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LMA vs um400a

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I've found a little bit of talk, but not much. I have been entertaining the idea of getting some LMA tx's as they are quite a bit cheaper than the um400's but was wondering what some users experience's have been that have used both. I'm aware of the power difference, but Zax also uses 50 mW in most of their tx's. What have your experiences been?

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New price list being type set.

LarryF

I've always resisted commenting on the lma because I'm afraid Lectro is going to wise up and start charging more for them. But I've knocked back a couple, which is always ill-advised when posting, but I'll probably delete this in the morning anyway.

The lma's lower power is virtually indistinguishable from a um400a, 100mw transmitter. While visiting with the bunch of hams (I'm KQ5I) who volunteered to check freq's at the last superbowl, we did comparisons and measurements with their very expensive spectrum analyzers, and found the lma has to have at least 70+ mw of power, and in real world situations, the difference between the two matters little. Audio-wise, they are identical, both in specification and in the real world. The fixed antenna on the lma is an advantage, as it is more robust than the connector affair, and makes the antenna physically shorter by eliminating the connector. The spring clip has a lower profile than the clunky um400a clip, and the "lip" can be bent down to make the profile even lower. Excellent in a bra-strap mount, where I go 90% of the time. Less excellent on the waistband, tends to fall off, but considering the lma's low-profile without clip, pouch-wise and concealment-wise, it runs a close second to the SM's and their ilk. Hides well in the men's front pants pocket, I defy you to see it on camera. The clip pops on and off in a second, no tools required. The power switch seems different than the um's, and is mounted differently, but I can shut it off and adjust gain by feel thru most materials on a women's back. (somehow my jobs are mostly women on camera). Finally, when monkeying with 10 wireless going at once, I'll take lower power over higher. There, I've said enough already. Larry please don't raise the price on the Lma's...

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I'm looking at buying a couple of extra wireless kits to use as a camera hop but also as spare talent radio mics. I'm going to get an SRa receiver but I'm not too sure about which transmitters to pair it with. The LMa seems like good value for money but maybe I could have some inter-modulation issues using them close together in a bag. I'm basing this on this comment which I read on dvxuser:

"The LMa (replacement for the older LM) does actually have the circular isolator now, so this greatly reduces the level of any intermod products. So essentially, the LMa is now a lower power version of the UM400a.

But I wanted to clarify this issue of isolator vs. no isolator and the potential for intermod interference. First off, transmitters have to be VERY close together to show appreciable intermod levels. Even then, transmitters with robust output designs (RF amps with headroom) exhibit lower intermods than comparable transmitters with less robust designs. We've done testing here that shows that the original LM (~50mW) shows much lower intermod levels than comparable 30mW transmitters. So in practice, this is almost moot. There are quite a few multi-channel setups out there with original LM transmitters and they work great."

As it says above, they have to very close together to show intermod levels, which they would be in a bag as a hop. Anyone got other tips on reasons not to get an LMa as a hop/backup talent mics? Any other comments about the LMa vs UM400a?

Thanks all.

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I have some LM and LMa that I bought when transitioning from Sennheiser G2s, and still use them when needing a lot of transmitters. We used them yesterday in fact. The LMa and 401 RX is a relatively inexpensive way to get Lectrosonics. Not all the glory of the 411 and UM400 (or SMQV), but leap and bounds ahead of a Sennheiser G2 or Micron.

There is an old thread here or on RAMPS about the differences, though it may have been when this was still JWSound.org and I don't know if all those old threads survived the move.

Off the top of my head, the LM/LMa is rated at 50mw versus 100, though in reality they are often up to 70mw. In the real world that means they are darn close in effective output (and range). The LMa has a fixed antenna. Might not matter for you. I never ruined an antenna, though there were times I have improved transmission with my SMQVs by putting out a remote antenna (for something like a car or boat rig). The LMa has a fixed low end roll off compared to the UM. The lower power also means they get great battery life with iPower rechargeables or alkalines.

