The Tampa is a Class-A, solid-state preamp that takes an innovativeapproach to achieving tubelike characteristics. According to themanufacturer, the Tampa's Temporal Harmonic Alignment (THA) technologycontrols the phase alignment of added harmonics in a way that preservesthe original sound while emulating tube characteristics in high-gainsituations. M-Audio asserts that the effect goes beyond the midrangeenhancement that tube circuitry typically offers and affects the entirefrequency spectrum equally.
In addition to the new technology, the 2U, single-channel Tampaoffers a symphony of bells and whistles at a reasonable price. Theseinclude a dual optical-servo compressor, a digital output withselectable sampling rate, and variable input impedance.
A SHINING FACE
With its chicken-head knobs, sturdy toggle switches, VU meters, andmetal handles, the Tampa exudes vintage class (see Fig. 1). Atthe far left are the power switch and a 48V phantom-power switch withassociated red LED. The input section, outlined in black, includes aNeutrik combo jack that accepts balanced and unbalanced ¼-inch andXLR inputs, and a toggle switch to select microphone or instrumentlevel. Above that is the variable input-impedance selector, whichoffers four choices: 300ž, 600ž, 1.2 kž, or 2.4 kž.The gain control gives you 34 dB of level, with an additional 20 dB ofboost available at the flip of a switch. To the right of the inputsection is a switchable highpass filter that rolls off 12 dB per octavebeginning at 80 Hz.
Next is the compressor, which includes a bypass switch and controlsfor threshold (-20 dB to +20 dB), ratio (1.1:1 to 10:1), attack (1 msto 10 ms), and release (250 ms to 5 seconds). The left-hand VU metershows the amount of gain reduction.
To the right of those controls are a switchable -20 dB pad, whichaffects the analog output only; an output VU meter that doesn't reflectthe setting of the pad switch; a phase-inversion switch; a red LED thatilluminates when the signal reaches +26.5 dBu (4 dB below thedigital-clip level of +30.5 dBu); and the sampling-rate selector, whichoffers rates of 44.1, 48, 88.2, and 96 kHz.
The rear panel has 24-bit dual-mono S/PDIF and AES/EBU digitaloutputs on RCA and XLR jacks respectively; separate ¼-inch and XLRanalog outputs; and a receptacle for the lump-in-the-line power supply(see Fig. 2). The ¼-inch analog output jack acceptsbalanced TRS or unbalanced TS cables. Both analog jacks pass signalsimultaneously.
FEATURES4.0EASE OFUSE4.0AUDIOQUALITY3.5VALUE4.0RATING PRODUCTS FROM 1 TO5
PROS:Temporal Harmonic Alignment feature. Dual optical-servo compressor.Overdrive feature with 20 dB boost on input and 20 dB pad on output.Highpass filter. Variable input impedance. Digital output. Variablesampling rate. Phase inverter.
CONS:Compressor's maximum attack time is too fast and minimum release is tooslow. No makeup gain on compressor. Enhanced low-end sustain can reduceclarity in some sounds. High-end transients sound dynamicallyflat.
I tested the Tampa next to a number of other preamps — aUniversal Audio 2-610, a Peavey VMP2, a Grace Design 101, a LangevinDual Vocal Combo, an FMR RNP8380, a TubeWorks DI, a Digidesign Digi001, and the preamps in a Mackie 1202-VLZ mixer — to get a senseof how it sounds against a broad range of popular products. I used thepreamp and compressor functions on acoustic guitars, vocals, andpercussion; I checked the DI on electric guitar; and I finished up witha comprehensive loudspeaker test. For the recordings, I used Neumann KM184 and AKG C 3000 B microphones and tracked to Digidesign Pro Tools LEand a Sony PCM800 digital multitrack. I was assisted by engineers SteveOrlando and Myles Boisen.
For a rowdy session with the band Jingle Punx, I ran the output of adistorted Fender Stratocaster through a Line 6 PodXT into theinstrument input on the Tampa. Then I ran the Stratocaster-PodXT combointo a TubeWorks DI going direct into the Digi 001 preamp/converter.Both signals were sent digitally into Pro Tools.
Orlando, the engineer on that session, was initially frustrated thatthe Tampa's 20 dB pad couldn't be applied to the digital output,because he wanted to overdrive the signal and maximize the tubelikeeffects of the THA circuitry. As a work-around, he cranked the Tampa'sinput gain and squashed the signal with 20 dB of gain reduction throughthe optical compressor before it hit the digital output. This methodwas very effective for getting the tubelike sound he wanted, and itenabled the Tampa to compare favorably to the TubeWorks DI, with theadded advantage of clearer and slightly brighter highs.
