Category Archives: Gear for Sound and Lighting

Reviews and opinions regarding audio and lighting equipment.

Comparisons Of Some Powered Loudspeakers

Let’s measure some boxes!

Please Remember:

The opinions expressed are mine only. These opinions do not necessarily reflect anybody else’s opinions. I do not own, operate, manage, or represent any band, venue, or company that I talk about, unless explicitly noted.

Want to use this image for something else? Great! Click it for the link to a high-res or resolution-independent version.

Over time, I’ve become more and more interested in how different products compare to each other in an objective sense. This is one reason why I put together the The Great, Quantitative, Live-Mic Shootout. What I’m especially intrigued about right now is loudspeakers – especially those that come packaged with their own internal amplification and DSP. Being able to quantify value for money in regards to these units seems like a nifty exercise, especially as there seems to be a significant amount of performance available at relatively low cost.

Over time, I’ve used a variety of powered loudspeakers in my work, and I have on hand a few different models. That’s why I tested what I tested – they were conveniently within reach!

Testing Notes

1) The measurement mic and loudspeaker under test were set up to mimic a situation where the listener was using the loudspeaker as a stage monitor.

2) A 1-second, looping, logarithmic sweep was used to determine the drive level where the loudspeaker’s electronics reached maximum output (meaning that a peak/ limit/ clip indicator clearly illuminated for roughly half a second).

3) Measurements underwent 1/6th octave smoothing for the sake of readability.

4) These comparisons are mostly concerned with a “music-critical band,” which I define as the range from 75 Hz to 10,000 Hz. This definition is based on the idea that the information required for both creating music live and enjoying reproduced sound is mostly contained within that passband.

5) “Volume” is the number of cubic inches contained within a rectangular prism just large enough to enclose the loudspeaker. (In other words, how big of a box just fits around the loudspeaker.)

6) “Flatness Deviation” is the difference in SPL between the lowest recorded level and highest recorded level in the music-critical band. A lower flatness deviation number indicates greater accuracy.

6) Similarly to #5, “Phase Flatness Deviation” is the difference between the highest phase and lowest phase degrees recorded in the music-critical band. (The phase trace is a generated, minimum-phase graph).

8) Distortion is the measured THD % at 1 kHz.

9) When available, in-box processing was set to be as minimal as possible (i.e., flat EQ).

Test Results And Comments (In Order Of Price)

Alto TS312

Acquisition Cost: $299
Volume: 4565 in^3
Mass: 36 lbs
Magnitude And Phase:
Flatness Deviation: 12 dB
Phase Flatness Deviation: 166 degrees
Peak SPL: 119.6 dB
Distortion @ 1 kHz: 1.1%
Comments: Good bang vs. buck ratio. Highly compact, competitive weight. Surprisingly decent performer, with respectable output and distortion characteristics. Lacks the “super-tuned” flatness of a Yamaha DBR, and not as clean as the JBL Eon. Simplified back panel lacks features, but also is hard to set incorrectly. Would have liked a “thru” option, but the push-button ability to lift signal ground is nice to have.

Peavey PVXP12

Acquisition Cost: $399
Volume: 5917 in^3
Mass: 43 lbs
Magnitude And Phase:
Flatness Deviation: 14 dB
Phase Flatness Deviation: 230 degrees
Peak SPL: 123.8 dB
Distortion @ 1 kHz: 1.61%
Comments: High output at limit, but the manufacturer allows for rather more distortion compared to other products. Not factory-tuned quite as flat as other boxes, with an output peak that reads well as a “single number” performance metric…but also sits in a frequency range that tends to be irritating at high volume and troublesome for feedback. The enclosure is hefty and bulky in comparison to similar offerings.

JBL Eon 612

Acquisition Cost: $449
Volume: 4970 in^3
Mass: 33 lbs
Magnitude And Phase:
Flatness Deviation: 11 dB
Phase Flatness Deviation: 145 degrees
Peak SPL: 114.3 dB
Distortion @ 1 kHz: 0.596%
Comments: Relatively low output, but also tuned to a more more flat solution than some (and with rather lower distortion). Has some compactness and weight advantages. Lots of digital bells and whistles, but the utility of the features varies widely across different user needs. (For instance, I would prefer trading more power and an even flatter tuning for the Bluetooth control connectivity.) Not particularly enamored of the “boot-up” time required for all the electronics to register as ready for operation.

