line section for playing high resolution audio discs, compare to the really big guns, expensive separate high end multichannel analog line sections, which are dedicated to doing just this one task? So, as our further check, we not only compared the AVR300 (still in direct mode) to the straight wire bypass, but we also directly compared it to some of the finest, most expensive separate multichannel line sections (each of which could also be instantly compared to the straight wire bypass as a sonic reference standard).
Stunningly, the AVR300, in overall sonic performance, equaled or surpassed the finest, most expensive separate multichannel line sections we compared it to, yielding equal or better sound, and also coming closer to the sonic virtues audible from the reference ideal, the straight wire bypass. Most notably, the AVR300 actually surpassed all these other expensive line sections in what for many of us is the most important sonic parameter for a surround system: preserving, reproducing, and portraying rich spatial imaging information. As noted, the whole raison d'etre for a surround system is to reproduce and re-create a richly believable surround spatial image, so believable that you are aurally transported out of your small room and into the alternative venue of the recording. As we discussed extensively in an earlier review, the final frontier for surround systems is the reproduction of space itself, and the earlier Arcam products discussed in that review (the AV8 and DV27A) represented a significant advance over other surround processors and DVD players at the time, in this key sonic aspect. Well, the new AVR300, with the latest engineering advances from Arcam, represents a yet further advance in this most important sonic aspect. The AVR300 is in fact such a huge further advance that it not only trumps all other surround processors, but also trumps the finest, most expensive separate multichannel line sections, in this most important sonic ability, richly and accurately reproducing space itself.
Specifically, the AVR300 surpassed the separate dedicated multichannel analog line sections in reproducing a wide open, airy width dimension, and more precise localization, and a solid, tactile believability of images, between and beyond all loudspeaker locations. These are the spatial imaging parameters where the AVR300 was audibly virtually perfect in accurately mimicking the impossible reference ideal, the sound and spatial imaging audible via the straight wire bypass. In contrast, the expensive separate multichannel line sections made the spatial width sound more narrowly constricted and closed in, with less precise localization, and less tactile and believable portrayal of individual instruments, voices and sounds - as directly compared to both the AVR300 and also to the reference straight wire bypass. Then, even in the parameters of spatial imaging where we had heard a tiny loss in the AVR300, compared to the impossible ideal of the straight wire bypass, namely depth and ambience, the AVR300 still surpassed the sonic performance of the expensive separate multichannel line sections. These other high end line sections made the depth even flatter (more 2D), and reduced ambience even more, thereby making the portrayed spatial image sound more canned and closed in.
These sonic contrasts in spatial imaging were not huge, but they were easily noticeable, and the superiority of the AVR300 was easy to appreciate and enjoy. Those expensive separate multichannel analog line sections are very fine units, but the AVR300 proved to be even better in this crucial sonic aspect of spatial imaging. These are audio perfectionist comparisons we are making here, and some might say that it's insane to be applying this rarified level of sonic testing to what is merely an integrated receiver, and merely a $1999 complete receiver at that. But it's a testament to the sonic quality of the AVR300 that we have to take it to this rarified level of perfectionist testing to find its limits. And it's pleasantly shocking to find that, even when taken to these perfectionist levels of sonic evaluation, the AVR300 still wins compared to expensive perfectionist separates, especially in this crucial sonic aspect of spatial imaging.
The AVR300 also generally equaled the best sonic performances, by these expensive separate multichannel analog line sections, in most other sonic aspects. The AVR300 was actually slightly superior in other important sonic aspects like transparency, open airiness, and revelation of subtle inner detail. On the other hand, the AVR300's intrinsic sound has a slight personality of solid state sound, and just one of the other high end multichannel analog line sections did perform slightly better the AVR300 in this one sonic aspect, having a more neutral quality (halfway between solid state sound and tube sound) that was also closer to the neutral sound of the reference ideal straight wire bypass. Note though that the AVR300's intrinsic slight solid state quality can be easily ameliorated by an appropriate choice of power cord (as will be discussed below).
