Concur, and very clever to strip away the bells and whistles which will likely degrade the sound. I‘m likely to go with a couple of lower-power BITs, one for each front end component. With two high-current duplexes on each of my two P20s, that’s eight AC outlets - plenty, six left, after two for my monoblocks, the JRDG 725S2s. Are your monoblocks particularly power-hungry, or noisy? I’m considering auditioning the new generation of class-D amps from Merrill Audio with Gallium Nitride transistors.
Meant to mention: I did blow a P10 fuse when I accidentally turned on the BIT with P10 already on. You MUST connect the BIT to the high current outlets and use the PP on/off.
My power amps are Parasound JC1s. They do not seem compatible with regenerators. Although I don’t consider my power to be noisy, the BITs improved power amp SQ.
Jhnh,
Excellent monoblock amps, the Parasounds - the newest version was recently reviewed in Stereophile. Did you find that your 1,800W ExactPower BITs consumed (heat-dissipated) between 2-3% of their rated capacity (36-54W) when idling, even with nothing was plugged in? I’m likely buying two units of the PLiXiR Elite BAC 400s, with both to be plugged into one of my P20s. They’re supposed to have better than a 1.5% idling consumption (leakage/loss).
Question for the EEs:
What’s the purpose of a shunt capacitor on the output of a balanced isolation transformer (across +60 and -60, no ground)?
I do not know what idling consumption Is, but the BITs do not generate any noticeable heat
Perhaps because of primary purpose and use of iso transformers - connecting and disconnecting devices from the secondary, preventing any inductive voltage spikes. Could achieve same connecting to ground, but then would need 2 capacitors, 1 is cheaper and achieves same.
Idling consumption - using the front panel display of the P20s, I’ve measured and tracked each and every one of my audio components, so I was just curious about the BITs.
AC regenerators (essentially power amplifiers) do many wonderful things, exactly as claimed, in the area of delivering clean and pure low-impedance, high power AC - up to a certain point, constrained by its rated output. Not to nit-pick, but I’d like to better understand its less-well-understood shortcomings.
As I had suspected, while reduction of both common-mode and differential-mode noise is “spectacular” up to the AC regenerator’s upper bandwidth, above this, which is to say, unfortunately, the VAST majority of AC and RF noise, pass RIGHT through to the AC regenerator’s outputs. Additionally, noise on the Ground line is not attenuated at all by the AC regenerator, which would be especially problematic for source components.
Hence, a BIT (balanced isolation transformer) connected between the AC regenerator’s output and the source component will be complimentary, as it will be remove AC noise (both common-mode and differential) all the way up to the RF spectrum, as well as noise on the Ground conductor/plug. The weakness of the BIT will be in its high AC resistance, due to phase lag for AC transients, hence unsuitable for supplying AC to power amps.
Here’s an excellent White Paper published by Garth Powell (of AudioQuest) from where I extracted my observations from:
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I am interested what regenerators were studied for the white paper. Are we talking the previous generation P5/P10 or is this going way back. What changes have happened With more modern regenerators that may improve performance?
Are there any opportunities for a parallel device to the regenerators to tackle other noise issues like the ground noise?
None that I am aware of that actually do anything.
PSA regenerators seem to work on different principle to those covered in the whitepaper - from what I could understand, PPs only do active “corrections” to the power supply entering them. Perhaps what is covered in the whitepaper applies to those corrections only.
My understanding is that the current generation of Perfectwave AC regenerators are essentially the same as Class A/B amps, enhanced in the areas of higher efficiency, output power, lower output impedance, and more accurate AC waveform shaped by DSD, but bound by the same constraints relating to Ground noise and RF noise presence and pass-through.
So I have a PP3 on the way and am super excited to hear it, but also a little perplexed having just read this thread. Is the PS Audio claim that PowerPlants “reduce noise and THD to virtually zero” true or not? Or does that claim just refer to a certain frequency spectrum (not RF)? But if that’s the case, does it make sense to compare it to other power conditioners that “only affect a portion of incoming noise”?
The only explanation I’ve found on this thread is that “all amplifiers produce noise”. OK, that’s fair, but still al little hard to accept given the claim that noise is reduced to virtually zero.
Seems that either the OP’s measurements are wrong or irrelevant, or the PS audio claims are overstated. Ultimately, I’m going to let my ears judge the value of the device, but like to know what the unit actually can and can’t do in terms of its ability to reduce/introduce noise. Would love it if someone from the company could provide a little clarity.
The Power Plants (especially the current crop) do a LOT of things really well, and sound wonderful - I’m a happy owner of two P20s. I didn’t want to turn a zit into a mole hill, but simply wanted to better understand the arcane subject of RF noise in both the Ground line, as well as its residuals present in the regenerated AC. It really all boils down to the amount and audibility of the noise - the name of the game really is the degree of asymmetrical balance between audible benefits (positive) vs cost and potential trade-offs (negatives).
