Mating power cords with APL 3910

Tvad: All i can say to that is that you must have one helluva fast internet connection to have fully read that post and responded so fast!!! That was like lightning!!! Sean
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From what i've seen and read about the Hydra's, they are simply very sturdily built power strips using high grade parts with built in parallel line filters ( like Audioprism Quiet Lines / Enacomm AC filters ) and heavy duty MOV's for surge suppression. Nothing more, nothing less. While i would not really call them "current limiting" by design, the outlets appear to be wired in "daisy chain" fashion rather than to one common point in parallel. Under very heavy demand, this wiring arrangement may cause voltage sag or fluctuations as one gets further away from where the AC feeds into the first outlet. In my opinion, all of the outlets should be wired back to the AC input jack independently of the other outlets for best results, but what do i know??? : ) Sean
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FrankG: The Hydra 4 & 6 use "silver buss straps" while the Hydra 8 uses "copper buss bars". Evidently, the buss bars are heavier gauge than straps, so they went to using the cheaper conductor ( copper instead of silver ) due to the greater amount of material needed.

Having said that, the outlets are all still wired in a daisy chain fashion. AS such, they rely on the power distribution of one set of wires to the first outlet to feed ALL of the remaining outlets in the Hydra.

This was a poor circuit design in my opinion as the last outlet has the longest path and will only recieve the amount of voltage and current that isn't soaked up by the other outlets prior to it. This means increased ripple and voltage fluctuations for all the devices tied to a Hydra.

Had they wired everything to one central junction point, all the path lengths would remain consistent and independent of each other. The only potential for sag or ripple would be left up to how much current that central junction point could pass and what the power cord from the wall outlet could provide.

Since the outlets are all wired in a parallel-series daisy chain fashion in the Hydra, it increases the potential for circuit crosstalk and inter-circuit contamination. That's because there's nothing stopping internally generated noise from within a component from feeding back into the other outlets that it is directly tied to via the buss bars. After all, it's not like there is any type of isolation or filtering device between each outlet and the buss bars themselves.

If they were smart and went with the central junction point approach, they should have also included another parallel line filter at that point. This would have filtered everything prior to distribution into each outlet. With the incoming AC cleaned up, the parallel line filters at each outlet have less work to do. They would only have to soak up the internally generated noise within the component itself and the remainder of RFI that got past the first filter at the main junction.

Even if internally generated noise were to sneak past the individual parallel line filter at each outlet and make it back into the distribution node, it would run into the master parallel line filter before it could pass into any of the other outlets. This approach would catch RFI / internally generated noise coming and going from the distribution node and at each outlet. There is NO chance for cross contamination using this approach, unlike the current design.

Like i said, it is a fancy power strip using higher grade parts, parallel line filtration and high energy MOV's. As usual, it is a lot of money for an under-designed "audiophile grade" product that relies on cosmetics and marketing hype. I'm NOT saying that such a design can't or doesn't provide benefits as compared to other similarly designed products, only that there is more potential to be had from a product that offers a more thorough design and build. Sean
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PS... If i, an off the street knucklehead that has the reputation of being a "know-it-all internet shit talker", can figure this stuff out, what's going on with all of these high priced engineers with those fancy degrees??? How come they can't figure this kind of stuff out???

PPS... I wonder how many toes i stepped on by telling the truth about this one??? I can already see the raging private emails, negative public responses and hear the voices grumbling amongst themselves.

PPSS... I wonder how many ideas / design concepts for various products that i've given away for free over the years via public discussions on the net??? I'm beginning to think that i could have been a very rich man. That is, if i was both more motivated and greedy : )

Balanced power can work with some gear, on others, it makes a mess. I'm not a fan of toroidal based PLC's and somewhere in the archives, there's a thread where i explained why going into technical detail with a full explanation.

