Manufacturer: Avantgarde Acoustic Lautsprechersysteme GmbH
he bottom panel of the electronics module mounted on the Zero 1 PRO speaker’s rear baffle features an identification plate. In addition to information about the place of manufacturing – here Avantgarde’s new large factory in Reichenbach (Lautertal), Germany – we also find a cleverly given serial number. The speakers that came to me after initial break-in at the manufacturer and then by the distributor were labeled as "ZERO.0008". This made them one of the first Zero 1 PRO pairs that had ever been assembled.
We ought to start as the manufacturer does in the information brochure, which is “from the beginning”. The Zero 1 PRO is a horn-loaded, three-way active speaker system. Each of the two horn driver units is driven by a separate 50-watt X50 amplifier, and the woofer by a powerful 400-watt Class D amplifier. The midrange and treble units operate in pure class A, with zero negative feedback and fed from the power supply taken directly from the XA power amp. Power to them is so often filtered, and the control system has stabilized power supply. The sensitivity of the midrange and tweeter drivers is high - as with horns - and reaches 104dB. It's just that we are familiar with that from many other designs. Yet even here we can point to certain characteristics that are unique to this product. First of all, its size.
Speaking in Munich with Armin Krauss, whom you should easily recognize (each year during the Audio Show in Warsaw he’s the Avantgarde presenter who likes to play Rammstein at a concert-level volume), I couldn’t help but notice that describing the new project he spent most of the time to explain an innovative formula of the whole system. We are quite familiar, as he said, with active speakers as such – just have a look at the D’appo from the Polish manufacturer Sveda Audio. Active speakers are fed by a line-level signal straight from a preamplifier or sound source, which is then crossed over in an active crossover network and amplified separately for each driver unit. The Zero 1 PRO is different as it accepts a digital signal that is first processed in that form by D/A converters before going to analog amplifiers.
We know, therefore, that the Zero 1 PRO is an active three-way speaker with a digital crossover. It stands to reason that the signal used to feed them should also be digital. And so it is. The whole electronic circuit, including amplifiers, is housed in an aluminum cast enclosure mounted to the rear baffle and covered with a nice grille. From below we can plug in a USB or Toslink cable, two digital S/PDIF cables and one AES/EBU – in other words nearly all existing standards. If we want to use WLAN transmission, we need to connect to the Toslink input a suitable receiver, such as AirPort Express.
Technology is the key here, as this is what defines the Zero 1 PRO. Equally important, however, is its user friendliness, which is respecting the time and frustration of people who want to use these speakers for listening to music. The rule is that the less time we spend on connecting and calibrating the system, the more we can spend on listening. And music is always the winner. The speakers from the company headed by Holger Fromme are one of the most technically complex audio systems available and they are at the same time the easiest to use. They are essentially maintenance free. You pay money for that but nothing in life is free.
Albums used during auditions
The Avantgarde Acoustic loudspeakers communicate with each other via a radio link. They only need to be hooked up to the mains with the digital input of the master loudspeaker connected to the music signal (e.g. via AirPort Express). That's it.
It’s all true. Although manufacturers of advanced digital equipment write about “user-friendly”, “smooth” and “nice” operation of their devices, this is almost always more wishful thinking than reality. In practice, the number of steps required to get the sound from an audio device having anything to do with computers and digital sources seems to be growing exponentially with their capabilities. Thus, quite unexpectedly, CD and SACD players turn into a symbol of true ease of use and reliability. Even a PhD degree in computer science does not guarantee you will get the sound straight after unpacking the unit, and any setup change will almost certainly make you repeat the installation process. That is one of the reasons why I think of computer as a valuable but bothersome sound source. It has no “play” button and all too often I have to go to extra lengths to force any sound out of it at all. For me it’s a waste of time.
We will immediately know we’re listening to Avantgarde speakers. The Zero 1 PRO sound in the way that is hard to mistake for anything else. Their sound is extremely dynamic. The German manufacturer has accustomed us to that and it hardly makes much of an impression on anyone. It’s simply the way it is and that’s it. The problem is to switch back to classic designs which, by contrast, seem slow and sluggish. Only magnetostatic and some electrostatic speakers combine speed and tonality in the way that the Zero 1 PRO, and in further perspective all speaker designs from Reichenbach, do. The longer I listened to the reviewed speakers the better I profiled my musical choices, and the more distinct was the similarity of my “playlist” to what I usually listen to on my HiFiMAN HE-6 magnetostatic headphones.
