@panzrwagn wrote:
Also, regarding high efficiency systems, they benefit greatly from being properly gain staged so that you don’t hear noise when the system is idling. Ideally, you want your preamp/line stage to clip within 3-6 db after the power amps. It’s common to see preamps operating 10-12dB or even more gain than is necessary, and that robs the system of that much dynamic range and results like hissing horns at idle. Turn the amps input sensitivity down, and drive the preamp harder. That leaves the noise levels down.
In an actively configured context - i.e.: with the driver connected directly to an amp channel sans passive XO - the issue with hissing, high efficiency mids/tweeter horns isn’t necessarily due to improper gain matching, but simply that a very high eff. speaker element of (in my case above) +110dB’s amplifies and exposes the inherent, component related noise levels upstream; even with a proper gain match as outlined by you, noise and therefore horn hiss could still very well be prevalent here.
Input gain in this case could (if possible) be lowered in an effort to quench noise, and while that would likely pose no problem with regard to not having the full power capacity at hand, at least not with very a high eff. horn/driver, changing input gain (and thereby output impedance) can affect overall sound presentation/quality and thus may come with a proviso.
That is to say: in such an (active) instance and trying to get rid of horn hiss the outcome could actually be one of an inverse scenario where input gain must be set too low (i.e.: not properly balanced wrt. input/output) to compensate for an exposed, inherent noise level upstream - not that it might be a problem SQ-wise to do that.
Quite a few pro power amps have output volume controls for each channel, and if such an amp were to be used on a mids/tweeter horn actively, ameliorating noise from upstream could be done via volume controls here as well, but those also seem to have some impact on SQ when attenuated.
If on the other hand a passively configured high eff. speaker system has an issue with horn hiss, I would be inclined to take a closer look at the gain structure in addition to the S/N ratio of the components used.
So, any impeding the dynamic range of a properly gained, actively configured high eff. speaker setup comes down to where the noise floor sits and its origins here, be that either S/N ratio or mechanically induced noise from amp fans or other external sources of noise.
@ghdprentice wrote:
Thinking further along the line of low levels of background noise, I dawns on me that different systems have different presentations of low level detail. I am thinking of the recording venue. Let’s assume a symphony hall for the moment.
I used to listen at the symphony to just the reflections of the sounds. So, if the violas would abruptly start playing I could hear the sound reflect off the sides of stage left, then the ceiling and then blend from the same sounds reflecting at the back of stage. These are pretty sublet and only a small number of db above background.
Not quite sure I follow here. How would you "isolate" the reflections of sound in a symphony hall to that of its perceived totality, other than focusing on the reverberative nature of a venue and try to assess the decay time by ear?
One my major realizations were that many systems overemphasize the venue of the recording. So say these reflections were 5db above the background… my current system would represent them as about 5db. But a lot of systems… my last generation included would represent them as 10db above the background. This is what I consider details forward. An overemphasis on quiet detail. Thirty years ago, I would have chosen this as “better sounding”.
The source material dictates the "venue" and the overall nature of the recording, and of course from hereon acoustics and speakers in particular affects what’s received by the ears. If by "systems" you include acoustics of a given listening environment, then it makes a little more sense to me, but looking at the gear isolated I fail to see how it can manipulate the "venue effect" or lack thereof to the degree you claim or propose. Also your described XX dB’s "above the background" seems dubious to me. How would you quantify and arrive at those 5 or 10dB numbers?
My thought is that these two systems would sound very different in rooms with different background noise levels.
Different background noise levels would affect low level detail, perceived dynamic range and image focus in particular, but what distinguishes those two systems to begin with?
Assuming the same character of sound in a noisier room, one would probably identify the 10db venue as better balanced because the details would not be drowned out. One more variable in evaluating systems.
Sorry, I fail to understand this.
Better and better equipment tends to get better at presenting all sounds proportionally (I think… assume.. in general). So if you don’t make sure your audio environment is up to the challenge, you could be losing a lot.
