The Acoustic Signature Tango Phono Preamplifier
|The Acoustic Signature Tango Phono Preamplifier|
10 May 2002
Moving Magnet/Moving Coil phono preamplifier
Gain: MM = 48 db MC = 64 dB
Capacitive Loading: Selectable from 50 pF to 350 pF in 50 pF steps
Resistive Loading: Selectable at 10, 100, 1000 and 47,000 ohms
Additional special values available on request
Outboard power supply
Detachable AC cord (not included)
Size: approximately 5"W × 5"D × 3"H (main phono section)
Jerry Raskin's Needle Doctor
419 14th Avenue SE
Minneapolis, MN 55414
Peak High End
Weinbergstr. 27 D 71229 Leonberg
The Tango phono preamplifier is Acoustic Signature's first electronic product to be available in the US. Quite taken with the performance of their both their Final Tool and Samba turntables, I was naturally eager to hear the new Tango. Its $599 price places it at the point where phono stages are more likely to become permanent additions to systems rather than purely budget-directed stopgaps. While there are excellent, less expensive phono stages available, they tend to offer limited flexibility in loading options and may be dedicated to either moving magnet or moving coil inputs. Some of the less expensive phono preamps also tend to be more forgiving than strictly accurate sonically, their response tailored to supposedly match the humbler components with which they are likely to be matched.
The Tango includes both MM and MC cartridge preamplification and offers considerable loading flexibility to optimize cartridge performance. A series of dip switches located on the Tango's back panel makes selection easy: bravo to Acoustic Signature for allowing access to these without requiring entry into the Tango's innards. Unusual for moving magnet loading, the Tango offers 7 different capacitance settings, starting at 50 and then rising in 50 picofarad steps. The moving coil amplification offers 4 different load impedances: 10, 100, 1000 and 47,000 ohms. Gain provided is 48 dB for MM and 64 dB for moving coil.
The Tango is constructed from Acoustic Signature's now signature aluminum alloy. A long umbilical cord separates the phono stage from the fairly hefty outboard power supply. An IEC detachable power cord (not supplied) provides AC to the power supply. There is no on/off switch, but a green LED glows when the Tango is on.
One of the difficulties of auditioning outboard phono preamps is the necessity for an additional set of interconnects to connect it to the line preamplifier. Another sonic variable is thus introduced. I tried 8 different interconnects in auditioning the Tango: Radio Shack's gold RCA-plugged cables, the ubiquitous gray freebies, Kimber PBJ, Sumiko Premiere Catalyst, Origin Live's Ultra and Reference, Analysis Plus Copper, and van den Hul The First. Not surprisingly, the Tango's sound differed with each interconnect used. Thankfully, the Tango was not neurotic in demanding that only a particular interconnect be used to show its merits, but its resolution is high enough that one should avoid choking its output by using a cheesy interconnect. I eventually used the Origin Live Reference in most of my listening because its $200 price is a reasonable match to the Tango's, and because it offers an excellent balance of resolution, timbre, dynamics, rhythm, phrasing and soundstaging.
Acoustic Signature does not include a detachable AC cord so I was forced to experiment with various AC cords, further complicating the task of trying to grasp the Tango's inherent abilities. To simplify the number of variables, I used a plain, standard grade AC cord for most of my listening. A series of experiments with various pythonesque aftermarket AC cords brought diffferences in sonics, but not always musical improvements. The best of these brought an addition in clarity, with the sound more clearly emerging from its background, along with greater silence between notes.
Common to European phono stages, the Tango includes a non-defeatable infrasonic bass filter in its design. Since bass reflex woofer-loading is the dominant speaker design of the contemporary market, and since reflex loading does not damp woofer excursions below the in-box resonant frequency, filtering the output from record warps and other subsonic garbage is a definite plus.
The Tango utilizes op-amps in its design. I have no prejudice for or against any kind of design, preferring instead to listen to the results rather than tainting my perception with presuppositions.
Two to three days of playing were necessary for the Tango to find its voice after I first plugged it in, and with no on/off switch, once broken-in, it stays broken-in. MC load impedances should match most cartridges on the market, although I couldn't exactly match the van den Hul Frog's lowest recommended loading of 600 ohm requirement and used 1000 ohms instead. The lowest output MC cartridge I used - the Talisman Boron at .26 mV - had ample amplification with the 64 dB of moving coil gain provided.
The 48 dB of gain in the MM mode is high enough to allow easy use with higher output MC cartridges, and although higher than is strictly necessary for the outputs of MM's like the Grados, Shures, Regas, Clearaudios and Goldrings, the Tango never overloaded or turned harsh with the higher output levels of these cartridges. Older preamps, with higher amounts of line stage gain than contemporary practice, might find volume settings to be very low at normal listening levels. This might be a problem if volume tracking of the preamp is non-linear at lower volume settings and the preamp offers no balance control. Modern integrated amps and line stage preamps, with their typically lower amounts of gain, might even benefit from the oomph of the additional MM gain.
