牌子：Tube Technology : Unisis Signature
介绍：The Unisis Signature is a vast improvement over it's predecessor.
It features a new improved preamplifier, high current driver stage, uprated power supply and best of all a superb new output transformer which has been in development for the last two years.
Output power: 35 watts RMS into 8 ohms
nominal speaker load: 8 ohms
rated power bandwidth: 12Hz-58Hz @ 35W-1dB
原价：MSRP $5,449.95
成色：８．５成新．
新机４万多．
el84每声道４支 ，ecc83/12ax7 一支，３5w．用的是ei的管．
解析力高细节丰富，声音细腻力水又够，音乐味浓密度及其空气感一流
台湾烧友的搭配＇
LINN Karik + Numeric,
Meridean 518 DSP,
"Tube Technology"
Prophet + Unisis,
Linn Kairn+AURA PA200 x2
Dynaudio Contour 1.3MK2
theres not many Tube Technology around, so i never mension about it in
topics, i like the sound of it, but "Unisis power 30w+30w" to drive my 1.3MK2 is a bit hard. i need one more to make it as MONO block. it sound better now, i change the prophet pre (Telefunken 2xECC81 2x ECC82), Unisis Power (8x JJ-EL84, 2x Telefunken ECC81). it actually improve the sound. any place sell in Tube Tech in TW?
新机４万多．
el84每声道４支 ，ecc83/12ax7 一支，３5w．用的是ei的管．
解析力高细节丰富，声音细腻力水又够，音乐味浓密度及其空气感一流
国外介绍：
Tube Technology Unisis Signature Integrated Amplifier
A tube integrated amplifier can and should be a beautiful thing for the space- challenged or budget-conscious audiophile. These elegant one-box solutions eliminate the potential of an impedance mismatch between preamp and amp, and obviate the angst and expense of investing in an additional pair of interconnects. Nowadays, virtually all well-known makers of tube electronics proffer integrated models. I think this is a noble thing -- it is unlikely to make any of these firms rich. Rather, I suspect that tube integrateds are often fruits borne of technology trickled down from more ambitious designs; we consumers stand to benefit from the inherent value that they can represent.
How does one go about choosing an integrated amp from the myriad offerings? If one is downsizing to a piece from the same manufacturer, one might anticipate a similar "house" sound. More often, the move to a tube integrated represents an opportunity to expand one’s sonic horizons.
An obvious place to start comparing is the choice of output tube -- the
different types tend to have different sonic traits. Then there are the
output stages: single-ended vs. push-pull, class-A vs. class-AB, triode vs. ultralinear operation. While these features may allow the audiophile to develop a hazy sense of an amp’s overall sound and performance, purchasing one based solely on these criteria can be folly. The quality and build of the power supplies and output transformers also influence the sound, as will the selection of passive parts such as capacitors and resistors. However, these features are less often specified, and even when they are, the names and numbers would mean little to most of us who do not build amps. But the implementation of all of these parts into a circuit design is where magic can occur, and where a designer’s talents are most challenged.
Ideally, you should audition the amp with your speakers in your room.
Unfortunately, this is often not possible, especially in light of the sheer
number of models and the shift of the shopping paradigm toward the Internet and used markets. Manufacturers’ information, demos at dealers (if you plan to buy from one), and presumably unbiased reviews, whether "professional" or anecdotal, may be your only buying guides.
In a recent writeup, I waxed enthusiastic about the Unison Research S6
integrated amplifier. Although a good number of tube separates and several solid-state integrateds have graced my systems over the past 30-odd years, the S6 is the first tube integrated I’ve owned. It was on this background that I was presented with the Tube Technology Unisis Signature integrated amplifier.
Tube Technology, based in Wales, UK, has been building audio electronics since 1988. More recently they have entered the digital fray with the development of a well-regarded CD player, the Fusion CD64. The Unisis Signature ($5200 USD) is a direct descendant of the Unisis, an EL84-powered integrated amp that was one of the company’s earliest efforts. For the Signature edition, the preamplifier and driver stages were improved, and a new output transformer developed.