In my bag work I am often much closer to camera than I can count on talent being to me. The wireless hop is more convenience/safety than a long distance hop. That would make the LMa a great wireless hop kit, that can get repurposed as body packs. They are also commonly used for bag IFB transmitters.

Personally, I would buy a LMa over a UM400, though my first choice is the SMQV or SMV (until the WM ships).

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All UHF Lectro transmitters have isolators.

LarryF

Lectro

I'm looking at buying a couple of extra wireless kits to use as a camera hop but also as spare talent radio mics. I'm going to get an SRa receiver but I'm not too sure about which transmitters to pair it with. The LMa seems like good value for money but maybe I could have some inter-modulation issues using them close together in a bag. I'm basing this on this comment which I read on dvxuser:

"The LMa (replacement for the older LM) does actually have the circular isolator now, so this greatly reduces the level of any intermod products. So essentially, the LMa is now a lower power version of the UM400a.

But I wanted to clarify this issue of isolator vs. no isolator and the potential for intermod interference. First off, transmitters have to be VERY close together to show appreciable intermod levels. Even then, transmitters with robust output designs (RF amps with headroom) exhibit lower intermods than comparable transmitters with less robust designs. We've done testing here that shows that the original LM (~50mW) shows much lower intermod levels than comparable 30mW transmitters. So in practice, this is almost moot. There are quite a few multi-channel setups out there with original LM transmitters and they work great."

As it says above, they have to very close together to show intermod levels, which they would be in a bag as a hop. Anyone got other tips on reasons not to get an LMa as a hop/backup talent mics? Any other comments about the LMa vs UM400a?

Thanks all.

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I use two LMas for camera hop in a bag sitting right next to each other, touching, in fact, w/o issues. Great low-cost high quality gear. I've also used them on talent and didn't have any diff in real world performance re: my 400/411s, that I could tell on the fly.

phil p

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I use two LMas for camera hop in a bag sitting right next to each other, touching, in fact, w/o issues.

phil p

+1 for LMa. The best price/performance piece of gear I have ever owned. Philip did you drill the doors for battery Eliminators? I did and am very happy that don't have to monitor batteries. P-Did if you use more then one LMa make sure they are coordinated.

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+1 for LMa. The best price/performance piece of gear I have ever owned. Philip did you drill the doors for battery Eliminators? I did and am very happy that don't have to monitor batteries. P-Did if you use more then one LMa make sure they are coordinated.

Indeed, coordinating is key especially when I'm using 6-7 wireless. The FreqFinder app has been amazing for that.

My LMa's have been rock solid. Hard to tell a difference if any, in performance, from my UM400a's.

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Indeed, coordinating is key especially when I'm using 6-7 wireless. The FreqFinder app has been amazing for that.

My LMa's have been rock solid. Hard to tell a difference if any, in performance, from my UM400a's.

I meant it is especially important for the LMa. As a general rule I always coordinate.

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I meant it is especially important for the LMa. As a general rule I always coordinate.

What makes the lma any different from any other tx when it comes to the necessity for freq. coordination?

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Nothing at all.

Best,

Larry F

Lectro

What makes the lma any different from any other tx when it comes to the necessity for freq. coordination?

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Side question: is frequency coordination (by that I mean doing more than just spacing the frequencies apart far enough) necessary when using only two transmitters in one block or does it only make sense when you have a large number of transmitters in one block?

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Side question: is frequency coordination (by that I mean doing more than just spacing the frequencies apart far enough) necessary when using only two transmitters in one block or does it only make sense when you have a large number of transmitters in one block?

Two transmitters can cause intermod products that could interfere with only a third receiver, assuming the first two receivers are tuned to the transmitters themselves. If you only have two receivers and transmitters, intermod will not be a problem. The block separation question depends on the type receiver and its front end. Block 21 and 23, for instance, will have enough separation that receiver intermod should not be a problem with only two transmitters in a block, even more so with the tracking front end units.

Best Regards,

Larry Fisher

Lectrosonics

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