From what I believe you’re going at here, my take is acoustics (incl. noise floor) and the speakers are the most important factors - much more so anyway than amps and source. As an example cross-over design choices can have speakers emphasize spatial aspects, but hardly significantly modify the nature of the recorded material you seem to propose wrt. "venue." It’s really about the implementation of the specific speaker design in conjunction with the acoustics that sets the bar most predominantly, at least from my chair. "Better and better gear" is the least of it, if anything that really affects proportionality in reproduction.
Maybe by accident, I have worked at more and more aspects of sound as my system has improved… so I now have the best quietest audio room I have ever owned.
That’s certainly what matters, kudos - whatever the reasons for the improvements are in your case.
Sorry for the lengthy post.
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Wow, two 600 watts mono for $900. $1.5 per watt, much more value for money than the basic model A2 ($3.1 per watt). Double the wattage of the current HC-1 mono model ($5.9 per watt) from factory. Good buy, Mike. If I run into that deal at that time, I would have my dream speakers Vandersteen 3A signature, which is seldom mentioned in this forum but one of the best sounding speakers to my personal taste. Enjoy.
CJ
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Hi, Mike
The 1st image is from the most economical amp BasX A2m. (50 wpc into 8 ohm for $350; class A/B). The 2nd image is from BasX A2 (160 wpc into 8 ohm for $500; again class AB) which I was interested but turned away because of the internal fans). If my memory serves well, the price was even cheaper before. I called the company to confirm and ask the sales if the fan noise can be heard. Of course, during the playback you do not (go figure) but how about when the music quiet down? I am not sure for their higher end models XPA series because the stock pictures do not show. You could call Emotiva to find out if interested.
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@lanx0003 Wrote:
A well designed amplifier should not rely on both heatsink and fans for thermo control even Class A. When I see an amplifier has heatsink but is still equipped with fans like Emotiva or Crown, I will turn away immediately even the price point is attractive and even the saleman / reviewers tell me you will probably not hear them.
What Emotiva amp do you own that has a fan for cooling.
Mike
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I guess the best solution to avoid the fan noise from the amp is don’t buy them. Keeping the working temperature under control for an amplifier and prevent it from overheating is part of design process. A well designed amplifier should not rely on both heatsink and fans for thermo control even Class A. When I see an amplifier has heatsink but is still equipped with fans like Emotiva or Crown, I will turn away immediately even the price point is attractive and even the saleman / reviewers tell me you will probably not hear them.
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Thinking further along the line of low levels of background noise, I dawns on me that different systems have different presentations of low level detail. I am thinking of the recording venue. Let’s assume a symphony hall for the moment.
I used to listen at the symphony to just the reflections of the sounds. So, if the violas would abruptly start playing I could hear the sound reflect off the sides of stage left, then the ceiling and then blend from the same sounds reflecting at the back of stage. These are pretty sublet and only a small number of db above background.
One my major realizations were that many systems overemphasize the venue of the recording. So say these reflections were 5db above the background… my current system would represent them as about 5db. But a lot of systems… my last generation included would represent them as 10db above the background. This is what I consider details forward. An overemphasis on quiet detail. Thirty years ago, I would have chosen this as “better sounding”.
My thought is that these two systems would sound very different in rooms with different background noise levels. Assuming the same character of sound in a noisier room, one would probably identify the 10db venue as better balanced because the details would not be drowned out. One more variable in evaluating systems.
Better and better equipment tends to get better at presenting all sounds proportionally (I think… assume.. in general). So if you don’t make sure your audio environment is up to the challenge, you could be losing a lot. Maybe by accident, I have worked at more and more aspects of sound as my system has improved… so I now have the best quietest audio room I have ever owned.
I am not adding, change volume… because that adds a bunch of additional variables.
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Boxcarman: Absolutely brilliant. It's nice to know vaudeville is still alive!
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Thanks for your thoughtful comments @snilf. On your father and background noise. I struggled with ADHD through school until I was around 30. I did not know I had it… but I could not concentrate… nearly flunking out of college more than once. I noticed sometimes if I studied in the Student union cafeteria I could concentrate for a while… all the talking would become background noise and suddenly I could study. Many times it would not work. For much of my life I just thought I was stupid… that was my fathers belief.