Yamaha DBR 12

Acquisition Cost: $499
Volume: 4805 in^3
Mass: 34.8 lbs
Magnitude And Phase:
Flatness Deviation: 10.6 dB
Phase Flatness Deviation: 180 degrees
Peak SPL: 119.5 dB
Distortion @ 1 kHz: 0.606%
Comments: Good output at low distortion. Compact box in comparison to others. Competitive in terms of weight. Slightly more expensive than other offerings, commensurate with its improved performance. Measures very well in the “intelligibility zone” of its frequency response. Very pleased with the simple and robust selector switches for most operations.


The POTH Commentaries – VCAs/DCAs

VCA/ DCA control is very handy, especially for “non-homogenous” routing situations.

Please Remember:

The opinions expressed are mine only. These opinions do not necessarily reflect anybody else’s opinions. I do not own, operate, manage, or represent any band, venue, or company that I talk about, unless explicitly noted.

Want to use this image for something else? Great! Click it for the link to a high-res or resolution-independent version.

Author’s Note: This article is the first in a short series that addresses concepts and happenings related to Pigs Over The Horizon, a Pink Floyd tribute starring Advent Horizon and Friends.


When you start working with more full-featured consoles, you’ll likely run across something you might not have seen before. It’s a control feature called the VCA, or sometimes DCA on digital desks. What is this strange creature? What is it good for?

First off: A VCA is a Voltage Controlled Amplifier. The “D” comes in as a way to say that the same concept is being applied in the digital realm. (In my opinion, a digital system has it much easier, because you don’t have to work with analog circuit logic and the complexities of components or circuit layouts that come with that whole business.) The whole notion rests squarely on how it’s possible to build gain stages that modify the applied change to an audio signal in proportion to a separately applied control signal. If you have a number of control signal generators available, and can choose which control signal to apply to other gain stages, then you end up with a number of VCA/ DCA assignments. Connect a fader to the control signal generator such that the control signal is modified by that fader, and you have a VCA that’s intuitive to manage.

The VCA/ DCA concept, then, is that of a control group. When you assign faders to a control group, you are directing the console to maintain the relative balance that you set amongst those faders, while also giving you an overall level control for all of those channels at once.

“Like routing all those channels through a bus?” you ask.

Yes and no. The magic of the VCA/ DCA is that you get bus-like level management, but your routing is unaffected. In other words, VCA/ DCA groups are control groups independent of audio signal considerations. This was a big deal for me with Pigs Over The Horizon, because of how we did the playback FX.

The playback FX were in surround. Two channels were routed up front (in mono, actually), with two more channels that were sent directly to surround left and surround right, respectively. Once the surround channels were “lined up” with respect to each other and the feeds to the front, I didn’t want to change that relationship – but I DID want to be able to ride the overall FX cue volume if I had to.

I couldn’t achieve what I wanted by busing the four FX channels together; They would all have ended up going to a single destination, with no way to separate them back out to get surround again. By assigning them to a DCA group, though, it was a cinch. The routing didn’t change at all, but my ability to grab one control and regulate the overall volume of the unchanged balance was established.

Of course, busing is still a very important tool. You need it whenever you DO want to get a bunch of sources to flow to a single destination. This might not just be for simple combining. You might want to process a whole bunch of channels with exactly the same EQ and compression, for example, and then send them off to the main output. If that’s not what you’re after, though, a VCA/ DCA group is a great choice. You don’t chew up a bus just for the simple task of grouped volume control, and if you change your mind on the routing later it’s not a big deal. Your grouped controls stay grouped, no matter where you send them, again, because of that “independence” factor. The VCA/ DCA has nothing to do with where signals are coming from or where they’re going – it only changes the gain applied.

I personally am not as heavy a user of VCA/ DCA groups as some other audio humans, but I see them as a handy tool that I may end up leveraging more in the future. I’m glad I know what they are, because they’re a great problem solver. If your console has them, I definitely recommend becoming familiar with their usage. The day may come when you need ’em!


The Pro-Audio Guide For People Who Know Nothing About Pro-Audio, Part 7

Amplifiers and loudspeakers bring us to the end of my series for Schwilly Family Musicians.

Please Remember:

The opinions expressed are mine only. These opinions do not necessarily reflect anybody else’s opinions. I do not own, operate, manage, or represent any band, venue, or company that I talk about, unless explicitly noted.

Want to use this image for something else? Great! Click it for the link to a high-res or resolution-independent version.