My assertion is that eliminating the RF noise typically present in abundance on the Ground line is critically important, and my hypothesis is that a well-designed BIT will help do this and hence be complementary to the Poweplants. Accordingly, I’ve bought a few BITs for my front-end components, and I’ll get to audition the combo in a month or two.
This is exactly why I prefer a commercial grade mission critical “online” UPS system. The only one I recommend as of now is the Eaton 9PX series. It has none of these issues and no issues whatsoever. Just 100% pure energy. Do not cheap out and get something else thinking it is the same. It is not.
You just need to choose what size you need. If you require a very large size this could entail having an electrician install up to a 30 amp dedicated branch. Do not mess with it. It is lethal… You or a shop will also need to install a quieter/ higher CFM fan and a high end power cable of your choosing. Be aware you will be cutting off the termination on the power cable. So make sure that it is of non proprietary design. This is the only 100% clean power in existence.
So much so that a company relabels it for sale to Audiophiles “loaded” at a mere $25,000. A new 9PX runs $850 to $4000 or so. Check googling CDW outlet. They often have them brand new 75% off. do not buy a used one! the batteries are probably in need of replacement and that is 80% of the price of a new one. Unless you can read a schematic and source good batteries cheap. Still, often used ones the inverter is bad. Don’t buy a used one ever.
For the record, in my reference system I run two Power Plant 20’s. they suit me fine.
I run a 9PX(modified) in my bedroom system. It is still a $600K system. It has a display just like the P20. Alas, it is indeed cleaning the power better than the P20’s. this is done simply because it is literally “off the grid”. the P20 is still on Grid. The P20 I would say is the top Audiophile power conditioner. the 9PX is little known outside of industry and Hospitals. It runs life support.
I have several threads regarding the Eaton products in this forum. Use the search if you are interested. I am in no way underselling the P20. I just said I feel that it is the best audiophile power conditioner. I am using 2 of them in my reference system and not a 9PX. Personal preference. They happen to sound better in that system. In smaller scale systems it is not nearly as noticeable as they are not nearly as resolving. A Power Plant or a 9PX are both a fine choice.
Imho, RF noise in the mains is not that of an issue. Most audio equipment connected to mains is powered via a transformer, that is designed to operate at mains frequency only. As frequency rises, it will face inefficiencies and losses and will not pass well to secondary. It then meets additional filtering, that deals with rectification and switching noises, regulation, etc. Transformers that operate at audio range and pass that frequency range are called audio transformers and cost $$$. Mains transformers are not designed for audio frequency, they don’t pass it well, nor the RF. PPs, along with some passive filtering, may do some active filtering to a certain degree, but its primary role is to drive a very low impedance circuit (milliohms, hence all the heatsinks) in order to reproduce distorted sine wave and correct jitter. RF noise is injected in different places that is outside PP control, these are circuit boards, interconnects, individual elements, long traces, etc. The rectifier bridge inside your equipment, most likely produces more noise than what comes in through mains. PPs do their role as designed, and do it very well. I wouldn’t be put off by PPs not filtering RF noise. Filtering the power rails noise in the equipment is the job of this equipment power supply unit. Also RF is anything between perhaps 20khz and Ghz, no equipment can deal with the full spectrum, only a certain part that it is sensitive to.
I’m going to chime in. I used to use BITs with my P10 to great effect. Upon buying a P3 and P12 recently, I decided to use the BITs on my power amps (previously plugged straight into the wall) — also to great effect.
I’m a BIT in a box guy — don’t want any extras. I finally found a source of a 500W BIT in a box. I put it between the P12 and my preamps (Cary SLP05 and PS phono). the Cary is notoriously oblivious to the what the Power Plant does, but responds well to balanced power.
Adding the BIT made an obvious difference: more soundstage depth, and virtually eliminated peaky artifacts (piccolos, flutes, etc.).
So, I do think a BIT is a complimentary device to a Power Plant. Just make sure the BIT has no additional filtering, which would probably be counterproductive. And not all equipment benefits, but tubes may benefit more than solid state.
Just my experience.
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WOW, the PLiXiR Elite BAC400s are by far the most cost-effective upgrades I’ve ever owned in my entire 45+ year audio career - I’ve connected two of them to the High Current duplex outlets of the Powerplant P20 to power my two MSB Select II DAC powerbases, and have been breaking them in (together with the balanced AC power cables) during the last few days. The audiophile journey of asymptotic diminishing returns… you know, painstakingly selecting main components to build a system solid enough to be start in the “high 80’s” 80’s” (relative performance, given real-world constraints in room acoustics, room volume, etc.), then celebrating when the 90 threshold is breached, only to stumble back and forth through trial and error, with each incremental gain being far more difficult than before, to finally reach a limit of say 92-93 points in one’s optimized system… well, I think my system was at 91-92 points, but the BAC400s single handedly added 10 points, just like that. Yes, my mental constraint of what I though was possible (in absolute performance) was clearly exceeded. I’ve now learned that even higher absolute performance is possible, and that the imaginary “100-point perfection” bar can actually be elevated even higher than I had imagined, thanks to the PLiXiR Elite BACs. A new journey to discovering new heights has been sparked.
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