An Elegant Solution to Meeting Audio: Indoors & Outside

I never really wanted to lead anything. In fact, I spent my career trying to be the second or third in-charge. The guy one tier down the org chart who got stuff done. However, back in May of this year I was once again elected to the board of the Woodland Heights Civic Association. From 2017-2021 I was on this board as director of Communications. This time around I was elected president. I was weak and allowed myself to be talked into it.

The member’s meeting (pictured above) where the election was conducted was held outdoors in a nearby park. It was May, so the weather was nice. It wasn’t yet too hot.

The outgoing president used a small, battery operated, PA system to be able to address the gathering of  a few dozen. It looked like a tiny guitar practice amp. It had a wireless microphone with a very limited range. I suspect it was Bluetooth based. The range seemed to be about 6 feet. Take two steps away from the amp, or even turn to face away from the amp, and the signal faded. That made things a little awkward, but the business got done.

Given my background, I’m fussy about AV stuff. This experience stuck in my mind. It started me on the lookout for a better solution for meeting sound. Preferably one that was suitable for both indoor and outdoor use.

Step 1: Shure GLXD4 Wireless Microphones

I began by acquiring an inexpensive set of Shure wireless microphones. Found on EBay, these GLXD4’s are an older model. For under $100 delivered, I simply could not resist.

The microphones are SM58 Beta’s. Each takes a couple of AA batteries. The receiver is a half-rack(ish) sized, with diversity antennas. There’s an XLR out for each microphone. Also, an unbalanced TRS output that’s a mix of both microphones. It runs on 12-18 vdc.

I first used these at a later member’s meeting in August. It was held in the library of a local elementary school. So, power was readily available.

I mated them with some gear I had on-hand; a little Soundcraft Spirit Folio mixer left over from my Pixel Power days, and one of my new (and oh, so splendid!) JBL LSR705P powered monitors.

This combination worked very well indeed. It was compact, but a bit fiddly to setup. There were several power cords and audio cables involved, but it worked well, and it sounded great. It’s a way forward for WHCA member’s meetings, as long as there is power available.

That said, I really treasure the JBL 705P monitors. They are my one big audio splurge of the past decade. I would rather not haul them around. Most especially not outdoors. They don’t have built-in stand mounts. After all, they’re high-end, powered nearfield monitors, not ruggedized stage gear.

A while later we had occasion to go to dinner with some in-laws. We went to a higher-end Mexican restaurant that had a small band playing. Their PA sounded pretty good, for the size. It was from Alto Professional, a brand name I was not familiar with. So, I looked it up when I got home. This is how I stumbled upon the Alto Professional Presenter PA – Portable PA System.

Step 2: Alto Professional Presenter

This seemed to be ideal for our member’s meetings. It’s a self-contained podium with a built-in 100 Watt PA and a gooseneck microphone. It has Bluetooth connectivity allowing pairing to another source. That could be a mobile phone, computer or an additional microphone. It also has a 3.5mm TRS input for a wired AUX source.

Best of all, it’s battery operated! There’s a built-in battery charger. It can run for many hours on a charge. All-in-all, it’s a nice, self-contained package, equally suitable for use in the library at the neighboring school, or out in a park. Just plunk it down on a table, or atop a common speaker stand.

The trouble was, priced at around $400, it was more than I wanted to spend. On this occasion, I exhibited some restraint and did not order it straight away.

My restraint was ultimately rewarded, just a couple weeks later Amazon alerted me to one that was available open box for just $150! At that price, I simply could not resist.

My initial experiments with the Alto Presenter were mixed. I initially had some reservations. The proximity of the microphone to the speaker means that it can be prone to feedback as the volume is increased. That could limit it effectiveness to very small spaces/crowds. It made it easy to understand why someone might return it.

The removeable gooseneck microphone is from Rane. It appears to be part of their paging solution. It’s a super-cardioid dynamic microphone that does not require phantom power.

As as experiment, I ordered a similar gooseneck microphone made by Behringer. While it worked with the Presenter, and it had a cardioid pickup pattern, it proved to be no better. In fact, it was a little worse.

Step 3: Alto Presenter + Shure

Since I was happy enough with the Shure wireless microphones, I connected the Shure receiver to 3.5mm input on the Alto Presenter. This required only a simple 6.3mm to 3.5mm TRS adapter cable.

That combination worked well. It allows for much more volume before feedback. Also, the freedom to have one person at the podium with another microphone out in the crowd. So, I could combine the systems and/or simply not use the gooseneck microphone.

The trouble with using the Shure wireless microphone system is the requirement for power. The receiver needs 12-18 vdc. Even if just a couple of watts. That’s not so convenient for use outdoors.

At first I thought I could buy the little 120 VAC inverter that fits the 18v batteries common to the Ryobi One+ rechargeable tool set. I have several of these tools, batteries and chargers. It would surely work, but would be something more to setup and carry around. In reality, I would rarely need it, which made the expense seem unwarranted.

Then it occurred to me that the Alto Presenter has one USB-A type charging port that delivers 2.1A at 5 vdc. That’s 11 Watts. More than enough to power the Shure receiver, but it requires a minimum of 12 vdc.

DC-to-DC converters are a thing. I managed to find a USB charging cable that steps 5 vdc up to 12 vdc. This little $8 oddball cable has exactly the right 5.5 x 2.1mm coax connector for the wireless receiver.

This sort of voltage conversion cable is really elegant little solution. It’s just so simple and handy. It can be packed in with the Shure microphone kit.

To make the setup physically convenient, I used some adhesive Velcro strips to mount the Shure receiver to the side of the Presenter. So, now the entire arrangement, with three microphones, is both portable and self-powered.

We won’t actually deploy this setup for a real event for another week or so. I’m comfortable that we’ve arrived at a good solution. In simple testing in my office it works great. And I’ve not spent too much.