[jrocks29ms@gmail.com]

Hey ya'll,
I have a sealed SVS sb-2000 PRO subwoofer, that for the most part I really like.
I've done some upgrades with GR research's speaker kits and come to find that dampening the speakers' drivers yielded some excellent results in the case of a stamped steel Midbass driver found in the Klipsch rp-600m speaker. (Mostly in the vocals and upper bass)
****In the case of my sub, one of the few flaws it has, is its build density. Unlike the SVS sb-3000 or larger, the svs sub lacks internal bracing, and the driver is some sort of a vented steel basket. I've taken the liberty of applying dyno-mat to the bottom panel of the subwoofer (which isn't visible) and this has helped reduced cabinet resonances and boom. In addition to laying a heavy book on top, and using the isolation feet, on my hardwood floor.

My question is, in the case of a sub, where the frequency is for the most part under 100 Hz; would there be any sonic benefit from using dynomat, or non-hardening clay, to dampen the basket of the sub frame, to knock out any audible ringing. I hesitate to mess with uninstalling drivers, lest I degrade the MDF cabinet, and reduce the seal quality.
Curious on how big a factor subwoofer frame ringing is on a sealed subwoofer; if those frequencies excite a steel basket like a full range driver does.

[nlitworld]

Having 2 SB2000 in the house makes me very curious to this idea. Definitely going to keep tabs on this thread and try out the sound deadening pad to the bottom of the cabinets. Thanks for the idea.

[jtcf]

That's one thing that I haven't tried yet. I'm curious also.After replacing 4 small SVS subs with 2 much larger HSU subs I've been struggling with some resonance/ringing that didn't occur with the smaller cabinets. Different footers actually make it worse. Dynomat is worth a try.

[tubav]

An old full range driver trick is to put rope caulk on the outside of the legs of the driver basket and wrap around the frame between the legs and the magnet. I've even put stick on craft felt on the inside of the legs. Be sure you don't interfere with the driver surround or spider. Rope caulk is available at Home Depot.

[jrocks29ms@gmail.com]

If the picture accurately describes the insides of the svs sb-2000/ Pro, there is no sound deadening (white) material on the bottom panel of the sub, that is why it yields such great results. If I can further increase sub bass detail, by dampening the driver, I'm going to give it a try. Modeling clay sticks well to a mid-bass driver. I have concerns about how well it will hold up in a high bass environment like a sub. so maybe then dynomat.
I just would be ticked if i removed the sub and installed this to find no difference other than my subs screws won't stay tightly in place.

[jrocks29ms@gmail.com]

ps IF you use dynomat, use a roller of some sort to put serious pressure over the entire applied area. Cover as much of the bottom panel as possible, it makes a noticeable improvement.

[jrocks29ms@gmail.com]

That's one thing that I haven't tried yet. I'm curious also.After replacing 4 small SVS subs with 2 much larger HSU subs I've been struggling with some resonance/ringing that didn't occur with the smaller cabinets. Different footers actually make it worse. Dynomat is worth a try.

If the walls of your sub cabinet aren't already treated, id recommend GR research's "no-Rez". I had intended to use it initially on my SVS sb-2000 pro until i realized they came factory treated on 3 sides, and that dynomat would be a good external solution since it only needed treatment on the bottom (4th side.)
I wonder if large panels of dynomat internally installed would increase bass tone reflections, and smear detail.
I would only put small strips of dynomat on the basket frame of the sub myself.

[jrocks29ms@gmail.com]

Man if you compare this to the svs sb 4000 pro this sub lols like some kind of cheap Chinese sub you would find in a pair of tower speakers. I give them credit, for the price point they did a good job, they ticked a lot of boxes. But I’m still curious if anyone knows If a stamped/vented aluminum or steel frame subwoofer will ring, and I’d this is in the audible range in a sealed subwoofer design.
For what it’s worth my high pass filter is 80 HZ with an 18 db roll off.
Has anyone dampened there subs frame with dynomat or clay or whatever else for this reason with positive effect?
4000 vs 2000
https://cdn.shopify.com/s/files/1/0921/3560/files/4000-driver.jpg?14886109406028879437
https://cdn.shopify.com/s/files/1/0921/3560/products/2000-pro-additional-2_eb65ff35-3bb7-40d5-a367-17abadd8333c_300x@2x.png?v=1612462873

[jtcf]

I was mulling over Dynomat,Sub dudes (homemade), etc. last night so decided to try the footers that were under the Quicksilver mono blocks I owned once which were positioned on the floor between the speakers. They are two inch slices of gray foam pipe insulation (1 1/4 pipe) one on each corner.I really wasn't expecting much,but to my surprise the bass tightened up considerably. The glare and overhang disappeared.
 I've tried IsoAcoustics feet and 4 inch thick cement bricks which didn't work at all and actually made the sound worse.These foam feet lift the subs up about 1/2 inch higher than the supplied feet.I have one of the two ports open.I have no idea if SVS subs would benefit from this simple tweak,having never tried it when I owned mine, but just wanted to pass it along.I was playing the same tracks as the evening before at the same volume and was expecting either no change or worse sound, so thank you for this thread and the motivation to try

[mlundy57]

For a rock solid cabinet, you can always build another cabinet with internal bracing like for Danny's single sealed servo sub. A link to the plans can be found here: https://gr-research.com/product/sub-series-servo-sealed/

You may have to recalculate the dimensions to fit your driver, amp, and to maintain the same internal volume as your current cabinet to account for the bracing. To further dampen the box add No-Rez to the sides AcoustaStuff or similar inside the cabinet.