M-Audio informed me that there is less headroom in the digitalsignal than the analog signal, which is why the pad isn't applied tothe digital output. The 20 dB gain-boost switch at the input is meantto be used in conjunction with the 20 dB pad at the output so that theinput gain can be driven hotter without overloading the analog output.This trick allowed me to reap the benefits of the THA's distortioneffect. Simply turning up the input gain and engaging the 20 dB boostto capture a quiet sound source yielded quite a bit of noise, so Ipreferred to use the 20 dB boost for its recommended overdrivefunction.
Surprisingly, the Tampa seemed to increase the low-end and midrangesustain on certain sound sources, such as toms, acoustic guitar, andthe dum of a dumbek, which added greatly to the character ofeach. The result was a reverblike blossoming effect, which I suspect isthe THA circuit enhancing the decay of the lower frequencies. However,M-Audio suggested that the Tampa is merely revealing the individualcharacteristics of the microphones. None of the other preamps exhibitedthis behavior.
While the preamp enhanced the dum on a dumbek, it alsoaltered the mid-frequencies, turning the bek into a bawk,which sounded great. Female vocals recorded with an AKG C 3000 Bthrough the Tampa sounded warm and detailed. In addition, the Tampabrought out some of the high harmonic content of a classical guitartrack, which the other preamps did not. This added depth to the soundof the instrument.
The Tampa exhibited more character than the understated RNP8380 andthe Mackie 1202-VLZ. Compared to the Grace 101, the Tampa wasn't quiteas detailed and clear in the high end, and the transients soundedsomewhat compressed dynamically. The Tampa sounded closer to the PeaveyVMP2 tube pre, but it wasn't quite as defined and crisp and was lessdynamic. The Universal Audio 2-610 sounded drier and clearer incomparison with the Tampa's fat, wet sound. The Tampa's A/D converterheld its own against the Digi 001's converter.
I also put the Tampa through some loudspeaker tests at MylesBoisen's Guerrilla Recording studio, and the results were revealing.Placing a Neumann KM 184 two feet in front of a single speaker, withbaffling behind the mic to absorb reflections, we played several tracksof vocal pop and instrumental music through the system. In someinstances, the Tampa's blossoming effect muddied up the mix. Inaddition, it diminished the airiness of a female vocal part slightlyand reduced the punch of a kick drum. Overall, however, the Tampasounded good.
The Tampa's dual optical-servo compressor is one of its majorassets. Compared with the Langevin Dual Vocal Combo (which is one of myfavorites for transparent optical limiting and preamp warmth), theTampa performed well, although it didn't sound quite as smooth. TheTampa wasn't particularly transparent in radical compressionsituations, but it maintained clarity and didn't have the woolly soundyou might expect.
Although it's not an application that's mentioned in the manual, Ialso used the Tampa as a standalone compressor to fatten up a vocal ina mix by giving it an overdriven, tubelike sound. The results werepleasing.
For my tastes, the Tampa's maximum attack time of 10 milliseconds ison the fast side, and 250 milliseconds as a minimum release time is abit slow. In addition, the lack of makeup gain in the compressor wasinconvenient. However, the Tampa's compressor is a useful feature thatsounds great overall.
The Tampa is a versatile preamp with a host of features you don'tusually find on preamps in its price range. It has plenty of character,with a decent amount of clarity in the high end and a fat-soundingmidrange and low end that sets it apart from other preamps. Inaddition, the THA feature is effective for adding tubelikecharacteristics. If you're looking to enhance your project studio witha quality preamp that has dynamics processing and digital converters,the Tampa is worth a visit.
AnalogInput(1)balanced/unbalanced ¼" TRS/XLR Neutrik combo connectorAnalogOutputs(1)balanced/unbalanced ¼" TRS; (1) XLRDigitalOutputs(1) S/PDIF; (1)AES/EBUInputImpedance Settings300ž,600ž, 1.2 kž, or 2.4 kžSamplingRates44.1, 48, 88.2,and 96 kHzWordLength24-bitGainRange34 dB (12 dB-46dB with +20 dB switch off)OutputImpedance600žFrequencyResponse20 Hz-40 kHz(±0.25 dB)Signal-to-Noise110dBAPowerConsumption12VACDimensions2U × 5.5"(D)Weight5lb.
GainReduction20 dBminimumThreshold-20 dBu to +20dBuCompressionRatio1.1:1 to10:1AttackTime1 ms-10msReleaseTime250 ms-5seconds
Karen Stackpoleoperates Stray Dog Recording Services andis Director of Studio Maintenance at Ex'pression Center for New Media.Thanks to Myles Boisen and Steve Orlando.