ProSoundWeb Community
Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => LAB: The Classic Live Audio Board => Topic started by: Chris Yates on April 16, 2014, 11:01:04 AM
-
We are currently looking to purchase a new microphone for our worship leader. She currently uses the Shure We have compared the Sennheiser 2000-965, Shure ULX-D, and the Shure UHF-R. Both Shures had the 87C capsule. We had issues with both Shure mics. The ULX-D had an obvious delay. We found it strange that Shure would not have a lower latency in their system. Are other people finding this latency to be unacceptable? I could not hear it while she was on stage because I could not hear any direct sound from her. As soon as she came out on the floor and I stood near her, it was obvious. She uses in IEM so the latency is definitely an issue.
The bigger problem we had was the noise generated by the UHF-R system. It caused a very distracting hum that I consider a deal breaker. We were using one channel of the UR4D Rx and a UR2 Tx with 87C capsule. I originally thought I had a problem with the channel on my console, but moving the mic to another console channel and turning the receiver off eliminated that idea. Receiver output was adjusted to try to eliminate the hum, but it didn't help. Has anybody else experienced this issue with UHF-R system cause a lot of noise?
At this point, my preference is the Sennheiser, but I figured I would solicit feedback here before we rule anything out. Our worship leader isn't particularly fond of the warmer sound of the Sennheiser and tends to perfer the crispness of the Shures.
-
We found it strange that Shure would not have a lower latency in their system. Are other people finding this latency to be unacceptable? I could not hear it while she was on stage because I could not hear any direct sound from her. As soon as she came out on the floor and I stood near her, it was obvious.
The bigger problem we had was the noise generated by the UHF-R system. It caused a very distracting hum that I consider a deal breaker.
When she came out on the floor and you stood near her, she was closer to you than the main speakers, so the time of flight from the mains would be the difference you heard (about one millisecond per foot), not the short latency of the UHF-R RF system, which has similar latency to other RF systems of that era.
A "very distracting hum" is probably a ground loop, which is a sound system problem, not specific to the UHF-R. Try a pin one lift.
-
My church uses a Shure UHF-R rig. No hum for me, try the ground lift as Art has suggested, either that or you have a bad unit. IMO I prefer the SM86 to the Beta variant, less harshness, but I guess it all depends on the voice and technique.
-
When she came out on the floor and you stood near her, she was closer to you than the main speakers, so the time of flight from the mains would be the difference you heard (about one millisecond per foot), not the short latency of the UHF-R RF system, which has similar latency to other RF systems of that era.
A "very distracting hum" is probably a ground loop, which is a sound system problem, not specific to the UHF-R. Try a pin one lift.
Normally, I would agree with this, but the latency was only heard with the ULX-D. We could not hear any perceivable delay with the UHF-R.
In regards to the hum, a ground loop could make sense because I plugged the receiver into a general power circuit, not an audio circuit. However, the ULX-D was plugged into this same general power circuit and did not have the humming problem. The ULX-D uses a transformer so maybe that could eliminate any ground loop issue with the ULX-D.
My church uses a Shure UHF-R rig. No hum for me, try the ground lift as Art has suggested, either that or you have a bad unit. IMO I prefer the SM86 to the Beta variant, less harshness, but I guess it all depends on the voice and technique.
Good to know about the SM86. One of the things I didn't like about the Shures was how harsh they sounded. I may have an SM86 on a different mic in the building that I can try out.
-
Normally, I would agree with this, but the latency was only heard with the ULX-D. We could not hear any perceivable delay with the UHF-R.
The latency of the ULX-D is 2.9ms. It is unlikely that you would have noticed that latency on its own. Combined with the latency of other downstream systems it may be greater. A useful test may be to use a wired mic and add delay in fraction of a millisecond steps till it becomes obvious and/or objectionable. This will give you a guideline on how much additional latency over any fixed system latency you can tolerate.
Mac
-
Normally, I would agree with this, but the latency was only heard with the ULX-D. We could not hear any perceivable delay with the UHF-R.
In regards to the hum, a ground loop could make sense because I plugged the receiver into a general power circuit, not an audio circuit. However, the ULX-D was plugged into this same general power circuit and did not have the humming problem. The ULX-D uses a transformer so maybe that could eliminate any ground loop issue with the ULX-D.
I'd be quite impressed if you could actually hear a 2.9ms delay. That is equivalent to a distance of about 3 feet away. You said you heard the delay when she came out off the stage and stood next to you. The delay from the distance from the main speakers is going to be far greater than that introduced by the wireless mic.
Humming problems in audio are quite common, even with the best of gear. Knowing how to troubleshoot and fix them is pretty important. A simple isolation transformer often is all that is needed to break a ground loop. I wouldn't write off the UHF-R so quickly. However, everything I have read and heard tells me the ULX-D blows away the UHF-R system for a fraction of the price.
-
AKG DMS700 is 3.5ms on latency.
Another question is are you using the encryption? This may add time to the latency? Not shure on this and untested. Yes pun intended.
-
The latency with the ULX-D should be on the order of <3ms. You would not perceive this as a discrete delay and probably would only notice the comb filtering if you were the singer and using IEMs. I suspect there is something else creating this delay.
The hum issue is a ground loop and has nothing to do directly with the ULX-D.