I found that being in exceptional shape (massive amounts of daily exercise) also allowed my mind to concentrate. I figured this out in my early 30’s. Then I went to graduat school where I graduated near the top of my class. I figured out that I had ADHD while in my mid 40’s. Confirmed by my doctor when I was 60. Maybe your dad had a little AD.
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Great thread; thanks, ghdprentice! I’ve got several things to say here.
First, I completely agree that ambient noise is almost surely a far bigger problem for most high-end systems than any less-than-optimal component. It’s at least as important as room acoustics and proper speaker positioning. In my previous house, when I had to buy a new fridge, my first criterion: how quiet the damn thing was. This always amused salesmen. Now, I’m lucky; the house is big, the kitchen is two rooms (and walls) away, and my listening room is very quiet. So quiet, that the slight hum my old amplifier’s transformer has developed bugs me. I’ve tried many strategies to resolve this, some of them discussed, or learned about, on this forum (e.g., a varnish "dip-and-bake"; you don’t want to know). Like curiousjim, I also took my unit to a very competent tech, and he couldn’t hear the hum at all. Of course, his shop was on a busy street. But I’m fanatical, I’ll admit, about creating as quiet a space as possible for listening. I think it was ghdprentice who mentioned watching a fire while listening. I’ve got a fireplace in my listening room, too, but I never do any serious listening with a fire going. The fire makes too much noise!
I’ve got a John Cage story that’s relevant here. I met him once, through my wife. He told me about having spent an hour in an anechoic chamber. He claimed that, even in "complete silence," he heard two faint sounds, one very low, one very high. He concluded the low tone was the sound of his blood coursing through his body, and the high hiss-like tone was the sound of his neural activity. But I think he just suffered from tinnitus without realizing it; there’s no way one can "hear" one’s neurons firing as a constant high-pitched hiss! Of course, John Cage was all about the impossibility of "silence," about how "music" is more a matter of the attention of the listener than the intention of a composer, so his story had a Cagian moral.
As for SPL meters, on Apple products or whatever else—you know, I suppose, that they must be properly "weighted." Most inexpensive SPL meters are "A" weighted, and meant for testing ambient noise at worksites that may be dangerous. "A" weighting cuts out at 100 Hz, if I remember correctly; it’s somewhere below which there is A LOT of musical information. If you have a meter that can switch between "C" and "A" weighting, it’s startling to do so; music that reads, say, 80 db in "A" will jump to 90 db or more in "C." And, of course, Apple products don’t prioritize the noise metering they throw into their devices. Get a proper meter if you want an accurate reading.
Regarding panzewagn’s comment about architects using HVAC and other drone noises to "create some sense of privacy"—yes, of course this seems crazy, but it may not be not quite as pointless as it seems. My dad was a Caltech scientist, and a very finicky person. We lived at the end of a private road up against the San Gabriel mountains, where it was very quiet—but not quiet enough for him! In his study, he had an old heater with a fan; the heater didn’t work, but the fan did, and he ran it all the time when he was working. He claimed that the constant droning sound distracted him from being disturbed by the occasional dog bark or distant car horn or whatever. I think I get this.
One last thing. There’s a psychoacoustic phenomenon—I forget what it’s called, but there’s a Wikipedia page about it—according to which certain low-level kinds of noise actually focus the mind’s attention on the "meaningful" sounds those noises might otherwise seem to mask or distract from. There is a theory, which makes a lot of sense to me, that this phenomenon explains why some people prefer vinyl to digital: the surface noise and the occasional pop and click, far from distracting from the music, actually provide a background against which conscious attention isolates the musical information, highlights it as it were. This could explain my dad’s practice mentioned above, but would be diametrically opposite to the preponderance of views expressed here (including my own) that serious listening demands as quiet a "noise floor" as possible. It’s one of the reasons I don’t buy into the vinyl fetish; there’s just too much scientific evidence of its irrationality, and in any case, it certainly doesn’t correspond with my own listening preferences. Most of us live in perpetually noisy environments; it is possible that, for those who do, brain "circuitry" has accommodated itself to attention against a constant background of noise, and this may be why vinyl sounds better to them. I’m lucky in that regard to live almost all the time in environments that are very close to silent.
