Ayre AX-5 Twenty

Ayre AX-5 Twenty Review

by Marc Heijligers, 11-08-2024

 

 

A wish fulfilled

Since childhood, music and audio have always been among my greatest interests. I owned a CD player since 1984, just two years after its introduction, at prices that were just affordable for a high school student. Over time, I gradually upgraded my speakers and amplifiers. In 1992-1993, I acquired an Audio Innovations Classic 25 Tube amplifier, which underwent numerous modifications, paired with an Audio Note E (DIY) loudspeaker, this setup brought quite some musical enjoyment.

 

In 2003, I embarked on a new DIY speaker project with some friends, to address the shortcomings of the Audio Note E speaker (congested with complex music, coloration). A new amplifier was needed because the new speakers had an efficiency of 85dB/W, compared to the 92dB/W of the Audio Note, and the impedance curve had more dips and peaks. This was too challenging for a ~10W triode-mode tube amp.

 

I appreciated the rich sound of zero-feedback tube equipment and was drawn to Ayre's design philosophy, which promotes zero-feedback balanced circuitry. By 2005, I owned a CX-7 and AX-7, later upgraded to the Evolution (and eMP) versions. I was always amazed at how effortlessly the AX-7 drove the speakers, giving the impression it had much more power than its specified 60 Watts (@ 8 Ω). The treble attack was somewhat muted and the bass was less tight compared to other amps (a topic I discussed at length with Charles Hansen from Ayre).

 

In 2022, I had the opportunity to buy an EX-8 Full demo amp at a good price. Comparing it to the AX-7 revealed a larger soundstage, more accurate projection, fuller bass, and brighter treble. Overall, the EX-8 offered more authority, dynamics, and control. While the AX-7 had a slightly nasal and polite sound, it also had a certain "magic”. However, the benefits of the EX-8 outweighed these aspects, so I acquired it and later upgraded to the EX-8 2.0.

 

A few weeks ago, I saw a second-hand AX-5 Twenty for sale for a fair price. This amplifier, with its Variable Gain Transconductance, had always intrigued me and was high on my hypothetical wish list since it appeared in 2012. The seller was willing to demo the amplifier at my house, allowing me to audition it in my own environment. It took only a few seconds of listening to decide that I wanted to buy it. Let me explain why.

 

 

 

System Description

My current system consists of an Aurender N200 streamer, an Ayre QB-9 Twenty DAC, and the AX-5 Twenty (latest model with all the latests tweaks).

 

 

The speakers are DIY speakers, with a pretty flat frequency response (based on an-echoic measurements) and aligned phase response (hence the group delay of the units is the same, and all frequencies arrive at the same time to the listener, contributing to an holographic image). Impedance is amplifier friendly, never going below 5Ω.

 

 

 

 

First impressions

In May 2024, shortly after acquiring the AX-5, I had the opportunity to audition the AX-5 Twenty more extensively and with a wider variety of music, along with a friend.

 

In summary, this is the most organic, realistic, and lively amplifier I have ever heard. Its precision, articulation, texture and neutrality are amazing. This amplifier immerses you in the music, regardless of genre, recording quality, or volume. It consistently provides a strong “being there” experience that captivates and inspires.

 

When you are interested in an extensive decomposition of my experiences, read on. Every topic stands on its own, so arguments may be repeated.

 

• Tonal balance (timbre)
  The AX-5 Twenty has a timbre that feels authentic and natural. It maintains harmonic control and balance across bass, mid, and treble under all conditions. There is energy in every region, and no particular range stands out unnaturally as with many other amplifiers. There is no electronic haze, no exaggerated details, and no masking of details, resulting in a feeling of ultimate naturalness. This allows you to forget you are listening to electronic equipment and become fully absorbed and emotionally connected to the music. The amp does not exaggerate anomalies in certain frequency components of a recording; instead. This ensures the amp performs well even with less-than-ideal recordings.

 

• Bass (16-125 Hz)
  The amplifier sounds majestic, with a lot of grandeur, solid and powerful. The pace and rhythm are excellent, making the bass coherent with the rest of the frequency range and sufficiently dampened.
  Off Topic: There are many stories online about the higher output impedance of zero-feedback amplifiers resulting in less controlled bass. The effect of the 0,15Ω output impedance of the AX-5 is less than 10%, and will not be audible. See appendix 2 if you want more insights in this topic.