What stood out first were classical music recordings. Almost all the speakers I know have a problem with them. Or many problems at once. Some more pronounced, other better disguised, but in general almost all tend to get lost and do not show the detail and the whole equally well at the same time, usually focusing on one or the other.
The Zero 1 PRO, just like the HiFiMAN headphones, are capable of both simultaneously. Their sound is detailed and coherent at the same time, thus showing the whole music event. If we want to, we focus our attention on any instrument, artist or their group, and if don’t, we can “move away” and listen to the whole orchestra. It came intensely into play in the Prologue from Also Sprach Zarathustra. The opening low rumble was not merging together into one because it was conveyed as consisting of a variety of small components. Yet they were only audible when I was drawing my attention to this or that. I remember Damian Lipinski, who is responsible for Savage’s CD remasters, talk how he was surprised that each sound (instrument) on this musician’s recordings came from layering several and sometimes even dozen tracks together. A simple snare was composed of a dozen separate strokes. But it is only audible on a good audio system, i.e. the sound is rich and multi-layered. On a poor system it’s just a strange sounding snare (see HERE). The Avantgarde coped very well with it. The sound on Also… was quiet, like the double basses closing this part, but when the orchestra played forte everything developed immediately and sounded very loud and extremely fast. This level of dynamics and selectivity cannot be faked, and only stage audio systems and large studio (active) speakers are capable of sounding that way. No wonder Armin often plays Rammstein.
But it is not only dynamics and excellent selectivity that will surprise us in such an unusual combination. They do not exist just for themselves but are only a base for coherence. The company literature talks much about nearly perfect phase characteristics of the D/A converters and the digital crossovers are excellent in this respect, at least in theory. I must say I have probably not heard any digitally filtered speakers that sounded like the Avantgarde. It’s not a perfect design, nor aspiring to be one for all I know. But we get here all the things that the manufacturer promises. And the time coherence I mention translates into an incredible tangible sound.
The latter is felt differently than I am used to. The sound is projected by the Zero 1 PRO on the speaker line and in front of it, in an incredibly vivid and tangible way. The soundstage depth is only slightly marked. That is partly why everything seems to be fleshy. But that is only the beginning. The real ride begins when we realize that everything can be heard here. A conundrum, isn’t it? After all, selectivity implies something just like that and there seems nothing to talk about. It only seems so, though. As a matter of fact, selectivity describes how the elements that are sonically different, such as instruments, human voices, acoustic characteristics, and even various parts of larger instruments, are separated from each other, and how exactly the difference between them is shown. What I would like to say in the context of the reviewed speakers is something else still, not even associated with resolution, which is not better than in passive speakers from the same price range. I think of something that gives us vividness without rounding the attack, without withdrawing treble and without minimizing the amount of detail. Each of them leads to a vivid presentation, but each one also irreparably distorts the sound. The Zero 1 PRO sound “immediate”, if I may say so. Speed is one thing, but the other is a sort of an orderly universe, a here-and-now sound without looking for sounds getting slowly out of the background, while on the other hand without cowering before sonic urgency, sharpness and aggressive attack. Here everything fits together; the sounds, instruments and planes do not fight each other but have their inner “communication” that is invisible yet synchronizing everything. I have not heard that in any other speakers from this manufacturer. Actually, I rarely ever hear such a thing.
The speakers under review are similar to the Uno Fino, one of the better sounding speakers from Avantgarde – in my opinion, of course – in dynamics, speed, frequency range, selectivity and soundstage. On the other hand, they resemble my all-time favorite but no longer manufactured Uno Picco with their understanding of the presentation as a coherent structure, a grid with finish superimposed on top. And what I wrote earlier is simply unique to them. However, one needs to be aware that they are one of the less expensive speakers in this manufacturer’s product lineup. If we take into account that we get here a pair of three-way speakers with – say – active bass (as in other AA speakers), together with two stereo Class A amplifiers, a stereo (that’s how it can be viewed – it converts stereo signal) DAC, and active crossover to boot, then there is no use expecting them to sound at the same level as more expensive speakers with active bass that still need a power amplifier, preamplifier and DAC. What is the difference between such systems? First of all, resolution. Secondly, bass definition. And thirdly – soundstage. What is surprising, however, is not what we just said – that happens to be absolutely normal. It is so and that’s it. The real surprise is the degree of similarity of the Zero 1 PRO to flagship designs from this manufacturer. I think first of all about tonality.
