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Room Correction Bass Traps I would like to share some knowledge with others that are interested in making there own cylindrical bass traps. In my room I had a real problem with low frequencies muddying up the sound. No matter how I arraigned my setup I could not get rid of low frequency colorations in the sound. So what I did was purchased one of those Radio Shack decibel meters and walked around the room with sound playing and measured output at various parts of the room. And, as I expected, I was getting about 10 to 15 db more output coming from the corners of the room behind the speakers. I needed to do something to reduce this as I could not really enjoy my expensive system to the fullest. I checked out professional makers of bass traps but they wanted way to much money so I decided to make my own. I made two bass traps at 14” diameter (do absorb down to 50Hz), but you can make these any diameter you want for any frequency. They worked wonders on my sound and totally eliminated the colorations I was experiencing. Below are the instructions and places you can buy the materials. Enjoy! Instructions for cylindrical bass absorber Tools needed- • Caulking gun (for adhesive) • Staple gun • Pins (sewing) • Scissors • Razor knife • Not very much talent! You will locate the tube material at any industrial heating and cooling outlet. There are three or four brands, but the tube is used as the insulation cover of heating and cooling pipes. The brand I found in my area is Knauf fiberglass pipe covering. They come in assorted sizes, just remember that the specified size is the INSIDE dia. of the tube. IE- A 10 in. tube wraps around a 10 in. pipe. With the 1" thickness of the tube, the outside diameter would be 12". The tube is compressed fiberglass, and is 1 in. thick. They come stock in 3 ft. lengths. A rough rule of thumb is 10-in. tube will absorb down to about 70 Hz. 20 in. tube to around 40 Hz. The tube comes wrapped in an aluminum/paper backed wrap. This layer will become the reflective wrap of the absorber. DO NOT REMOVE YET! From a small sheet of 3/8-in. drywall, cut circles the same size as the outside diameter of the tube. These are the top and bottoms. You can use wood, but drywall is easier to work with. All you need is a surface to glue on and that will hold staples. The tube is split on one side so as to put around pipes. Prop the tube open and run a nice thick bead of adhesive (Liquid Nails etc.) along the vertical edge. The paper covering has a peel back adhesive paper lip that holds the tube closed while it dries. Run a bead around the top. These beads MUST be gap free. The tube MUST be air tight for it to be effective. Place the drywall circle on the top with a slight turning motion to ensure the adhesive is gap free. Repeat on the bottom. Place a couple of books on it overnight to cure. Above and right I have dismantled one for show.You can see the glued on drywall with half of the tube covered in the supplied paper. The side with the paper showing is the front, for diffusion. The side showing the raw tube is the absorbent side. Here also you can see the rear of the fabric just folded over and pinned. As it faces the corner, it will never be seen. I needed to match the fabric to the traps that I already owned, so I tracked down Guilford. They can be reached at- Guilford of Maine Textile Resources 5300 Corporate Grove Dr. SE Suite 200 Grand Rapids, MI 49512-5512 1 800 544 0200 The Crème color ASC uses is called Quartz, FR 701, Style 2100, #380. You can order it custom cut for a couple bucks more. Don't get caught up in finding a fabric that you think has to "breath" like open weave burlap. (Ugly!) Bass does not travel in waves, it behaves as pressure. (If bass can go right through a flimsy wall, it will certainly go through a piece of fabric!) When the trap is dry, cut half of the diameter paper off. I cut off the side away from the seam. Now one side is reflective, the other, absorptive. Cut the fabric so it overlaps the ends of the tube about three inches each end. Wrap the fabric around the trap and pin down the seam. Don't worry about getting it super tight now, you will get it tight when you staple the top and bottom. Fold the fabric over top and put a couple of staples to hold it. Directly in line from that, pull the bottom tight and staple. Work your way around, alternating top and bottom. Make sure you decide which way you want facing outward before you wrap it. IE- the side that faces the wall will have the seam, unless you care to sew the seam. (Good luck!) Below are two shots of the finished absorbers. Once stacked, you don't notice the ends. If one is a little handier than I, you could make some fancy wooden end caps to finish them off. Or I have also thought of using the thin counter top veneer end pieces that could wrap around as a "seam", and then fastening them at the rear. I have also looked for sized matched plastic flower pots! But no luck yet. I stopped at this point. If anyone takes this a step further, please drop me a note with the details. Have fun! Here is the latest price list I have. This is from- American Mechanical Insulation Sales Inc. 38900 W. Ten Mile Road Farmington Hills MI, 48335 Phone-(248) 478-7644

I must have been tired when I posted, because I forgot to include my sub. Since i see others have the B&W/Krell combo, it would be interesting to see who uses what sub. Currently, I use the Martin Logan Depth sub. I have done a lot of auditioning for subs and my dealer turned me on to the Martin Logan line. You can actually balance a quarter on edge with this sub at full output and it will not fall down. They use 3, 8” drivers at 120 degrees apart to cancel out resonance and vibration. There subs are very quick and have no issues keeping up with the B&W’s.

