Continuous power output:
250 watts RMS x 5, 20 Hz - 20 kHz, 8 Ω, all channels driven
400 watts RMS x 5, 20 Hz - 20 kHz, 4 Ω, all channels driven
Current capacity:
60 amperes peak per channel
Power bandwidth:
5 Hz - 100 kHz, +0/-3 dB at 1 watt
Total harmonic distortion:
< 0.2 % at full power
IM distortion: balanced 16 V rms
< 0.04 %
Slew rate:
> 130 V/µsecond
Dynamic headroom:
> 1.5 dB
Interchannel crosstalk:
> 78 dB at 1 kHz;
> 63 dB at 20 kHz
Input sensitivity:
1 V for 28.28 V, THX Reference Lev
Input impedance:
47 k Ω unbalanced; 94 k Ω balanced
S/N ratio:
112 dB, input shorted, IHF A-weighted
Damping factor:
> 1100 at 20 Hz
Voltage:
110V - 120V
Dimensions:
17-1/2" w x 7-5/8" h x 20" d, 7" h without feet
Net weight: 80 lb.
HomeTheaterReview.com
When it comes to high-performance, high-value power amplifiers, few do it better than
Parasound. The A51, which is part of Parasound's Halo line of cost-no-object products
designed in tandem with audio legend John Curl, has benchmark levels of performance,
yet costs a reasonable $4,500. Cost no object, huh? If every manufacturer built
sub-$5,000 cost-no-object products, the audiophile landscape would be vastly different.
Audioholics, October 2004
"The A 21 and A 51 amplifiers are both loaded with usable features above and
beyond most other amplifiers in today’s market." "The Parasound A 51 is
more than capable of driving any speaker load in even the most demanding home
theater systems." "The linearity of this amplifier is excellent at any power
level it is operating in, and its freedom from audible noise and distortion
makes it a true winner!" "The Parasound Halo A 21 and A 51 are top rate
amplifiers at a great value. Parasound seems to have attended to every aspect
of their design including the excellent build quality internally and externally
matched with great looks." Overall Rating: 5/5 Stars - Ken Stein and Steve
Dellasala
Home Cinema Choice (UK), October 2004
"The processor (C 1) offers enveloping surround sound processing, and the power
amplifier is muscular. It has a hint of warmth, but nothing that suggests
overhang, and the treble is unusually refined." "Indeed, I’d rate the A
51 as one of the most transparent power amplifiers in its class. It has genuine
power and authority, and delivers the kind of visceral kick that makes action
films swing along with panache." Five Stars - Alvin Gold
Revue Du Son & Du Home Cinema (France), March 2004
4 Stars
Stereophile Guide to Home Theater, March 2004
AAA Recommended Component - "I expected the A 51 to sound good. What I wasn't
prepared for was how good it sounded right out of the box. Its midrange was
totally seductive, its soundstaging and imaging abilities in the same league as
some of the best gear I've ever heard at any price."
Video (Germany), January
2004
"Mit souveräner Kraft und perfekter Harmonie führt die edle
Vor-/Endstufen-Kombi von Parasound direkt ins akustische Nirvana."
"With precise force and perfect harmony the noble preamp/amplifier combination from Parasound takes you directly to acoustic Nirvana." - Jürgen Schröder
Home Theater Buyers Guide, 2004
Featured component in Stepping Up Your System article. "Sky is the limit"
system.
Image Home Entertainment (Germany), November 2003
"...als echtes Überraschungspaket muss übrigens die
Fünfkanal-Endstufe gleten: Sie begeistert mit durchweg audiophiler
Klangqualität, gepaart mit unerbittlicher Power..." "...läutet der
Parasound C 1 eine ganz neue Generation von AV-Controllern ein..."
"...Feinheiten im Setup zeugen von Liebe zum Detail und enormer
Surround-Erfahrung..." "...Fazit: Hier waren zweifellos Könner am Werk..."
