[melchionda]

I'm a member of another forum centered on a specific speaker brand.  In this case the forum is specifically about the vintage speakers from this particular brand.  I'll keep it anonymous so as to prevent an inter forum battle.   Anyway... I own a pair of these vintage speakers and after upgrading my Warfedales with a GR Research kit I thought I would upgrade my vintage speakers too.  So I began the process of upgrading the speakers based on the agreed upon best practices of that community.  This included, removing the vinyl veneer on the cabinet and applying real wood veneer, adding internal bracing, damping the interior and exterior of driver baskets with dynamat, hurricane nuts for the drivers, applying extra glue to the magnets as well as buying all new higher quality crossover components and rebuilding the crossover.  The final step was to add a 4" square of foam to the interior back of the cabinet behind the base driver.  Wait... what???  only a 4" square?  The consensus among that community was that if you lined the entire interior with something like no-rez then the speakers sounded "muffled".  So I guess this particular speaker manufacturer was relying on the cabinet of the speaker to resonate to fill out the sound?  In discussing this one another member of this forum we thing that maybe lining the entire interior with no-rez will probably make the speaker sound less full but will probably have more detail.  Interested in your thoughts.

[mlundy57]

I always line the entire inside of my cabinets with No-Rez. I do peel the foam layer back 2" from the drivers and completely off the bottom leaving the damping layer on the panels. Lhis leaves room for the drivers to breath and a place for the cross over board on the bottom. If a particular cabinet doesn't have the crossover board mounted on the bottom, I leave the foam there and remove it from where the crossover board(s) are placed. I then add about 1oz of Acoustastuff (polyfill or insulation) behind the woofer and some over the crossover. If the cabinet has a port, make sure the Acoustastuff or whatever does not block the port.

This makes for a very well damped box that does not sound muffled.

While the entire inside of the box doesn't need to be covered for the No-Rez to be effective, I like the results when it is fully covered.

[corndog71]

I had a vintage pair of small floorstanding speakers from a company like that.  I took the crossover off of the binding post cup and mounted it to the bottom with all new caps.  I lined the cabinets with No Rez.  I also used better quality wire.  I took out the folded sheets of foam and added some poly fill.  There was definitely more clarity.  But most of the issues I had with the speaker couldn’t be fixed by any tweak.  It was just the design didn’t seem to work for me.

I just had to look up the specs and now I can kinda see what my problem was.



I didn’t have 3 meters at the apartment I was living in at the time.   

[FullRangeMan]

The final step was to add a 4" square of foam to the interior back of the cabinet behind the base driver.  Wait... what???  only a 4" square?  The consensus among that community was that if you lined the entire interior with something like no-rez then the speakers sounded "muffled".  So I guess this particular speaker manufacturer was relying on the cabinet of the speaker to resonate to fill out the sound?  In discussing this one another member of this forum we thing that maybe lining the entire interior with no-rez will probably make the speaker sound less full but will probably have more detail.  Interested in your thoughts.
I my experience with car audio, pro-audio and hi-fi boxed speaker are that everything (stuffing) you place inside the speaker box will have an effect in the sound, there is no general rules to follow as it all depend on the personal taste, so test and error are important.

In pro-audio speakers are common to use dry box for less cost and greater SPL.
But there is one item that I consider important for all hi-fi boxed speakers, that is paint the entire inside of the box matte black, so you would start from this point IMO.

[Zuman]

These are CSS Criton 2TD-X Towers. They're made from solid 3/4" quartersawn mahogany, lined with 1/4" ply, with 18mm Baltic birch ply braces and inner front baffle.
I kept all the NoRez pieces in place that you see in the photos, except for the bottom piece, which I ended up removing. There are twin 2" x 7.5" port tubes through the rear panel about three inches from the bottom. I started the No Rez 2" behind the woofers and ran it, as you can see, back to the rear panel.
I also placed NoRez on the rear panel between the braces, except for the bottom "compartment," and added loose Acousta-Stuf throughout.
The speakers sound really tight, and rapping a side panel sounds like you're hitting a cinderblock.

[melchionda]

The final step was to add a 4" square of foam to the interior back of the cabinet behind the base driver.  Wait... what???  only a 4" square?  The consensus among that community was that if you lined the entire interior with something like no-rez then the speakers sounded "muffled".  So I guess this particular speaker manufacturer was relying on the cabinet of the speaker to resonate to fill out the sound?  In discussing this one another member of this forum we thing that maybe lining the entire interior with no-rez will probably make the speaker sound less full but will probably have more detail.  Interested in your thoughts.
I my experience with car audio, pro-audio and hi-fi boxed speaker are that everything (stuffing) you place inside the speaker box will have an effect in the sound, there is no general rules to follow as it all depend on the personal taste, so test and error are important.

In pro-audio speakers are common to use dry box for less cost and greater SPL.
But there is one item that I consider important for all hi-fi boxed speakers, that is paint the entire inside of the box matte black, so you would start from this point IMO.

Interesting, what is the point of painting the inside of the speaker matte black?  Does it impact performance?

[FullRangeMan]

Interesting, what is the point of painting the inside of the speaker matte black?  Does it impact performance?

Its used by subs car audio guys to decrease mid/treble freqs. at low cost and yet dampen some carcinogenic formaldehyde vapors that MDF emanates for 5 years.

[Danny Richie]

The final step was to add a 4" square of foam to the interior back of the cabinet behind the base driver.  Wait... what???  only a 4" square?  The consensus among that community was that if you lined the entire interior with something like no-rez then the speakers sounded "muffled".  So I guess this particular speaker manufacturer was relying on the cabinet of the speaker to resonate to fill out the sound?  In discussing this one another member of this forum we thing that maybe lining the entire interior with no-rez will probably make the speaker sound less full but will probably have more detail.  Interested in your thoughts.

Keep in mind that box resonances are coloration and not part of the music signal. Technically it is just noise.

That noise can mask levels of detail.

Box resonances can sometimes be out of phase from the woofers output and reduce bass levels. Sometimes it is in phase and adds a bloaty buzz.

No Rez is great for removing that coloration and allowing you to hear the music.

[corndog71]

This reminds me of a guy I knew 20 years ago.  I tried explaining what hifi was all about but he didn’t want any part of it.  He preferred putting a speaker in every corner, dropping the highs and boosting the bass as much as possible. 😳