I will look into those, plus from Chris's CASH list I see there are internal fans that produce low noise as well. Also, in trying to minimize noise further with rotating motors what would you think of removing the hard drive and placing in one of those external cages and placing far from computer/equipment? It is a SATA type connected hard drive and I could run extension wires to computer and install one of those RF ferrets to help prevent noise coming back into computer.

Hi to all fellow Audiophiles out there. I have to admit this site is AWESOME!!! I was planning to do a computer music system and could not find much info on the web until I found this site on a Google search. My hat off to you Chris. Anyway, I wanted to share my system with everyone here to not only help individuals going down the same path as I, but to also get some recommendations/changes from other members. Below is where I am at and going: • HP Desktop - I am going the way of Windows and PC, so my choice was an HP desktop (Quad core Intel, 4 gig RAM, The quietest power supply I could find, Vista 64). o Went through the BIOS and operating system thoroughly from my own experiences and from the experiences of others on this site to streamline apps/services, and drivers. o I use JRiver Media Center and WASAPI • M-Audio 192 PCI sound card – My strategy was to use S/PDIF digital out transmissions rather than USB. I just don’t think USB is where it needs to be and did not feel like spending the big bucks on a premium USB DAC. Plus, after much research the S/PDIF connector on the M-Audio is transformer coupled. • PS Audio Digital Link iii DAC – For the money I feel this DAC is the best for S/PDIF and Toslink. I choose this DAC for the separate toroidal transformer, latest D/A chips, and no OP-Amps output stages. This in turn produces a warm, huge soundstage sound I was after. o Audioquest Hawkeye S/PDIF cable - I connected this DAC to the M-Audio using Audioquest’s Hawkeye digital cable that uses pure sterling silver as the electrode and DBS biasing to reduce any skin-effect that could affect the sound. • Krell 400xi Integrated Amp – It was either this Krell or Rotel RB-1090/RC-1090. I am really big fan of Rotel gear, but could not get the smooth clear upper range that the Krell produced. For the money the 400xi on the Audiogon is a steal. o Analysis Plus Solo Crystal interconnects – I LOVE these wires. My local HiFi shop turned me on to this company and I have not looked back. These interconnects are XLR type and I connect the Krell to the PS Audio using the fully balanced connections. The Krell really comes to life using full balanced connections to un-balanced (RCA). • B&W 805s speakers – I am a big fan of B&W and have owned speakers in almost every category they have. I cannot find a better speaker that images the way these speakers do. o Analysis Plus Copper Oval 9 and Oval 12 – I shotgun these wires, the Oval 9 for midrange and Oval 12 for highs. o Sanus UF-30 speaker stands – For the money these stands are awesome. Not just a simple stand, but a lot of detail to produce the best sound for bookshelf speakers. Much cheaper than B&W stands. • Panamax 5510 power conditioner/isolation transformer – I noticed a BIG difference of low noise floor and smoothness when I connect the digital sources apart from the analog sources using the isolation transformer. o PS Audio XStream Statement power cables – Cables sound awesome!!! and are built like a tank. My next steps on improvement are the following: o Krell - There is a great company located in Michigan called The Upgrade Company. They specialize in upgrading equipment to sound much better than original. They charge about $800 and totally upgrade all components to top notch stuff purposely left out to keep cost down (seems all companies do this) o PS Audio DAC – I am researching the Cullin’s mods and/or waiting for the new PS Audio digital lens Chris mentions they are coming out with to totally control the clock and reduce jitter even more. o DIY room tune – This one is the biggest, I have been working with others in my local area to make DIY bass traps. These cost a fraction of what the ones from Room Tune cost and do not take much time to make. Plus, you can vary the shapes to control what frequencies you want to absorb, etc. (more to come on this one). So this is my system and where I want to take this hobby of mine. I would like to get any suggestions to enhancements I could make or something I could be doing better. Thanks Steve