Room Treaments - Where To Begin...

Straightforward, easy to read: https://www.getbettersound.com/

surfmuz,

  There may be a splitting of hairs here. Let's ask the OP to be more exact about the question or provide more information pertaining to his situation.

 I do see the relevance of your response, as some do want to 'insulate' their listening experience from nearby neighbors.

It helps to keep in mind that speaker placement is a huge part of overall room acoustics. As you place speakers, the mid and side channels of stereo (the sounds that make stereo, "stereo") in most cases radiates strongly at side angles and not straight ahead. (Which is why "perfectly symmetrical" is NOT always ideal, based on your room interactions.) This is also why ideal placement can be elusive. Placement is super critical. You may have speakers positioned perfectly for the in phase L and R channels (imaging) and completely wrong for the mid and side signals. Speaker angles and placement is just as important to room interaction (maybe more) as any treatments. 

50% of the sound you hear is the room and electrical quality. I say that because up to the sheetrock the only thing behind it, is electrical. From the sheetrock out is the actual space. You're going to find that most of what is behind sheetrock is for soundproofing and being a good neighbor. It has little to do with room acoustics. If the room is air tight it is air tight. I like a ported room and the ability vent the room for higher SPL.

Add as much acoustic treatment as you can stand and add your subs. Tune them in . NO MAINS. Now add your mains. (I don't mean remove them from the room either. Just turn them off for sub set up). Now add the mains. Place them, get it right too. Get a tape measure and green painters tape. When your done. DECOUPLE all the speakers and be amazed. Spring, Pods, Air, innertubes, levitation, I don't care.. Decouple all the subs and main speakers. 

By treating the room and addressing vibration control. 50-60% of the sound you hear is pretty clean. LOW distortion. Tweak away... The other 40-50% is recording, source, amps, cables and speakers.

There I said something worth a crap.. :-)

Merry Christmas

Regards

Appreciate your insight. Excuse my lack of knowledge, but if my speakers (Spendor D9.2) are base spiked to carpet, aren’t they already effectively isolated?

No. Not at all. Not that a lot of people haven’t been misinformed into thinking this. The most common false narrative is that a spike is a kind of diode. Or it couples. The people pushing these ideas never can keep it straight and are immune to the illogic of their mutually exclusive theories.

I know this very well by the way having been one of them, thoroughly indoctrinated in this nonsense until the reality of it being BS was proven false by some very profound and obvious listening tests.

Isolation is pretty much only accomplished by springs. Been used in industry, science, engineering, now audio. Not just any springs however. We had one of the biggest loons in the field here hawking "super stiff springs" that were way to stiff to work properly. Consequently giving springs a bad name. Which was his goal. Everything he did was intended to screw with audiophiles.

Anyway, point is springs in order to work properly must be sized to the load. Ideally they will allow free movement in all planes and at a fundamental resonance of about 4Hz. Below that and vibrations will be transmitted to the component, but it won’t matter because only really large amplitude matter then and we don’t hear that low anyway. Above that where we do hear with great sensitivity springs filter vibrations, a lot.

So the trick is to use springs just stiff enough to result in the component bouncing on them at about 4Hz. This is effective isolation.

What happens then is the component still generates its own internal vibrations. But now the only thing vibrating is the component. So vibrations dissipate and die much faster. The result is easy to hear. Lower background noise for blacker background, and much greater detail, together creates a sense of improved dynamics.

On spikes what happens is the component vibrates, the spikes transmit this into the floor or shelf, which now that is vibrating, and like a bell rings right back into the component. Also vibrations travel all through the floor, up the walls to the ceiling, up the rack to the turntable or DAC, tube amp- all adversely affected.

Real easy to get a set of Nobsound springs, only $30, prove it to yourself. Which is what I did. Way better than anything else you will find, at least until you get up to Townshend which are a lot better but also a lot more expensive. Worth it. I always recommend try and learn cheap, proof of concept, then once you know what you’re doing go big if you want big. But you will be surprised how much improvement you will get from a couple sets of Nobsound. Then if you go Townshend, wow, whole other level.

Here's a quick demo using a seismograph showing how speaker energy that goes into the floor comes right back up into the speaker. Notice this is on a concrete floor. So much for the idea concrete is the answer!