I listened to 6 different turntables, 4 different arms and 7 different cartridges, along with the 8 interconnects mentioned, in an attempt to suss out the Tango's acoustic signature. I also experimented with isolation products, including Navcom Silencers, Vibrapods, Aurios MIB's and a 3-D Seismic Sink. Line preamps, amps and speakers were isolated on Aurios PRO Media Isolation Bearings.
Unlike some phono stages on the market, the Tango does not deliberately soft focus the musical signal. One of analog LP's noted strengths is an organic and believable rendition of tonality, and some phono preamps, hoping to meet the listener's expectations of sweetness and softness in analog playback, overdo this aspect. The Tango, within the limits of its ultimate resolution, lets the quality of the signal speak for itself. Although from the standpoint of high-end, a $600 phono section is often dismissed as merely budget or entry level, there is no electrical reason why a phono preamp in this price range shouldn't produce the complete signal and I applaud Acoustic Signature for not artificially dumbing it down.
Overall, the Tango featured good clarity and detail across the frequency range without artificially softened highs or dimmed presence. Upper midrange was without added sibilance and the presence region of pianos and violins didn't clang or shriek. Laudibly, this was achieved not by a dip in response in this crucial region (where our hearing is the most acute), but by resolving and sorting the information. Passing this acid test of my bête noire of audio playback was very encouraging, as errors in this range tend to kill listening satisfaction quickly and is fatal to classical music. Bass was tight and rhythmically articulate with lively dynamics.
The Tango revealed the differing sonic signatures of the various tables I auditioned. Linns sounded like Linns, and the Tango's match with Acoustic Signature's Samba turntable reinforced their respective sonic strengths. Differences in arms and cartridges were also readily apparent, though not at the expense of becoming analytic in the negative sense. Nor were the differences spotlit.
While there was nothing mind-blowing about any individual aspects of the Tango's performance, its balance in all the important areas of performance was laudable. Frequency response, dynamics, clarity, rhythmic propulsion and creation of the stereo illusion were all very good. The Tango never got in the way of the music. It did not favor classical over jazz or rock, nor did it work well with only certain forms of music. This is essential for any audio component and particularly pertinent in less expensive products. It can be frustrating when a component only complements certain types of music, and stultifying when one's listening tastes are eclectic. Too often components show good performance in most areas only to fail miserably in one crucial one, leading to the disappointing "close, but no cigar" syndrome.
Playing with capacitive loading on MM cartridges was instructive and useful, although the only cartridge I had on hand with a known history of needing careful matching was the Shure V-15 V xMR. The current production version is far less persnickety than the older V-15 models. The proper capacitance, added to the capacitance of the tonearm leads, serves to linearize the high frequency performance of moving magnet cartridges and the fine gradations of the Tango's settings made it easy to get it just right.
The amplifying section of the Tango is smallish, rigid and light in weight, and did not show cosmic improvements in sound quality when used with various isolation devices, most of which are designed to deal with bass pollution in the environment. The Tango's low mass ensured that it wouldn't be vibrating sympathetically with low-frequency environmental contamination. For most of my auditioning I used either no isolation at all or the Vibrapods. I noticed bigger improvements in isolating the power supply than the phono stage proper.
How much should an uncompromised, completely satisfying, phono preamp cost? Given my predilection for high-performance, reasonably priced products, I wish I could say that one can simply plop down $600 and never look back. In general, though, I've found that sub-$600 products usually offer only minor improvements, sometimes merely lateral steps, and at times steps backwards, compared to the phono stages included in the better complete preamps of yore, all of which were designed and purchased with the quality of the phono section as the prime desideratum. This is particularly true as one descends the price range of new products. Those who have remained loyal to the LP format are likely to have already purchased high performance phono preamplification and those new to vinyl or owning preamp designs which exclude a phono stage face a quandary: buy a new outboard phono preamp or shop for an older, used high performance preamp. Factor in the hidden cost of a high quality interconnect to the purchase price of a new phono section (and in the Tango's case perhaps a higher performance AC cord) and we're at the price of used ex-state-of-the-art preamps.
The circa $600 price point in new phono preamps keeps getting denser as more new products are introduced. The Tango offers very competitive performance. I preferred its additional clarity, for example, to the Lehmann Black Cube, which, in both old and new version, is a benchmark in this price category. The Tango's balance of strengths allows the gist of the music to come through and I never found myself musically frustrated by any aspect of its performance. Quite the contrary: the experience of the old "chills down the neck" - Gordon Holt's test of musical realism and, coincidentally, poet A. E. Housman's criterion for the effect of true poetry, occurred again and again in my listening tests. Its ultimate abilities are limited, however (what component's isn't?), including somewhat curtailed large dynamic swings, some shortcomings in resolution and sonic realism, and in ultimate musical expression. None of these limitations capsize the listening experience and, realistically, are only likely to be perceived in direct comparison to higher resolution designs. A strong recommendation then, especially for those whose tastes and systems allow for a non soft-focus presentation.
Don't forget to bookmark us! (CTRL-SHFT-D)