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Apogee Mini?MeHigh-quality audio preamps, compression and A/D conversion in a portable unit
Measuring 10 long by 5 wide and 1 tall, the Mini?Me is designed for mobile recording (it can operate from either the included 12V power supply or on battery power ranging from 6V to 16V). Just hook it to a USB-equipped laptop loaded with your favorite audio recording app, and youre ready to capture a high-quality stereo audio signal. If you don't have USB, AES/EBU and S/PDIF digital outputs are also included. The output options include 16-, 20- or 24-bit audio at 44.1, 48, 88.2 or 96 kHz. The USB output is limited to 44.1/48kHz, while the AES/EBU (XLR) and S/PDIF (RCA/coaxial) digital outputs can handle everything up to 96 kHz. Apogee also makes a version without USB for $1,295 (MSRP).
With all it includes, the Mini?Me is a downright bargain. Its high-quality preamps, compressor/limiter and A/D converters are ready for any professional situation, on the road or in the studio. There's 48v phantom power for microphones and a headphone jack for monitoring. And because its outputs are clocked by a high-stability reference crystal oscillator, the Mini?Me can even serve as a master clock.
Apogee Electronics (www.apogeedigital.com) has somehow packed all this functionality into a compact unit that doesn't feel cramped or awkward. The knobs are accessible, and the LED input meters are easy to read. In a clever bit of ergonomic design, the two analog input jacks serve double duty as XLR and TRS inputs.
|Front View: The Mini-Me comes in a handsome extruded metal case with purple knobs. LED meters and input volume controls are at left, compression and sample rate settings are in the center, and phantom power button is at near right.|
|Rear View: Input jacks at right double for XLR or TRS plugs. USB and headphone monitor jacks are in the middle, while AES and S/PDIF digital outputs are at left.|
The compressor/limiter is equipped with two proprietary Apogee processes, Soft Limit and Push-IT. Soft Limit is an analog process that prevents digital overs by rounding out peaks in the incoming signal, beginning on peaks at about 4dBFs and smoothing them out up to 0dBFs. Push-IT is a gain control circuit consisting of a compressor and limiter that are integrated with Soft Limit. Push-IT gives you extra boost when you need it or slams on brick-wall limiting when the signal rises above a certain decibel level .
Between the two, you can adjust an incoming signal for maximum saturation without distortion. The graph below shows the various compression and limiting curves generated by the combination of Soft Limit and Push-IT.
|3 (curve starts at 14 on the left axis) This shows the response curve of SLC setting Compression 3. Top switch in far right ?SLC position, bottom switch far right in curve ?3 position.|
off (curve runs from the origin, bottom left, to +0/-0) Circuit bypassed. Top switch in far left ?off position.
SL (curve runs from the origin to +2/-0) This shows the response curve of Soft Limit only. Top switch in center ?SL position. The bottom switch position is not relevant.
2 (curve starts at -25.5 on the left axis) This shows the response curve of SLC setting Compression 2. Top switch in far right ?SLC position, bottom switch in middle curve ?2 position.
1 (curve starts at the origin and exits right at about -1.5 dBFS) This shows the response curve of Soft Limit/Limit 1 circuit. Top switch in far right ?SLC position, bottom switch in far left curve ?1 position.
This is a well-built professional product that sounds terrific. In fact, although its designed for mobile applications, its fully suitable for studio use. I used the USB output with equally good results recording to both a Mac G4 running OS X 10.2.6 (with BIAS Deck 3.5.2 as the host application) and a Windows 2000 machine (running SONAR 2.2). I also hooked the Mini-Me up to the AES and S/PDIF inputs of a Mackie d8b digital mixing console and recorded an acoustic guitar. All three inputs (USB, AES and SPDIF) produced sparkling clear recordings from the mic preamps, using the compressor and A/D conversion.
|The Mini?Me in its optional carrying case (MSRP $49.95).|
And the A/D conversion is first-rate I hooked a CD player into the Mini-Mes analog inputs and then routed the AES digital output into the Mackie d8bs digital inputs. There was an audible improvement in the high-end frequencies, compared to the sound of the CD player going straight to the mixer.
