I just purchased (4) ULX-D sight unseen due to an immediate need to replace the ULX-Pro's that I just sold. As a result, I have no track record to report on, only short term observations and measurements. Subjective impressions are voice only at this point with handhelds using Beta 87A capsules. The sound is very neutral with very low noise. Comparisons to a mic cable are reasonable with voice.
Conclusion:
The sales pitch behind these things might lead one to think they'll sound better than the UHF-R. Digital is always better, right? Lectrosonics developed the hybrid analog/digital systems because they couldn't figure out how to make a pure digital system, right? Shure was just asleep when they redesigned the UHF-R series into the Axient, right? No, no and no.
Nevertheless the ULX-D is an improvement on the ULX-Pro in sound, build quality, feature set, rider acceptance and is still dead simple to operate. Pricing has increased by about 63%, which is modest for the improvements made and represents a very good deal IMO.*
On the feature set, the encryption is interesting and may prove helpful some day, though I've yet to have the need for it. The ground breaking feature that will result in many users experiencing a low noise floor for the first time with their wireless use is the automatic gain compensation in the transmitters. It's amazing that as much emphasis as people put on getting their gain structures in the ball park with copper circuits, they often ignore the even greater need to do so with their wireless systems. Shure is going to allow them to remain ignorant with the ULX-D and allow the rest of us one less thing to deal with when changing handheld capsules, beltpack attachments, and/or source volumes. Well done Shure.
I was initially interested in the Lectrosonics Venue system, but they don't seem to have an adapter for their beltpack to accept Shure pinouts. I have over 10 grand (dealer cost) in headworns and the like. Lectro needs to design and sell a 0.5" long adapter that will do this. Please. I'll look again when my UHF-R units need replacement.
Measurements and Comments:
I've more or less repeated the measurement scheme I used in a prior review for sake of comparison.
Shure ULX-D:
System setup: transmitter 12dB pad off, receiver output switched to line level, software controlled output gain set to +3dB. If the pad were engaged, all the following levels could be increased by 12dB. Pink noise stimulus was not required due to the lack of companding.
The beltpack's input clips at +12dBu with a 1kHz continuous sine. This is accurately indicated on both BP and receiver's LCD screens with a full screen flashing "OVERLOAD". We know where they stole that idea from and it's about time.
The red LED on the receiver indicates limiting regardless of what the manual might lead you to believe. Limiting begins 18dB prior to clipping, or -6dBu in this case. THD is about .01% up to -7dBu and rises to about .03% from -6dBu to +11dBu. Additional signal input beyond -6dBu is not reflected in the output due to the limiter.
In summary, the receivers' red LED's indicate low distortion hard limiting, a flashing "OVERLOAD" on either transmitter or receiver LCD screens means what it says.
The maximum line level output of the receiver is 20.7dBu which is achieved with a -6dBu input.
Interestingly, latency is slightly less than the 2.90ms specification at 2.73ms, but the price that was paid to achieve this puts the system out of the running for sources with frequency content above the vocal region IMO.
The first two channel transfer function measurement was made with a swept sine starting at -50dBu and increased in steps of 10dB through -20dBu, then a final measurement at -18dBu as that was the maximum possible prior to the onset of limiting with this stimulus type. The second measurement displays the impulse response responsible for that phase behavior. The measurements display magnitude traces 6dB lower than actual due to unbalanced drive of beltpack vs. the internally balanced loopback used in CLIO. UHF-R measurements are included for comparison though you might want to read the post referenced to earlier for more on these high-end systems.
ULX-D Transfer Function with Phase:
ULX-D Transfer Function with IR at -18dBu:
UHF-R Transfer Function with Phase:
UHF-R Transfer Function with IR at -18dBu:
Shure's designers appear to hail from the classic school of magnitude. The phase response of the ULX-D is flat just through the vocal range, though is worse than the original analog ULX or any other wireless system I'm aware of above that. It's my guess that Shure did this as a way of reducing latency. This phase error is likely to be audible with a very good PA with acoustic guitar and other instruments with significant HF content. Still, for a wireless system that will most often be used with handhelds or beltpacks with headworn mics, this seems like a reasonable engineering compromise. You can forget using the ULX-D for wireless measurement.
Given the lack of companding shown in the swept sine tests and the extended LF response, this system should prove to be excellent for LF instruments such as bass guitar. The following 15ms tone burst measurements indicate that an extremely dynamic source like this should be reproduced accurately. The maximum RMS of the instrument should be held 12dB below limiting (the red LED on the receiver). This corresponds with the illumination of the first yellow LED on the receiver. The metering is like the UHF-R and PSM900 in that it displays both RMS and peak levels with the latter bouncing around on a single LED. It is the lower contiguous string of illuminated LED's that need to be held to the first yellow LED or lower. There is a good chance that the beltpack will need it's 12dB pad engaged to achieve this.
Blue and red traces resulted from a -18dBu drive level, pink and cyan traces resulted from a drive level 24dB higher than that, which is the maximum the beltpack can accept before objectionable distortion with this type of stimulus with the pad off.
Gated Sine Burst with THD:
Second Witch:
"Eye of newt, and toe of frog,
Wool of bat, and tongue of dog,
Adder's fork, and blind-worm's sting,
Lizard's leg, and howlet's wing,
Wireless mics we too shall bring,
For a charm of powerful trouble,
Like a hell-broth boil and bubble."
Shakespeare's Macbeth (IV, i, 14-15), for the most part.
