Studio Technologies 742 Audio Mixer

By Steve Murphy | Originally published in Radio World magazine

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Skokie, Ill.-based Studio Technologies recently introduced two single-rack unit audio mixers specifically designed for use in ENG vehicles: the single-bus model 740 ($995) and a dual-bus model called the 742 ($1,095).
Despite their deceptively simple user interfaces, both mixers feature a healthy set of ENG or general broadcast features.

FEATURES
The Model 742, reviewed here, is designed for quick setup and simple front-panel operation; a set of internal jumpers can further customize its operations. The unit is designed for balanced +4 dBu systems.
The mixer features eight mono inputs, the first four of which are mic/line-selectable and the remaini ng four are linelevel only. Individual inputs can be assigned to either or both of its two mono output busses.

All the 742’s external controls are located on the front panel and all input/output connections are on the back. On the front panel, each of the eight input sections features a gain knob, output bus assignment toggle switch (1, 1+2, 2) and a dual-color LED signalpresent/ peak-level indicator. Channels 1 through 4 are mic- or line-level selectable by pushbutton.

The four mic/line inputs provide a linelevel gain range of -32 to +28 dBu, and a mic-level gain range of -76 to -8 dBu; the line-level only inputs range from -14 to +28 dBu. The status LED lights green when a signal is at least 18 dB below the nominal internal operating level, and the LED lights red when the input signal is within 6 dB of the input circuitry’s maximum level. A global 12 V phantom power circuit can be activated for the four mic inputs using an internal jumper.

The front-panel output section features dual-channel concentric knobs for setting master and monitor output levels. Dual 10-segment LED meters display the levels at the main outputs. The 742 features a studio-grade twochannel output compressor circuit.

Fast Facts

Application: Field audio mixing
Key Features: Four mic/line XLR inputs, four line-only XLR inputs; studio-quality compressor; 10-segment LED meters.
Price: $1,095
Contact: Studio Technologies, Inc. 847-676-9177 www.studio-tech.com

Though the compressor has no external controls, it can be internally configured to engage when the main outputs reach +10 dBu (factory default) or +6 dBu, or it can be bypassed; two yellow LEDs on the front panel indicate when the compression circuit is active.

The 742 also has a built-in tone generator for level calibration. A front-panel switch sends the tone generator to the main output busses. In addition, Studio Technologies provides a dedicated tone output on the rear panel that is always active. The tone generator produces +4 dBu sine wave at 400 Hz or 1 kHz (jumper-selectable).

On the back panel are eight female XLRs for signal input, two male XLRs for main outputs, two 1/4-inch TRS jacks for monitor outputs, a 1/4-inch TRS tone output and a stereo headphone jack.

IN USE
The Studio Technologies Model 742 is principally designed for ENG truck use. In this application, the 742’s streamlined set of controls and rock-solid build quality are just what the chief engineer ordered. In addition to the front-panel controls, Studio Technologies endowed the 742 with a useful range of critical calibration controls and global operational settings, and wisely put them inside the box.

In most studio applications, having those controls locked away might prove frustrating. In the fast-paced, turn-itup- and-go world of newsgathering, however, the unit will already be set up and calibrated for the truck’s normal operations. The end user is presented only with a near-infallible set of controls; in a pinch, anyone should be able to operate this device. The 742 suits this purpose perfectly, and provides an impressively clean signal path to boot.

The thing I liked best about the 742 compared to other single-space mixers I have used is that it achieves a dual-bus configuration in a useful and thoughtful manner. Though it could be used for stereo applications, the 742 is really built as a dual-mono bus mixer. Since most ENG trucks are working with mono signals, Studio Technologies installed toggle switches (as opposed to panpots) to assign channels to the output busses. This allows the engineer to create two independent feeds without worrying about unwanted leakage due to improperly set or uncalibrated panpots.

If not used for sending two feeds, the second bus can also be used to monitor external audio sources within the truck, completely independent of the broadcast feed. Alternately, if the second bus is not being used at all, flipping an input channel’s toggle switch to the dead bus acts like a channel mute switch.

