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SYSTEMS AND MAGIC
This section contains mainly answers to customer’s questions about SYSTEMS AND MAGIC products, particularly about BlackNoise filters use. This FAQ is updated as often as new questions arise.
You can find here any questions relating to day-to-day products use and mantainance, mains line general issues and advice about special situations but concerning common interests. We refer you to the Technics section for the more specialized and investigative aspects, particularly the technical ones.
FAQ - Frequently Asked Questions
1- I would like to connect my whole setup to a single BlackNoise filter.
Are there any contraindications?
Not from a mere electrical point of view. There is no contraindications if, adding the absorption of every single device, the total does not get over the maximum filter rated value.
However, best results are not reached with the whole setup served by a single filter, but instead dividing at least sources from power stages. In more general terms, it is necessary to filter separately the audio/video units that manage the lowest level signals from the electronics that manage the highest level ones. Moreover, using more BlackNoise, you have a synergic effect, a much better one regarding the overall quality than would be expected from simply adding one filter to the other.
2- But anyway, if I would connect the whole setup, could I use an extension strip connected to one of the BlackNoise outputs?
Yes, absolutely, being understood that the maximum BlackNoise absorption must not be exceeded (see also point 5 in this regard). The best results of this setup are obtained using a shielded extension strip and a shielded cable from the strip itself to the filter (see also point 8). In this way, there is no risk of picking up again radio frequency noises and at the same time electromagnetic fields radiated from strip and cable are prevented to spread all around, otherwise the BlackNoise filtering effect could be at least partially nullified. We have either mains distributors DUPLEX, Four, Six, Eight, Slim3, Slim5, Derive! and shielded cables joker, BlackWire plus+, GoldWire, PEARL, that can be used by themselves or exactly to this aim.
The Derive! in particular, thanks also to the built-in shielded cable (a short BlackWire), has been designed exactly to make available more plugs out of a BlackNoise, up to eight if two Derive! are employed on the same filter.
3- But I have no shielded extension strips... may I use some multiple plugs on the two BlackNoise outlets?
Yes, even if multiple plugs are hardly of good quality, are generally not sized for high amperages and are unstable from a mechanical point of view. The power amp, especially if it’s quite powerful, it’s best served directly connected to one of the two filter outlets.
The best overall alternative to multiple plugs is obtainable with our DupleX, engineered expressly to the job!
Incidentally, the sockets on the BlackNoise are oriented in such a way so not to bother each other, either with single or with multiple plugs, allowing a full occupation. We advise against it, but if you really want to do it… you sure can. Wishing to embark upon this way at all costs, use at least some multiples with the Schuko “male” (the part that goes into the BlackNoise socket), because it’s the plug type with the best mechanical grip and absolutely the widest possible electric contact area, at least in domestic environments.
See also point 7 for greater details on Schuko sockets.
4- Why are there only two outlets on the BlackNoise?
The main reason is that the BlackNoise have been designed to be modular, namely (to obtain the best results) to use dedicated filters on different components in the same setup. A design decision rather than a limit. Even with this aim, anyway, providing just one socket would have been an extreme choice. Two sockets on the same filter, instead, are really handy in some layouts: connecting the CDP on a socket and the Phono stage on the other, for example. Surely they are not used at the same time, and if there is the foresight to switch off the unused one, the interaction between the two devices is absolutely zero. Another example would be with monoblock amps, both of them can be connected to the same filter without any ill-side effect: the handiness concept is indeed valid.
See also points 1, 2 and 3 for other considerations.
5- How can I calculate the overall absorption of my system?
First of all, the absorption of every single component needs to be known, this is a useful information to start matching a BlackNoise with any kind of electronics.
There are two methods: through direct measurement or looking for it in the user manual and/or the data plate close by the unit AC inlet. Alternatively, it is always possible to ask the reseller/producer for these information, to search them over the Internet, or to ask a specific question into the many specialized forums on the net.
The first proceeding needs a tester or an amperometric couple(pincer, pair), but we prefer not to explain it. Who already knows it needs no explanation; who does not, better doesn’t try it, because he has to work with 230 V~, a potentially dangerous, deadly situation.
The second method is for anybody. The wording on the instructions (either user manual or plate) may show Watt (W), Ampere (A) or VoltAmpere (VA) values. Otherwise, (more common on power amplifiers), it’s only shown the transformer dimensioning, usually expressed in VA. Another possibility, always related to powerful integrated/power amps, is to find more than a single value shown, like the minimum, the average absorption and the maximum one, at full power. All values have to be considered, but the factors to examine become more complex. To be able to rate the “maximum absorption” value in a proper way, comes into play the speakers sensibility, the specific “audio” output power, the environment dimensions, etc. In these situations, please collect the data available and contact us for any doubt you may have.
Watt information, if shown, can be used directly, with no calculus. If the absorption is instead provided in Ampere (A) or VoltAmpere (VA) units (the latter to be considered as Ampere for this practical use), it’s in any case straightforward to find out the Watt value:
Watt = Mains Voltage x Ampere
Mains voltage is normally equal to 220, 230 or 240 V~ and is showed nearby the Ampere date. The difference between the lowest and the highest value is generally negligible, less than 10%, and for practical use is possible to use 230 V~, as a matter of fact the official nominal voltage in the UE.
Once the Watt absorption of every electronic is known, it’s just a simple matter of adding up all values to obtain the grand total.
6- But I bought some electronics abroad, and they work at 115 V~, not 230 V~. I‘am using them with an external transformer 230/115. Are the computations still the same?
The calculus in itself doesn’t change: an electronic spending 200 W in the USA, spends 200 W in Europe too, because it’s always powered at 115 V~. The information in the user manual or on the back plate is still valid.