* Edit: I originally stated that the pricing was about the same as the old ULX-Pro. I went on memory which is unwise given the fact that I haven't had an upgrade since birth even though I'm processing much more information.
Conclusion:
The sales pitch behind these things might lead one to think they'll sound better than the UHF-R. Digital is always better, right? Lectrosonics developed the hybrid analog/digital systems because they couldn't figure out how to make a pure digital system, right? Shure was just asleep when they redesigned the UHF-R series into the Axient, right? No, no and no.
Nevertheless the ULX-D is an improvement on the ULX-Pro in sound, build quality, feature set, rider acceptance and is still dead simple to operate. Pricing has increased by about 63%, which is modest for the improvements made and represents a very good deal IMO.*
On the feature set, the encryption is interesting and may prove helpful some day, though I've yet to have the need for it. The ground breaking feature that will result in many users experiencing a low noise floor for the first time with their wireless use is the automatic gain compensation in the transmitters. It's amazing that as much emphasis as people put on getting their gain structures in the ball park with copper circuits, they often ignore the even greater need to do so with their wireless systems. Shure is going to allow them to remain ignorant with the ULX-D and allow the rest of us one less thing to deal with when changing handheld capsules, beltpack attachments, and/or source volumes. Well done Shure.
I was initially interested in the Lectrosonics Venue system, but they don't seem to have an adapter for their beltpack to accept Shure pinouts. I have over 10 grand (dealer cost) in headworns and the like. Lectro needs to design and sell a 0.5" long adapter that will do this. Please. I'll look again when my UHF-R units need replacement.
Measurements and Comments:
I've more or less repeated the measurement scheme I used in a prior review for sake of comparison.
Shure ULX-D:
System setup: transmitter 12dB pad off, receiver output switched to line level, software controlled output gain set to +3dB. If the pad were engaged, all the following levels could be increased by 12dB. Pink noise stimulus was not required due to the lack of companding.
The beltpack's input clips at +12dBu with a 1kHz continuous sine. This is accurately indicated on both BP and receiver's LCD screens with a full screen flashing "OVERLOAD". We know where they stole that idea from and it's about time.
The red LED on the receiver indicates limiting regardless of what the manual might lead you to believe. Limiting begins 18dB prior to clipping, or -6dBu in this case. THD is about .01% up to -7dBu and rises to about .03% from -6dBu to +11dBu. Additional signal input beyond -6dBu is not reflected in the output due to the limiter.In summary, the receivers' red LED's indicate low distortion hard limiting, a flashing "OVERLOAD" on either transmitter or receiver LCD screens means what it says.
The maximum line level output of the receiver is 20.7dBu which is achieved with a -6dBu input.
Interestingly, latency is slightly less than the 2.90ms specification at 2.73ms, but the price that was paid to achieve this puts the system out of the running for sources with frequency content above the vocal region IMO.
The first two channel transfer function measurement was made with a swept sine starting at -50dBu and increased in steps of 10dB through -20dBu, then a final measurement at -18dBu as that was the maximum possible prior to the onset of limiting with this stimulus type. The second measurement displays the impulse response responsible for that phase behavior. The measurements display magnitude traces 6dB lower than actual due to unbalanced drive of beltpack vs. the internally balanced loopback used in CLIO. UHF-R measurements are included for comparison though you might want to read the post referenced to earlier for more on these high-end systems.
ULX-D Transfer Function with Phase:
ULX-D Transfer Function with IR at -18dBu:
UHF-R Transfer Function with Phase:
UHF-R Transfer Function with IR at -18dBu:
Shure's designers appear to hail from the classic school of magnitude. The phase response of the ULX-D is flat just through the vocal range, though is worse than the original analog ULX or any other wireless system I'm aware of above that. It's my guess that Shure did this as a way of reducing latency. This phase error is likely to be audible with a very good PA with acoustic guitar and other instruments with significant HF content. Still, for a wireless system that will most often be used with handhelds or beltpacks with headworn mics, this seems like a reasonable engineering compromise. You can forget using the ULX-D for wireless measurement.
Given the lack of companding shown in the swept sine tests and the extended LF response, this system should prove to be excellent for LF instruments such as bass guitar. The following 15ms tone burst measurements indicate that an extremely dynamic source like this should be reproduced accurately. The maximum RMS of the instrument should be held 12dB below limiting (the red LED on the receiver). This corresponds with the illumination of the first yellow LED on the receiver. The metering is like the UHF-R and PSM900 in that it displays both RMS and peak levels with the latter bouncing around on a single LED. It is the lower contiguous string of illuminated LED's that need to be held to the first yellow LED or lower. There is a good chance that the beltpack will need it's 12dB pad engaged to achieve this.
Blue and red traces resulted from a -18dBu drive level, pink and cyan traces resulted from a drive level 24dB higher than that, which is the maximum the beltpack can accept before objectionable distortion with this type of stimulus with the pad off.
Gated Sine Burst with THD:
Second Witch:
"Eye of newt, and toe of frog,
Wool of bat, and tongue of dog,
Adder's fork, and blind-worm's sting,
Lizard's leg, and howlet's wing,
Wireless mics we too shall bring,
For a charm of powerful trouble,
Like a hell-broth boil and bubble."
Shakespeare's Macbeth (IV, i, 14-15), for the most part.
* Edit: I originally stated that the pricing was about the same as the old ULX-Pro. I went on memory which is unwise given the fact that I haven't had an upgrade since birth even though I'm processing much more information.
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