Balance: Benefit or Bluff? Page 3

All the usual mixing and matching review procedures were useless; it was out of the question to make direct comparisons. I was fought every inch of the way, precisely because these Audio Research components are of true balanced design; ie, fully balanced differential circuitry is present at their every stage, including cross-coupling between hot and cold signal paths. It didn't take me long to realize that you can't mess with true balanced components; fully balanced connections, in and out, is all that will be tolerated if satisfactory hum and hiss performance is to be obtained. With the ARC equipment, this meant that comparison with normal phono equalizers and line controllers was almost impossible. If I didn't know better (and perhaps I don't), I could be persuaded that the closed and self-perpetuating circle generated by balanced systems is a deliberately constructed barrier raised against the true comparative assessment of their subjective quality.

For example, take an Audio Research V-series power amp with its balanced input (again, I'm not singling out ARC). In my experience, it won't perform at its best unless it's driven balanced. If you want to hear this amplifier in an unbalanced system, then I strongly advise you to acquire the relevant unbalanced/balanced converter, the Audio Research BL1. Regardless of the latter's exceptional quality, you've added a second set of connectors, cabling, expense, and grounding.

Yes, it's true that using the amplifier with a high-quality balanced control unit, such as the LS5, facilitates evaluation of the amplifier—that is, assuming that you're totally familiar with the balanced preamp's quality. If not, you have to check it out by turning to your favorite digital source, which, again, will most likely have "normal" outputs. You therefore have to bring another unbalanced/balanced converter into action, again resulting in an unwanted step in the chain.

Cautious words
Enough examples. With no disparagement intended against the fine Audio Research products mentioned above, my experience with balanced components has been that they're not necessarily better than normal components. Indeed, they can often sound better via their subsidiary "normal" signal connections. Enough equipment has passed through my test setup that I feel comfortable making a few cautious generalizations.

True, the balanced condition does result in lower noise levels and improved immunity to EMI and RFI, local ham radio, CB operators, or switching pulses from heating or refrigeration thermostats. On the debit side, stereo images often lose absolute focus, stage width, and depth. Sounding less "locked in" to the music, the balanced components often exhibit losses in dynamic resolution, dynamic contrast, and rhythm. Typically smooth-sounding and laid-back, a balanced component can be less involving, lending the music a "downbeat" impression.

This shouldn't be seen as a write-off of all balanced components. However, even though the differences I mention are not huge, such differences are what the High End is, or should be, about.

Interestingly, the characterizations I mention are also those associated with less-than-first-rate connectors. Taking this together with the necessary additional circuit complexity required by "balance," these factors make some sort of sense. Something as simple and direct as a Conrad-Johnson Premier Eleven power amplifier—a "normal" input design—couldn't be built in balanced form without compromising its engineering purity and its sonic purity.

Grounding 'n' timing
There's an element of circuit philosophy that's relevant here: The most dynamic-sounding, best-timed audio systems have fundamentally good system grounding. I don't mean just the chassis ground paths. The signal ground is defined as a true reference point, carefully organized, even to the extent of a hierarchy of grounds focused at a single star point. These are scaled and organized according to their role and the signal source they serve. Such organization, if successfully effected, endows the system with a subjective sense of poise and equilibrium, the sound set firmly on the ground rather than precariously "balanced" above it.

Once a fast, well-tuned audio system has been set up, it's fascinating to observe how quickly and catastrophically its sound can be made to subjectively fall apart, stage by stage, as the main structure of the electrical organization and grounding is disturbed or dismembered. In one highly tuned example, a sophisticated audio system, featuring active crossovers, had been set up in every detail but AC mains supply. I was worried about its conspicuous failure to perform properly—the "improved" system actually sounded less musical and entertaining than the simpler passive implementation of the same components, used with lower-grade power amplifiers.

Article Contents
Share | |
Site Map / Direct Links