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@ditusa I think you missed my point. That everything gets put back onto the line as noise. Also, I'm surprised a rack company has a blanket statement opinion about power conditioning. That's the first haha.
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@j-wall Wrote:
I have a small fan in my music room and when I click it on, even with the Shunyata power conditioner, you can hear the fan click on and off.
Power conditioning, see page 38 below:
Mike
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@baylinor I too suffer from tinnitus, don't really like the volume too high or it shortens my session. Don't bother calling the tinnitus hotline. They never pick up. It just keeps ringing.
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Do you think part of the this could be electronic noise being put back into the line from the unit running? I have a small fan in my music room and when I click it on, even with the Shunyata power conditioner, you can hear the fan click on and off. It's adding noise onto the line that not even my conditioner can stop. Same with my VPI 16.5, which sometimes pops through speakers when my gear is on and I activate the switch to clean a record.
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@panzrwagn Wrote:
Also, regarding high efficiency systems, they benefit greatly from being properly gain staged so that you don't hear noise when the system is idling. Ideally, you want your preamp/line stage to clip within 3-6 db after the power amps. It's common to see preamps operating 10-12dB or even more gain than is necessary, and that robs the system of that much dynamic range and results like hissing horns at idle. Turn the amps input sensitivity down, and drive the preamp harder. That leaves the noise levels down.
I agree!
Mike
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i bet the majority of y'all have perfect hearing and not a trace of tinnitus. not me. that said, i am a big believer in living out in the woods to get away from city/suburban noise. those are the big noisy dogs that, once those are out of the way, then the domestic sounds [HVAC, refrigerator, line hum] take on a much bigger presence. i have found that the best and most practical way to deal with those, is to use an audio [dynamic range] compressor on the audio, to bring up the music buried under the ambient murk. otherwise, one has no other choice but to turn up the volume and possibly [further] damage one's hearing as well as disturb the neighbors. a 90+db dynamic range is totally impractical for anybody living in any real place where the 90% can afford to live. a modest amount of dynamic range compression is useful in majority of listening environments.
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@panzrwagn
Wow, what a story. Add sound to create a sense of privacy. It is incredible what some people will come up with. I now wear my noise cancelling EarPods when I walk the dogs and go on bike rides. The lower noise level relaxes me… while the background is more or less white noise… it kind of “jacks me up”… not relaxing.
One of the most profound improvements in my professional life was getting Bose Quiet Comfort headphones (I flew over 250,000 miles a year). I would put them on when I got to the airport and take them off when I got to the hotel at my destination. Huge improvement in my life! Lowered stress. Most of the time I had nothing playing… just noise cancellation.
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As someone who did acoustical consulting, this is a favorite topic. In particular, doing battle with architects an interior designers who rely on HVAC noise and in some cases ambient noise generation to create some sense of privacy in open office environments. How anyone could believe that adding noise makes for lower stress work environments is completely beyond me. In one case the ambient level from HVAC was over 65 dBA throughout the facility, and it was billed as a 'quiet' work environment. It took over a year, dozens of employee complaints, stress related sick days, and even employees quitting before management relented and implemented my design. We reduced the ambient to below 50 dBA, and within a couple months productivity, employee satisfaction, and even attendance had improved measurably.
Also, regarding high efficiency systems, they benefit greatly from being properly gain staged so that you don't hear noise when the system is idling. Ideally, you want your preamp/line stage to clip within 3-6 db after the power amps. It's common to see preamps operating 10-12dB or even more gain than is necessary, and that robs the system of that much dynamic range and results like hissing horns at idle. Turn the amps input sensitivity down, and drive the preamp harder. That leaves the noise levels down.
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Great topic and probably the most cost effective means to improve listening sessions.