Horn speakers cannot be mistaken for any others. Their strength lies in the immediacy of energy transmission, which is perceived as more accurately rendered textures, better dynamics and generally superior differentiation. Their resolution is not particularly impressive; selectivity comes out much better. The Numero uno, however, are all about the midrange presentation. If classic speakers sounded similar, I would say that their upper midrange is stronger than what is below. Here it is interpreted as part of a larger package. It’s a bit like ‘temperature’ and the so-called ‘perceptible temperature’. While the thermometer shows a certain reading in winter, the temperature we actually perceive can be a few or even dozen degrees lower, depending on wind chill and air humidity. In classical speakers, emphasizing the upper midrange is perceived unambiguously as something wrong, very wrong! The Avantgarde show that range in a way that is like opening the window. We get sounds along with reverb and accompanying acoustics, immediate and instant. I think it’s more about speed rather than emphasizing the midrange. It seems stronger to us because we are used to a different presentation. The top end is pretty sweet and detailed, although it does not draw our attention unless an instrument happens to venture into this region or the producer plays with counter-phase. Then it immediately jumps into our field of vision. The bass is strong, low and fleshy. Its low extension is amazing, especially with such a small cabinet capacity. It is here that the wonders of digital processing are best heard. However, the upper bass is not as saturated and full as in classic speakers. It is better defined than the bottom end but also a little more distant. Such karma. And technology limitations.
Writing about the sound of these speakers is lots of fun. Yet I wouldn’t be quite fair if I said that that’s what’s most important about them. Everything is in its place, the speakers play with panache and perfectly scale the sound to the listening room size. Auditioned in Munich in a 50-meter hall they played with a greater volume and forward momentum than at my room, placed about 2.5 meters from the listening position. I found no problems with the bass. Everything was simply slightly smaller than in the large hall. In this respect, they are phenomenal. They also have something about them that makes us listen to music with interest, waiting for what’s coming next – a rather important feature in audio, isn’t it? However, in my opinion, the strength of this design lies in its form combined with the ease of use and only then supported by the sound. Their outer form is truly amazing. The speakers remind me the monolith from 2001: A Space Odyssey by Stanley Kubrick (1968), and the curvature of the horns perfectly matches the rest of the cabinet shape. Connecting them to the audio system is piece of cake and everyone can do it. The Zero 1 PRO do not require any in-depth knowledge of electronic equipment to use them. It’s a world championship. There will be no sudden software “glitch” nor will we “lose” connection. The speakers resemble in that my ideal piece of audio gear, the CD player.
On the technical side, the Zero 1 PRO is a complex system that can, however, be broken up into relatively simple factors. These are much easier to describe. It is a three-way active speaker design. The 25mm tweeter and the 125 mm midrange driver are horn loaded to increase their sensitivity. The horn diameter of the former is 130 mm and of the latter is 400 mm. Their configuration is reversed, i.e. the tweeter horn is below the midrange horn. The woofer is loaded classically into a vented enclosure. The port is a gap on the rear baffle. The 300 mm woofer driver has a paper cone supported by stiff folds of impregnated fabric. The woofer is covered with a grille made of gray fabric stretched on a plastic, pretty stiff frame. The speakers are tilted back and the angle can be adjusted for their proper phase alignment. They ought to be positioned so that the tweeter radiates towards our ears.
The electronics is mounted on a large circuit board bolted to a solid, big, heavy cast, working as a heat sink. Its form resembles that of a car amplifier, only better built. Each speaker is equipped with one such module, but only one of them sports inputs connectors. We have at our disposal two electrical S/PDIF RCA inputs, Toslink optical input, USB input (16/44.1/48) and AES/EBU. In addition there is an Ethernet port. The latter, however, is not used to connect the speaker to the Internet (which more and more companies choose to do, thus having the option of remote equipment maintenance), but for alternative connection between the speakers. As the digital signal is fed to only one of them, it is transmitted wirelessly to the other. It can also be done in a traditional way, via Ethernet cable. A careful look will reveal a pair of balanced analog inputs. This option will be available very soon, allowing to connect the system to analog audio sources. Inside, there is a suitable place for mounting the board with A/D converter.