The amp’s 35Wpc of output is derived from two pairs of Russian Reflektor EL84
tubes per channel, driven in a push-pull fashion and operating in class-AB, ultralinear mode. (The output tubes are also labeled "6n14n," the ns printed in Cyrillic.) A pair of 12AX7s enclosed within the chassis work as the preamplification tubes, and two exposed 12AT7s serve in the driver stage. An optional phono stage (add $200), not included in my sample, adds a second pair of 12AX7s and is said to accommodate cartridges with outputs of at least 0.8mV. The Unisis Signature accepts five single-ended, line-level inputs; those equipped with the phono stage take four. A tae loop and preamp output are provided; power delivery, optimized for a load of 6-8 ohms, is by way of a single pair of speaker binding posts per channel. The amp is powered up by a rotary knob on the front panel; no remote control is available.
My sample arrived with all of its tubes in situ. The Unisis uses a "fixed-
bias
system" -- Tube Technology claims that tube bias need be adjusted only when
replacing the output tubes with new ones. Should this happen, or should you
wish to experiment with other EL84s, you must use a proprietary bias meter
from Tube Technology. The biasing procedure itself seems straightforward; the
pots are easily accessed from the top plate of the chassis.
The Unisis occupies a small footprint 14" wide by 9" deep and weighs about 35
pounds. The shiny, reflective surfaces of its classic, somewhat "retro"
appearance brought out the primal audiophile in me -- I found the generous
amounts of chrome finish appealing without being garish. The build quality,
at
least from the exterior, appears to be more than acceptable, as the 10-year
transferable warranty attests.
I installed the Unisis Signature in my 14’ x 22’ x 9’ basement listening
room. The system was fronted by the venerable Sony SCD-1 SACD/CD player. The
even more venerable Cardas Hexlink 5s served as interconnects and speaker
cables. I listened mostly to the Sonus Faber Guarneri Homage speakers, as
well
as others as noted below. To make comparisons, at various times I inserted
the
Unison Research S6 integrated, used through its 8-ohm outputs.
Listening
I started off with Norah Jones’ Come Away With Me [Blue Note 32088 2]. Okay,
please stifle the groans. I’m aware that many of us have been overexposed to
this disc, but despite having used this music for some particularly tedious
cable auditioning a short while back, I never seem to tire of Jones’ sultry
voice or the mellow riffs of her Handsome Band. Through the Unisis, this
music
was presented in a clear, cohesive manner with no part of the frequency
spectrum lacking or overemphasized. Her voice was reproduced naturally, with
none of the sense of edginess that some setups bring out. A back-of-the-hall
perspective was provided, the image size being smaller and placed farther
back
between the speakers than I’m accustomed to. Imaging was sharply focused and
precisely localized. But while everything sounded nice, I found myself fast-
forwarding track after track rather than being ensnared in this music, as is
the norm. Could the local critic who dubbed Jones "Snorah" in a review of her
summer concert have been right after all?
In went the Unison S6. Immediately, the Handsome Band sounded more
dimensional
and Jones came to life, her voice taking on considerably more body and
texture. Her phrasing became more tangible, and the fragility of her voice
on "The Nearness of You" yielded an emotional connection to the music that
was
sorely missing with the Unisis Signature in the chain.
I listened to Schubert’s Octet, performed by the Academy Chamber Ensemble
[Philips 416 497-2]. This work -- scored for clarinet, horn, bassoon, two
violins, viola, cello, and double bass -- presents a rich palette of tonal
colors that sounded relatively washed out through the Unisis. The horn and
woodwinds were a bit pallid, and "bloom" was attenuated. The Allegro vivace’
s
rhythmic dynamics sounded fine at first, but only after I’d reinstalled the
Unison S6 could I appreciate how engaged the musicians were in playing this
music with each other, as opposed to simply going through the motions. Listen
to the start of the last movement, which features tremulous strings building
to crescendos. The sense of foreboding this motif invokes -- the kind of
stuff
a superior amp should convey -- is much better brought out by the Unison.
Pace and rhythm are somewhat abstruse audiophile concepts. Another war-horse,
Dave Brubeck’s Take Five [Columbia CK 65122], continues to captivate in
large
part because of its unique rhythmic structures based on unusual time
signatures. Nowhere is this more apparent than on "Everybody’s Jumpin’,"
whose tempo moves like a roller-coaster. Listen to the repetitive piano
chords
near the beginning of the piece and see if you can feel how Brubeck varies
his
intensity of attack to reinforce the rhythm. Listen to the last few seconds
of
the tune and see if you can feel the quartet playing to a frenzied climax.