After the above thorough probing of a surround processor's sonic abilities as a multichannel analog line section, we move on to evaluating its sonic performance via its digital input. This is the mode you would want to employ for most input signals that are digitizable, which would include discs with compressed digital audio (film soundtracks), and perhaps also stereo CDs. The advantage of using the digital input is that the AVR300's signal processing capabilities (all of which are accomplished digitally) become available to you, whereas with the multichannel analog input you are constrained to the direct mode (evaluated above), which does not allow any conversion to digital (for fear of piracy) and hence does not allow any digital processing options. When employing the digital input, the audio signal still passes through the analog direct stages (volume control and output buffer stage) whose sonic quality was discussed above, and then in addition the signal also passes through two other key stages in a processor, the final D/A converter and the main signal processing chip set. For the latter, the AVR300 employs a massive DSP, which performs all signal manipulation, routing, and specialized surround processing. These added stages of course have the potential for introducing further sonic degradation in any processor, on top of the sonic degradation already noted for the analog direct mode (which in the case of the AVR300 is uniquely minimal, since its sonic performance in this analog direct mode was found to be nearly perfect).
We always evaluate the digital input mode in its basic form first, with just the digital signal routing and final D/A conversion added into the signal path, and without adding any special signal processing (for the various Dolby, DTS, etc. modes). We do this in order to determine the intrinsic sonic capability of the digital input at its basic best (later we evaluate the sonics of the added special processing executed for the various surround mode enhancements). In the AVR300, the single DSP performs both the task of special surround processing (for the various Dolby, DTS, etc. modes) and also the task of basic signal manipulation and routing. So we had to first determine which modes in the AVR300 engaged the most direct route through this DSP, with the least signal manipulation, in order to fairly evaluate this digital input signal path at its intrinsic best sonic capability.
How then did the AVR300 sonically perform on this digital input test? In a word, stunningly. So stunningly in fact that the AVR300 is the very first surround processor we've found that is sonically competitive with the very finest, most expensive separate components that you might find in a high end perfectionist system (such as premium outboard D/A converters, or the D/A converters found in premium disc players). Indeed, the Arcam AVR300's sonic performance here, via its digital input, can be so stunning that, when we directly compared the sound via the AVR300's analog direct input to the sound via its digital input, the sound via the digital input was even better, in some key sonic aspects (such as transparency).
Note that, when the AVR300 was in the analog direct mode evaluated above, it employed the perfectionist tactic of literally turning off the power to its digital signal circuitry, in order to optimize the analog sound by eliminating the interference from the digital circuits being turned on. But now, evaluated via its digital input, the AVR300 has turned on its digital circuitry, and furthermore is putting the signal through these digital stages (in addition to still putting the signal through the same final analog stages as were used in the analog direct mode). Yet in some key ways the AVR300 sounded even better now, via its digital input, than it had via its analog direct input. How could this be, when the signal now has to go through two additional major stages, the complex DSP and the D/A converter, which by definition can only corrupt and degrade the signal further?
The first part of the answer is that the AVR300's on-board D/A converter is so superb that it beats the sound of the D/A converter in most premium disc players, and equals the sound of the best outboard D/A converters. Thus it sounds better to omit the D/A stage in the premium disc player, and bring the signal out of the player and into the AVR300 in digital format, allowing the better sounding D/A converter in the AVR300 to perform this task. And, if you are a perfectionist into high end separates, note that it sounds just as good to use the AVR300's D/A converter as it does to use a premium outboard D/A converter and then route the signal into the AVR300's analog direct mode.
The second part of the answer is that the signal path through the AVR300's complex DSP (while engaging a minimum of processing) sounds so incredibly transparent and pure that, even when saddled with this additional complex DSP stage in the signal path, the AVR300's D/A conversion still sonically beats the D/A conversion in most premium disc players, thereby making the AVR300's digital input signal path surprisingly sound even better than its analog direct input path.
