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Author Topic: Uhfr vs Ulxd  (Read 14972 times)

Diogo Nunes Pereira

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Re: Uhfr vs Ulxd
« Reply #30 on: September 28, 2016, 04:14:13 am »

The actual response is pretty ruler flat, but with some weirdness in the phase trace.

Ultimately there isn't enough gain in the beltpack to use it with a battery powered Earthworks test mic, and Shure doesn't yet make a test/measurement mic head for the handhelds.

But isn't it true that wireless mics with analog companders aren't suitable for test and measurement rigs?

Ain't all the fuss around the TM400 about this being an hybrid (compander free) transmitter? Don't really fully understand the whole hybrid concept... yet.

Companders also have me a little confused, especially the ones with variable ratio; dependent on source dynamic range. How does the receiver know which ratio the transmitter applied in the first place?

This being said, I often use my pretty flat response, omni condenser, DPA4061 lavalier as a measurement mic attached to a Shure beltpack. I don't rely on it's magnitude/phase response though. Just use it for time-alignment and delay setting of loudspeakers. Am I doing something very, very wrong? Is the impulse response also affected by the compander?

Hope I didn't raised many off-topic questions...
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Diogo Nunes Pereira
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Lee Buckalew

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Re: Uhfr vs Ulxd
« Reply #31 on: September 28, 2016, 09:30:39 am »

The actual response is pretty ruler flat, but with some weirdness in the phase trace.

Ultimately there isn't enough gain in the beltpack to use it with a battery powered Earthworks test mic, and Shure doesn't yet make a test/measurement mic head for the handhelds.

None of Shure's wireless systems are acceptable for test measurements. 

Lee
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Lee Buckalew
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Scott Helmke

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Re: Uhfr vs Ulxd
« Reply #32 on: September 28, 2016, 10:08:59 am »

ULXD doesn't use analog companding, so it's a lot closer to being usable for measurement than Shure's analog products.
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Scott Helmke

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Re: Uhfr vs Ulxd
« Reply #33 on: September 28, 2016, 10:12:43 am »

Companders also have me a little confused, especially the ones with variable ratio; dependent on source dynamic range. How does the receiver know which ratio the transmitter applied in the first place?

The transmitter can usually send small amounts of data to the receiver - battery status, etc. So it would be possible to send compander status.

ULXD does something completely different with gain setting and companding, which is how Shure was able to put the "transmitter gain" setting on the receiver.
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DavidTurner

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Re: Uhfr vs Ulxd
« Reply #34 on: September 28, 2016, 01:56:41 pm »


" 4560s with 2440s on 2350s" That was an age test Dave.  You failed  ::)

I have find memories of that set up. Please don't ruin them
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Lee Buckalew

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Re: Uhfr vs Ulxd
« Reply #35 on: October 03, 2016, 06:06:07 pm »

ULXD doesn't use analog companding, so it's a lot closer to being usable for measurement than Shure's analog products.

It is not useable for accurate test data.  Shure will tell you not to do it.

Lee
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Lee Buckalew
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Aram Piligian

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Re: Uhfr vs Ulxd
« Reply #36 on: October 04, 2016, 12:02:23 am »

For the curious, here's a comparison of the transfer function for the ULX-D pack (in red) and a direct wired connection (green). Pretty clear that it's unusable.  Excuse the crappy phone picture, I can update with a real screenshot tomorrow.
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Scott Helmke

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Re: Uhfr vs Ulxd
« Reply #37 on: October 04, 2016, 12:05:34 pm »

For the curious, here's a comparison of the transfer function for the ULX-D pack (in red) and a direct wired connection (green). Pretty clear that it's unusable.  Excuse the crappy phone picture, I can update with a real screenshot tomorrow.

It would be a desperation move, yes. That's what my trace looked like too, though mine was flatter up until it fell off a cliff around 20kHz.  Wonder how that phase trace came to be, though.
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Don Boomer

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Re: Uhfr vs Ulxd
« Reply #38 on: October 05, 2016, 11:09:09 pm »

None of Shure's wireless systems are acceptable for test measurements. 

Lee

Right. The data compression is the problem.
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Don Boomer
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Dan Currie

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Re: Uhfr vs Ulxd
« Reply #39 on: October 06, 2016, 05:05:46 am »

It would be a desperation move, yes. That's what my trace looked like too, though mine was flatter up until it fell off a cliff around 20kHz.  Wonder how that phase trace came to be, though.

The phase trace is flatter on the ulxd.  Smaart just catches the peak a little early.  In both mine and Aram's screen shot the reference signal is leading the measurement. 
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ProSoundWeb Community

Re: Uhfr vs Ulxd
« Reply #39 on: October 06, 2016, 05:05:46 am »


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