Product: Auna AV2 CD508 - integrated amplifier
Manufacturer: Auna - China
Approx. price: ±100€ (YMMV)
Test sample supplied by: Electronic Star - Italy
Reviewer: Lucio Cadeddu - TNT Italy
Published: December, 2012

Foreword

The T-Amps and all the Class-D amplifiers that invaded the market in recent years introduced a new deal in HiFi: their unbelievable quality/price ratio was simply revolutionary. However a common problem with these amps were their limited features: normally just one line input, no remote and, generally, low power output. For this reason I've always been waiting for an integrated amplifer, with reasonable power output, several line inputs, a remote and other useful features...still at an unbeatable price.

So here it comes, the Auna AV2 CD208 (yes, a weird name for an amplifier!): +50 watts per channel, four line level inputs (including a front panel minijack input (details below), one line output, a complete remote control, tone controls and balance...all for less than 100€! This interesting, made in China amplifier is easily available - at least here in Europe - thanks to Chal Tec an established source based in Germany.

Manufacturing & finish

The Auna AV2 CD508 is a traditional solid state integrated amplifier with three line inputs (RCA connectors in the rear) plus a minijack line input up front, ready to accept on the fly connections from iPods, MP3 players, smartphones etc. A line level output (via RCA's) is available on the rear panel, and this can be used either as "TAPE OUT" for recording purposes or as a way to connect a headphone amplifier (as the Auna doesn't offer a headphones output). Bass and treble tone controls and a balance knob complete the package. Everything can be remotely controlled by a handset that can also control a CD player from the same product line (more on this in a subsequent review).

The cabinet, a classical 43 cm rack-size, has a black anodized steel front fascia (3 mm thick) and uses a clever system of several bolts that keep the thin U-shaped cover firmly in place and prevent it from vibrating. Moreover, four, nicely crafted absorbing feet help minimizing the propagation of vibrations.

In the rear, besides the RCA connectors, there are the speakers binding posts, which accept bare wire, fork or banana clips, as well as the (non detachable) power supply cord and an ON/OFF switch. This switch serves to completely turn the unit off, as it otherwise remains in standy-by mode. The power switch on the front panel doesn't completely turn off the amplifier but toggles between "live" and standby modes. To exit from stand-by mode (red light) you switch this button or to press the power on key on the remote. The front light then switches from red to blue. Even the position of the volume control and of the selected input are indicated via a nice (but bright) blue leds. A relay connects the speakers after a couple of seconds of delay.

The remote allows you to control volume level, select inputs, switch the amp on/off or put the amp in MUTE mode. You can't remotely adjust tone controls or balance.

Let's take a look at the inside: it is a rather conventional circuit, with four power transistors installed on a large heatsink. The power supply section is of the switching kind, so no toroidal power transformer here! For this reason the weight of the unit remains below 3.5 kgs (7 lbs). This s NOT a Class D amplifier, the heatsink and the heat produced testify this is a standard Class AB circuit.

Tech specs

Not much is available in the online documentation or the owner's manual. The claimed power output is 125 watts, but it is unclear if this is the sum of both channels or not. Peak power is claimed to be 600 watts, which is pure nonsense. As this amplifier absorbs a maximum of 200 watts (as clearly indicated on the rear panel) and as it is a Class AB unit, a more realistic figure would be 50+50 watts per channel, RMS at 8 Ohms. Indeed, the standard efficiency for this kind of amplifiers is around 50-60%. For example, a Denon PMA 720AE absorbs 200 watts (max) and delivers 50 watts RMS per channel (@ 8 Ohm), so its efficiency is exactly 50%. Recommended speakers impedance range for the Auna is 8-16 Ohms. The unit measures a standard 42,5 x 8,5 x 26 cm (WxHxD).

Availability

This amplifier isn't hard to find. It can be purchased via the European distributor (Chal-Tec), the Italian distributor (Electronic Star) but is also available on Amazon.de (at just 70€!!!) or on various Ebay stores (just search for "Auna AV2").

Surprise surprise

It is impossible to avoid prejudices when a component offers so many things for so little money. Will its sound be acceptable? This Auna AV2 CD508 tries to prove your prejudices are...just prejudices! Its sound is full, with a powerful and surprisingly deep bass range, a clear mid range and a crystal clear high range. The tonal balance is open, bright and lively. Too good to be true, right? Well, when you try to forget its price tag, you can easily detect its shortcomings: especially during long listening sessions you sense something is missing: the frequency range is full but the harmonic structure of the sound is rather poor, as if the amp can't find time to spend on details. This is not a surprise, many low-cost amplifiers do just the same! The general feeling is that the sound possesses something artificial in it, almost electronic, not that natural character the real thing has. Actually, the main difference between an artificial and a natural sound is the harmonic content!
There's another aspect that becomes clear after long listening sessions: the sounds appears a bit slow, lazy, as if rhythm is lacking.

If you forget these limitations, which are common to many other low-cost amplifiers, you'll find the sound of this amplifier rather convincing: voices, for example, are reproduced in a very nice way, while I was expecting a complete disaster! So convincing that even a NAD 3120 (the best 3020 ever made) struggled a lot to prove it was a better amp :-)
I've devoted a whole paragraph to comparisons with other budget-class champions. Read on!
Single voices sound better than choirs, where traces of confusion can be detected quite easily. On soloists (male and females) the tonal balance is correct, without the harshness I was expecting from such a low cost unit.

