Just discovered this thread and thought I'd share a breakthrough tweak I did a while back.
In the past I've tried some DYI isolation feet, as I did not want to spend money on something that may not work. Took an old mousepad and cut it up, putting small bits under the feet of my DAC, amp, etc. At that point I did not know that DACs or CD players benefited most from isolation. The tweak did not seem to do much but add another layer of coloration on top of the sound that was not pleasing.
I stumbled upon a site that had a pretty nifty DYI tweak that would cost less than $5. It involved wooden boards, ball bearings, tire inner tubes, and easter egg holders. Sounds silly, but I'm always up for an experiment, it's what makes this hobby fun.
I did not know where to find easter egg holders, so I looked online. Amazon had some so I ordered a few. Knowing it would take a few days for them to arrive, I got antsy and decided to get even more DYI. My local Home Depot had plenty of ball bearings, and I took the skinny inner tubes out of an old bike I had laying around. In place of the easter egg holders, I took a bunch of clothespins, removed the metal springs and then glued the two pieces back together.
This allowed the clothespin to be placed on a surface without tipping to one side, and a hole for the ball bearing to rest in.
I have a CD player, Schiit Jountheim amp, Modi multibit DAC and a power conditioner that everything is plugged into. At first I thought I would use the vibration control on everything, so I made 12 clothespin holders, 3 for each component in an equilateral triangle configuration.
The site said to inflate the inner tubes just a little bit, just enough for the component to not be resting on the surface of your rack or table or wherever it was. I did not know what level to inflate the tubes, so I had to use my ears and try different levels until I found what sounded best.
I inflated the inner tubes, took some wooden boards I had inside of a cabinet, and put the board on top of the inner tube. I then put the clothespin holders with ball bearings in an equilateral triangle configuration by measuring using measuring tape and drawing dots for each spot. That way I knew they were equidistant from each other. Rested the component on top.
Initially I did just the CD player so I could hear any slight or dramatic change in sound, to see if it worked with the individual component.
I wasn't sure what I was expecting. I think I expected some kind of change, but nothing worth getting excited about. I was not prepared for what I heard. There was an instant veil of artificiality removed. What I was left with was pure realism. Now, before the tweak I would not say the sound was artificial. But audio works in subtle degrees... and people are very often not aware of what they're missing, because everything sounds good until you hear something better. This is why upgraditis is a thing in the audio community. People are obsessed with greater and greater components because they know these subtle but powerful changes improve their listening experience.
I was beyond pleased with the change in isolating the CD player. I messed around with the level of air in the inner tube, and found a level just right and marked it on the piece of paper vertically lined up with the board. Too much air, and the midrange became bloated... not enough air and the sound did not change much.
Next I tried the DAC (modi multibit). The multibit Schiit DACs are known for their realism. And as I said before, before I did the tweak, I would not say my system did not sound realistic. It did. But I was not prepared for how much a veil there was over the sound until I isolated the CD player. This effect of pure realism was even more pronounced when I isolated the DAC. It was if I could close my eyes, reach out and touch the performers. I could now hear people breathing into their instruments instead of just hearing the instrument. I could hear the throaty rasps of singers. I could hear noises on a classical music stage I hadn't hear before (creaking chairs, machine hum from the recording equipment, etc). I could hear the acoustic resonance properties of instruments echoing through the recording space, giving me a better sense of the environment. The speed of transient attacks increased to the point of no "hang time". Pianos, violins, cellos, trumpets, etc... all sounded totally real and without the qualities one uses to describe a particular component. What I mean is, when people review audio equipment, they usually talk about its properties, such as speed, transparency, detail, etc... with these tweaks, those limiting terms disappeared, as the sound was so realistic it would be like going to a concert and describing the speed or transient attack of the orchestra... no one would do that because it is live, right in front of them, and totally real. The need to describe technicalities vanished and there was just...the music. I only use technical descriptions here to give an idea of the change. Soundstage also greatly increased in both width, height and depth, as well as "air"... you could feel the air in the room and the music bouncing through it, not just sounds coming out of nothing.
Eventually I tried isolating the amp and power conditioner, but I found, while at first there seemed be positive change, it was in fact negative. The sound became too "floaty" and strangely untethered. When I got the easter egg holders in the mail, I swapped the clothespins for them, but I found I did not like the sound the egg holders produced... too floaty. The clothespins actually gave the sound weight and anchored it to a greater degree. So it's a good thing I got antsy and impatient.
Here is a photo of the final configuration.