[nlitworld]

I just stuck a sound deadening pad on the bottom of my SB2000s. We'll see if there's any notable difference. I did pop the back plate off and see inside. There's a polyfill mat on all 4 sides but I didn't see much of anything else. I could imagine some no-rez and angled corner bracing in the middle would improve things a bit there. All in all not bad for $500, but I'm sure nowhere near a GR sealed servo sub. Sounds like I'll have a no-rez order here shortly. 

[rotarius]

I am curious why the OP thinks it is the driver basket that is ringing?  I would think the resonance frequency of the metal is much higher than the frequencies the sub handles.  I purchased the sv2000 and returned it in a week.  Didn't think it was a great value at 500 bucks.  The cabinet is very light and unfortunately it was calling attention to itself a lot.  It just sounded off for music, can't comment on HT use.  The PB2000 is a different beast and worth the extra 100.

[kyrio_s]

I hesitate to mess with uninstalling drivers, lest I degrade the MDF cabinet, and reduce the seal quality.
Curious on how big a factor subwoofer frame ringing is on a sealed subwoofer; if those frequencies excite a steel basket like a full range driver does.

This particular sub comes apart easily by taking screws out the back (amp board), and front (driver).  There are no other seals to be messed with.  I lined the insides with No Rez, and there was much improvement.  I can't comment on driver's basket ringing, but your question gave me the idea to apply some more No-Rez to the solid parts of the driver's basket and leave the holes open for circulation, along with re-wiring the driver to the amp with better wire (it has a snap-on connector on the amp side and I didn't want to mess with it before).  Will post if these changes show any noticeable difference.

Next day update: I added No-Rez on the driver basket, and re-wired the amp > driver connection with 12 gauge (DH Labs OFH-12) wiring instead of stock 15s.  SVS ran four wires in parallel (two each for positive and negative) that attach to a plastic snap-on connector on the amp side.  For simplicity, I cut the original wires with a small space to strip the 15 gauge stubs and solder the new wiring.  In any case, there was a small but noticeable improvement in clarity as well as oomph/output at high volumes. 

[nlitworld]

Thanks for the update! I ordered up 2 sheets of no-rez and some wire from Hobbs yesterday so we'll see how that goes. I plan to run 2 strands of the solid copper hookup wire for each + and - but of course it had to be a stupid plastic connector to keep us from modifying it properly. Also I'm sure adding a sheet of no-rez to each sub will greatly help over the peach fuzz polyfill material. In all it should only help compared to stock and it's not really an expensive tweak.

[kyrio_s]

Glad to help, good luck with your upgrade! 

[nlitworld]

This weekend I did some messing in the garage and thought I'd post my findings. So I rewired the sub with the solid copper wire from GR Research and put in no-rez . Now I see why Kyrio mentioned the stupid plastic plugs and small gauge wire in the amp side. How cheezy. Not surprised as most people look at watts and low end numbers, not what type of wire for a $500 sub. Even still, they gotta make money somewhere. So I did as Kyrio had done of soldering the new wire to the woofer tabs and as close to the plugs but utilizing the old plastic connectors still. I'm debating on going back and soldering directly to the amp but that's down the road.

So after I got done upgrading those parts, I plugged them back in and started listening. Right away there was a little more impact but a hell of a lot more detail and texture to the bass. I quite enjoyed that fact as that was the ultimate goal.

Next bit of upgrades I had planned was to make some diy power cables for them. Nothing super fancy, just a good upgrade from the stock crap they send. So I got some Sonar Quest silver plugs, some tinned copper shielding and a length of 10/3 from Hobo Depot. Once I plugged them in, everything seemed a little fuzzy again, but new cable can do that. About 30 minutes later, somehow the volume turned up on the subs probably 5db out of nowhere. After turning the subs down 2 clicks (was only 7 clicks on, now it's 5) and continuing to listen this evening, they are overall a big improvement over stock form. Total cost was about $150 each so I'd say that was a decent value improvement and a fun upgrade project over the weekend. I'm excited to see how it sounds after a week or two.

[jrocks29ms@gmail.com]

I'm glad my curiosities yielded some positive results for folks. I did find a good power cord, and a good subwoofer cable, to be the most impactful. Secondly the dyno mat really helped that boom that detracted from the detail and bass nuances that are audible in music. I would say that there may be more to be had from the use of No rez.
At the moment the lack of oomph and more detail is likely due to power cable, it could be better, it makes an amazing difference yall. Also the internal wiring is quite cheap I hear and would likely be one of the biggest improvements, as its likely the weakest link in the connections.
What's the consensus for bass? Would the solid strand copper wiring GR research provides in its kits, (16-18 gauge) work well for subwoofer internal wiring?

[nlitworld]

Would the solid strand copper wiring GR research provides in its kits, (16-18 gauge) work well for subwoofer internal wiring?

My upgrade seemed to make a small improvement over stock, but I'm still left contemplating what it would be if I went a larger stranded cable directly soldered between driver and amp. Having the little pigtails of stock wire using the cheesy plugs always leaves me wondering.

[corndog71]

Warning!  You are drifting into Audiophilia Nervosa territory!  I would know.  I once rewired the speaker of my clock radio.  And yes, it sounded better. 

[NoahH]

Warning!  You are drifting into Audiophilia Nervosa territory!  I would know.  I once rewired the speaker of my clock radio.  And yes, it sounded better. 

It really improved the time domain.