To sum things up, toroids suck compared to a good "iron core" type old school transformer. The figures that BPT provides for the 3.5 as seen in the review at Six Moons confirm the figures that i posted in that thread. Sixty to seventy dB's of noise suppression with a toroid as compared to one hundred twenty to one hundred fourty five dB's of noise suppression with an ultra-isolation iron core transformer isn't hard to figure out which is best. Granted, ANY noise suppression is a good thing, but if you're going to spend that kind of money, why not get something that REALLY works???

Either way, you should contact the manufacturer of ALL of your components and find out if they are compatible with a balanced AC input. Assuming that all of it will may be a mistake. Then again, the gear that won't work with balanced AC is gear that already has polarized noise suppression built into it and there ain't much gear like that made nowadays. That's because it requires design skills and money to produce. Sean
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Once again, threads are overlapping. Rather than double post, here's a link to the other thread where Grant ( Tvad ) and i discussed alternatives to the Hydra. After reading all of this and seeing the opportunity to fill a void in the market that has now been highlighted for all to see, i'm sure that a manufacturer will start producing such a unit sometime shortly. Sean
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PS... Rgs92, thanks for pointing that out. I never saw your comments about the Hydra as most of these type of products don't interest me for the aforementioned reasons. Having said that and as i've mentioned before, one doesn't necessarily need to listen to a product to have a good idea as to what to expect out of it. That is, if they know how to dissect it electrically and can understand what those electrical characteristics may translate to sonically. Someone should point this thread and the others where i've posted similar comments based on logical deductions to Jtinn and and his group of cronies. They don't seem to think that such things are possible.

Thanks for the response Grant. Having said what you did though, you never provided any type of rebuttal pertaining to the facts that the outlets are all wired in daisy-chain fashion with the resultant potential for heavy current draw to modulate the AC voltage & current available to other devices or that there isn't the potential for crosstalk / cross-contamination from outlet to outlet.

Parallel filters are just that i.e. parallel to the existing path. That doesn't mean that these filters absolutely will absorb all of the incoming or outgoing noise, just that there is a parallel path to the filter for the noise to take outside of heading into the next component or back into the main AC feed.

Having said that, I would be curious as to what level of "isolation" is provided from one outlet to the other outlet within the duplex and how much isolation there is from one duplex to the next. Obviously, this would be somewhat frequency dependent, but if Shunyata has conducted the exhaustive type of R&D that you claim that they have in designing this series of products, all of this data should be readily available. For that matter, the amount of voltage / current that can be pulled from one outlet without creating sag in any other outlet within a Hydra should also be a matter of recorded data that i and many others would be interested in. I say that because others have questioned the use of a Hydra for both their amplifier(s) and line level components simultaneously.

As far as having an agenda, i'm not involved in the audio industry in any way, shape or form. I'm simply sharing my own technical observations and analysis based on the descriptive information as provided by your website and other sources that supposedly received their information directly from Shunyata. Feel free to confirm or deny any of it at your leisure, but please be at least somewhat specific in your response. Saying that something doesn't happen or isn't possible when logic dictates that such things do occur and / or are possible isn't much of a reply from a company that makes high profile, high cost products of a technical nature. Sean
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Samuel aka Grant: Thanks for taking the time to respond and provide more info. I was beginning to wonder if this was going to be like the last thread where i asked questions of a manufacturer and they never responded. They did respond to others within that thread both before and after those questions / comments, but they somehow seemed to overlook what i threw their way. Wonder how that happened ??? : )

As to my previous comments, i based them on the info and pictures available on your website. As such, you might want to update your website and check the wording used. While you state that the Hydra 8 is parallel wired rather than daisy-chained, where would the use of copper buss bars come into play then? The info on your website makes a big deal of how heavy the buss bars are that are used in the Hydra 8 and even shows them, but doesn't actually show the internal construction of the unit. As such, one is lead to believe that these units are all based on the same basic design / operating parameters with the only variables being the amount of outlets available. Evidently, such is not the case. This is confusing to say the least.