 

• Fundament (125-500 Hz) & Midrange (500-2000 Hz)
  The amplifier ensures that each instrument's and voice's fundamental and harmonic components are well-integrated, resulting in a coherent sound that is both full-bodied, and lifelike, avoiding an overly warm and mellow sound. It is a rich sound, which at the same time is not coloured at all.

 

• Presence (2000-4000 Hz)
  This is the region defining the articulation of voices and attacking energy of cymbals. Excessive emphasis in this range can result in harsh and fatiguing sound, while insufficient presence makes the music sound dull and muted. The AX-5 Twenty delivers ample energy in this specific segment without becoming overpowering. This significantly enhances the realism of voices and instruments, without inducing listener fatigue.

 

• Treble (4000-20000+ Hz)
  The treble is powerful yet refined, allowing instruments like for instance harpsichords to stand out subtly in a baroque orchestra, akin to real-life performances. It avoids sounding harsh, metallic, or overly magnified, which may initially impress but eventually becomes tiring. The treble is far from muted; recordings with significant sibilance on female voices sound fierce and clear without being rounded off.

 

• Dynamic range, Grip (scale)
  This amplifier operates without limits, effortlessly delivering without any compression or congestion. This capability remains consistent across all volume levels, showcasing the amp's absolute control. With energy consistently distributed across the whole frequency range, it maintains a balanced contrast between loud and quiet passages, allowing each to develop and decay naturally in the soundstage. An implicit indicator of its correct dynamic performance over the whole range, is its ability to facilitate conversation without requiring a reduction in volume, akin to the experience of live acoustic music.

 

• Attack & Decay (temporal development)
  The speed at which the amp can accelerate is very impressive. Such attack emerges from complete silence. Sound also decays into a black background without compromising brightness and details (it’s not disappearing and loosing details as with some mellow sounding amplifiers). What's particularly striking is the precision of the harmonic development. When for instance a string is plucked, the journey begins with the energetic release of the string, resonating from its fundamental area. This initial pluck sets the wooden front plate and the surrounding air into motion, resulting in a rich harmonic palette where the subtle nuances of the snare and wooden cabinet resonate alongside the primary tone. It can transition between notes with astonishing fluidity, capturing the dynamic nuances of the music with precision.

 

• Details, Texture, Resolution, “micro-dynamics” (fine details)
  What sets this amplifier apart is its exceptional ability to seamlessly integrate timbre, scale, dynamic development, and details throughout playback. Unlike many amplifiers that tend to exaggerate details, resulting in a constant haze that can become irritating over time, this amplifier maintains a perfect balance. This coherence is what truly brings the performance to life, making it feel realistic and deeply engaging, and drawing you into the music.

 

• Sound stage (sense of space, 3D)
  The AX-5 creates a deep and expansive holographic soundstage, characterised by air around the sound sources and multiple layers where the musical setting takes place, all while maintaining excellent imaging and separation. There are amplifiers that may project a deeper image, this is often achieved at the expense of an excess in the treble region. Upon careful listening, one may notice that the decay of sound in the depth of such amplifiers is limited to the upper frequency ranges, rather than the full frequency range. In contrast, the sense of space rendered by the AX-5 is impeccable, offering a balanced and natural representation of the music's spatial dimensions.

 

• Imaging & separation (pin-pointing)
  The AX-5 exhibits excellent pinpointing capabilities, ensuring that sources within the soundstage maintain a stable position and are accurately sized and delineated. Even in complex pieces, there is no tendency for the sound to smear or blur, allowing for precise localisation and separation of individual elements within the music.

 

• Long-term impressions
  After spending some months with this amplifier, my impressions remain unchanged. With every listening session, I continue to be amazed by the exceptional sound quality it delivers. Many friends, who now have also experienced the amp, share my sentiments—they've all been genuinely impressed.