But now the Ampere into play are different: 200 W on 115 V~ do not correspond to the same Ampere on 230 V~ :
Ampere = Watt / Mains Voltage
Ampere = 200 W / 115 V = 1.74 A
Ampere = 200 W / 230 V = 0.87 A
In practice, Watt being equal, a mains voltage of 115 V~ doubles the Ampere value in respect to 230 V~.
So, what is the practical outcome? Straightforward: BlackNoise absorption is shown in Watt rather than Ampere, because we are more familiar with it, but this Watt absorption is computed on 230 V~.
The Extreme, for instance, is suitable up to 230 W, 1 Ampere. According to our example, working at 115 V~, the thermal switch would trip in a few seconds, would instead work without a glitch at 230 V~.
So, although the calculation in itself do not change, changes the way to make sense of it!
In the Price List and Comparison Table max absorption values, either for Watt and Ampere, are showed (both for 230 V~ and 115 V~), so to take into account the overseas market and at the same time the direct import gear.
In short, it is necessary to double the Watt absorption of the unit working at 115 V~, so to use its value together with the other units working at 230 V~ in order to be able to choose the most suitable BlackNoise for the whole setup.
One more thing: we are taking for granted that the BlackNoise is connected AFTER the 230/115 V~ transformer. But… what if it’s connected BEFORE? Well, in this case this whole talk is useless. The filter would work at 230 V~ without problems and only a slightly higher absorption will occur due to transformer leakage. But after extensive tests, the best results are obtained AFTER the transformer, so… now you have all the informations you need to choose freely!
Last thing: if the same gear is produced both for the US and European market and its absorption data is obtained through Internet, either search engines or forums, it is better to pay a good attention to the exact voltage it is referred to.
7- Which kind of plug is best for connecting BlackNoise filters to devices and to the mains line? Do the BlackNoise accept the “big” (16A) Italian plugs? And the small (10A) ones? The Schuko plugs? Anything else?
From the Mains line point of view, often we have no choice (unless we change the wall box), while for BlackNoise we may choose between both Italian plugs sizes, the US plug (without the ground pin) and the Schuko one. Full US style sockets (three poles) or even a mix of these and multistandard ones are also available.
But, talking about quality, there is really no choice: the best plug/socket is absolutely the Schuko, followed by the Schuko and finally the Schuko!
Not only it has the widest electric contact area (especially on the ground pins) but also has an excellent mechanical grip: plug and socket lodge together becoming one and the same. The ground connection moreover, due to the peculiar mechanical arrangement, it’s the first one to be made when the plug is inserted and the last to be left, all to greatly enhance security. It is quite hard to tell anything similar about the italian plugs and the US ones either from the mechanical or electrical point of view. An exception is rapresented (in the inlets camp) by the very well build US “Hospital Grade” sockets.
The thought about mechanics could seem fringe… until there is the chance to use an “AudioGrade” mains cable, thick and heavy like a sausage string… in this case there is no issue. But the mechanical strenght is long-term important with “normal” cables too: it means that the cable (firmly remaining connected to the mains socket) does not burden the contacts with its weight, does not strain them in time, does not shake itself loose and is always able to keep the best possible electric contact.
Moreover, once it is plugged in, the Schuko (due to its large circular base) fully covers up a wide socket area not only above but all around the phase and neutral contacts, preventing the entrance of dust, to all benefit of the effectiveness of the electric connection over time.
Other considerations at point 3.
8- And which kind of cable is best for connecting devices to the BlackNoise and the filter itself to the mains line?
A shielded cable, with a good conductor cross-section; excellent section for the most powerful models. The shielding prevents the cable from behaving like an antenna, either receiving or radiating noise and allows the cleanliness operated by the filter to reach untouched the audio gear inlet.
Please, absolutely avoid cables with any kind of passive filtering (inductors and capacitors) within the plugs or elsewhere on their length: the interactions with the BlackNoise are unpredictable and almost never favourable. The only “filtered” cables, at this time, that make an exception are the MIT ones: Shotgun, Magnum, Oracle etc.
In our Price List are present shielded mains cables joker, BlackWire plus+, GoldWire, PEARL, with excellent conductors cross-section, specifically suited for connecting BlackNoises to mains line and to audio gear.
See also points 9 and 10.
9- But It’s indispensable to have shielded mains cables?
Shielding mains cables means avoiding their internal electromagnetic fields radiating outside the cable themselves, inducing noise in the nearby signal, power an even other UNSHIELDED mains cables! It is always undervaluated, but are the audio electronics themselvs that makes noise and inject it on the mains cables: shielding not necessarily is there to protect from “outside” noise!
So the concise answer is: yes, it is almost indispensable! The shielding also prevents the cable from behaving like an antenna, picking up radio frequency electromagnetic fields and guiding them into the electronic: if one is living in the open country could hardly be necessary; living close to a CB, FM, TV or cell phone transmitter shielding becomes instead almost indispensable. The “closeness” can be relative. For instance, it could be possible not to pick up any noises even living in the same building with a transmitter on the roof, but it’s also possible that these noises rise real strongly some hundred meters further away. It all depends by the antenna radiating lobes and by the radio frequency fields reflections. So, strong interference may be present with no “visible” reason, or on the contrary having no interference whatsoever while the next-door neighbour suffers a great deal of.
Another consideration we may rise is even more pragmatic: the in and out cables crowding around the electronics are many, room is never enough and the audio setup shares common spaces with kids, animals, or simple… housework.
In short, unshielded mains cables may happen to get close to signal, power and other mains cables (and if they weren’t in the first place they may move in a second time) and the closer they get to them, the more noise they induce. Anyway, apart any shielding consideration, NEVER EVER tie them together.
So overall, shielded mains cable forms a not negligible sort of “preventive insurance” to a whole, hard to forsee series of events.
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