The Mini?Me has another handy conversion trick, too: If you get the sample rates mismatched between the Mini?Me and your computer, the unit will convert sample rates automatically. Or, if you select, for example, 24-bits on the unit and 16-bits on the computer, the Mini?Me will automatically apply UV22HR conversion encoding (more on this below) to the signal sent to the USB port (at 44.1/48 kHz only).
|The UV22HR Encoding Process |
Excerpted from the Mini•Me Manual
|If you are producing recording for 16-bit CD – or 20-bits for many DVD-Video projects – then you need a method of reducing the high resolution 24-bit output of a modern conversion system to 16 or 20 bits. Apogee UV22HR Encoding – the latest and most powerful development of Apogee’s original UV22 process – is an entirely different approach to word-length reduction. UV22HR does its job without sonic compromise, and without adding a sound of its own, preserving the sound stage and tonal balance of the original high-resolution source. The effects are even audible on original 16-bit recordings. |
UV22HR Encoding adds an inaudible, algorithmically-generated concentration of energy around 22 kHz. Technically, it’s known as “Sub-Nyquist-band dither”. Much as the bias on an analog tape recorder smooths out magnetic tape recording non-linearities, UV22HR silently captures resolution beyond 20 bits on a standard, 16-bit CD. In addition, this inaudible carrier smooths the rough edges of even the most inexpensive CD player or external converter. UV22HR makes your recordings sound better on all listening systems.
The truly unique statistical properties of UV22HR guarantee a constant white noise floor, very similar in character to analog tape noise, no matter what the input source. If you listen to a UV22HR encoded recording, you can hear a stable, accurate sound stage and faithful tonal balance more than 24dB into the noise – just as you do on analog tape.
Yet the UV22HR’s low audible noise floor sits at the theoretical limit for a 16-bit or 20-bit system. Nothing is lost – but a great deal is gained. In listening test after listening test, engineers and reviewers alike choose UV22 over all other systems. Many thousands of CD titles have already been mastered using Apogee UV22 and UV22HR processors. Apogee’s process is today in use in the vast majority of US mastering houses, and it is estimated that as many as 80% of the hit records mastered in the United States today utilize the system.
Another great inclusion in the Mini?Me for those who have to convert down from 24-bit to 20 or 16 bits is Apogees proprietary UV22 encoding process. This performs bit reductions that retain most of the sonic characteristics of the high bit-rate signal.The Mini?Me has an upgraded version called UV22HR (see sidebar).
In fact, given the Mini?Mes range of features, a professional sound card isnt even required for outstanding digital audio recordings. With a signal path going right from the analog source into the Mini?Mes converters, and then to the computer via USB, the signal quality is at least comparable to, and probably better than, what youd get through most sound cards. And of course, you can mix multiple audio tracks in your software application, so a mixer isnt required, either.
This is important to mobile recordists, but its also an economical way for a home studio to get professional-sounding results. Going direct from the Mini?Me to the computer without a mixer, you can only record two tracks at a time. Even if you had a mixer, the Mini?Me has only two channels anyway. But if youre multitracking, as opposed to recording a number of separate tracks live, the two-channel limit doesnt matter. And what youd save on a good sound card and a mixer is about the cost of the Mini?Me.
If youre looking for a professional dual-platform audio interface for mobile recordings, the Mini?Me fits the bill perfectly. Its great for independent filmmakers (itll ouput digital black) or radio interviewers in the field, or even, as Mercenary Audios Fletcher points out, Deadheads wanting to make concert bootlegs (the band permits this). But its also a great option for project studio owners who need high-quality mic preamps and A/D conversion. In addition, the Mini?Mes UV22HR makes it an ideal final step between a computer sound card (or outboard mixer) and a mastering device. This device is a clear winner, and merits serious consideration from audio professionals, field recordists and project studios alike.
Related Keywords:Apogee, Mini Me, audio, preamplification, compression, limiting, USB, recording