 

 

Conclusion
Overall, each note is delivered with precision and clarity, allowing you to fully immerse yourself in the music, and to find yourself on the edge of your seat, exploring the different elements of the performance and uncovering the wide range of emotions and nuances that the artists are trying to convey. It's a reminder that there's so much more to music than just rhythm and melody; it's about emotion, expression, and the profound connection between the listener and the music.

 

 

 

Appendix 1: Comparison to the EX-8 2.0

 

 

The AX-5 Twenty outperforms in every aspect. It delivers a more organic sound, extracting richer textures without becoming “electronic”, while maintaining greater control, weight, and grandeur. The AX-5 excels in integrating timbre, dynamic development, and transparency, offering a beautifully cohesive experience. Vocals, violins, and pianos are articulated with a natural continuity, energetic drive, and harmonic richness that feels just right. While both amplifiers ramp up sound effectively, the AX-5’s attack is more precise, emerging from complete silence and decaying with grace. In contrast, the EX-8’s decay lacks the same depth, with a less black background. The AX-5 also creates a deeper and broader soundstage with more layers, enhancing imaging and separation without compromise. It feels like it has a proper cross-feed. With challenging music, I often find myself lowering the volume on the EX-8, but with the AX-5, I can comfortably increase it, even with demanding tracks. Both amplifiers provide a lush and warm midrange, but the AX-5 truly captivates with sources like voices due to its harmonic structure and timing of harmonics.

 

Does this make the EX-8 2.0 a disappointing amplifier? Not at all. It is a very good amplifier, the best I know for its price! I’ve compared it to many alternatives up to and above its price range, and it always came out as the best amplifier.

 

It reminds me of a previous experience that stands out in my mind; a visit to Peter van de Willenswaard with Guido Tent, around 1998. The reason for our visit was to listen to an Audio Note Ongaku amplifier that Peter had for service at his company, AudioMagic. At that time, the Ongaku was a €100,000 amplifier with a strong design philosophy regarding circuits and components. When we arrived, Peter’s push-pull pentode amplifier (a modified Philips HF309) was playing Stravinsky's "Sacre du Printemps”, on a pair of Audio Note E speakers. The sound was marvellous, captivating, and I was wondering “what could ever be improved”? When we played the same music through the Ongaku, a whole new world opened up. Compared to the previous setup, the sound was so “organic” and reached your soul so much deeper that it was almost a spiritual experience. Upfront, Guido warned me that after this session I wouldn't be able to listen to my own setup for weeks, and he was right.

 

This is exactly the experience I had with the AX-5 Twenty versus the EX-8 2.0. The latter is very good (best at its price range), but the AX-5 Twenty is a point of no return (but at more than twice the price).

 

 

Appendix 2: Terminology & Tech

 

Frequency range

The following table can serve as help for the terminology I use to describe certain frequency ranges

 

Output impedance

There are many stories online about the higher output impedance of zero-feedback amplifiers resulting in less controlled bass. The measured output impedance of the AX-5 Twenty is about 0.15Ω in the audible frequency range. Passive filtered loudspeakers typically have an inductor in series with the woofer; in my case, it's 4.7mH. At 35/50/100Hz, this inductor causes the woofer to see a series resistance of 0.75/1.5/3 Ω to the amplifier, in addition to the output impedance of the amp. This 0.15Ω output impedance has a 20/10/5% effect on the damping factor. I consider those values to be inaudible.

 

For the novice: see below the relationship between the speaker enclosure Q_TC (an indication of dampening), and the total series resistance that a woofer sees (amp + wiring + filter choke).

 

 

It show that a series resistance of 5Ω even doesn’t bring a speaker with Q_TC=0,5 (in my case) to a speaker with Q_TC=0,7 (also ignoring room reflections disrupting the impulse response even more)

 

 

So the 0,15Ω output resistance of the AX-5 is completely negligible.

