Author: mattwaddell

GerrAudio Demo Days 

Dec 14, 2023, 8:00 AM – Dec 15, 2023, 5:30 PM
Toronto Ontario CA

Join us at the upcoming GerrAudio Demo Days in Toronto where we will be giving demos of Sound Devices Astral® wireless audio products for the first time following the announcement that GerrAudio is now our exclusive distributor of our wireless gear for the Canadian market. 

At the Demo Days, December 13th and 14th, RF Applications Engineer Gary Trenda will have an Astral system available in the Sound Devices booth, including A20-Nexus and A20-Nexus Go multichannel true diversity wireless receivers, A20-TX and A20-Mini transmitters, PowerStation 8-M charging station, and the A20-RX receiver.  

Gary is also going to deliver a presentation at the Demo Days titled “The Advantages of Digital Wireless Technology,” where he’ll discuss the foundations of wireless operation and share stories of his work in the field where he’s faced common challenges that he’s overcome with digital audio tools. 

For more information about the GerrAudio Demo Days and to register, please visit: 

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A20-Nexus Go

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MM1:Going strong since 2002

“The MM-1 was something we were asked for quite a bit: ‘I need the MP-1, but with a headphone amp.’ This was a fairly short putt product-wise, so we did it: preamp from the MP-1 and headphone amp from the HX-3. This evergreen product is still used for many things, most often along with parabolic mics to provide a nice limiter and headphone amp for the operator. This is still manufactured today on our line in Reedsburg, WI.”

442: It’s all about outputs – 2002

“The vaunted 442 mixer was our entry into ‘the big leagues’ at the time and really put us on the map. We knew that there was a hole in the market for a full-featured, high-end 4-channel portable mixer for around $3000. Jim Koomar (Sales) and I took a trip to Minneapolis to pick [famed product designer] Peter Engh’s brain about what the product needed, and he correctly said ‘it’s all about outputs,’ meaning have many types of outputs along with the input side of things. This is where the 4 direct outs came from. This all-analog circuit is still one of my very favorite designs and near and dear to my heart. The preamps were again copied from the MP-1, complete with their Lundahl transformers and opto-isolator trim limiters. The bus limiters and mixing were done with THAT VCAs. The VCAs were trimmed on the assembly line to null the distortion using DACs and a microcontroller. Libby Koomar (Mechanical Engineer) did a superb job on the elegant mechanical design. She came up with the now-distinctive posts flanking the unit, giving it such style, which we still call ‘golf tees’ internally. We had a hard time coming up with a name, but I remember when Jon Tatooles (Marketing) came in and suggested ‘442,’ after the famous Oldsmobile muscle car. We all loved it. 4 inputs, 4 direct outs, 2 main outs.”

HX3: Made in Reedsburg Wisconsin since 2000

“The HX-3 was born out of people telling us they loved the headphone amp in the MixPre. This was for good reason, as that headphone amp features 30V of signal swing — all off of a couple of AA batteries. It is one of the many products that we make that I say are ‘sophisticated power supplies with a nice audio circuit hanging off of it.’ After shipping for a few years, this product was ripped off lock, stock, and barrel by an unscrupulous company in Taiwan, which upset me. They even copied my exact PC board layout. I’ve been asked many times: ‘Don’t your product and that other one come off of the same assembly line somewhere in Asia?’ The answer is *no*, we only make this product for Sound Devices – in Reedsburg, WI, USA, where we’re still making and selling it all these years later.”

USBPre: the world’s very first USB mic preamp – 2000

The first-generation USBPre was the very first USB microphone interface ever, from any company. I had been playing around with this new ‘USB’ computer protocol and a SPDIF-to-USB box from Opcode. It dawned on me that I could design a couple great mic preamps and supply the necessary amount of power for true 48V phantom all from the 2.5W that USB supplied if I did the power supply carefully, which was not a problem. At this point in my career, I was very strong in analog design, but less so on the digital side of things, so Jim Allard from Allard Designs did much of the work on the digital side of things. Today, there are hundreds of microcontrollers available with a USB peripheral built in, but back then the only game in town was the UDA1335 from Philips, and it left a lot to be desired but we wrapped enough parts around it to make it work for our purposes. The housekeeping was done with a venerable PIC processor. Like all of these other early products, Libby Koomar designed the mechanicals. I was very happy with the mic preamps I did in this product – all discrete, class-A, our first transformerless design. In the first couple years we shipped the USBPre, we spent a lot of time working directly with Apple and Microsoft, as both of their OSes were full of bugs in the new-to-the-world USB Audio class. Several months after shipping, we came out with a revision, USBPre-1.5, which included the much-requested SPDIF In and Out. Since this came out, there have been dozens of great (and not so great!) USB interfaces from other companies – many still bear a passing resemblance to their original predecessor.

MP-2, A Tapers Best Kept Secret – 2000

“The MP-2 was a variation of the original MixPre. We started to get word from the field that ‘tapers’ were using the MixPre for their mobile taping rigs at music concerts, and that it was missing a couple of features. As we’ve done many times since, we branched out a bit product-wise and market-wise to see what would happen – threw clay against the wall, so to speak, to see if it would stick. I put an M-S matrix into the MixPre circuitry and changed the gain pots for more precise matching. To differentiate from the similar-looking MixPre, Libby Koomar had the front panel anodized in a nice gold color, and the MP-2 was born. We picked up a couple of dealers who catered specifically to the tapers, and the MP-2 became fairly popular as a front-end to the DAT/MiniDisc/etc. recorders used at the time. Eventually, we learned more and developed our own recorders with nice inbuilt mic preamps.”