“Now that we’ve turned audio into electricity and back again, we’ve reached the end of this series.”


This article is available, for free, right here.


The Pro-Audio Guide For People Who Know Nothing About Pro-Audio, Part 6

I believe in life after the console.

Please Remember:

The opinions expressed are mine only. These opinions do not necessarily reflect anybody else’s opinions. I do not own, operate, manage, or represent any band, venue, or company that I talk about, unless explicitly noted.

Want to use this image for something else? Great! Click it for the link to a high-res or resolution-independent version.

“The point of loudspeaker management is to make final, overall adjustments to console output so that devices which actually create acoustical output (speakers, that is) can be used most effectively.”


The rest of this article is available – free! – right here.


130 dB Disbelief

It’s hard for me to believe that 130 dB is possible from some loudspeaker designs.

Please Remember:

The opinions expressed are mine only. These opinions do not necessarily reflect anybody else’s opinions. I do not own, operate, manage, or represent any band, venue, or company that I talk about, unless explicitly noted.

Want to use this image for something else? Great! Click it for the link to a high-res or resolution-independent version.

When a manufacturer claims that a loudspeaker system (say, a two-way arrangement in a single, vented enclosure) can create a 130 dB SPL peak at 1 meter with a 1000 watt peak power input, I’m a skeptic. Or rather, I should say that I’m a skeptic about how useful that 130 dB actually is.

What I’m getting at is this: A 1000 watt input is 30 dB above the 1 watt input level. Getting a direct-radiating cone driver to give you 100+ dB SPL of sensitivity in a consistent way is challenging (thought I will not say it’s impossible). There are, of course, plenty of drivers available that will get you over that mark of 100 dB @ 1 watt/ 1 meter, BUT, only with the caveat that the 100+ dB sensitivity zone is confined to a “smallish” peak around 2 kHz. The nice, smooth part of the response that doesn’t need to be tamed is probably between 95 – 97 dB. If you’re lucky, that zone might be just south of 100 dB.

When it comes to useful output, what really matters is what a driver can do with minimal variation across the bandpass it’s meant to reproduce. Peaks in different frequency ranges aren’t helpful for real work – although they do let you claim a higher peak-output number.

My disbelief, then, is rooted in the idea that any “affordable by mortals” loudspeaker model is probably not using an ultra-high performance, super-custom-built cone driver for the low-frequency bandpass. Sure, it might not be a driver that you can get off the shelf, but it’s tough for me to have faith that the very upper edge of loudspeaker performance is being tickled by whatever got bolted into the enclosure.

Now…I could be very wrong about this. In fact, I would prefer to be wrong, because I will always desire an affordable speaker that takes up no space, has no weight, and is infinitely loud from 20 Hz to 20,000 Hz. Anything that gets closer to that impossible goal is a box I can welcome. At the same time, I prefer (and encourage) pessimism when reading manufacturer ratings. Sure, they say the box can make 130 dB peaks, but under what circumstances? Only at 2 kHz? Only when combined with room reflections?

If the numbers you claim are difficult to achieve, I’m going to need more than your word to accept them.


The Pro-Audio Guide For People Who Know Nothing About Pro-Audio, Part 5

Buses are what put the “mixing” in mixing consoles.

Please Remember:

The opinions expressed are mine only. These opinions do not necessarily reflect anybody else’s opinions. I do not own, operate, manage, or represent any band, venue, or company that I talk about, unless explicitly noted.

Want to use this image for something else? Great! Click it for the link to a high-res or resolution-independent version.

“The most common destination for a channel’s signal is a bus. Buses are really what make a mixer a mixer: They’re signal lines meant to carry and combine a number of individual channel signals fed into them.”


I wrote this article for Schwilly Family Musicians. The rest of it is available for free, right here.


Micing A Saw

Contact transducers are really nifty, but take some doing to use.

Please Remember:

The opinions expressed are mine only. These opinions do not necessarily reflect anybody else’s opinions. I do not own, operate, manage, or represent any band, venue, or company that I talk about, unless explicitly noted.

Want to use this image for something else? Great! Click it for the link to a high-res or resolution-independent version.

You may eventually be asked to transduce the noises produced by a saw. I’m not talking about sound effects for film, here. I’m talking about music. A handsaw with a sufficiently manipulable blade can be played very effectively with a violin bow. The resulting emanations are what I would call “a wood-shop Theremin.”