 

 

 

Appendix 3: Music Auditioned

In the initial session, we have listened to the following tracks to review the amplifier (and enjoy the evening and music):

 

 

	Jordi Savall  -  Couperin: Le concert Royaux; Track 4: No. 1 - IV. Gavotte. Notes égales et coulées AliaVox AV 9840
	Susanne Abbuehl; The Gift; Track 3: If Bees Are Few ECM 2322
	Lukas Geniušas  -  Rachmaninov: Piano Sonata No. 1 & Preludes Op. 32 Track 1: Rachmaninov: I. Allegro moderato Alpha 997
	Michael Wollny  -  Nachtfahrten Track 14: Nachtfahrten ACT 9592-2
	Pink Floyd  -  The Wall CD2, Track 2: Is There Anybody Out There EMI CDS 746036 8
	Teodor Currentzis  -  Mahler: Symphony No. 6 Track 1: I. Allegro energico, ma non troppo Sony G010003865622Q
	Reinhard Goebel  -  Heinichen: Dresden Concerti CD 1, Track 1-2: Concerto In F, S 234 Archiv 437 549-2
	Sera Una Noche  -  Sera Una Noche Track 6: Nublando M•A recordings M052A
	Sera una Noche  -  Otra Noche Track 5: Golondrinas M•A recordings M092A
	Valery Gergiev  -  Tchaikovsky: The Nutcracker Track 13: Act 2: Character Dances: Russian Dance Track 14: Act 2: Character Dances: Dance Of The Reed Pipes Philips 462 114-2
	Teodor Currentzis  -  Tchaikovsky: Symphony No. 6 Track 4: IV. Finale. Adagio lamentoso Sony 88985404352
	Angus & Julia Stone  -  Down The Way Track 11: Draw Your Swords Discograph 3241882
	The Hot Sardines  -  Live At Joe's Pub Track 8: St. James Infirmary (Live) Hot Sardines 888295004237
	Youn Sun Nah  -  Same Girl CD2, Track 1-3: Bitter Ballad, Avec le Temps, Peace ACT 9024-2
	Tord Gustavsen  -  The Ground Track 5: Colours of Mercy ECM 1892
	Miles Davis  -  Kind of Blue (remaster) Track 3: Blue in Green Sony 01-064935-10
	Chet Baker  -  Chet Track 1: Alone Together Analogue Productions CAPJ 016
	Schuppanzigh Quartet  -  Ries: String Quartets Vol. 1 Track 5: WoO 10 - I. Allegro molto moderato CPO 777014-2
	Ella van Poucke; Caspar Vos  -  Rachmaninoff: Sonata for Cello and Piano Op. 19 Track 1: Sonata for Cello and Piano Op. 19: I. Lento - Allegro moderato Challenge Classics CC 72930
	Dudok Quartet Amsterdam  -  Solitude: Mendelssohn, Weinberg & Shostakovich Mendelssohn Track 2: Mendelssohn: String Quartet in F Minor, Op. 80: II. Allegro assai Resonus RES10215
	Kronos Quartet  -  Tan Dun: Ghost Opera Track 4: Act 4: Metal & Stone Nonesuch 7559-79445-2
	La Real Cámara   -  Boccherini: String Trios Op.14 Track 1: Boccherini: String Trio in F Major, Op. 14, No. 1, G. 95: I. Allegro Glossa GCD 920308
	Reinbert de Leeuw  -  Gubaidulina: Jetzt immer Schnee Track 3: Perception - Wir Philips 442 531-2
	David Zinman  -  Rimsky-Korsakov: Great Orchestral Works CD1, Track 12: Tale Of Tsar Saltan - Tsar's Farewell & Departure Philips 442605-2
	Philips  -  Compact Disc - Pure, perfect sound forever Various Tracks Philips 810 027-2 (this CD was in the box of the first generation of Philips CD players)
	Audio Physics  -  Sampler Track 2: Dean Peer - Mars Turtle Records TRSAS01
	Timothy Seelig  -  Rutter: Requiem; Five Anthems Track 11: Rutter: Requiem - Lux Aeterna Reference Recordings RR-57
	Eiji Oue  -  Mephisto Track 8: Saint-Saëns: Danse Macabre Reference Recordings RR-82CD
	Melanie De Biasio  -  No Deal Track 7: With All My Love PIAS Le Label 962.A023.022

 

 

 

 

Thanks for your in-depth review. My impressions of the Ayre gear are similar to yours. I have Ayre MX-R Twenty amps, KX-R Twenty preamp, and a QX-5 Twenty DAC with USB2 and Network2 boards. 
 

Wonderfully musical products!