I want to compliment Studio Technologies on the physical build and circuit component quality of the 742.
Looking inside the unit reveals a number of high-end design elements (including sealed relays for the mic/line switch and the same compressor VCA as used by dbx and others), a high-quality toroidal power transformer and clearly labeled jumpers and trimpots. Likewise, the operational manual is well-written and technically comprehensive.

During my testing of the 742, I did find some problem areas and a few items for my wish list.
The biggest problem I had was with the concentric output knobs. I found that adjusting the center pot (Channel 1) would occasionally move the outside pot (Channel 2) as well. Depending upon where the initial levels were set, I could get a change of 3 dB or more on the outside knob when quickly fading up or down the inside knob; this occurred on both the main and monitor output knobs. The obvious workaround is to hold the outside knob while turning the inside knob.

The other problem I had with the 742 is that it has no LED indicating the unit is powered up. This could give the uninitiated operator a minor heart attack and/or send troubleshooting in the wrong direction if audio problems arise.
Also on my wish list would be center detents at unity gain for the main and monitor output knobs, or even fully detented knobs across the range (which may also prevent the earlier slippage problem). A front-panel headphone jack would also be nice, but it is clear there just isn’t room to spare.

In talking with Gordon Kapes at Studio Technologies, he informed me that the company has addressed my concerns by modifying the design of the dual rotary level control (potentiometer) to minimize the chance that the two sections could mechanically rub together. Also revised was the circuitry associated with one of the front-panel LEDs to provide a power present indication and a mechanical detent was added to assist users in quickly setting the default levels. Due to long lead times for custom parts, these changes will become part of production Model 742 units over the next several months, Gordon said.

SUMMARY
Studio Technologies designed the 742 for ENG vehicle use, with all essential controls at your fingertips; critical controls that may impede its quick and foolproof operation are relegated to the inside of the unit. From its dual-mono bus architecture to its high-quality output compressor section, the rock-solid, single-rack 742 provides a great deal of flexibility and an impressively clean output signal.

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O.C. White Desk-Mount Boom Stand

By Steve Murphy | Originally published in Radio World magazine

 

Business is booming – quite literally – for Mass.-based O.C. White. The company manufactures a range of industry-specific lighting and mechanical products with one thing in common: adjustable boom arms.

Otis Charles White, a small-town dentist founded his eponymous company in 1894 with his pioneering design for a gas-fueled adjustable dental light.ocw_51900

The company’s adjustable magnification and lighting products are ubiquitous in many disciplines and areas of manufacturing including medical, photographic, quality control, critical safety inspection, microscope lighting and electronic magnification.

Microphone boom arms are a natural extension of the company’s industrial reach, so it should be no surprise that O.C. White has been successful in the broadcast industry as well.

Features

For this review, O.C. White provided a ProBoom Elite 61900-BG arm that features two spring-loaded adjustable segments and a fixed base/riser.

The riser/base is a 15-inch vertical metal tube that has a rectangular 3-inch by 2-3/4-inch base that permits either through-the-counter wiring or side exit. Four screw holes are provided for attaching the base to the target surface.

The riser comes prewired with a Gepco 24-AWG microphone cable that terminates in a female XLR jack near the top of the riser. A nonterminated four-foot length of the cable extends from the riser base for attaching to a connector or patch bay or other existing audio system.

Product Capsule

Thumbs Up

Well-constructed

Sturdy enough for heavy broadcast microphones

Thumbs Down:

Must be permanently mounted to solid desk surface; an optional 2-inch capacity table-edge clamp is available as an option

Price: $199

For more information contact the company in Massachusetts at (413) 289-1751 or visit www.ocwhite.com.

A 40-inch XLR cable is required to get the signal from the microphone to the female XLR jack at the top of the desk-mount riser. A removable plastic strip hides the wire channel running down the spine of each segment. This strip permits quick and easy installation of the user’s microphone wire. Simply drop the wire in place and zip the wire covers in place.

The two-segment spring-loaded boom arm attaches to the riser via a heavy-duty swivel socket. Each arm segment measures 18 inches and features two soft gold-plated “music wire springs.” O.C. White states that the ProBoom arm can hold up to eight pounds when used with the optional heavy-duty springs.

