2 Things that speaker modifiers and DIY's will like.

JesusJones

Well-Known Member
I can't list how many times I have used "Duct Seal" when modifying speakers. Duct Seal is a very cheap type of ticky tack (almost). You can get a 1lb brick for 3$ at Home Depot. And I'm sure many other types exist.

It's non-toxic and never dries out. So it can always be removed if you don't like what you did with it.

Just recently I used it to dampen the basket of mid range driver. Much like it was done to this driver
http://diyaudioprojects.com/Drivers/40-1197/40-1197.htm

You dampen the basket and also fill the space between magnet and basket where resonances can occur. And this gets rid of what I like to call the "telephone effect". I've heard of many people using all sorts of strange things to dampen speakers and I always think. They could of done that much easier and more cheaply. Not that they did anything wrong at all. It's just not the product I would have gone out and bought.

Along with that you can make gaskets from it. Just put some around the edge of where the driver sits. You can use it to make boxes with small holes or cracks airtight again. And don't forget dampening woofer baskets. And as always if you don't like the effect removal is easy and quick.

Just thought I would inform the masses on that one.

And also I just acquired some stands that would be easy to build and I think would suit most peoples needs and preform very well. Actually it's "THE BEST SPEAKER STAND" :thmbsp:

From those pictures you should be able to figure out how to build one with some 3/4mdf. Just glue it all together. (It is hollow) Then the part that makes it The Best.

Buy some Stuff....for lack of better words. I have no idea what it's called but you would use it for coating the handles of hand tools. My teacher in High School had some. So you can for sure buy it somewhere. It would be like a very soft rubber when it dries with lots of traction. Coat the whole thing with that "stuff" that way the speaker will be firmly secured to the floor, angled upwards nicely and slightly raised.(and thanks to Clydeselsor we now know that one of those products is called "Color Guard" :yes:)

I hope that is of help to some people and that it will be put to good use.
Enjoy,
Rudy

TerryO says:

"I've used Duct Seal for a number of years and before that Oil-based modeling clay, which is probably better for damping the inside of cabinets, as recommended by Ed Heath on the old Bass List. If you're modding cheap drivers, you might try using an epoxy/pulverized Lime putty applied around the junction of the basket and magnet before using the duct seal. You can also use felt, glued with Aleene's Original Tacky Glue to the inside spokes of the basket to absorb some reflections back into the cone. Finally, use some really healthy felt to fashion a cap around the entire magnet structure covering the sides and back, also glued with Aleene's. Dave Duglos (Planet10) liked my mod enough to try it himself. There was an actual improvement in the impedence measurements taken before and afterwards. If you run your drivers fullrange with SETs, you should have some improvement in the bass." added march 25th 2010
 

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Ductseal is my good friend, I never like a pair of speakers until they are filled with it! A day and night difference nearly every time (based on about 10 attempts).
 
I've used Duct Seal for a number of years and before that Oil-based modeling clay, which is probably better for damping the inside of cabinets, as recommended by Ed Heath on the old Bass List. If you're modding cheap drivers, you might try using an epoxy/pulverized Lime putty applied around the junction of the basket and magnet before using the duct seal. You can also use felt, glued with Aleene's Original Tacky Glue to the inside spokes of the basket to absorb some reflections back into the cone. Finally, use some really healthy felt to fashion a cap around the entire magnet structure covering the sides and back, also glued with Aleene's. Dave Duglos (Planet10) liked my mod enough to try it himself. There was an actual improvement in the impedence measurements taken before and afterwards. If you run your drivers fullrange with SETs, you should have some improvement in the bass.

There are several things that can be done to the cones themselves, like the Enable treatment patented by my friend Bud Purvine. It seems to help some drivers more than others, so YMMV.

Best Regards,
TerryO
 
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Yep if ten speakers doesn't make you think there's some magic to Duct Seal I don't know what will :yes:

I've used Duct Seal for a number of years and before that Oil-based modeling clay, which is probably better for damping the inside of cabinets, as recommended by Ed Heath on the old Bass List. If you're modding cheap drivers, you might try using an epoxy/pulverized Lime putty applied around the junction of the basket and magnet before using the duct seal. You can also use felt, glued with Aleene's Original Tacky Glue to the inside spokes of the basket to absorb some reflections back into the cone. Finally, use some really healthy felt to fashion a cap around the entire magnet structure covering the sides and back, also glued with Aleene's. Dave Duglos (Planet10) liked my mod enough to try it himself. There was an actual improvement in the impedence measurements taken before and afterwards. If you run your drivers fullrange with SETs, you should have some improvement in the bass.

There are several things that can be done to the cones themselves, like the Enable treatment patented by my friend Bud Purvine. It seems to help some drivers more than others, so YMMV.