"The measured Voltage drop across a 2" 9 gauge silver plated buss strap is so small that it is irrelevant to operation and could not possibly create a voltage sag that would harm or otherwise alter the performance of electronics that are connected. There will always be a common point at which current converges no matter the wiring or buss arrangement"

I never said that voltage sag would result because the Hydra's used buss bars. What i did say is that there was more potential for sag or "modulation of the voltage" for the outlets later in the line because of this type of lay-out / wiring scheme.

If a device is plugged into the first outlet that pulls gobs of current on a dynamic basis, all of the outlets wired behind that first outlet will demonstrate at least a small amount of ripple. There is the potential for greater sag as the current draw increases. That's because the current will go where it is being drawn first and then whatever is left will "meander" downstream accordingly. If there is enough pull "upstream" at the first outlet, there's not as much current left to wander "downstream" to the other outlets. That lack of current is what causes voltage sag.

If you had multiple rivers ( individual outlets ) with their own feedpoints ( parallel branch wiring ) to the ocean ( wall outlet ), the potential for any starvation downstream is reduced. That is, so long as the ocean ( wall outlet and power cord ) could provide enough flow. That's because each parallel branch doesn't see what the other branches ( outlets ) are pulling whereas with the daisy chain arrangement, one river ( outlet ) feeds into the next in a series arrangement. If the first river ( outlet ) restricts the flow, all of the other rivers ( outlets ) feel the consequences.

Based on the info that you provided in this thread, this type of situation could only apply to the units that are wired in "daisy chain" fashion i.e. the 4's & 6's. As mentioned elsewhere in this post, the use of buss bars within the 8's still leaves me a bit confused though.

As to the link that you provided ( THANK YOU for making it simple for all of us to follow along ), i never, not once said that the Hydra's couldn't provide noise reduction. Anyone that has ever experimented with parallel noise suppression circuity would know better than to make such a claim. What i did question was the amount of isolaton as referenced over a specified bandwidth that the Hydra's provided from outlet to outlet. The test results that you linked to here didn't cover anything like that.

For sake of reference, my main concern is what happens when a component plugged into the Hydra generates AC noise / interference / RFI and tries to pump that back into the AC system??? Not only would such a test tell us how well each component is isolated from the other within the confines of the Hydra itself, it would also tell us the level of noise suppression that the unit is capable of providing for the incoming AC too. I hope that i'm clear enough in my explanation as to the type of info that i'm looking for.

Thanks again for the timely response and looking forward to any further info you would like to provide. Sean
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Kana813: Parallel line filters, when properly designed, can offer a pretty amazing amount of noise suppression / absorption. As such, i'm not discounting that they can provide a measurable amount of crosstalk rejection. Having said that, i'm just not sure of the quantity or consistency across the frequency range that this design can achieve. That's why i'm looking forward to seeing some real spec's from Shunyata. Sean
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Dear Yada : )

If you've got an open outlet with enough room to plug in a "wall wart" sized device, simply pick up an Audioprism Quiet Line and do that. If you have an open outlet but don't have the space for the "wall wart" sized device, try using an Enacomm AC line filter. This is a two pronged power plug with a very short length of power cord wired inside of a small metal can that houses a parallel line filter. I've not compared the efficiency / absorption ratios of these two devices, but i do know that they definitely lower the noise floor of the AC branch that they are plugged into. I suggested the Audioprism first over the Enacomm as they are both easier to find and far less costly. Sean
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Yada: Your electrician is probably going to be clueless in this regards. It will be up to you and the amount of research that you do on the subject as to who well your electrical system works. Most electricians only understand voltage & current demands, suitable gauges of wire, safety factors / legalities and getting the circuit from point A to point B. Unless you are lucky enough to have an electrician that is both an avid audiophile and reader of forums like these, you'll need to do your own looking, checking and designing. As such, look at some of the pic's and info available in the archives here and start taking notes. Sean
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