Has there been any inexpensive item that enhanced your system's sound?


For me it was an inexpensive power cord that was laying around for years, a Pangea AC9.  I have it connected to my Yamaha A S2000.  I've tried the stock cord on the Yamaha and then some of my other cords, (Wireworld, VH Flavor 4, Acronlink/Oyaide custom cord and a MAC). I've had lots of amps and integrated amps over the years, and this is the first time the Pangea contributed to making better sound. It surprised me because I had tossed it aside and forgot about it.  Power cord performance is such a crap-shoot and dependent on so many other variables in the audio chain.  Any inexpensive item you've come across that enhanced your system's sound? 
foster_9
agriculturist84 posts05-13-2016 5:48pm"How best do you clean an AC outlet?"

Deoxit and a pipe cleaner might work inside the receptacles. I highly recommend unhooking it first, or pulling corresponding fuse. Be sure nothing gets left behind that can cause an internal arc. Otherwise the 4th of July may come a little early. I would just replace it for some cheap insurance. Unless its one of those $100,000 units. 

I discovered another inexpensive trick. Dynamat-ing the internal sides of source covers. Avoid blocking vents. I can see some potential for improvement there.  
A lot of great feedback here. For me, the best "inexpensive" tweak that I made was buying Solid Tech Feet of Silence. They were recommended to me by a high end audio dealer who actually didn't carry them. He said they will have virtually the same performance characteristics no matter what surface I place them on. He was right- and the vibration reduction markedly improved the soundstage in my system. The better news was I was able to keep the rack I was using which I find aesthetically pleasing (high WAF) and fit my application well. So, I feel like I have the best of both worlds. 

Absolutely consider smartly placed room treatments. Even "free" ones can make a significant difference. Draping a thin tapestry over my flat screen behind my system cleaned up the musical presentation dramatically! $29! As someone wrote earlier, pay attention to first-reflection points. 

Power conditioner (the right power conditioner) and power cords also made a significant impact on my system. However, I would classify them as inexpensive tweaks. 

And don't forget why started down this path in the first place... for the love of music. Cheers!

Thanks Meerzistar.  I think replacing is the best thing as you are really suggesting I think.  I did use Deoxit on all my AC cable connectors and that was a big help.  But I have so far not tried to clean the wall socket receptacles.  And listening to what you say I won't now.  Trouble is I can't replace my receptacles in my rental apartment, so doing this may have to wait.
In the late 90’s I purchased a Naim Wiremold power strip for $60.00. 9 heavy duty outlets wired in series connected by a busbar. Solid aluminum case. No lights, no fuses, no off/on button. Basically all power, no filter and a heavy duty captive grounded power cord.

Approved by and endorsed by Naim Audio to be sold by Naim Audio distributors to be used with Naim gear. Non current limiting. Instructions were to plug the highest current draw closest to the power cord and work your way back through your system to the least. Amp, Preamp, CD, Dac....... best $60 bucks ever.

They went out of sight for a gew years but AV Options.com carries newer higher performance versions along with Cryogenic properties. Additional power Cords can be purchased as well.

If interested, Google Stereophile.com and search Naim Wiremold.

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