Haha… if it keeps others out of the room, then double duty as guards and music playback it is!
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Please what’s the Nagra power amplifier out to drive the Wilson Audio and how does it sound?
I did a thing…
I’ve been wanting to put some gear on the side wall (if not all of it at some point minus the amp and TV). When we first moved in to the new house, I tried this setup but kept getting a bunch of buzzing coming through the speakers clearly heard at the listening seat even though I’m running fully balanced, using two pairs of pro-grade Pig Hog 30 ft XLR cables. Not being able to solve the issue, I just put everything on the front wall using standard 1 meter Nordost and Wireworld XLRS. Even then, when getting up close to the tweeters, you could still a very slight buzzing coming through.
Well yesterday, I tried moving things around again and stripped the system down to only the preamp, amps and speakers. Again, I had the buzz. I tried different wall outlets, and even lifted the ground on one end or both ends with no effect.
I swapped the Schiit Freya+ for my Topping A90 headphone amp which is also fully balanced and can be switched over to preamp only mode. Tried that and I still had the buzz coming through the system, so moved the Freya+ back into the system. As a last ditch effort, I pulled the NuPrime STA-9 amps and put my Emotiva XPA-2 Gen 2 amp into the mix. The result?.. Pure silence! I mean pure silence as in I had to double check to make sure I actually had the speakers connected to the amp! No buzz, no hum, no hiss, no nothing! And that’s with my ears right up against the tweeters practically!
I connected the Bifrost 2 DAC with another pair of Pig Hog 30 ft XLR’s, still no noise. Connected the Sony Blu-ray, the Raspberry Pi4, the Roku Ultra, the TV, powered everything up… Still completely silent!
So it seems that either the balanced inputs on the NuPrime amps aren’t wired correctly, or they are not differential inputs, OR they are not true balanced inputs at all. Either way, they are out of the system, the Emotiva is back in the system. And being able to hear both amps in the same room and system configuration, surprisingly the Emotiva has more and tighter bass (had to turn the gains down a touch on the subs), a more refined top end while remaining airy and spacious, and an ever so slightly fuller midrange. Imaging seems to be about the same, though stage depth and width is a little better. BTW, the Emotiva amp does in fact utilize true balanced differential inputs.
Who knew that Emotiva was able to create an amplifier (a massive 75 pound amplifier I might add) that is capable of exceeding the performance of a pair of amplifiers at double to price (two amps). The NuPrime STA-9’s were $900 each new, the Emotiva XPA-2 Gen 2 was also $900 new.
Anywho, on with some pics…
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Nice setup and some good diagnostic work there to get to the perfectly sounding system
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One question. I know you rotate your speakers quite a bit. Was that buzz the same on all the speakers or was there a difference based on their sensitivity. Thise open baffle speakers I would think a much higher sensitivity than your Monitor Audio.
No, the buzz was pretty much the same on both pairs of speakers. The Monitor Audio’s are 90 dB, these GR-Research’s are I think 92 dB.
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A few more pics from this morning…
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Are you certain the system isn’t being subjected to ground loop hum?
Did you not read my post?
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I skimmed over it… was trying to offer you some quick help. Cheers and have a nice day.
it probably was / is a bit of a ground loop, but seems inside the amp. which says bad diode or something. or poor design. also, balanced cabling/connections everywhere is good for eliminating ‘noise’, but counting on balanced interconnects to eliminate ground hum is not a good idea. it should be mainly used for reducing induced noise on long runs of wire, not making up for poor system architecture. if a particular component is allowing a voltage potential on the ground… it should be fixed, not ‘balanced’. imo. also, not casting aspersion on your ‘system’ or knowledge, just putting a generic point out there. ground loops can be a son of a bitch, no doubt.
Good electrical signal design and high end audio components don’t always go together. And as stated above the hum could very well be the result of a faulty diode, transistor, capacitor etc. The NuPrimes may need a visit to the test bench.
Sorry, the following will be OT, so you may just scroll along…but I felt compelled to intersperse some technicalities to get the frame square again…
It needs true balanced circuitry actually, and bespoke Amps aren’t balanced, but single ended internally - oh well…
Technically, with true balanced signal topology, any common mode interference in the signal transmission is vastly reduced.
Also, current flow due to voltage potential differences between chassis grounds can’t influence the actual audio signal because it’s return path is through the inverted channel and not signal ground (as it’s the case with single ended design).
And it’s always a voltage potential between at least two components causing a ground loop.
Of course, bad circuit design might also cause parasitic interference to be audible.
And to top it off, hum is usually magnetically induced, so using balanced or single ended topology makes no difference - ground loops are rather typified by a buzz, though…
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Damn, i heard Sony wants to make it roon ready next week 
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uh, yeah, i know all that. point is. well. i made my point. which still stands. thx
Blasphemy! and don’t tell my wife. 
HA!
Looking good. And, yes, nothing like a nice trip to the audio store to remind us how good our systems already are.
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No ground loops, no “hum”, no bad diodes or other components. Both NuPrime amps were effected, not just one of them, both getting power and ground from the same source. Even had the entire system connected to the same power source just as a test. Absolutely nothing to do with ground loops or faulty equipment.
This isn’t my first system. I’ve been messing with this stuff for over 30 years. And I was not attempting to solve a problem by going to balanced. It has always been balanced no matter what.
Anyway, enough of that…
It’s been a while since I’ve posted to this thread, and nearly everything in the Loft has changed, so I thought I’d snap new photos and share. The Loft is the only room on the 4th floor of our house. It’s 15.5 x 10.1 ft with an 8 ft ceiling, and back half of the left-hand side is open to the floor below. As such, it’s mostly symmetrical above the transition frequency but asymmetrical as far as bass is concerned. Fortunately, I’ve been able to use Acourate to resolve the phase issues in the low bass, and as a result, the soundstage is beautifully balanced.
I’ve downsized both the loudspeakers and components over the years, going from Legacy Audio FOCUS SE towers, which were way too large for the room, to Fritz Carrera 7 BE monitors. My only source is a Gustard X16 DAC, fed by VitOS for RPi4 network audio transport. The RPi4 is powered by an Allo Shanti LPS. A Topping Pre90 preamp routes the signal to dual SVS 3000 Micro subs and Orchard Audio monoblock amps. Cables are mostly from Straight Wire, and I’m using a number of iFi Audio power products, including their PowerStation. Isolation products are from Herbie’s Audio Lab. Room treatments are from ATS Acoustics and GIK Acoustics.
Now, time for some photos:
You may notice a laptop on the floor in that last photo. It’s not normally there. I just use it for taking measurements with REW and building filters with Acourate. Since Acourate v2 was just released this weekend, that’s my project for this afternoon. My normal playback control is the delightful rooDial, which helps me to not get distracted by my smartphone when I’m trying to unwind by listening to music. Highly recommended.
Thanks for having a look, and happy listening. Cheers.
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Very nice setup! I was wondering, how did you connect the Pre90 to the SVS subs? Thanks!
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Jim is that the Bose 700 soundbar and bass module? Nice! Do you have the surrounds too? Regards, Dave