I have effectively captured these sonic events with regular microphones. As with anything else, a unit that basically sounds like the thing it’s pointed at will generally be fine. The troublesome element really is that saws don’t have the kind of body that creates a lot of output. Their resulting lack of SPL can pose a challenge when they’re put into an ensemble, because almost anything else is going to be much, much louder.

As a result of the above, I have, (for years) wanted to try using a contact transducer on a musical saw. I finally got my chance a couple of weeks ago. I was very pleased with the outcome, because I could actually hear some of what the saw was doing in the context of a very busy band.

The key to the whole thing was a Dean Markley Artist Transducer. It’s essentially a gussied-up piezo, with the element potted in some kind of polymer that sits in a wooden surround. The bottom of the pickup has that poster-tack Silly Putty applied, so you can temporarily stick the thing to a surface. As with any piezo-based transducer, you’ll want to connect it through an active DI box; The ultra-high impedance of the op-amp will stop you from loading down the pickup.

Contact micing lives and dies on placement, even more so than regular microphones. Parking the transducer in a bad spot can get you very strange results, but there’s more to the story: The pickup’s physical contact changes the vibrational behavior of the surface that it’s connected to. As such, you want to find a spot where you’ll get good transfer of the instrument’s movement, while avoiding a placement that dampens that same vibration. With a saw, that means that you’ll probably want to search for a place that’s as close to the handle as possible. This serves the dual purpose of keeping the transducer and cable out of the way, while also allowing the blade to move freely.

You will also want to make sure that you have the ability to DRASTICALLY reduce the high-frequency output of the saw channel. (A freely sweepable low-pass filter is the best case.) I’m starting to form a theory that vibrating surfaces and air create a sort of acoustical inductor – a device that impedes high-frequency output. Take away the transition to air-carried waves, and a lot of information that you’re not used to hearing comes into play. The bow scraping against the blade is hard to hear with traditional micing, but a contact mic really brings that sound through. We ended up rolling the filter down rather far…like, 1 kHz far, before a result was created that wasn’t too jarring.

All of this takes some work and planning, certainly, but the end result of much, much, MUCH improved gain-before-feedback can be tremendously helpful. Consider getting a contact transducer for your box-of-goodies. It might prove to be a highly handy tool one day.


Graphic Content

Transfer functions of various reasonable and unreasonable graphic EQ settings.

Please Remember:

The opinions expressed are mine only. These opinions do not necessarily reflect anybody else’s opinions. I do not own, operate, manage, or represent any band, venue, or company that I talk about, unless explicitly noted.

Want to use this image for something else? Great! Click it for the link to a high-res or resolution-independent version.

An aphorism that I firmly believe goes like this: “If you can hear it, you can measure it.” Of course, there’s another twist to that – the one that reminds you that it’s possible to measure things you can’t hear.

The graphic equalizer, though still recognizable, is losing a bit of its commonality as an outboard device. With digital consoles invading en masse, making landings up and down the treasure-laden coasts of live audio, racks and racks of separate EQ devices are being virtualized inside computer-driven mix platforms. At the same time, hardware graphics are still a real thing that exists…and I would wager that most of us haven’t seen a transfer function of common uses (and abuses) of these units, which happen whether you’ve got a physical object or a digital representation of one.

So – let me dig up a spare Behringer Ultragraph Pro, and let’s graph a graphic. (An important note: Any measurement that you do is a measurement of EXACTLY that setup. Some parts of this exercise will be generally applicable, but please be aware that what we’re measuring is a specific Behringer EQ and not all graphic EQs in the world.)

The first thing to look at is the “flat” state. When you set the processing to “out,” is it really out?

In this case, very much so. The trace is laser flat, with +/- 0.2 dB of change across the entire audible spectrum. It’s indistinguishable from a “straight wire” measurement of my audio interface.

Now, we’ll allow audio to flow through the unit’s filtering, but with the high and low-pass filters swept to their maximums, and all the graph filters set to 0 dB.

The low and high-pass filters are still definitely having an effect in the audible range, though a minimal one. Half a decibel down at 45 Hz isn’t nothing, but it’s also pretty hard to hear.

What happens when the filters are swept to 75 Hz and 10 kHz?

The 3dB points are about where the labeling on the knobs tells you it should be (with a little bit of overshoot), and the filters roll off pretty gently (about 6 dB per octave).

Let’s sweep the filters out again, and make a small cut at 500 Hz.

