What exactly do you mean by "fully" shielded?
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OK, well you raised a couple of things. Lets talk about the CDP. Any digital device (CDT, CDP, DAC, DVD player, computer, etc) should use a shielded cable because the power cable can act as an antenna that will broadcast digital RFI ("hash") into the air. (Some computers and monitors even have a ferrite bead at the device end of the cord to capture digital RFI). In addition, the cord can also introduce hash into the power line itself, so you want to put these devices either on separate circuits from the other stuff, or, if you're using a power conditioner, most modern ones have a couple of "digital outlets" that are for these devices. They have filters on them that keep the hash out of the rest of the power lines. So always use shielded cords on digital stuff. Now about the cords themselves. The reason a lot of manufacturers use the ferrite beads (even though they're not as effective as shielding IMO) instead of shielded cords has to do with UL approval. UL approval for a shielded OEM power cord (and therefore the device itself) requires that the shield be attached to ground at both ends of the cord. Such a cord will shield OK, but by connecting the shield at both ends, a ground loop is formed and so such cords are susceptible to hum pickup. Most aftermarket shielded cords, have the shield connected to ground only at the AC plug end. This is called a "floating shield" and is the best way to do it. DO NOT use a ground-lifting "cheater plug" with these cords or you lose the shielding properties. I'm not going to recommend a specific cord, but make sure you ask the manufacturer three questions (and do get answers or don't buy the cord): 1.) Is it shielded (and you might ask braid? or foil? or both?) 2.) Is it a floating shield? 3.) Which end is the shield connected (you want the AC plug end) Two other things: One has to do with wire size. For some reason (I don't know why since they don't draw a lot of current like amps) CDPs and DACs seem to perform best with big conductors (10 AWG, or slightly smaller 12 AWG) Sometimes it's hard to find these sizes (especially 10 AWG) shielded, but they are available. The other has to do with the use of balanced power units. If you are using a balanced power unit to supply power to your front end stuff, you don't really need shielded power cords because noise in the power line is self cancelling, and as long as the conductors are twisted, the cord shouldn't pick up RFI/EMI. Even so, dgital devices should still use shielded power cords, even with balanced power, because the balanced power doesn't keep them from broadcasting RFI. |
Pure Note Paragon is fully shielded. I have three of them in my system. Very flexible and quiet. http://www.purenote.com |
Nsgarch, I think I'll have to disagree with you on the use of shielded cords for digital. Just that my experience has been different. I use Audience cord on my dac and tried shielded cords and always preffered the sound of the dac with Audience cord. Clio, borrow cords from cable company and see if a shielded cord will beat the Audience. Using shielded cords in my system always resulted in darker, more closed-in sound. The noise rejection usually comes at the expense of dynamic range. I am now trying out the Audience cord on my amp as we speak, in addition to the one I already use with the dac and I like what I hear this cord does on the amp. But of course, the only way for Clio to find out is to try different PCs. |
Audphile1, your post is unclear. Unshielded Audience versus shielded what?? You may be comparing apples and oranges in terms of the other properties of the cord(s) such as gauge, conductor material, length, etc. Shielding, if it is a floating shield, and all other characteristics the same as the unshielded cord, should have no sonic effect. A floating shield does not carry any current, so cannot effect the energy transfer of a given cord. I'm not debating what you experienced. I'm just not sure you were making an equivalent comparison. I'm wondering therefore, if the Audience cord is simply a larger gauge cord than your shielded one. |
You can buy a Volex shielded 14 AWG cord from Allied or Carlton-Bates for less than $20. Chris VenHaus (VH Audio) offers his shielded "Flavor 1" for $115 and up (depending on which termination options you choose) with a 60-day return priviledge. Silver Audio WattMaster is also an option at $525 with a 30-day return option. I certainly haven't compared these on a Trumpet so I have no idea whether more money would translate into better sound. You'll have to experiment. |
Nsgarch, I compared Audience to Shunyata Diamondback, PS Audio Prelude and Acoustic Zen Tsunami+. Found Audience to sound best with the dac and other cords to be good on pre and amp. However, Audience also was also very good on the amp as well. Prelude is out of the picture altogether as I liked it the least. It was the most shielded(I think) and sounded worst than the stock cords. I don't know what gauge Audience is but I don't think this is what contributed to the differences between the cables in this given example. Anyway, the best way to find out what works is to try. But Audience is one cord I wouldn't hesitate recommending. |
Greenman - I think the Wattmaster may be overkill on the Hagerman and at 8 gauge is more suitable for an amp. However, the Powerburst 2 looks pretty viable and will save me some cash. Nsgarch - I would like some recommendations if you could as I'm interested in the floating shiled design. If you prefer to email me privately please feel free, you've been a big help in the past with some issues I had with a previous phonostage that had bad grounding issues so I value your advice. Overall, the Volex (which I may buy anyway as I have been hearing a lot about this cord and is a no brainer at the price), Pure Note, Silver Audio, and VH Audio Flavor 1 all appear to be shielded at both ends. Keep the advice and suggestions coming, this has been very helpful. |
Audphile1, I do not know that your comparison of the Diamondback and Prelude against the Audience is a good example of shielded vs. non-shielded: The Audience is a good PC, while the Diamondback and Prelude are primarily entry-level. I have tried the Audience in my system, and although I preferred the Shunyata Taipan Helix Alpha (non-shielded) and Cardas Golden Reference (shielded) on my amp, and the Cardas on my CD player, I thought the Audience sonically a better cord than the Diamondbacks I was using for a while. |
