Power isolation / filtration?

I hope this is in the right section, but please let me know if it is not.

I recently built a dream hifi for my wife and I, for our 10th wedding anniversary. Spent years speccing these components out, thinking about it all, and hoping I did not make any errors in the build.

-Marantz model 30 2 channel amp
-Marantz SACD 30n disk player + HEOS streamer
-pair of Klipsch rp8000f floorstanding
-audioquest evergreen cables
-Audio Technica + Drop VTA Carbon turntable
-audioquest powerquest 3 power protection / filter

The system is literally a dream come true for us, and has elevated everything we listen to. The music that comes out of this thing is gorgeous. But…

The house we rent is newish(2004) but the prior tenants may have damaged the internal electrical circuits. We notice black scoring marks on some outlets in some rooms, and some sockets don’t work. Landlord doesn’t know anything…

We also have a pair of Klipsch The Sixes (powered reference / monitor) that are not plugged into any power protection or filter other than a good strip. That speaker set picks up very slight DC hum from the fridge compressor. I can remove all sources and the hum is still there, showing it’s common interference.

The big problem: the Marantz model 30 has randomly gone into protection mode 3x in the last 30 days or so. To clear it you have to power everything down, disconnect wall power, wait 10 seconds, reconnect. An amber flashing light on the amp tells me it was protection mode.

I have removed all sources from the amp other than the paired SACD 30n, which is connected to the same audioquest power protection unit and the same wall outlet. Both units are connected to the “high current / amp” sockets on the audioquest. The only other source connected was a tv, which was wired into the RCA ins on the SACD/streamer/receiver unit. I removed that, and still the issue persists…

I want to pick up a really solid isolating transformer, UPS/power conditioner of some sort, but I am overwhelmed with the selection and wide range of quality found online. Does anybody have any experience with cleaning up dirty power using full isolation transformers or UPS? The audioquest powerquest 3 is supposed to reduce ground loop noise, common mode noise, RF, etc, but something is getting through. The Marantz gear is brand new and I’ve made sure wiring is good, cables are not run on top of any other unshielded cables or power supplies, and I’ve checked and re-checked everything. The circuit this is connected to is lightly used, with only a tv, lights, and bathroom ceiling fans connected to it.

Do you use filters/conditioners, isolators, UPS? If so, do you have any recommendations? I’m not even sure my budget right now, but am willing to spend a little to make this right.

could also be picking up noise from your source gear if you could test it with like a 3.5 to rca from a phone and see if the noise is gone

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I have removed all source gear, on both speaker systems, at least once during testing.

I also have a Klipsch powered sub, and it does the same thing when it’s plugged in by itself. The Klipsch gear “bumps” when you power on or off. So does The Sixes, also by themselves with no source. Bad/faulty ground in house power?

The Marantz on the power filtration makes no bump, buzz, or hum. But it has gone into power protection mode 3x when 1) a tv was connected, 2) SACD 30n connected.

I’ve removed the TV and the only thing still connected to the model 30 amp is the paired SACD 30n disk player/streaming DAC. Both marantz devices are on the same power conditioner, same wall socket.

And sadly I have no multimeter. : ( I’m surprised someone hasn’t yelled at me for that yet lol. Had one but lost it many years ago, and I’m more of a low voltage(PC / network / sysadmin) guy myself. I don’t trust myself with buying one and trying to figure this out, so I’m hoping to acquire a UPS/conditioner with voltage meter onboard, or something.

I’m hoping to find someone who has a nice power conditioner / UPS they can give me some feedback on.

So, after a few more hours of research I may go with this device. I’ve learned even more about the source of noise on your average city electrical grid (it varies city by city, also by time of day, and of course your internal house circuit), and I really feel like a full isolation transformer is the only way to do this. This will also go with me to any new home we go to, and should resolve nearly any “normal” electrical noise.

Anyone have any experience with anything in this range?

EDIT: we bought it, and it will arrive in a few days. I will certainly come back and give as much feedback as possible after I install it.


Oh my gawd…

Received the Furman today, and finished installing and rewiring everything 30 minutes ago. I’ve spent the last 30 minutes with my mind blown.

The Furman IT-reference 15i is a monster, and it literally… improved the high frequency response coming from our Marantz hifi by, I would say, about 25% above where it was. What I mean is, the cleanliness and high fidelity imaging of the sound, the total silence of the system when stopped/paused or between tracks, the increased textures and ambience, a harder, more punchy bass response, and omg the high frequencies!!! I can hear delicate, nearly silent background sounds clearly which I couldnt hear before.

Even though my wife and I spent $$$ on the Marantz and speakers, we… missed the power filtering/isolation solution we should have had from the start. The model 30 + SACD 30n sound AMAZING plugged directly into the wall, and if we had never seen a “protection mode” fault on the model 30, we likely would have never purchased something like this Furman! We would have missed out on the increased performance and crystal clear image!

I am stunned. Obviously house power / city power grid is dirty, and I would not have known this without isolation and conditioning. Success!!! :grin::grin:

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glad that kind of money actually brought an improvement

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I was hoping to hear feedback from someone with experience with a conditioner or isolator before throwing down the $$ but I couldnt get that from vendors, forums, or anywhere, and I had to solve the protection mode problem (I believe it was a ground loop), so we just said eff it and took the plunge.

I mean, I read some reviews under the vendor websites and customers said “wow!! This improved my sound!” But I assumed I was reading at least some biased, possibly shill comments lol. This is no joke - unless you have perfect city power, you can probably benefit (at the hifi amp level, hifi preamp, etc) from something like this.

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I was pretty surprised with the benifits of installing an isolation transformer + ps audio power plants in mostly all my systems, can really help depending on where you live, glad you are enjoying the furman, haven’t seen much feedback on that model so it’s nice to see it’s legit

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We just looked up PS Audio device and daaaamn those are also high end, industrial grade power supplies / filters / isolators! We didn’t even see that brand when looking.

We started out looking at TrippLite medical grade isolation transformers, which are MUCH cheaper than Furman or PS Audio($600-1000 range), but we learned that they have a pretty loud transformer in them and they don’t filter anywhere as well as devices like the Furman, and they also get hot. Last thing we want is a hot, noisy transformer that can still allow electrical noise & cannot handle high amp spikes sitting next to our rack.

The Furman is awesome, it’s 100% silent, and it is cold to the touch under the max load we can throw at it. Furman claims nearly zero maintenance and no wearable parts to break down, so it should be a lifetime purchase. Yeah we are pretty happy!! This is basically my life’s work, other than building a family. :grin:

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is there any kind of regenerators or anything in the mortal realms that do a decent job for power?

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Not from my experience no, I’d rather be straight into the wall than a cheap conditioner, and I have yet to find an inexpensive regenerator, good power stuff is expensive it seems lol

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From what I can gather, Core Power Technologies makes a fine unit that won’t break the bank. 1KW+ units start at about a grand and can support 6 devices. Not too bad.

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