Interestingly, the filter doesn’t seem to be located exactly where the faceplate says it should be – it’s about 40% of a third-octave space away from the indicated frequency center, if the trace is accurate in itself.

What if we drop the 500 Hz filter all the way down, and superimpose the new trace on the old one?

The filter might look a bit wider than what you expected, with easily measurable effects happening at a full octave below the selected frequency. Even so, that’s pretty selective compared to lots of wide-ranging, “ultra musical” EQ implementations you might run into.

What happens when we yank down two filters that are right next to each other?

There’s an interesting ripple between the cuts, amounting to a little bit less than 1 dB.

How about one of the classic graphic EQ abuses? Here’s a smiley-face curve:

Want to destroy all semblance of headroom in an audio system? It’s easy! Just kill the level of the frequency range that’s easiest to hear and most efficient to reproduce, then complain that the system has no power. No problem! :Rolls Eyes:

Here’s another EQ abuse, alternately called “Death To 100” or “I Was Too Cheap To Buy A Crossover:”

It could be worse, true, but…really? It’s not a true substitute for having the correct tool in the first place.


That Fibber, Myself

I was never going to buy wireless gear again. Until…

Please Remember:

The opinions expressed are mine only. These opinions do not necessarily reflect anybody else’s opinions. I do not own, operate, manage, or represent any band, venue, or company that I talk about, unless explicitly noted.

Want to use this image for something else? Great! Click it for the link to a high-res or resolution-independent version.

There is a taxonomy of falsehood. For instance, a particularly awful and hurtful falsity might be “a lie from hell.” Slightly less severe versions might be “a fib from heck,” or “a half-truth from West Jordan.” “Tall-tales from Hyrum” never really hurt anyone, as is the case for a “whopper from Utah County.”

In any case, I thought I was telling the truth when I said – to many people, repeatedly and emphatically – that I would never again put my own money into wireless audio. I was adamant. Determined. Resolute now to defend fair honor upon the glorious field of contest, I say to thee, Knights of the West, STAND!

Yeah, well, you can see how that turned out. Maybe what I said was “a fiction from Erda.” I’m not really sure.

Here’s what happened. I subcontract for a local production provider. A New Years Eve show had been on the books for quite a while, only for it to suddenly vanish in a cloud of miscommunication. The provider scrambled (thank you!) to find a show for me to do, so that I’d have a job that night (thank you!). Normally, we’d have time to handle some coordination for the show advance, but this was a situation where haste was demanded. The provider thought that I had a couple of wireless handhelds available. The show was specced, booked, and advanced. About a day and a half before downbeat, I got the input list.

A strict requirement was at least one wireless handheld. Eeeeep!

It was too late to cross-rent from one of our shared connections. My favorite place to buy or rent “right now” items was closed for inventory. I grabbed my credit card and drove to The Geometric Centroid of Strummed Instruments. (Think about it.) I was in and out in a jiffy, carrying with me a Beta58 Shure GLXD system. As much as the 2.4 Ghz band is becoming a minefield, I went with a digital system; If I was going to spend the money, I did NOT want a unit operating in a part of the spectrum that the FCC would end up auctioning or re-apportioning.

I could have gotten something significantly cheaper, but I wouldn’t have been as confident in it. My imperative was to bring good gear to the show. If I brought something from the bargain-bin, and it ended up messing the bed, that would be hard to excuse. If a better unit misbehaved, I could at least say that I did my due diligence.

In any case, the show had to go on. I’m still not a fan of wireless. I still don’t intend to add to my inventory of audio-over-airwaves devices. Even, so, you sometimes have to bend yourself around what a client needs in a short timeframe. It’s just a part of the life. Of course, after the show, my brand-new transmitter had lipstick embedded in the grille, but that’s a whole other topic…


The Pro-Audio Guide For People Who Know Nothing About Pro-Audio, Part 3

Onward to the microphone preamp…or trim.

Please Remember:

The opinions expressed are mine only. These opinions do not necessarily reflect anybody else’s opinions. I do not own, operate, manage, or represent any band, venue, or company that I talk about, unless explicitly noted.

Want to use this image for something else? Great! Click it for the link to a high-res or resolution-independent version.

“Signals at mic-level may require large, positive gain changes to correctly drive downstream electronics, and so a jack that can be connected to a microphone preamp is needed in that case.”

Read the whole thing, free, at Schwilly Family Musicians.