The bass deserves a special note: it is powerful, deep and reasonably articulated. Certainly the consistent power output helps here. A good bass range is a key ingredient for the typical audiophile who will purchase an amplifier in this class. While it is neither extremely refined nor particularly smooth but, when I look at the price tag I'm persuaded to keep my mouth shut :-)

Dynamics

Provided you don't connect a killer load this Auna AV2 CD508 is a trusty and reliable performer: powerful enough to drive even low sensitivity speakers it sounds lively, though not always harmonically integrated. I've connected it to some very low sensitivity speakers like the Trenner & Friedl ART, the Koda/AAAVT BBL-N and the Norh 4.0 (all below 85 dB/w/m!) and it did his homework just fine. Especially in the bass, where its dynamic performance is rather good, better than in the mid and high ranges.

The mid range and the high range run out of steam early, with evident traces of compression, while the bass seems to be able to hold the line.
Obviously, you can't expect this amp sounds like a big amplifier, but it is entertaining enough to make you forget its diminutive price tag. It performs its best when dealing with simple musical programs it performs at its best but when there are too many instruments playing together at the same time dynamic performance suffers.
In the microdynamics department it isn't all that bad, but its harmonic limitations certainly don't help much.

3D Soundstage

It would be silly to expect an impressive performance here! While it can't create a huge soundstage at least the fundamentals are right: even those sounds outside the speakers area are reproduced with sufficient precision while the size of the stage is proportionally correct. Width, height and even depth are there, nothing to die for, but still acceptable. At the requested price this is a BIG surprise! There's also a certain scale of different horizontal planes. I wouldn't ask for more, to be honest!

Comparisons & quality/price considerations

Could I avoid direct comparisons with inexpensive Class D champions? Actually, to be honest, it is difficult to do a fair comparison because the price tag alone isn't sufficient: this Auna amplifier offers much more than those diminutive amplifiers: more inputs, more power...even a remote! For this reason I've decided to use a NAD 3120 to verify how champions of the past behave when compared to modern entry-level amplifiers. Of course, my beloved Trends TA10 will also be there, waiting to be connected and...fight :-)

First of all, when I compared the Auna to the NAD 3120. I was expecting a complete defeat, considering how good sounding the 3120 is but, surprise surprise, things don't always go as one expects. Yes, the NAD performs better in terms of PRaT, (Pace, Rhythm and Timing) plus it appears more natural and with a better focused 3D image. Even the tonal balance seems more neutral (just a little bit warm, as usual). On the other hand, the Auna performs better with voices and the whole sound appears bigger and more spacious. In the bass range the performance is surprisingly very close, unless you use killer loads. Here, the NAD takes the lead and wins hands down. Oh yes, before you ask, the NAD 3120 had been recapped recently.

Now it's time to hook up the little Trends TA 10. Embarassing, to say the least. Both the NAD and the Auna can't rival the refined sound of the Trends Audio Class D marvel. Its sound is easy, classy, refined, clean, harmonically rich with a virtual image that is simply huge, when compared to that of the other two contenders. Of course, given its power limitations, it can't sound as powerful as the Auna or the NAD but, within its limits, it is still a winner. The TA10 suggests you that high-end is closer than it should be, given its price. An amazing little amp!

Summarizing, the comparison tests have proved this Auna AV2 CD208 is a surprisingly good performer. While it is not in the same league as the other champions the distance is much less than I expected. Especially when compared to the 3120, one might wonder which one is better, especially in the mid range. The Trends TA 10.1, mean while, costs 180€ (and you need 215€ for the TA 10.2!), has just one line level input, almost 10 watts per channel and no remote! The Auna has 50 watts per channel, four line livel inputs, tone controls, a remote and...costs less than 100€!
As far as I know there's nothing on the market that can offer so much for so little money.

Some advice

The heatsink and the aeration grids of the cabinet help dissipate the heat produced by the amplifier but I'd recommend not placing other components on top of it. The stock feet and the whole cabinet help prevent vibrations but feel free to experiment with different damping tweaks (absorbing feet, tar sheets etc.). The power supply cord can't be replaced so if you wish to try a special mains cable you need to open the unit and modify it.
Speakers matching: I've used speakers with impedance lower than 8 Ohm (even less than 4 Ohm) and the amp performed nicely, just showing traces of dynamic compression from time to time. It also begins to overheat, especially if you run it at full power. For this reason I'd avoid speakers with impedance lower than 8 Ohm nominal.
Finally, consider that this unit, even in stand-by mode, doesn't run completely cold, there's still some heat dissipation. For this reason I'd suggest switching it completely OFF via the on/off switch in the rear when not in use.

Complaints

Manufacturing & finish.
Don't get me wrong but it is rather embarrassing for me to complain about an amplifier which offers so much for just 100€! It is well made, works flawlessly...and sounds rather good too! Anyway, since I'm here to complain, here we go:

• The blue leds are too bright, though not as bright as some I've seen on certain high-end gear!
• The central "null" positions of the tone and balance controls aren't immediately clear.
• I'd have preferred a tone bypass switch.
• The speakers binding posts are too close to the RCA inputs.
• There's no headphone output (though there's a useful LINE OUT)

Conclusion

Few years ago it was impossible to imagine an amplifier with so many things and features at a such modest price. In my opinion this is one of the best amps for anyone wishing to build a good HiFi system for peanuts. Also, it could be an acceptable solution for anyone trying to set up a secondary system with some audiophile ambition.
If you're looking for a powerful, reliable, solid and easy to use amplifier this one should score high in your wishlist. An amazing and surprising experience!

© Copyright 2012 Lucio Cadeddu - direttore@tnt-audio.com - www.tnt-audio.com