Mounting

Mounting the riser and boom assembly to my desktop using appropriately sized wood screws was quick and straightforward. But it did not take long for me to realize that the corollary to a heavy-duty boom arm design that holds up to eight pounds is that a greater amount of force is required to move the arm, especially at the joint just above the riser.

This force, in turn, transfers to the spot where the base attaches to the desk. The screw holes already showed signs of loosening.

I removed the screws, drilled clear through the solid oak surface and switched to the widest bolts that would fit through the base holes, fastened on the underside with nuts and large diameter washers. The heavy-duty arm now had appropriately heavy-duty mounting – desk and mic arm were now evenly matched.

Although this experience should probably be considered “operator error,” I relay it as a warning to all who intend to mount this arm on fiberboard-based counters or thin wood surfaces.

Properly mounted, the arm functions with excellent sturdiness that does not stray from its designated position (a continual annoyance endemic to cheaply built spring arms).

The well-matched soft gold-plated springs generally are quiet, as advertised, providing a professional on-air performance. Normally, care should be taken in making sure the springs have not migrated toward contact with the arm assembly over time – metal against metal does not a quiet arm make. The ProBoom, however, has integrated slots in the spring holders that is claimed to prevent the springs from moving from their original position.

Summary

As in other industries, O.C. White’s broadcast microphone arms are a success story. With proper mounting and minimal care, this mic arm should withstand many years of continuous, high-traffic studio use. To wit, O.C. White backs its product with a lifetime warranty.

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Joemeek Goes Micro With the MQ1

By Steve Murphy | Originally published in Radio World magazine

Desktop DJs and voiceover artists take note: Joemeek is coming over and he wants to move into your spare drive bay.

Fletcher Electronics, based in Torquay, England, is known for its line of bright green preamps and compressors inspired by Meek, the late pioneering engineer. With the introduction of the MQ1 recording interface ($299.99), Fletcher takes classic Joemeek circuitry and retrofits it into a green drive bay-mountable box for the desktop recojoemeekrding market. 

MicroMeek range

The MQ1 is one of several devices in the relatively new “MicroMeek” range. These diminutive products feature the same circuitry found in the bigger, more expensive Joemeek products but with fewer features (no analog VU meters, built-in power transformers or full rack cases).

Product Capsule

Thumbs Up

Big sound, small price

Logical layout

Great for broadcast use

Full recording channel complement (preamp, compressor and equalizer)

Thumbs Down

Limited placement/visual sightlines due to computer mounting

Confusing marketing (not a soundcard or computer interface)

Price: $299.99

For more information contact PMI Audio Group in California at (310) 373-9129 or visit www.pmiaudio.com

The audio signal path, however, has not been downsized – the MicroMeek line boasts the famous Joemeek sound as their big brothers.

The MQ1 mounts in a PC or Mac drive bay and works in conjunction with the computer’s existing sound card. The unit derives its operating power and +48 volt phantom power directly from the computer power supply.

With the exception of a front-panel instrument 1/4-inch input jack, inputs and outputs are accessed via a panel mounted in the back of the computer. This panel is host to a pair each of balanced 1/4-inch auxiliary inputs and main outputs. An XLR breakout cable emanates from the top of the panel, just under which is a +48-volt phantom power button.

Logical layout

The front panel of the MQ1 is densely populated with knobs, switches and LEDs, yet they are laid out in a logical manner.

A switch enables MicroMeek microphone or instrument input when turned on. When off, the auxiliary inputs are fed directly to the computer’s sound card.

The next two controls are the input gain and compression knobs. Input attenuates the incoming level fed by either the XLR microphone line or 1/4-inch instrument jack. It has no effect on signals at the auxiliary inputs. The hybrid compression knob essentially acts as the optical compression circuit’s “threshold” control.

The ATT button chooses between two preset compressor attack times (1 or 5 ms) and the REL button sets the release time of the compressor (500 or 1,500 ms).