Beswt Regards,
TerryO

That felt on the inside of the basket is one I've never heard of. Definatley gonna give it a shot. But I'm gonna use duct seal to hold it in :D

I like the fact you can undo it if you don't like the effect. That's the main reason I love it. It can always come off in a couple minutes.

Mind if I throw that paragraph into the original post??(with credit going to you of coarse) Try to get as many mods and tips into one useful post.

Rudy
 
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Yep if ten speakers doesn't make you think there's some magic to Duct Seal I don't know what will :yes:



That felt on the inside of the basket is one I've never heard of. Definatley gonna give it a shot. But I'm gonna use duct seal to hold it in :D

I like the fact you can undo it if you don't like the effect. That's the main reason I love it. It can always come off in a couple minutes.

Mind if I throw that paragraph into the original post??(with credit going to you of coarse) Try to get as many mods and tips into one useful post.

Rudy

Rudy,
I'm sorry I missed your post, but sure, go ahead.

There are a lot of pretty good sounding inexpensive drivers that can, with a little work, become great sounding drivers. Usually the main differences between the high priced drivers and inexpensive drivers are in power handling, consistency of specs and things like a cast chassis. For most applications in home audio the power handling is probably not a big factor at the volume levels that normal listening requires. A cast chassis may or may not lend itself to improved sound, but the use of the epoxy/pulverized lime fillet along with the damping of duct seal makes the comparisons almost a non-issue. The consistency of specs is important to the manufacturing of a line of speakers, but not necessarily to the hobbiest who can work with what he has.

An example of this would be the close-out sale a few years back of what became known as the NSB (No Stinkin' Badges) 4 inch drivers from PE. I picked up a couple of dozen of these for $.49 apiece for a Cub Scout project. One of the Scout Dads measure them against some 4 inch Audax drivers that he's bought for $49.00 each...well, you can read it for yourself:

http://theloniousbonk.smugmug.com/gallery/505390/1

BTW: The measurements shown are without any mods, so you can draw your own conclusions. {Edit: There aren't any measurements evidently, but the NSBs were more linear}

Best Regards,
TerryO
 
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Would all speakers benefit from this? I mean, should i also put it on tweeters?

some tweeters won't benefit from this. they are already completely solid and theres no cracks or crevices (where resonances can occur) to fill. But some might :scratch2:


And heres a new one I just came up with today. I got the inspiration after reading "Engineering the AR-9 by Tim Holl" on the classic speaker pages.(specifically page 11)

This one is rather simple and requires no taking apart of speakers. The theory is also simple. When dome tweeters and midranges are used sound is dispersed in all directions. And any screws, small holes or knobs for tone controls and even the edges of the speakers on the front will cause reflections. Reflections that will make you hear sounds that are not directly from the tweeter/midrange. And are out of phase and all sorts of bad things.

So if you want to hear only the tweeter and midrange(and not a bunch of other mucked up reflected sounds) you need to put a material that does not reflect sound all over the front of the speaker completely surrounding the midrange/tweeter.

I used some strange old dampening material I pulled from an old speaker it's green and made up of all sorts of fibers. I also figure that Fur (from an animal) would not reflect sound and actually absorb it. You need to be creative here. I was just trying this as an experiment. And the results were not negative. And my speakers sound a little better. Can't say for sure though. But I won't be taking this mod off any time soon.

BUT some speakers were designed to be the way they are SO your mileage may vary

Rudy

P.S. I suggest you go here http://www.classicspeakerpages.net/...-9_by_tim/engineering_the_ar-9_by_tim_11.html
and read for yourself so you fully understand :thmbsp:
 
So I recently bought a microphone from Value village for 4$ and have been having some fun with it. It's a ec-5 superscope, made by marantz apparently The big box and the fact that there was a frequency response curve on the back kinda tipped me off that it might be worth buying. And so far it's been worth it just to play around with :thmbsp:

Then today at work I decided to measure my idea about putting a non-sound reflecting material over the front of a speaker. I also did one about doping a speaker but my computer crashed. The results from doping this small 4 incher were pretty stunning. Cleaned up the response very well, got rid of some serious dips around 8k and even boosted the high frequencies slightly. I wish I would have not lost that one. You could really see the difference.

Tomorrow I will also use that same 4 incher to show what kind of differences adding duct seal makes, along with some stickable tar stuff from work meant for roofing on the inside of baskets. (felt?)

But here are results for my idea (not really mine AR's idea) done on some dual speakers. The results are good in some areas and questionable in others. Wish the pictures were bigger but thats the best I could do for now.

RED is with foam/insulation on the front of the speakers

GREEN is just the speaker unmodified.

Enjoy!
 

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