We know from an engineering point of view how complex DSPs are, and how easily their complexity can butcher sonic fidelity. And we have heard firsthand how the DSPs in other surround processors (even expensive high end ones) have literally butchered the sound, when placed in the signal path, as some of our recent reviews attest. So you can rest assured it is a classic understatement when we tell you that Arcam has achieved a superlative engineering triumph here, in getting the AVR300 to be so sonically superb, and indeed competitive with separate outboard D/A converters in perfectionist systems, even in spite of the signal being further handicapped by also going through the DSP, when it is digitally input.
The AVR300's superb intrinsic sound via its digital input is great news, since most of the program material fed into a surround system can be (or even must be) brought into a processor via the digital input. It's especially great news if you, like us, have a treasured library of music on stereo CD.
Why? With most other surround processors, given the inferior sound through their digital inputs, we have faced a three way dilemma in playing our library of CDs. For best absolute sonic fidelity, we had to bring their signal into the processor, the system's electrical focal point, in analog mode from a premium disc player or outboard D/A converter, so we could use the processor's analog direct mode. But this meant we could not employ the surround enhancement features of the processor. And virtually all two channel CDs can benefit greatly from surround enhancement, as we have discussed in previous reviews. To get the benefits of surround enhancement, we would have to ruin the signal's fidelity by putting it through the surround processor's inferior version of D/A conversion, by bringing the signal in digitally from the disc transport. Or, as a third choice, we could get some sonic benefits by employing the superior D/A conversion in the premium disc player or outboard processor, but then some of these benefits would be cancelled or offset by the usually worse degradation of having to go through the processor's A/D conversion as well as its D/A conversion. Not a pretty choice.
But now, thanks to the AVR300's superb sonics via its digital input and its superb D/A conversion, we can get the best of both worlds from our treasured library of CDs. For example, the latest CD masterings of early 1955 stereo recordings (e.g. Munch/Boston on RCA) have stunning sonic fidelity via the AVR300's digital input, fidelity which surpasses many of today's recordings. Then, using the AVR300's surround enhancement modes (e.g. Neo 6 Music), we are able to synthesize a 3D surround ambience field from these two channel recordings which actually sounds better and more believable than the surround ambience field from many of today's true surround recordings (even high resolution discs played via the AVR300's analog direct inputs). Now that's a real treat, and a really incredible achievement by the AVR300.
Just think about that. The AVR300 can give you, from your treasured library of music on two channel CDs, including recordings half a century old, a sound that can have better fidelity and a better surround field, than many of today's true surround recordings. Is this AVR300 something special, or what?
The next step in our standard processor evaluation procedure is to add yet another stage into the signal path, this time the processor's built-in A/D converter that is used to convert incoming analog signals to digital, for processing or surround enhancement. You would be employing this mode for doing surround processing on incoming two channel signals from external analog sources. Note that, when such two channel analog sources are plugged into the AVR300, you always have a choice of conveniently selecting (via the AVR300 main menu or front panel push button) the direct mode discussed first above, which engages only the AVR300 volume control and analog output buffer stage in the signal path (and even electrically turns off all digital processing, for even better sonic purity). Or you can disengage the AVR300 direct mode, in order to accomplish signal processing, which then activates and puts in the signal path the AVR300's digital circuitry, the DSP for signal processing, the D/A converter to generate the AVR300's line level analog output (which also drives the built-in power amplifier), and now also (for two channel analog input signals) the A/D converter to convert the incoming analog signal to digital for processing. In other words, simply switching the AVR300 from direct mode to non-direct mode, for a two channel analog input source, adds a heck of a lot of extra circuitry into the signal path.
