Wireless mics - your opinion please

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Proformance

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Nov 6, 2006
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I’ve been there way back with blx mics and it didn’t work at all I had to go to a wired mic
There's nothing inherently wrong with BLX or even PGX mics. They work fine if deployed properly, there's just not a lot of versatility or control available if you are trying to navigate very complex RF situations. The design assumption is that users are unlikely to be using more than 2 these systems at a time, and they will be indoors at relatively close range.

To get a dozen or more of this mic class to work simultaneously requires some serious RF planning and care. One of the most common areas for this problem is school and community theater. Here, the budgets are low but the number of people wearing a mic and the subsequent expectations are high. A parallel situation occurs when there a multiple DJs working within a multi-room event space like large hotels or conference centers. DJs tend to buy similar modest level gear which is also consistent with gear used by restaurants/bars and other hospitality services. The odds of multiple entertainers and hospitality workers stepping on each others RF increases quickly in busy commercial areas.
 
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djtaso

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There's nothing inherently wrong with BLX or even PGX mics. They work fine if deployed properly, there's just not a lot of versatility or control available if you are trying to navigate very complex RF situations. The design assumption is that users are unlikely to be using more than 2 these systems at a time, and they will be indoors at relatively close range.

To get a dozen or more of this mic class to work simultaneously requires some serious RF planning and care. One of the most common areas for this problem is school and community theater. Here, the budgets are low but the number of people wearing a mic and the subsequent expectations are high. A parallel situation occurs when there a multiple DJs working within a multi-room event space like large hotels or conference centers. DJs tend to buy similar modest level gear which is also consistent with gear used by restaurants/bars and other hospitality services. The odds of multiple entertainers and hospitality workers stepping on each others RF increases quickly in busy commercial areas.
They serve their purpose... but location and environment as always play a role. Both times I used them were indoors... one was in south jersey by the delaware river near a port, where I couldn't go more than 10ft without losing signal. Never happened to me in my life where it was that bad. No other event, no other microphones, tried multiple channels. Nothing. I'm not the only one. Since then, the venue has installed a professional grade mic system that covers the entire reception room. Just had another dj complain on a local forum with that type of mic in jersey city... constant drop outs. In NJ most top djs use the qlx systems.
 
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MIXMASTERMACHOM

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I used my Shure BLX 288 system yesterday and no issues. Other times I have had issues. I will keep using it as I don't have the money to upgrade like others have suggested.
 

azdeejay

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Yup. Everything above 608 MHz is now pretty much all used for 5G and it is illegal to operate mics in that band except for a small 6 MHz sliver in the duplex gap (657-663 MHz if memory serves me well). 5G will keep proliferating so you are best to get rid of those mics as soon as possible.
Funny enough, the GTD set I have can be set to operate in that range I believe, but I want to upgrade mics to get out of the 600 range and smaller receiver boxes.
 
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rickryan.com

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Funny enough, the GTD set I have can be set to operate in that range I believe, but I want to upgrade mics to get out of the 600 range and smaller receiver boxes.
I really like (love) this new Sennheiser lav but I'm probably going to order a newer GTD lav/mic combo (outside the offending frequencies), just to have a backup.
 

BlueLineDJ

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Update: My trusty old GTD finally died last week. I was going to order a Shure system but there are none to be found anywhere. I'm headed down to Guitar Center tomorrow where they'll hopefully still have a Sennheiser XSW2 in stock.
I was told that there are Shure orders that were placed in May 2021 that won't be filled until June 2023.
 

Proformance

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Just to be clear, using a 600 MHz mic is not "illegal" it's unauthorized . .which is an important legal distinction.

The FCC is a regulatory agency not a branch of law enforcement.
 
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Proformance

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They serve their purpose... but location and environment as always play a role. Both times I used them were indoors... one was in south jersey by the delaware river near a port, where I couldn't go more than 10ft without losing signal. Never happened to me in my life where it was that bad. No other event, no other microphones, tried multiple channels. Nothing. I'm not the only one. Since then, the venue has installed a professional grade mic system that covers the entire reception room. Just had another dj complain on a local forum with that type of mic in jersey city... constant drop outs. In NJ most top djs use the qlx systems.
That's a Frequency BAND issue not a mic problem. If a person doesn't verify the proper band of PGX or BLX product PRIOR TO PURCHASE the issues they encounter are user error rather than a product fault.

QLXD and ALL OTHER MICS have to operate in the same available spectrum and the key to selecting the right product lies in a review of the local spectrum before you select which product to use.

Anyone who travels from one town to another will need to own multiple wireless products in different bands to accommodate the varying conditions of each location they intend to work. "South Jersey" for example, is not useful delineation of RF space upon which to select a microphone. At this stage of technology you may at best need the name of the exact town you are in, and at worse, the specific street address.