Audphile1, it wouldn't cost anything but a little of your time (and forgive me for that if you're a $400/hr. attorney!) for you to call or email the makers of all the cables you compared to get the actual specs, particularly shielding topology (connected at one end or both ends?) and especially conductor size. This would be very helpful to you in correlating what you're hearing to the construction of the cables you're using. My personal experience with amps and DACS has been the bigger the conductors, the better the performance FWIW. Clio09, I agree, the 8 GA. is definitely overkill for a phono preamp, whether tube or SS. 14 GA. should be more than enough. Your comment "all appear to be shielded at both ends." is a bit confusing to me. Here's how it brakes down with respect to shield topology (layout): 1.) One shield (or two, like a braid over a foil, but acting as one) connected to the ground pin of the AC plugs at both ends. This is true for OEM supplied shielded cords because of UL regulations. However, by being connected at both ends, the shield can carry current. This arrangement creates two problems: a.) ground loops (hum) and b.) the shield becomes an additional (unwanted) ground conductor leading to electrical problems (capacitance/inductance) that can affect sonics. 2.) One shield (or two together as above) connected at only one end (floating). Most manufacturers connect the shield at the AC plug end, but some connect it at the component end (I don't know why and wouldn't buy one of those myself.) In this arrangement, the shield can't carry any current (no point-to-point connection) so it simply acts like an antenna attracting RFI and getting it (draining) to ground before it can add itself to the hot conductor. Or, with digital equipment, preventing the hot conductors (bottling them up so to speak) from broadcasting digital RFI produced by the component's power supply, into the air. 2a.) One variation is the "double floating" shield (Cardas uses this I think, and maybe some others like Virtual Dynamics?) Here, there are two (usually concentric) shields (like the foil and braid mentioned above) BUT they are insulated from each other and do not act as one. Instead, one is connected to only the AC plug, and the other is connected to only the component plug. So they're both floating, but from opposite ends of the cord. I've never (to my knowledge) used one of these -- sounds good in theory. Might be overkill for audio applications, I don't know. 3.) Shielding that isn't connected at either end. You can think of this as a ferrite bead or donut that has been stretched out or extruded to be as long as the cord itself! And just does its work by the sheer absorbing power of its material. A well-known example of this would be the Purist Audio Design "Ferox" shielding, a thick layer of powder or paste that surrounds the conductors. Another manufacturer uses a jacket of metallic beads to do the same thing. |
Nsgarch, thank you. But I got better things going than calling or e-mailing power cord manufacturers. It would be great however if you can educate me and possibly few other people here about power cord design and what advantages and disadvantages each of the designs have. It certainly looks like you have conducted your research already. So why not share? |
Nsgarch - Thanks for the clarification. Pure Note and Volex fall into #1 as they are UL compliant according to their literature. VH Audio uses foil and braid as in #2 from what I could gather. I am not sure about Silver Audio as they use soem type of mu metal jacket and 4 shielding networks in their cable. I did call Purist Audio and understand they use Ferox in a similar approach to Star Technology. I actually have an opportunity to get a Purist Audio Musaeus for a pretty good price. Would this work? |
Audphile1, I always establish my short list (cables to audition) based on design and construction. Then I listen. I'd be happy to provide you with info about your choices, but have never had occasion to research those particular cables, so I don't have it. Clio09, as you know, I'm a card-carrying Purist fan. Purist has never let me down. A perfect example occurred today: All my (significant) cabling is either Purist Venustas or Dominus. But I still have some oldie/goodies (MIT, Straightwire) in less critical places like FM tuner, cassette deck etc. Musaeus is the entry level Ferox shielded cable, and I decided to replace the oldie/goodies with it as the opportunity arose. Today I received a 1m Musaeus RCA bought from a member. I swapped out the old MIT 330 from my modded Technics tuner which I only listened to casually for NPR and background classical. I'd decided the recent mods and alignment didn't accomplish that much. Well boy was I wrong! Real "audiophile" sound came out, I was quite amazed, mainly because I wasn't expecting anything spectacular. You know, there was a time (ca. 1990) when MIT 330 was the best IC you could buy! Anyway, you're interested in a PC. According to the Purist specs, the Musaeus PC is 14 AWG which should be perfect for your Hagerman. It is foil shielded though, not Ferox like the Musaeus ICs. |
Just wanted to provide an update. The Purist Audio Museaus arrived. I purchased it from the Cable Company and thought it was used, but it is actually new in original packaging. Solid cable and very well constructed. It is also flexible so it can be maneuvered easily. I plugged it in to the phonostage yesterday and it sounds great right from the start. I imagine it will only get better as it continues to burn-in. I may have to try their ICs next. |
Audphile - The Audience is a tad warmer than the Purist Audio Museaus, at least that is what I am hearing now. After the pc has had a chance to break in we'll see if that remains the same. My guess is it will, and it will exhibit some more of the transparent qualities and detail that I am hearing now. I still will be using the Audinece, next on a new CDP I'm getting. This pc is very versatile and has been used on my preamp, DAC, and transport at various times, with very good results. |
I am getting the TRL modified Sony DVP-NS900V with the additional battery power modification. This is an interesting mod in that the battery power supply only affects the analog stage. The digital stage will still require a pc and that is where I'll use the Audience. I expect the Audience will work nicely on it, as it has on my other components. I do need one more pc to place between a variac and a PS Audio HC/UO. Right now I have the Audience in that spot to keep it in use while I await the CDP. |