How did the AVR300 sonically fare in this mode? Excellently, and again better than any other processor we have ever evaluated, regardless of price. All the sonic virtues of the input signal, as audible via the cruel straight wire bypass comparison, were preserved amazingly well by the AVR300, amazing considering how complex the signal path now was. Our only sonic comment was that all the sonic virtues did not sound quite as spectacular as they did via the AVR300's direct mode. That's a very mild sonic criticism, and is actually very high praise, in view of the fact that the signal was now undergoing two extra conversions (A/D and D/A), and was now in a more contaminated environment with the digital circuitry turned on, and was now going through the complex DSP circuitry. This means that you can confidently use the surround enhancement, signal processing powers of the AVR300, knowing that the basic sonic fidelity of your two channel analog sources is not being sonically compromised (as it is, to varying degrees, by other processors).
To sum up the AVR300's performance thus far as a surround processor, any and every signal path through the surround processor (analog direct, digital in, or analog non-direct) is intrinsically capable of superb sonic fidelity, better than we have heard from any other processor at any price, and even competitive with the finest perfectionist separate components.
The next evaluative step was obviously to add the AVR300's built-in 7 channel power amplifier section into the signal path, to probe its sonic performance. How did this power amplifier sound? Once again, we were pleasantly shocked and amazed at the AVR300's performance. It excels at all the important sonic virtues, including transparency, clean purity, wide bandwidth with easy coverage of both spectral extremes, an open and airy sound, and all aspects of spatial imaging.
The AVR300's power amplifier also has an amazing amount of dynamic punch (including very good bass impact and definition) - amazing for a 100 watt-per-channel amplifier, and especially amazing for a power amplifier that squeezes 7 of these 100 watt channels within a compact chassis that also houses a tuner and a complete surround processor that sets new sonic standards (not to mention the modest price of the whole package). Even though the power rating is merely 100 watts per channel, we found that we could play the amplifier quite loudly, and the sound remained wonderfully clear and pure, without the congestion that many other power amplifiers evince at high volume levels. This was especially rewarding with complex orchestral music, since the AVR300's superb clarity, purity, and absence of congestion, even at sustained high volume levels on complex music, let us hear into the orchestral ensemble, and let us hear the composer's complex orchestrations, better than most other separate high end multichannel power amplifiers, even those selling for many times the $1999 price that gets you not only the AVR300's on-board power amplifier but also the complete receiver.
Indeed, even if the AVR300 were only a basic multichannel power amplifier selling at its same $1999 price, we would pronounce it the best sounding, most capable multichannel basic power amplifier you can get anywhere near this $1999 price (and the overall sonic equal of even the best sounding multichannel power amplifiers at any price, with subtle pros and cons). The fact that you also get the world's best sounding surround processor (plus a tuner) thrown in for free could just be icing on the cake.
In fact, we found that the AVR300's power amplifier section comes surprisingly close to the sonics of the finest separate power amplifiers, so much so that you can fully enjoy the AVR300 as a complete receiver in many high end systems (and, for moderately priced systems, the AVR300 is of course the obvious choice as the best sounding receiver by far, at any price). We tried living with the AVR300 used as a complete receiver, using its power amplifier to drive the loudspeakers of our reference lab system, and we were eminently happy with it, even in our ultra perfectionist system. Note also that, if you have a high end perfectionist system and want to invest in separate power amplifiers, possibly with even greater power output, the AVR300 can work easily within such a system, since it features line level outputs for all 8 channels (including subwoofer output and two distinct back surround outputs).
The only sonic nit we could pick with the sound of the AVR300's power amplifier section is that it imposes some crispness (especially in upper frequencies) upon its inherent solid state sonic personality. When this solid state crispness is added to the solid state sonic personality of the AVR300's processor sections, we wished for a slightly more musically natural sonic personality from the whole unit. Fortunately, we found that a musically natural amelioration of this solid state crispness was easy to achieve by deliberately selecting a power cordset with a little intrinsic self inductance, which bestowed a more musically natural relaxed ease (like a Gaussian filter) to music's upper frequencies. The trick was to find a power cordset (as discussed below) that did not add too much inductance, and did not also impose other sonic problems (from poor quality cordset
(Continued on page 132)