Thread: Boulder 865 Integrated Amplifier

The 865 amplifier might be one of the most expensive ever to grace the pages of Hi Fi Choice, but it's also the most affordable in the entire Boulder range. To put this into perspective; Boulder's 'entry-level' 810 and 860 pre/power pairing retails for Rs 8,82000, while at the other end of the scale, the 2008 phono stage costs Rs 17,03,000 and the 2050 monoblock power amps are Rs 1,51,70,000 a pair! The 865 is, therefore, a keenly priced component in the general scheme of things.

While the 865 is still expensive, the fact that its design and construction comes from the same stable as the distinctly ultra-fi kit should be a definite advantage. The 810 preamplifier and 860 power amp mentioned earlier are the ingredients that go into making up the 865, which is why the integrated looks like a higher version of an 810. According to the company literature, the 865 can deliver 150 watts into both four and eight ohm loads. This is quite unusual for a solid-state design. As a rule, valve amps have the same power regardless of load and, up to a point, transistor designs increase output as impedance decreases see our interview with Jeff Nelson in this feature for more on this subject.

As is nearly always the case with high-end American products, this is a fully balanced component. Where Boulder take this a step further is in the use of exclusively balanced XLR input and output sockets. If you have a source component that only has single-ended phono sockets you will need a cable that has XLRs at one end and phonos at the other, or a converter plug such as the Boulder ones that UK distributor Metropolis loaned us for this review. There are four inputs and one auxiliary output that can be used in a fixed or variable form. In other words, it can be an output to a recorder or processor, or to a second power amplifier for bi-amp operation.



Each input can be named, but the sheer range of characters including upper and lower case letters, numbers and an assortment of 'runes' and symbols, complicate the process somewhat. A list of these in the manual would have been useful. Input gain can also be adjusted so that different sources can be matched as much as possible. Difference in recording levels tend to be the dominant factor, but older components can have much lower output levels than modern ones. Integration with what Boulder calls 'home-theatre' [sic] is aided by a bypass mode that you can assign to an input from a multichannel processor. This uses the power amplifier side of the 865 to drive front left and right channels.

Boulder is unusual among the high-end companies for making extensive use of surface mount components. These are chosen because Boulder considers them to sound better as a result of reduced capacitance and inductance: the fact that they don't have 'legs' in the same way that regular capacitors and resistors do, being a factor here. A discrete-resistor stepped volume control, developed for the 2010 preamplifier (Rs 23,22,000*), allows half-decibel increments in level via the large rotary on the amp, or the attractively curvy remote handset (which probably accounts for Rs 19, 350* of the retail price alone). The volume range goes from o to 100dB in half-decibel steps, but in practice, you are unlikely to need more than twenty per cent of this, although this may vary according to speaker sensitivity.The switches on both amplifier and remote are interfaced with ball bearings, which is a neat, albeit expensive way of doing things.