This review page is supported in part by the sponsors whose ad banners are displayed below |
|
|
|
|
It's an integrated amplifier without DAC. In turn Ayre have their highly regarded QB9 external USB DAC. The AX-5 has very clean lines and its enclosure is made of thick aluminium plates. Although it is possible to identify design elements unique to this U.S. manufacturer such as specific mills or the shape of its solid knobs, one might as well point to the aforementioned Bladelius as the design's godfather. The front panel is a very thick machined aluminium block with large blue alphanumeric LED display, two knobs and two buttons. The knobs are used to select inputs and control volume. They are not marked with a volume scale or input names because they only serve as encoders. Selected input and volume level are indicated on the display instead. Using both knobs and the two buttons also navigates the menu and plenty of options starting with a list of input names including a custom one through input gain levels, home-theater bypass assignation, defeating the tape out and factory reset. The two buttons are illuminated, red for left, green for right. The latter functions as mute and controls the low-power consumption mode. That's similar to standby but only shuts down the output stage whilst leaving the preamp live. This shorten warm up and allows for using the still active tape out, say for a headphone amp (the input selector remains operational). The left button activates the tape outputs.
|
|
The device runs fully balanced topology with zero negative feedback. Therefore the most important outputs are the four XLR. Two RCA inputs look very solid yet their signal is first converted to balanced before hitting the input stage. The speaker terminals are excellent and come from Cardas like almost all other connectors on this amplifier. Only the XLRs are Swiss Neutriks. The speaker terminals allows for perfectly even clamping of spade connectors but bananas are not really welcome. According to the brochure a large part of the preamp section trickled down from the top KX-R. As soon as we look inside this shows in a beautiful Shallco selector used as volume control sporting a stepper motor and toothed gear belts exactly as in the flagship preamplifier. Apart from Ayre a similar solution though not as sophisticated was once used in the Model 5 amplifier by Avantgarde Acoustic [and Steve McCormack's mini preamp whose dual-mono controls used a slip clutch to double as balance control – Ed].
|
|
The switch in question has silver contacts and controls an ultra-precise low-noise resistor ladder located on the main circuit board. Ayre explains that their solution differs from more common implementations because it actually controls gain rather than attenuates the input signal. CEC, B.MC. and PS Audio use similar circuits which can also be found in higher-end mixing consoles. Ayre's system allows for 46 different settings in 1.5dB increments. Their solution is called VGT for variable gain technology.
|
|
Before we arrive at the volume control, the signal passes through the input selector. All input connectors are soldered onto small PCBs mounted vertically behind the rear panel. We see high-quality resistors (Ayre claims to have those developed in house), integrated FET switches and relays. If I had not consulted the materials, I would have said that the latter switch the signal. Apparently however they are used for permanent activation (or deactivation) of inputs as the company says that the input selector on the front panel selects inputs via FET selectors. The power stage mounts on large PCBs with gold traces. Unlike most other designs, these PCBs sit horizontally and hence the bolted-on heat sinks too mount horizontally. I do not know from the output transistors used. Ayre only informs us that this is a newly developed output stage called Diamond. What its novelty is we unfortunately aren't told.
|
|
The power supply looks beautifully executed too. Its foundation is very large classic EI power transformer. Power is supplied from the IEC socket via a high-quality (a rarity!) power switch and a coil which acts as power filter. The rest of the power supply mounts on a large board near the front panel. Among the components there are ten large filter caps from Cornell Dubilier and discrete voltage regulators for the preamp and driver stage. There are separate secondary windings for each channel's pre and power sections. The whole circuit is controlled by a microprocessor located on a small PCB near the front panel as the real brains of the unit.
|
|
The AX-5 looks exceptionally solid. Its level matches Accuphase but sports much better passive components and an even superior enclosure. Operation is fairy tale like. Also the remote control, which can be additionally used to switch off the display made a very good impression. It has large, easy-to-use buttons and nice illumination. The manual is very well written and of value in itself. The AX-5 is a machine in which everything seems to have been thoroughly thought through from its looks to the mechanical and electrical design, ancillary information and promotional materials to functionality. It's a beautiful example of no-frills high end without treating audiophiles like nitwits who only deserve a black box with one input and one output. For me the sound always is most important yet it's only one of the parts which make up a complete product. Ayre seems to understand that perfectly.
|
|
Specifications (according to the manufacturer)
RMS output power: 125/250W (8/4Ω)
Gain: 26dB
Output impedance (RCA / XLR): 1MΩ/2MΩ
Frequency response: DC - 250kHz
Power consumption (low-current/normal mode at idle): 48-230W
Dimensions (WxHxD): 440x480x120mm
Weight: 18kg |
|
opinia @ highfidelity.pl
|
|
|
|
|