Next is the Meekqualizer section, a three-band +/-16 dB EQ. The LF and HF knobs are shelving filters set to 80 Hz and 8 kHz respectively. The MF filter is a peaking filter centered around 1.8 kHz with a Q value of one.

OUT VOL is a final stage volume control for the output of the MQ1. It operates after the three-stage LED VU meter and does not affect the overload margin.

No software to install

In keeping with the computer product paradigm, Fletcher Electronics forgoes a printed manual in favor of an electronic version provided on an enclosed “installation” CD. The CD contains demo software from Sonic Foundry, Cakewalk and others. I put installation in quotes because, with regard to the MQ1, there is no software to install.

Here I think the MQ1 is being marketed in a misleading way and I am not sure why, for the MQ1 is a worthwhile idea that sounds great and is a great value.

Fletcher Electronics should be more straightforward with what it has: a single channel preamp, compressor and equalizer that has no dealings with the host computer other than that they utilize the same power supply.

Yet the unit is called the MQ1 PC/Mac Recording Interface and contents of the package include the aforementioned Installation CD (though it requires installation drivers no more than any other preamp you own). A 26-way Audio/Data Cable (which carries no computer data) attaches the preamp unit to the MicroMeek Connection Card, “requiring a free PCI or ISA slot.”

This last bit is more than a little confusing because it clearly implies the ill-named Connection Card is a card that mounts in a card slot, though it is simply a back plane-mounted breakout panel to access the unit’s audio I/O.

Marketing rant aside, the MQ1 sounds and acts like the other Joemeek products I have used (and owned) – and that is a good thing.

Once I found the ideal ground connection within my computer (grounding cable included), I experienced no unusual buzzes, noises or hums despite the unit’s proximity to the sonically hostile environment inside a computer.

The vocal quality that the MQ1 and similar Meek units produce is perfect for voiceover and broadcast use. With proper adjustment of the compressor and equalizer sections, the resulting vocal sound can only be described as warm and full, yet upfront and present – crisp yet commanding. It doesn’t get any better for radio.

For experienced audio producers, operation of the MQ1 is intuitive. For beginners in audio production, operation of the unit should be straightforward and learned quickly, provided they read the well-written basics explained in the brief electronic handbook.

Despite some identity issues, there is no doubt the MQ1 is another great-sounding product from the Joemeek/Fletcher Electronics folks. The MQ1 is designed especially for those who record to a nearby computer.

As with any other recording channel, frequent visual and hands-on access of the MQ1 is required for proper setting of gain structure and compression – make sure that mounting the Meek unit in your computer will not be overly limiting.

For more flexibility in preamp placement, consider the slightly more expensive MicroMeek MQ3, a standalone model with its own power supply (wall transformer) and a few extra features. Either way, you won’t be disappointed with the sound.

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VXpocket 440 Laptop Audio Interface

By Steve Murphy | Originally published in Radio World magazine

 

by Stephen Murphy

Four years ago, Digigram made laptop and desk-bound computer users stand up and take notice with the introduction of the first professional-grade audio recording interface on a standard Type II PC card. images

Designed to enable audio production on a laptop computer, the diminutive two-channel VXpocket offered portable performance on par with its full-sized PCI card counterparts.

Digigram engineers have outdone themselves with the recent release of the more powerful four-channel VXpocket 440 recording interface ($650).

Feature set

The Digigram VXpocket 440 features four balanced analog inputs (at microphone or line level), four balanced analog outputs, S/PDIF digital input and outputs, and a SMPTE (LTC) time-code input.Input/output connectors are located on a heavy-duty breakout cable that clips in to the top of the VXpocket 440 card. The cable is outfitted with eight XLR connectors for the analog I/Os, three phono (RCA) connectors for S/PDIF digital I/O and SMPTE input, plus a stereo 1/8-inch jack for headphone output.

The VXpocket 440, like the updated version of the stereo VXpocket (VXpocket v2) card, offers 24-bit performance with Windows-compatible applications. Direct Sound and Wave drivers are provided for Windows XP, 2000, 98/95 and NT4. In addition to working with applications under MAC OS9 and MAC OSX, cross-platform ASIO drivers are provided.

