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Like the one PS Audio sells? It's just an isolation transformer, right?
Follow Ups:
Isn't it a bad idea to put any big inductor for cleaning up
the power supplies of Class B amps? These amps must pull
huge surges of power from their supply rails to handle
signal transients, and anything which "slows down" the
supply side will make the amp sluggish-sounding and flatten
the dynamics, I'd expect. Am I right here?I'd think inductor-based transient suppression would be a
good idea for most all other audio equipment, except Class B
or Class AB power amps. My ideas are not very clear, so
please comment! :)Tarun
Choke-input power supplies provide several advantages over capacitive only types. First of all, with a choke, current is drawn from the ac line over a wider time span or conduction angle, unlike capacitor only supplies that pull large peaks of current at the crest of the ac sine waveform. This results in a larger power factor as opposed to capacitor only circuits. More average power can be obtained with choke plus capacitor supplies vs. cap only. When an amp needs to deliver a large surge of peak power/current, this current is pulled from the filter capacitor(s), not the inductor. The total capacitance value of the filter capacitor bank times voltage squared times one half constitutes the stored energy in joules. If you wish to have large reserves of energy to handle peak current demands, you'll need lots of capacitance, and low ESR. Unfortunately, this results in poor power factor regarding the ac line. A capacitor input filter has a typical power factor of 50 to 60 percent. This limits the power available from a 120 volt / 15 amp outlet to 900 to 1080 watts (actually, volt-amps). A "softer" capacitor bank (less capacitance, and/or more ESR) will increase power factor, but at the expense of reduced peak current capability during demanding transients. With chokes, this tradeoff does not have to be made. I've seen choke input filters achieve 75 percent or more p.f. (1350 volt-amps). With a choke input, you can use large capacitance for peak current delivery and not suffer a reduced power factor. Also, during a sustained transient, while the capacitor is being discharged, the inductor is either being energized or de-energized, depending where the ac line voltage is. In either case, the inductor current is flowing into the cap and the load. This results in the output being held up longer than it would be without a choke. The choke increases both the peak current delivery, and average power capability.
Also, the choke with the cap forms an L-C filter, which is much more effective at filtering noise, than a cap only.
The price paid for these improvements are substantial. A good choke, with high current capability, and low dc resistance is quite costly. Also, it is quite heavy, and requires lots of space. Mother Nature will gladly trade with us, but she doesn't give anything away. Best regards.Claude
If this unit connects to a 208/220 line and converts it to a balanced 110 situation- positive 55/ground/negative 55- it can give massive relief from A/C line noise. If it's a device that just plugs into a 110 A/C source it won't work any better than a $10 corcom filter.
Bill, you ever take apart one of those Corcom thingies??? Looked at those easily saturable ferrite cores? While the UO isn't, and can't provide those benefits of a properly specified balancing or isolation transformer, and its marketing hyperbole is specious at best, it is a far better engineered CMC for Audio purposes than a Corcom, as I described in another post in this thread.
Have you listened to a variety of Corcoms with your components. Have you listened to the impact of a UO? Or are you relying on non empiricly derived engineering expetise?
I never said those corcom thingies were all that great- but after having tried both those and a number of other filters that have come along from time to time for some thirty years what I can say with certainty is that if you want to significantly exceed their performance you have to have a transformer derived balanced power supply. As for what I use, along with most everything else I build my own filters.
This being the tweakers asylum, diy and value should certainly be on the table. At $299+ the UO with its $9 powdered iron torroid core (but it is better than a $.50 ferrite core) does make one wonder about the expression 'more money than common sense'. My comments were to point out that UO doesn't use the typical ferrite cores, and IMO, the implementation is pretty slick, regardless of the marketing claptrap.
But your point about doing it right is spot on. The proper route for the diy hobbyist is to both phases (if available) and step down and balance.
The Ultimate Outlet is not a transformer. It a balum with the hot and neutral wires wound equally on each half. The wires are in direct electrical contact from the male IEC to the duplex recepticle.
Certainly not the UltimateOutlet.... tis certainly not used as a balun, but rather as a CMC, common mode choke. The description as a balun is simply marketing hyperbole, at best. What differentiates the UO from other line filters that use a cmc, Corcom, Qualtek, etc... is that the UO uses a oversized, powdered iron torroid, #26 mixture, as opposed to the typical, easily saturated ferrite composition. What this allows is that it not only functions as a cmc (with caps as in most line filters) for dealing with common mode noise, but that not easily saturable formulation allows the windings to function as low inductance, independent chokes in dealing with differential noise.
Its a sad commentary that a well designed, clever device is marketed with specious nonsense, the nonsensical description of a balun (balanced to unbalanced) oft repeated by gullible reviewers, lowered impedence??? total bushwa!!!.... sad indeed.
It's appreciated.
With 2 sets of windings. That'd probably work very nicely at cleaning up grunge from the power. No telling exactly what kind of magnetic material they're using, but you can experiment using ferrite toroids salvaged from a discarded torroidal transformer, computer power supply or some older compact fluorescent lamps. I doubt that it's an isolation transformer unless we're talking about maybe a couple of hundred watts max. No way an xformer that size would handle 15A.
Kind of looks like an attempt at configuring a toroidal transformer as a choke. If it's just a one to one transformer it's not going to do anything except separate suckers from their coins.
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