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The Mortite Damping Tweak

This is the one that started me on modding and tweaking. An acquaintance showed me this one and I could not believe the difference. Mortite is a non hardening putty that can be found in any major hardware store. Mainly used as a window sealant. Sold in rolls.

 

DYNAMIC (CONE) SPEAKER

I have performed this mod on many speakers and have yet to find one in which performance was not enhanced.Start by removing the midrange or bass driver from the cabinet. You won’t have to disconnect the wires to the driver. It will help if you have a bunch of strips of Mortite already laid out. As a test of the driver, hold it by the magnet and tap the mounting flange with a fingernail. You will quite probably hear some sort of ringing. Especially if the basket is made of stamped metal instead of molded plastic.Now start applying Mortite to the back of the basket, making sure not to obstruct any portion of the cone. Repeat the finger rap test. Hear the difference? Reassemble and put on a pop record with, say, a lot of tom tom runs. You should hear a marked increase in transient resolution. What you have just done is damp the ringing of the basket that obscures the decay of any transient. Theoretically, you may run across a speaker that does not like this treatment. In essence you have damped the basket resonance and moved it to a slightly higher frequency. The beauty of this tweak is it is easily removable. And for about two dollars per cone, it is well worth a try!

 

DIPOLES

I recently had a chance to work on a pair of older Infinity Betas. Just apply the Mortite all over the back of the panel.NOT ON THE DRIVERS! The owner and I were stunned at the improvement.We also made a modest improvement in the Betas by making "gaskets" for the drivers out of 1/16" Sorbathane sheets. Mounting them between driver and baffle

 

STRESS RELIEVER DAMPERS

You know those sand filled "stress reliever" squeezey things sold at department store counters? Try four of them under your components. Cheap and effective.

 

CAPACITOR UPGRADE

For those of you who know which end of a soldering iron to hold, and have some decent but mid-fi equipment, try this-Look in your component and make a list of all the caps inside, (i.e.-10uf / 100 volt). Order your favorite brand of high performance cap. If you want to hold the price down, call 1-800-digikey for their catalog. They stock the highly regarded Panasonic series of electrolytic caps. For 70-100 bucks you just might hold on to it for a few more years. Just replace, value for value, all the caps making sure to bypass with .01 to .1 polypropylene or polystyrene caps for cleaner high frequencies.

SPEAKER CABINET DAMPERS

Here is a nutty one. Forget the expensive discs you have seen advertised. Here is what I did to a pair of Audio Concepts Sapphire IIti’s. Find a local machine shop or scrap metal house. Ask if you can buy their used CARBIDE MILLING INSERTS. These will range in size from ½" square to 1" square by about ¼" thick. Carbide is a very hard, dense, and heavy metal. Apply them with double-sided tape on the rear or inside of the cabinet. It worked for me! While you are at it, ask if you could look through some scrap to find some ¼" to 3/8" thick plate that is about the size of your component. Paint with Fleckstone paint, ( a faux granite spray paint), put a few felt pads on the bottom, and bingo! Instant chassis weights

 

SPEAKER STANDS

This one is simple. Just go price some high quality stands and you will love this project. I made mine using 5/8" MDF. (Medium density fiberboard).Determine the height you will need, then just plan on making the stand as wide and deep as the speaker. Use wood screws to keep it tight. Line with doubled up plastic garbage bags and fill with sand. The ones pictured took 75lbs of sand each. Paint with Fleckstone paint in your choice of color and you are done! Shown are some before and after shots

Diffusers

This took a little while but it is well worth it. I wanted to experiment with diffusion but could not afford the real RPG product. Not wanting to go crazy detailing these things, I'm not much of a woodworker, I tried using readily available wood sizesUsing stock 2x4's and 1x6 wood, I made a plan for each unit to be a full period. (See THE MASTER HANDBOOK OF ACOUSTICS for details. You DO have a copy don't you?)Once assembled I again, painted them with Fleckstone. (See photos)These photos were taken in an older room I once had. DIG that CARPET!

Wall Mount Absorbers

Also shown are an early set of side wall absorbers. Using just stock 2/4's and 1/4" backing. The 2/4's make the frame. Staple fiberglass insulation inside and cover with your choice of fabric. Great for experimenting!

Outboard Crossover Box Audio Concepts Sapphire IIti

If you know this speaker, you know that it just cries out for this treatment! The Sapphire has its crossover components mounted on a removable board that comprises part of the rear of the enclosure. I was always hoping to find some sort of prefab box to use. This 6"x9" auto speaker enclosure from Radio Shack worked beautifully. I just ordered a replacement back for the Sapphires without the crossover attached, squared out the oval opening of the auto enclosure and hooked it all up. As the Focal driver used for the mid in the Sapphire is a dual voice coil design, All I had to do was add another set of binding posts to the rear and now it is tri-wired from the OB x-over to the speaker. It was a nice little project