I never listen to music when others are at home. In fact I never go into the 2 channel room when my wife is around to remind me how I waste money and how ugly the bass traps are. Music above quiet levels gets up the ire of my daughters. So, not much time to listen, but when I’m alone, air filters and humidifiers get switched off and it's quiet
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One of the amps in What used to be my primary system developed a transformer hum and it drove me crazy. The amps are from the eighties and I had them serviced a few years back and I asked the tech about the hum and he said what hum? To me it’s very noticeable anywhere in the room and he had to have an ear right above the transformer to hear. Someday I have to replace that transformer (about $550) but I’m in no hurry.
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I have probably as quiet a listening room as anyone. Unfortunately the tinnitus has a way of taking over. Oh well, who said life was perfect.
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@ghdprentice wrote:
I had the same problems with the fans on my amp. While really small, I could hear them. So, I put a line of bolster pillows along the wall behind my system… problem gone. It was all reflection from the wall.
Nice solution and find. I suspect it had some, if only minor impact on the overall acoustics?
111db speakers… wow!
Only the horn/compression driver combo covering from ~600Hz on up (fed by the Belles amp) :) The bass section below is 100dB sensitive, and the subs are 97dB ditto. They're fed by a LabGruppen FP6400 and Crown K2 respectively.
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@phusis
I had the same problems with the fans on my amp. While really small, I could hear them. So, I put a line of bolster pillows along the wall behind my system… problem gone. It was all reflection from the wall.
111db speakers… wow!
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@nonoise
Ok, your user ID is taking on a meaning. I am really sorry to hear about your situation. That has got to be hard.
I actually assembled my former Office headphone system in the adjacent room in part to get away from my quiet air conditioner (in its own room, with a solid door) during the afternoon in summer. But now I can control my air conditioner from my iPhone… so I can turn it off during summer afternoon sessions.
I then upgraded my headphone system to audiophile levels. So, it is in a quiet place and offers isolation. It also allows me to watch the fire and listen to music in my library during the winter.
I really hope you can get into a quiet house soon.
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I have two background noise sources: the (low noise) fans on my LabGruppen amp, and a slight hiss coming from the EV horns that’s due to their 111dB sensitivity and being coupled directly to a Belles SA30 amp (such that noise down stream is exposed) - that is, sans any passive cross-over components in between to filter noise. Both noise sources are barely audible from the listening position, and being very low in nature and once the music (or movie) is playing, I don’t notice it. That is until I switch off my amps and music server so that the setup effectively comes to rest, and now I suddenly notice the silence (...).
I’m guessing these noise sources have some impact on my listening experience, but to which degree is up in the air; again, I’m not consciously burdened by it. One thing I can’t (or don’t want to) do anything about is the slight hissing noise coming form the horns. I could filter some noise with a capacitor in between, while also protecting the compression driver to some extend in case of a malfunction down stream, but it would also defeat the purpose of avoiding passive cross-over components to begin with (I know: dangerous living). The other noise source though from the LabGruppen amp I could potentially ameliorate with even lower noise fans. That I’m actually looking into.
At the end of the day and at present I find the background noise level from my setup to be fully acceptable, but as I outlined above some effort can be made to bring it down even further. It will be interesting to see the outcome of it.
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Ambient noise is the bane of audio listening sessions. It's why, in my crappy second floor apartment, I rarely listen in the summer when the AC is on. It's a wall unit and shares the same space as my stereo making it impossible to fully appreciate the music.
There are times when I'll go as along as two weeks without listening as it frustrates the living hell out of me. Then, when I can turn it on, the event is almost an epiphany.
I can imagine and appreciate what a junkie goes through to get that fix.
All the best,
Nonoise
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We should demand our rights for late night listening freedom 🙂
trying to have my listening sessions from 23hrs till ...power amp gets...warm enough.
Drawback is the volume, you want more.