Example 1:
There are no reliable frequencies in my hometown for which I can use an SLX H5 system. But there are a dozen towns within just 8 miles (15 minutes) of my address where I would have up to 12 available frequencies in which to operate a quad set of those same mics. Hence, what you think about the performance of that product will change dramatically from one location versus another if the discreet RF space is not being accounted for.

I resolve issues like this by stocking different types of mic systems across a variety of bands so that I can deploy the best product for THAT LOCATION. For a disc jockey, I think for many the days are gone where you can simply own one microphone and expect it to work everywhere you go. For others in more remote areas that window is closing and more frequent issues will start to appear.
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Example: 2
I recently resolved an issue with a school district theater production. They were using 3 QLXD (digital), 2 PGXD (digital), 4 BLX (analog) and 6 PGX (analog) microphones simultaneously across the X9, H8, H6, H10, and L50A bands.

They believed the problems to be intermittent issues with their $29 Amazon headset mics when in reality, it was the lack of RF planning or understanding. All of these mics were stepping on each other in a variety of ways, none of which were a case of direct interference from two mics operating on the same frequency.

The reality of complex RF environments is the way products and signals might interact with one another and not simply whether a given channel is "clear." In the end, I was able to give them 15 working frequencies and another 4 backup frequencies - but, that was all. There was no other way to get that group of products to function together in the same operational field of influence.
 
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Proformance

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Here's an over-simplified or exaggerated example of inter modulation and other RF spikes that can occur when using multiple mics on otherwise independently clear channels. While this example kind of cheats (it's not a pure example) it does provide a very visual representation of things that can be going on with our own equipment that we can't easily see or detect. The issues we experience with wireless mics can often be self-created. It's not necessary to be in a crowded RF environment to experience serious reception issues.

If you look at the first photo you see 2 transmitters, and their associated receivers with a clear indication of RF lock on the display (amber LED column).
You'll notice that a 3rd receiver (lower right) also shows a (slightly lower) yet solid RF signal despite no active transmitter on that channel.

DSC02817.JPG

That 3rd receiver is subject to a very strong RF signal on a DIFFERENT frequency that is a product of the two transmitters being so close together in tight proximity with the receiving antennas.

If we turn either of the transmitters off (2nd & 3rd photos) that 3rd RF spike goes away. It doesn't matter which one is still on - the new frequency spikes only appear when more than one mic is in use. These spikes are a mathematical series resulting from the nature and interaction of the channels in use.

DSC02819.JPG _ DSC02820.JPG

If we turn both mics back on and move them further away from the receiving antennas (> 4Ft) we can see in the 4th photo that a third RF spike no longer registers on the RF meter and both mics appear to have a solid RF lock. This condition varies if the mics are in motion - again in relation to their proximity with each other, and the receivers.

DSC02818.JPG

It's important to know that the spike is still there even though it's intensity has been reduced below what the receiver's display might indicate. There is still a possibility that it may cause drop outs or interference when any or all of these transmitters are in use.
 
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MIXMASTERMACHOM

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Let me add this. It is suggested to get a unit that has antennas on the outside. The BLX system has built in antennas.
 

Proformance

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Let me add this. It is suggested to get a unit that has antennas on the outside. The BLX system has built in antennas.
The BLX line is available in a rack mount chassis for use with external antennas or system integration. The performance of the system doesn't change It simply allows you other installation options - for example, a church where the equipment rack/receivers are in a different room.

I have not had issues using BLX mics in venues where I find them, including the portable models with internal antennas. There's a dual version in a local theater I work with where the receiver is in the rear FOH booth and the mics are over 100Ft away on stage. No problem.
 
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Proformance

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I used my Shure BLX 288 system yesterday and no issues. Other times I have had issues.
Before you take this mic to a gig:

Use the FREE online utility: "Shure Wireless Frequency Finder" to obtain the best recommended Group and Channel to use for the exact location at which you intend to use the BLX mics. It may be different for each location, even if the sites are just several blocks apart.

Shure also has a free software utility (Wireless Workbench) that can manage your entire mic inventory including products by other manufacturers, as well as other non-audio RF devices.

This is not a complete solution - but it takes into account all known sources of RF such as TV, Radio, Commercial, and Civil Defense/Safety communication systems in the area you intend to work. That's a big chunk of potential issues that can be solved before we even leave home.

Each of my mic kits also contain "cheat sheets" with this recommended information already printed out for many of the localities I frequently work. They provide a quick reference should I forget to do this homework in advance and have no internet access on site.

The last ditch solution is a portable RF Spectrum analyzer, but I don't often carry this with me. I generally use it as a problem solving tool on tech calls.
 
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