With the Unisis in the chain, I had to try too hard to appreciate this.
Combine that with the barren sound of Paul Desmond’s alto sax and a less-
impactful sense of Joe Morello’s drum thwacks and cymbal crashes, and the
presentation was pedestrian. In a good setup, one shouldn’t have to listen
analytically to appreciate good pace and rhythm. Rather, these attributes
make
themselves apparent to the subconscious, and manifest by foot-tapping and
goosebumps when the occasion presents itself.
I listened to a variety of other material, and it became obvious that I had
serious issues with the Unisis Signature. I considered that the Tube
Technology device might have some bizarre incompatibility with the Guarneri
Homages, which in general perform quite well with a variety of amplifier
types. So I hooked the Unisis up to a pair of Wilson Audio Sophias. The
Guarneris are said to present a nominal load of 8 ohms, dipping down to
around
6 ohms, and are 88dB efficient; the Sophias present a fairly stable 4-ohm
load
and are 86dB efficient. The Wilsons were perhaps not the ideal match for the
Unisis’ output transformer, but I normally use the speakers with 50Wpc push-
pull tube monoblocks and feel that I lack for little.
The Unisis did make music through the Sophias, including acceptable control
of
their woofers, but duplicated the shortcomings that were apparent with the
Sonus Fabers. The most egregious were the lacks of midrange body and
presence,
but blunted microdynamic shading, limited macrodynamics, and a subtle sense
of
restrained pace and rhythm all added up to a generally ho-hum impression. The
Unisis seemed to do best with both speakers when playing amplified music,
though particularly with the Sophias. I put on the likes of Stevie Ray
Vaughan
and Keb’ Mo’ and enjoyed the tunes, forgetting for the moment about such
minutiae as air and bloom -- and, I suppose, these qualities are less
important to the enjoyment of this type of music. Sure, when powered by the
Unison S6, this music became more dynamic and intense -- but it also had a
more "in your face" quality that may or may not appeal, depending on your
musical sensibilities.
I wanted to try the Unisis on some high-efficiency speakers. I had no horns
in
my closet, but I did have a pair of 91dB-efficient B&W DM 302s, sweet-
sounding
bookshelf monitors acquired a few years back at a closeout price too good to
pass up. It quickly became evident that the Unisis was most at home driving
the B&Ws. The sound opened up and the music becoming more lively and tuneful,
especially pop and blues tracks. Despite this, however, Norah Jones remained
ever so soporific, the Academy Chamber Ensemble still moved along in
perfunctory fashion, and Brubeck and his buddies sounded as if they were
thinking about the next night’s gig.
The Unisis Signature didn’t sound bad. It was clean and neutral, with no
trace of hardness. It struck me as offering a somewhat anachronistic sound
that would mate very nicely with the original Harbeth HL Monitors, a pair of
which I owned and loved years ago. Its polite, spare presentation would
complement highly efficient, "colored" speakers, which are less commonplace
today. On my present speakers, its sound simply lacked the flesh that should
accompany the bones; as such, it consistently failed to draw me into the
kinds
of music I enjoy.
I reckon that judicious substitution of both the small-signal tubes and the
stock Russian power tubes with other brands might improve but would probably
not transform the Tube Technology’s sound. The difference in sound between
the Unison S6 and the Unisis Signature could probably be partly explained by
the inherent qualities of the output tubes -- despite the amps’ identical
power ratings, the EL34’s meatier, more powerful-sounding midrange simply
overwhelms that of the little EL84. Tube Technology does make EL34-based
power
amps; it would be interesting to hear them.
Conclusion
Audio enthusiasts are living in fortuitous times. New makers of tube
electronics offering innovative and high-value products seem to materialize
daily. Couple this with ongoing efforts from the established manufacturers,
and we have a vital and highly competitive marketplace in which to explore
the
integrated tube amplifier.
Still, at a list price of $5200, the Tube Technology Unisis Signature cannot
be considered inexpensive. The option of a built-in phono stage is a welcome
and uncommon feature for an integrated amplifier in this price class, but
partly due to current exchange rates that are unfavorable to the US dollar,
the value of the Unisis Signature relative to its peers must be questioned.
