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Blue Circle has been researching powerline conditioning and filtering for a very long time… more than twenty years. The BC60X1
represents the culmination of these many years of discovery and experimentation. There are actually several different, though
related, products contained in the 60X1 chassis.

If you look at the back of the stock version (shown below) you will find twelve outlets. Extra outlets (or fewer) are available upon
request. The six outlets on the left offer noncurrent-limiting filtered power, and the amount of filtering is truly massive. There is
2.5 times more filtering in the 60X1 than in the studio reference BC6020 line conditioner. It is important to note that these outlets
are truly noncurrent limiting. The breaker in your main panel will trip before this side of the 60X1 will even begin to think about
offering the slightest opposition to current demand. You can hook up the biggest, meanest, current-hungry amplifiers to these
outlets and not have the slightest worry about affecting their dynamics, either macro or micro.
The BC60X1 also contains a special low-frequency filter we call the X1e. Most line conditioners, including our own, tend to focus on r
adio-frequency (RF) noise above 50 kHz. But our research has shown that due to the increased use of devices such as switch-mode
power supplies (almost every computer uses one) and compact fluorescent lights (CFLs), there is more and more noise being
generated at lower frequencies, mainly from about 5 kHz to 50 kHz. The X1e module was developed to target this specific range of
The six outlets on the right offer both filtered and balanced power. Balanced power is ±60 V instead of 120 V to ground. To produce
balanced power, a transformer with a grounded center-tapped secondary (output) is required. Transformers, by their very nature, have
a tendency to oppose very fast (transient) current demands. For this reason we recommend that only line-level components like DACs,
phonostages, and linestage preamps, or low-power amplifiers should be connected to the balanced-power outlets. Power to these
outlets is limited to a combined total of 800 W.
The balanced power outlets offer another advantage. First of all, not only do they share all the filtering of the other outlets, there is also
some additional filtering on the secondary of the transformer. Another advantage to using balanced power is a phenomenon called
common-mode rejection or CMR. This can best be explained visually so refer to the figure below.
Illustration of common-mode rejection
When the center-tap on the secondary is tied to ground as in the figure above, any noise on one side of the grounded center tap is
180˚ out of phase with the noise on the other side. This means that the noise on either side of the center tap will cancel out. This
adds another level of filtering to these outlets. It also prevents any noise being generated by one component (such as clock noise
from a DAC) from leaking into the power supply of another component connected to the conditioner. This offers a great advantage to
components that are processing very low-level signals, like phonostages. But, we feel that it is important that you experiment with
your system. You may find that some components work best on filtered power only and others on balanced and filtered power.
You must be the final judge as to what works best for you.
If you look in the middle of the back panel you will see a switch labeled as “quiet” and “bypass”. This switch controls a DC-offset
blocking circuit, similar to the RPD-15. This is another feature of the BC60X1. DC offset in a supply voltage will cause a mechanical
“growl” in a transformer. In the “Quiet” position this circuit is engaged and any DC offset is blocked. If you have no DC offset then put
the switch in the “Bypass” position, and power is connected directly to the transformer.

On the bottom of the chassis you will find a reset button. This is connected to an internal ground fault circuit interrupter (GFCI).
Whenever you are working with balanced power where both terminals are hot (neither are tied to ground), a GFCI is a necessary
safety feature. If the GFCI should trip due to a grounding fault, power will be cut to all outlets. Pressing the reset button restores power.

The final feature of the BC60X1 is an internal user-replaceable surge protector, similar to our TSPD. We are aware that surge
protectors have a bad reputation. Many people say that they tend to degrade the sound of a system over time. This is certainly true
of many MOV-based surge protection circuits, but at Blue Circle we have found a simple and effective way to construct surge
protection circuits that do not degrade the sound, even after years of use. If you are interested in the technical concepts, please feel
free to contact us. We would be happy to explain.

So, to sum up, the BC60X1 offers six massively filtered noncurrent limiting outlets, six filtered and balanced outlets with common-mode
rejection, a DC offset blocking circuit, and user-replaceable surge protection. This is the finest powerline conditioner offered by Blue
Circle and we feel it is among the finest made anywhere, by anyone, at any price.
Dimensions: 17” wide x 14.5” deep x 4.5” high.
Weight       : 42 LBS.
Features     :  6 filtered, 6 filtered/balanced hospital grade outlets.
The BC30X1 has many of the features that the 60X1 offers at a lower cost. It has six noncurrent limiting filtered outlets that have about
two-thirds of the filtering of the 60X1 or about 1.2 times the filtering of the BC6020 studio reference line conditioner. It has the same
X1e low-frequency filter module. It has two balanced power outlets which offer common-mode rejection. They are limited to 120 W
total power. The 30X1 also has the same internal GFCI, and the same user replaceable surge protector. Though it is not a 60X1,
it is still a versatile, highly effective, and more affordable, line conditioner.
Features    :     6 filtered, 2 filtered/balanced industrial grade outlets
Dimensions:   17" wide x 3.25" high x 10" deep  
Weight       :   16 LBS.
Contact:  bcircle@bluecircle.com  /  519-469-3215