Aragon 4004 mkII Review

December 17, 2011 in Amplifiers, Reviews


Do you need an amplifier that’ll drive the heck out of your speakers? Say hello to the 4004 mkII from Aragon. The 4004 mkII is powerful stereo amplifier delivering 200w into 8 Ω and 400w into t4 Ω. It was built by Aragon in early 1990’s, and designed by legendary designer Dan D’Agostino formerly of Krell, currently of Dan D’Agostino Master Audio Systems.

In 2001, Mondial Designs Ltd. parent company of Aragon and Acurus was purchased by Klipsch. Klipsch continued development of the Aragon and Acurus lines until 2004 when it ceased production and closed both businesses. Then, in 2008, following four years of inactivity, Aragon and Acurus were sold again, this time to Indy Audio Labs headed by two former Klipsch electronics engineers Rick Santiago and Ted Moore.

Since the purchase Indy Audio Labs has been on a mission to revive the popular brands. Aragon now has two new designs; the Iridiam 400w monoblock and the 8008 mkIII. Both designs continue the iconic v-shaped groove of original 2002, 4004 and 8008 amplifiers—the groove serves as a heat sink as well as a design element. No word on when Aragon’s amplifiers are shipping, but according to their website, Acurus is currently shipping their A-2000 series of amplifiers so I expect Aragon to be shipping in the near future. See their website for details ( I’ve always liked Aragon’s house sound and hope the new units sound as good as the old ones.

Although the 4004 mkII is not in production anymore they nonetheless can be found on the used market at places like and A key feature of the Aragon 4004 mkII and one that sets it apart from similar amplifiers is that it’s DC coupled.  With DC coupling there are no reactive components like capacitors, inductors, transformers, and others in the signal path and as a result the frequency response is quite flat all the way down to DC (0 Hz). Other advantages of this design include: simple circuits with a minimum numbers of components, excellent bass response and uniform frequency response up to high frequencies. Another benefit of having simple circuits with reduced parts is that DC coupled amplifiers hold up well over time.


Direct Coupled, Dual Mono Design, 1 Ω Stable


INPUT: L/R RCA OUTPUT: Standard Binding Posts POWER: Detachable IEC MISC: Fuse


POWER OUPUT: 200w/2 @ 8 Ω, 400w/2 @ 4 Ω THD: 0.05% for 8 Ω loads S/N RATIO: 110dB A Weighted FREQUENCY RESPONSE: 20Hz-20kHz INPUT SENSITIVITY: 150 mV for 1-watt output INPUT IMPEDANCE: 22 kohms POWER CONSUMPTION: 1500-watts max DIMENSIONS: 6.75”H x 19”W x 14.75”D WEIGHT: 76lbs

The 4004 mkII gets right a lot of what makes music so enjoyable; great dynamic range, good P.R.A.T and deep, tight bass. Bass through the 4004 mkII comes across effortlessly, excerpting total control over drivers keeping the pace fast and music snappy. The 4004 mkII’s power also gives it excellent dynamic range with ability to play loudly and clearly without compression; I was able to easily pick out different instruments while playing music at heightened listening levels.

The amplifier isn’t all beast and no beauty though; it operates in Class-A for about the 10-15 watts giving it an extended top end, evoking a good sense of space and realism. I got a good sense of this spaciousness on track 3 “Didn’t I” from Rebekka Bakken’s album Is That You? [Fontana Int’l]. The sustain from the saxophone on this track is great. Through 4004 mkII, I was able to close my eyes and follow the air as it moved through the passages of the saxophone as the musician played. With lesser amplifiers this information would still be present, but flatly presented in one dimension, the 4004 mkII lends just the right amount of body to the track.

The resolving power of 4004 mkII was better than average but not extraordinary. It pointed at the subtle musical minutia within a song rather than grabbing them and bringing them to the fore, however music was still enjoyable without being able to see all the way into it. This is highlighted on the track “Romance is Dead” from Paloma Faith’s Do You Want the Truth or Something Beautiful? [Epic] album. The track contains subtle musical details that dance around in the background, but the 4004 mkII is at a loss to fully flesh them out. It is an error of omission, rather than commission as we say and makes it easier to deal with because there is inner detail there, just not as prominent as with some amplifiers.

What We Liked:

  • Endless Power: “There’s no replacement for displacement.” The 4004 mkII can drive any loudspeaker you can throw at it. With 400w into 4 Ω it supremely controls drivers resulting in excellent and effortless bass impact. Less powerful amplifiers don’t have the dynamic range to realistically convey the full scale of full range music.
  • Extended Top End: The treble range is extended and airy without being etched or raspy. The 4004 mkII is snappy which lends to the amplifiers sense of speed and on quiet passages one can hear subtle spatial cues.
  • Excellent Build Quality: The 4004 mkII is a dual mono design with two toroidal transformers stacked on top of each other inside the chassis to the left. The faceplate is ¼ inch thick and the sheet metal is of heavier gauge than usual giving the 4004 mkII a solid, no frills feel.
  • Unique Design: The v-shaped groove cut into the top of the 4004 mkII is unique in all of audio. It serves as a heat sink, and is also a part of the design which makes it instantly recognizable to audiophiles. It also gives an ordinarily plain black box some pizzazz!

What We Didn’t Like:

  • Efficiency: At maximum power the 4004 mkII sucks down 1500 watts. Ouch.
  • Heat: It gets hot to the touch quickly.
  • Lacks Top Flight Transparency: The amplifier doesn’t pull out the inner most details.
  • Glare at Extreme Volume: In certain systems, when pushed really hard the amplifier can become too bright.



Our Verdict:

Sadly, our Aragon 4004 mkII review comes to an end, but it was a wholly enjoyable experience. Much like my Benchmark DAC1 HDR, the 4004 mkII plays it straight with the audio signal showing only a modest preference for treble which at times can become a bit bright. The mid-range isn’t lush or sweet so audiophiles, who prefer such a sound might want to pair the 4004 mkII with tubes or warmer sounding components to smooth out the top end just a bit.

The 4004 mkII is built to last and has a unique, easily identifiable design that continues to make a statement today. The 4004 mkII isn’t without its faults however; it lacks top flight transparency and it doesn’t flesh out and uncover the most delicate layers of music as good as other amplifiers I’ve heard. I can’t say how these omissions will affect you, but for me the 4004 mkII gets enough things right that I’m happy to overlook it’s omissions in exchange for huge power reserves, great dynamic range, and excellent bass drive. In the end, the 4004 mkII is an “easy read,” it sounds great, has solid build quality and is uniquely designed. It’s a pleasure to listen to and own.

HiFi Scorecard
More neutral than warm with an airy top end.
Great dynamic range able to play loudly without congestion.
Music was crisp and focused without sounding shrill or etched.
Quick with great timing.
Music was nicely layered, however amplifier was unable to uncover the deepest inner details.
Bass was deep and tight.
HiFi Verdict

Author and Associated Equipment
Thomas Turner
Speakers- PBN Audio Pennywise, Ohm Walsh 5
Amplifier- Aragon 4004 mkIIDigital Processor- Benchmark DAC1 HDR
Sources- Squeezebox Touch, PS3
Cables- DH Labs Silver Sonic, MIT EXp2, Signal Cable MagicPower Cord
Accessories- Homebrew x2 Isobases, Ikea Lack Audio Rack

Manufacturer Contact

Indy Audio Labs
5225 Exploration Drive
Indianapolis, Indiana 46241
tel: (866) 559-5113
fax: (866) 719-8516