As it turns out, the electronics is mounted in a modular fashion using both manufacturer’s own “blocks” and components from Hypex Electronics BV. The digital signal is fed into the main board housing the digital receiver, USB-S/PDIF converter and FPGA unit that carries out the calculations. The USB receiver is the well-known TAS1020 chip capable of handling the signal up to 24-bit and 96 kHz. The fact that it is limited here to CD quality is due to design choices. The electrical inputs feature impedance matching and isolating transformers. After selecting the active input the signal first goes to the AKM4113 digital receiver and then to two AD1895 stereo frequency converters that convert any input signal to one that is accepted by the adjacent big FPGA chip. After processing, the signal is sent to a separate board with the actual digital-to-analog converter, a four-channel Burr Brown PCM4104. And only from there it gets to the two amplifier modules mounted on separate boards. The upper- and mid-range is handled by a classic Class A solid state amplifier. It is based on two medium-sized complementary transistor pairs per channel. The PCB sports excellent high-power Dale resistors, Wima, Elna and Nichicon capacitors – no money was spared. The bass is handled by an amplifier module from Hypex Electronics BV, the UcD400 in OEM version. The amplifier has its own switching power supply, also from Hypex. The other two amplifiers share a common switching power supply, with much more complex circuit. Due to its modular design, I can easily imagine a future system upgrade of any of its sections.
Technical Specification (according to the manufacturer)
- Turntable: AVID HIFI Acutus SP [Custom Version]
- Cartridges: Miyajima Laboratory KANSUI, review HERE | Miyajima Laboratory SHILABE, review HERE | Miyajima Laboratory ZERO (mono) | Denon DL-103SA, review HERE
- Phono stage: RCM Audio Sensor Prelude IC, review HERE
- Compact Disc Player: Ancient Audio AIR V-edition, review HERE
- Multiformat Player: Cambridge Audio Azur 752BD
- Line Preamplifier: Polaris III [Custom Version] + AC Regenerator, regular version review (in Polish) HERE
- Power amplifier: Soulution 710
- Integrated Amplifier: Leben CS300XS Custom Version, review HERE
- Stand mount Loudspeakers: Harbeth M40.1 Domestic, review HERE
- Stands for Harbeths: Acoustic Revive Custom Series Loudspeaker Stands
- Real-Sound Processor: SPEC RSP-101/GL
- Integrated Amplifier/Headphone amplifier: Leben CS300XS Custom Version, review HERE
- Headphones: HIFIMAN HE-6, review HERE | HIFIMAN HE-500, review HERE | HIFIMAN HE-300, review HERE | Sennheiser HD800 | AKG K701, review (in Polish) HERE | Ultrasone PROLine 2500, Beyerdynamic DT-990 Pro, version 600 - reviews (in Polish): HERE, HERE, HERE
- Headphone Stands: Klutz Design CanCans (x 3), review (in Polish) HERE
- Headphone Cables: Entreq Konstantin 2010/Sennheiser HD800/HIFIMAN HE-500, review HERE
- Interconnects: Acrolink Mexcel 7N-DA6300, review HERE | preamplifier-power amplifier: Acrolink 8N-A2080III Evo, review HERE
- Loudspeaker Cables: Tara Labs Omega Onyx, review (in Polish) HERE
- Interconnects: Acoustic Revive RCA-1.0PA | XLR-1.0PA II
- Loudspeaker Cables: Acoustic Revive SPC-PA
- Power Cables: Acrolink Mexcel 7N-PC9300, all system, review HERE
- Power Distributor: Acoustic Revive RTP-4eu Ultimate, review HERE
- Power Line: fuse – power cable Oyaide Tunami Nigo (6m) – wall sockets 3 x Furutech FT-SWS (R)
- Power Cables: Harmonix X-DC350M2R Improved-Version, review (in Polish) HERE | Oyaide GPX-R (x 4 ), review HERE
- Power Distributor: Oyaide MTS-4e, review HERE
- Portable Player: HIFIMAN HM-801
- USB Cables: Acoustic Revive USB-1.0SP (1 m) | Acoustic Revive USB-5.0PL (5 m), review HERE
- LAN Cables: Acoustic Revive LAN-1.0 PA (kable ) | RLI-1 (filtry), review HERE
- Router: Liksys WAG320N
- NAS: Synology DS410j/8 TB
- Stolik: SolidBase IV Custom, read HERE/all system
- Anti-vibration Platforms: Acoustic Revive RAF-48H, review HERE/digital sources | Pro Audio Bono [Custom Version]/headphone amplifier/integrated amplifier, review HERE | Acoustic Revive RST-38H/loudspeakers under review/stands for loudspeakers under review
- Anti-vibration Feets: Franc Audio Accessories Ceramic Disc/ CD Player/Ayon Polaris II Power Supply /products under review, review HERE | Finite Elemente CeraPuc/ products under review, review HERE | Audio Replas OPT-30HG-SC/PL HR Quartz, review HERE
- Anti-vibration accsories: Audio Replas CNS-7000SZ/power cable, review HERE
- Quartz Isolators: Acoustic Revive RIQ-5010/CP-4
- FM Radio: Tivoli Audio Model One