. I wouldn't read too deeply into it. Per the manual, all ports will be +/- 1 dB from input levels.

 

[Rod Reilly]

I have a simpler solution - return the 5 UA844s and buy our RFdevices ADU.24. This is a 1u dual 24way distribution amplifier that will genuinely run 24 QLXD or similar plus it has enough inbuilt power supply to run them via our custom loom. Runs about $2500 with power loom and 48 BNC-BNC cables of varying lengths (you choose). All this is to make the wiring as neat as possible. We usually mount the ADU.24 in the middle of the receivers (again among to keep cables as short as possible. I realise that this is a shameful plug and I apologize to those that I offend, but I need to let folks know this exists.