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Even if you don’t have any SPL meters, it’s really as simple as just sitting in your listening room sweet spot, and for a few moments, listening; with no music playing. If you hear your refrigerator running, or your furnace running, or neighbors outside, or even audio equipment transformer mechanical hum; this background noise, in essence, is raising your *perceived* listening room noise floor. You may tune it out when music is playing, but it’s still there. You may find (I know I do) your listening experience, better, or improved, by trying to lower the ambient noise level in your listening area. It goes without saying that so much about achieving and reaching audio system performance nirvana is about listening - buzzes, hums, wall reflections, dead acoustics, cold acoustics, the difference in cable choices, etc. (keeping the good, while eliminating the bad). In my particular situation, my furnace and refrigerator are the loudest in my home. If I’m in a serious listening mood, and want a really quiet listening environment, I will temporarily turn them off.
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@dpop
I have also been lucky enough to experience quiet. I used to explore caves and underground mines. Frequently alone… hmm, having said that, I am thinking in retrospect that was not that safe… I did this stuff a lot. Anyway, I have always been surprised at the quiet… but that in confined areas how you can sense the walls… in big caverns the noise floor drops away. You have to hold your breath and listen of course.
I worked for high tech companies. Our office in Germany had an anechoic chamber… yeah, now that is quiet.
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@twoleftears
+1
I just remeasured the background… 25db with iPhone. It is Thursday mid morning… so, under ideal late night conditions it probably goes down a bit more, low 20’s. I then flipped on the air cleaner. My phone showed 27db… but… of course it jumps to high 30s - 40s if I take a breath. I think my conclusion is the iPhone Microphone just isn’t that sensitive in this range.
To me carefully listening, with and without the air cleaner sounds more like a 10db change (guess). I have a better SPL meter somewhere and a high quality microphone I bought for this purpose. I’ll pull them out.
BTW, three walls of my audio room (front and sides) are underground and as such help significant lower the noise floor. The distance from the speaker wall to rear wall is over 40 feet… so rear reflections are minimal.
I have always been cognizant of background noise. But, I am really surprised at the amount of special information, dynamics, and detail lost by a seemingly really small increase background noise.
Obviously, there are two things going on… your system background and ambient room background. These factors and their interplay have to be really important in results reported by lots of folks about there equipment performance.
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@twoleftears
Yes! And that n-th degree of blacker black that reviewers talk about as attributable to expensive components, doesn't matter that much if you have any significant degree of ambient noise.
You got it!
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Yes! And that n-th degree of blacker black that reviewers talk about as attributable to expensive components, doesn't matter that much if you have any significant degree of ambient noise.
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I find bad rooms and background noise don’t necessarily detract from the music but they add to the stress. You don’t realize you are working harder to listen until it’s gone.
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Ambient noise is a number one priority with me. I’ve been in some very nicely constructed radio station studios, and have been amazed at how quiet, quiet can be. There’s a radio station studio that I sometimes still step foot into, and I’m always completely blown away by how quiet it is (without question, it is the quietest place I know of on this earth). I was not involved with construction of it, but I know they went to great lengths to soundproof it - you can’t even hear the air conditioning in action. If I somehow step into a very quiet public space (like maybe a museum of some sort), my ears and brain immediately recognize this, and bask in all of its unintended glory. Many of us just don’t realize, on a daily basis, how we’re constantly bombarded with noise.
I too try and strive for quiet home listening environments, and even though I’m most times able to achieve that (thankfully most times my neighborhood is quiet too), I still prefer my headphones when critically listening. I even go a step further, and darken my listening environments. Many times I will also close my eyes when listening, and try and tune everything out, except the music I’m listening to. It’s not always easy creating a quiet home listening environment, but with all of the great sound systems many have assembled on this site, attaining an ultra-quiet listening environment should *also* be a top priority.
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ghdprentice-
I can appreciate your comments and it makes me want to ask “how low is the typical noise floor in your listening environment? I would think very low if the effects of an air cleaner made a difference from that distance.
I fight this myself since putting my equipment into a small room. The equipment (tubes) can quickly raise the temperature in this space by over 10 degrees and demands the use of air conditioning for listening periods of over an hour.
This room (when using a db meter phone app) sits at 25db with just the equipment running. That will jump to 45 with the A/C on. The airflow definitely has an effect on how I hear the music- but sometimes it becomes unbearable without it!
BTW- I like your system! A very nice setup- our systems have some similarities as we are both AR users.
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