"...das Teamwork mit der A 51 befördert den C 1 in die klanglich erste
Riege..." "...der vom legendären Audio-Enwickler John Curl gezeichneten
Endstufe..." "...diese eng beschriebene Dokument ist perfekt gemacht, leicht
verständlich, liefert obendrein jede Menge Hintergrunderklärungen,
beschreibt das Gerät absolute vollständig und kann sogar mit
Internet-Hinweisen, Stichwortverzeichnis sowie ausführlichen Grafiken
aufwarten. Kompliment!" - Roland Kraft
"...the output stage with 5 channels must be considered as a real surprise-package: it enthuses with audiophile sound-quality without exception, joined by inexorable power..." "... the Parasound C 1 rings in a totally new generation of AV controllers..." "...refinements in the setup show the love for details and an enormous know-how for surround..." "...to sum it up: here doubtlessly experts were at work..." "... the teamwork with the A 51 promotes the C 1 to the A-grade squad in sound..." "... the output stage, drawn by legendary audio-developer John Curl..." "... this document in narrow letters is made perfectly, easy to understand, supplies furthermore a lot of background information, describes the set absolutely utterly and even offers internet-links, index and ample graphics. Congratulations!" - Roland Kraft
Stereophile Guide to Home Theater, October 2003
"If that 2-channel test drive had me thinking about buying the A 51, the
multichannel experience made me want to slap down my Visa card." "With music,
the A 51 radiated sweetness and light. With action films, it rained thunder and
lightning. There aren't many amplifiers that can so effortlessly cover both
ends of the sonic spectrum." "Beautifully designed and skillfully executed,
Parasound's Halo A 51 is all the amp anyone could need..." - Barry Willis
Widescreen Review, September 2003
"From the outset, I have to say that the Parasound A 51 multichannel amplifier
delivered impressively clean, effortless, detailed sound." "The Parasound Halo
A 51 multichannel amplifier, with its top-notch performance for movies and
music, deserves a very strong recommendation for anyone serious about quality
home theatre and surround music sound." - Perry Sun
T 3 (UK), September 2003
"The A 51 has so much grunt, grip and grace, you have to restrain yourself from
cranking up the volume until the walls start to ripple Matrix style."
"Its high price pitches it against formidable opposition, but the C 1/A 51
pairing more than holds its own, with a combination of massive power, killer
dynamics, fine transparency and user flexibility." T 3 Five Star Gold Award -
David Vivian
AudioVision (Germany), August 2003
"Parasound hat mit der Kombination C 1/A 51 eine echte Alternative zu den
Boliden von Lexicon und Tag McLaren geschaffen..." "Insgesamt also eine
fantastische Vorstellun." - Michael Nothnagel
Hi-Fi Choice (UK), July 2003
"Robust engineering rather than radical technology sees the THX Ultra
2-specified A 51 power amplifier through the day." "...the Parasound duet (C
1/A 51) allows the most substantial loudspeakers to melt from the scene."
"...rest assured that the performance of the C 1 and A 51 is as flexible and
impressive as you could hope for." Editor's Choice - Paul Miller
Son & Image (Canada), June 2003
DVD Etc., May 2003
"The bass extension is simply wonderful: copious, deep, taut, and rhythmic."
"The experience is so strong, that I found myself in musical nirvana..." "It is
a superlative performer in the $4,000, multi-channel amp category..." Rating 98
- Manoj Motwani, M.D.
c't Kino Daheim - special (Germany), April 2003
"Ein nochmals souveräneres, präziseres Klangbild mit unglaublichem
Bass und fantastischer Räumlichkeit" - Ulrich von Löhneysen
"And once again more sovereign (confident), more exact sound characteristic, with unbelievable bass and fantastic accommodation" - Ulrich von Löhneysen
What Hi-Fi (Russia), April 2003
"All sounds - from leaves rustling and rain, to rifles and a train's roar - are
reproduced very plausibly, without any tint or digital "dirt" from compressed
audio formats such as Dolby Digital. Soundtracks sound excellent, regardless of
genre. Voices of actors, their emotions - all sound very plausible, giving true
pleasure to any film fan. Special sound effects so loved by mystery and
thriller creators are magnificent. During 'The Call' the viewer remains
literally chained to the armchair. Creaks, leaves rustling, steps - all so
realistic that it forces even people with nerves of steel to shudder. In a
word, an outstanding set. Listen to it - you will not regret."