As with the original VXpocket, the VXpocket 440 can record and play at the standard sampling rates found between 8 kHz and 48 kHz. 


Product Capsule

Digigram VXpocket 440 Type II PC Card Audio Interface

Thumbs Up

Professional I/O connections

Multichannel full-duplex operation

Cross-platform compatibility

Thumbs Down

Only one stereo set of digital I/O

Limited to four total I/O channels at 24-bit/48 kHz

Price: $650

For more information: visit www.digiram.com


Although the card is capable of bidirectional four-channel operation, the actual number of channels is determined by the performance of the host laptop computer and by the sample rate/bit-depth selected. Only bidirectional two-channel operation or four channel record are supported at 24 bits at 48 kHz.

The analog inputs can be switched internally from line level (0 dB) to microphone level (+30 dB or +48 dB) for direct use with dynamic microphones. There is no built-in 48-volt phantom power to enable use of condenser microphones, though several manufacturers sell reasonably small battery-powered phantom power adapters.

Digital input levels can be adjusted internally. The line-level analog and S/PDIF digital output levels are adjustable.

Line-level inputs and outputs can handle a maximum level of +10 dBu; the SMPTE input can read time code levels ranging from -20 dBu to +3 dB and features a capture speed tolerance of +/-15 percent.

Simple install

After downloading the latest drivers from the Digigram site, installation of the card into a Pentium IV 1.2 GHz Dell Latitude C810 (with 256 MB of RAM and a 45 GB internal hard drive running Windows 2000) was reasonably simple.

The software I evaluated the VXpocket 440 with included the Cubase audio and MIDI sequencer from Steinberg and Sound Forge from Sonic Foundry.

The Digigram Wave Mixer application is used to set input and output levels, record source, analog input type, phones level and digital format (AES or S/PDIF). The control application can also switch the card into a “Data” mode, which disables all digital level processing to ensure digital data integrity when outputting non-PCM audio data such as Dolby AC3.

For ASIO operation, a separate control interface is launched from your recording application, allowing control over the card plus the advanced ASIO recording and monitoring settings.

I took the notebook recording system on several remote recording expeditions including press conferences and multi-person interviews. I even took the system with me on my beach vacation to continue working on a personal production.

While typical radio and newsgathering recording traditionally uses two-channel recorders (MD, cassette, DAT, etc.), the extra input channels afforded by the VXpocket 440 came in handy on several occasions during my testing.

At press conferences, for example, the extra channels can be used for coverage microphones in addition to the direct pressbox feed. Having the ambient microphones on separate tracks provides both an auditory safety net and the ability to feed in audience questions not usually available through the press box.

For multiperson interviews, separate channels for each interviewee allows for later mix control and easier editing of difficult transitions.

Flexible, portable

Physically, Digigram made the VXpocket 440 card to be as flexible and as portable as possible. As such, a separate hardware breakout box was ruled out in favor of the provided multiconnector breakout cable.

While this approach makes the laptop recording system self-contained and self-powered, care needs to be exercised regarding the use and anchoring of the breakout cable. It is easy to see that a breakout cable consisting of eight metal XLR connectors and several smaller connectors hanging off of the top of a PC card is a potential recipe for trouble.

To this end, Digigram provides an innovative anchor system that significantly reduces strain on the card by attaching the body of the cable to an empty port (parallel, serial, external monitor, etc.) via two large thumbscrews.

Of course, if someone trips over your cables, your computer is still at risk, but that is hardly the fault of Digigram. It is a good practice with semi-expensive and fragile portable recording equipment to take appropriate precautions, such as using gaffer’s tape, tying long cables to table legs, etc.

Overall, I experienced no troubles and was pleased with the sonic performance and the newfound mobile recording freedom I discovered with the VXpocket 440.

The Digigram VXpocket 440 brings professional multichannel audio performance to the mobile computing market. The convenience and expedience of recording and editing in the same box while on the road is worth the price of the card, especially for busy newsroom operations. It doesn’t hurt that the price recently dropped almost 25 percent, to $650.

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