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@erik_squires Would series mode suppressors further complement my Equitech 2Q balanced power transformer? I do use Sound Application and MIT Cables power conditioning cables/units to excellent effect. My experience has been that there’s always a benefit by maximizing elimination of ac noise. (I wish I could get technical details on these products.)
@ptss - I cannot tell you if you will hear a difference, but in my mind there’s very few technologies in audio power conditioning well documented:
Everything else is just some form of shunt noise reduction, which is almost never documented.
The series mode protection is also licened by PS Audio if not others. I consider it the minimum due to:
@mrmb, @soix - Here are some ideas for noise suppression. There are a number of quality noise suppression devices out there. Furman is a good brand, so is PS Audio and Tripplite, but do check out the specs. Here are the specs for a Furman M-8X2, a basic power distribution and noise suppression, and priced at $80.
· Standard Level AC Surge Protection: Merit Class (sacrificial)
· Noise Attenuation: Transverse mode: >23dB, 200 kHz to 10MHz
So let’s explain what this means. Sacrificial means when a lightening pulse hits the device will short the input power forcing a fuse or circuit breaker to blow and opening the circuit.
Essentially, the unit will have to be replaced; the philosophy is it’s better to replace something inexpensive than expensive stuff downstream. This is how I designed the LEMP filter, I had all the noise filtering up front and following by sacrificial electronics. It is good of Furman to specify this, since you know what you are getting. The other philosophy is non-sacrificial, that is a design that has aggressive filtering and stores the energy in a reactive space, thus dissipating the energy more slowly. A good example of this is here: https://zerosurge.com/wp-content/uploads/2018/04/2R-Series-0418.pdf and here: https://zerosurge.com/
There is no reason you can’t combine the two philosophies. J Put the heavy filtering up front, followed by spike suppression.
Spike Protection Mode means the protection is from Line to Neutral and there is no protection from neutral to ground. This is a reasonable concept since neutral is tied to ground at the main panel. There are other arguments against this, stating neutral should be spike protected to ground. However, the more protection one adds, the more the cost goes up. At some point, has you have to evaluate bang for buck. Personally, I put in neutral to ground protection, both as spike and as filtering but then I wasn’t trying to hit a price point.
Joules is the unit to measure energy, equals the work done when a current of one ampere passes through a resistance of one ohm for one second, which is one Watt. Joule units define the energy dissipated by the device; the more the better. 150 Joules here is not much, 3000 Joules is getting somewhere, 6000 Joules or more is healthy. Expect to pay a lot more as these numbers go up.
Peak Impulse Current is the maximum spike current that the surge protection circuit can handle to protect downstream electronics. Again, 12,000 Amps is a starting point, I put in 44,000 Amperes and there are bigger devices out there than what I used. That LEMP filter I designed for the energy system had 300,000 Amps of Peak Current.
The 8/20 microsecond waveform is a standard IEEE test waveform for lightening spikes where the maximum voltage is reached in 8 microseconds and decreases to 50% in 20 microseconds. Therefore, the higher the voltage pulse the narrower the pulse becomes. There are other IEEE standard pulses but this is the most commonly used one.
Let Through Voltage is an important spec. It tells you the amount of voltage that the protection circuit will allow to pass through before the circuit begins to attenuate the spike. Here it is say it will allow a 400V pulse at 125 Amps. Understand there is always a Let Through Voltage, keeping it tame is a tough call and an engineering compromise. Reduce the Let Through Voltage and the pulse circuit works a lot more, heats up, and is in a weakened state when the big spike comes along. Relax the design and the pulse circuit is more able to handle a big pulse but allows more energy through when it does happen. The only good solution here is a good design.
Everything I wrote about so far is about spike suppression, which is lightening and spike noise from motors, air conditioners, etc. This has nothing to do with EMI and RF noise, which is more problematic for sound quality. The spec 200 KHz to 10 MHz is the bandwidth where the EMI filter works and produces at least 23 dB of suppression. In my first posting, I stated look for something that has at least 30 dB of suppression from 100K to 20 MHz, so this unit is a bit on the shy side of what I suggested. Forty dB is much better and it is unlikely you will find anything above 60 dB.
So, is this bad? It costs $80 and for that price, the protection is quite fair. If you have the budget, definitely look for more EMI suppression. If you live in areas where high winds are common, earthquakes, or massive storms, having a lot more spike suppression is a good idea. It is not just lightening that produces massive electrical spikes. A storm knocking out a power pole can do a real number on your system.
- 37 posts total