Speaker Isolation Advice Please

I have a pair of large floor-standing Klipsch Forte III speakers. For anyone not familiar with these they are permanently attached to wooden plinths that raise the cabinet a few cm off the floor. They sit on a carpeted suspended wooden floor.

I’m not unhappy with the performance but I can’t help wondering if things may be substantially improved by some form of isolation under them. Here lies the difficulties. They are extremely heavy (30Kg +) so lifting them to put anything underneath is, for me, dangerous. I’ve already had a hernia repair op a few years ago and frankly I don’t relish a repetition of that! I could perhaps tilt them to slide some form of isolation underneath. I was thinking along the lines of Vibrapods or something similar. Or even some sorbothane pads.

Any observations or suggestions very welcome. Thanks everybody.

I have now experience with this speakers. But there are already numerous threads on this topic here in the forum. Many members have had good experiences with Isoacoustics Gaia or with Townshend Isolation Bars. I myself use Isoacoustics Gaia, which are available for different weight classes of speakers. You can find more information under these keywords in the search function. Maybe neighbours can help you with the installation or your dealer can lend you demo models.

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Wilfried,

Thanks for your reply. I considered the Townsend bars but really they are just too expensive! I have used the Isoacoustics Gaia’s myself in the past with smaller speakers and had excellent results. Unfortunately they are not an option here as there are no threaded inserts on the speaker bases.

I feel I am running out of options and hoping someone can come up with something. I was considering also something like granite slabs. If anyone has any experience of the effects of these on a suspended wooden floor then that would be very interesting.

My PMC 20.25s are on granite slabs, but I don’t think the slabs themselves make much difference (I too have a suspended, uneven floor). I used the spikes between the slabs and the speakers to start with, then put Gaia IIIs, which did improve the sound.

These don’t require threaded inserts and go up to 14.5 KGs each. Three would be wiggle free too.

Thanks SamClaus and RvL.

The Isoacoustics pucks would be a definite possibility, except for two things. Sorry to be so awkward here, but to me these issues are of vital importance. Firstly getting them under the speakers is impossible without the help of two other people to lift them. Secondly, once the pucks are installed and run in then the speakers will almost certainly require re-postioning to get the correct bass alignment. This will involve experimentation and again will require two other people to help.

Put simply - I don’t have access to two other people to help me! I certainly do not trust neighbours to handle my precious expensive speakers. As well meaning as they are, they will likely regard them as ‘just speakers’ and really of no great importance - so it really won’t matter if they get messed up.

To be honest on balance I’m inclined to leave well alone.

To put anything at all under them you either have to accept having to list the speakers with a single slab-type support, or with three or four supports tilt to one side, put under, then tilt the other was and put the others under. It’s that or nothing if you don’t have assistance. And moving is a therefore fiddly process, but for most setups once done that’s it. Having 48kg speakers myself the tilt to one side first is what I do.

Isoacoustics recommend putting a dishcloth under the feet for positioning. At least with the threaded feet, this makes them reasonably easy to push around, but of course it may be different with pucks.

In final position, you would in any case have to lift the speakers corner-by-corner to pull out the cloth. The non-attached pucks are probably a bit of a hassle there, because you might pull them out together with the cloth and have to stick them back in.

Therefore, I would nevertheless recommend help. But at least you don’t have to lift the speakers entirely, and I suppose even a clumsy neighbor may be trusted with lifting a corner of a box, with proper instructions

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May I ask what you believe could be lacking at the moment?

Check out Herbie’s Audio Lab. Little Fat Gliders. Four per side will do the trick.

Also AV Room Service. Equipment Vibration Protection. Also four per side.

I have used them under three separate Proac floor standers with good success.

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For large speakers like those I would use either Herbie’s Giant Fat Dots or Giant Fat Gliders if you want to be able to slide them easily across bare or carpeted floors. In my almost 4 decades of tinkering with this hobbie this is the single most dramatic and transformational “upgrade” I’ve ever done.

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@liatpoh76

Agreed! Herbie’s products are effective and great value.

AV Room Service are a much thicker, more expensive and I don’t think they slide around.

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Similarly, another endorsement for Isoacoustics Gaia as they did improve on the spikes below the speaker stands in my system. I understand the Gaias and Oreas are not an option for you. It may be a wise choice to leave it as is if the system does not sound terribly off.

Just a note. Based on my limited experience, I suspect there are more ineffective isolation products in the market usually cheap, than the effective ones usually more expensive. Unfortunately, the effective isolators which bring noticeable or significant gains are usually expensive. The Townshend products are said to outperform most cheaper options which include the Isoacoustics equivalent. There are people who took measurements and simulation in REW. The measured distortion of some of the products (taken from another forum) as follows;

4.72% average with spikes.

4.64% average with Isoacoustics Orea.

4.28% average with Isoacoustics Gaia.

3.86% average with Nobsound 2-3mm space.

2.42% average with the Townshend Podiums.

2.11% with the Credo.

The message I am trying to convey here is to do it properly if seeking a worthwhile improvement. Otherwise, just stay put to avoid disappointment ie. not finding any audible difference with most of the cheap or ineffective isolators.

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Maybe this doesn’t help for peace of mind @Pete01 but…

I’ve browsed pictures of the Forte IIIs. From what I’ve found, it looks like the feet are shallow metal coin-like sliders on the corners? If they stand on these thin ‘coins’, on a carpeted suspended wooden floor, I would also think there is room for substantial improvement. As it is, they seem to be neither coupled (spikes) or decoupled via isolation. Typically not a recipe for best performance imo.

The underside of the speakers doesn’t look very suitable for puck-type isolators like Gaias. If it was me, I would save up for Townsend bars. Installing them under the speakers is only a one time exercise. I imagine the supplying dealer is willing to help here too. It’s like a 10-15 minute job.

If (…) repositioning is needed, you can put something like 4 pieces from a plastic bag under the feet to slide them around over the carpet and remove when done. This shouldn’t be too difficult.

Nothing specific. I suppose it’s just that I know the speakers are not well isolated from the floor and therefore I have the feeling that isolating them should bring about improvements. Of course things don’t always follow and I could be wrong.

Many thanks to all for your suggestions and comments.

Bang on here. Yes the Townsend bars would be ideal I feel, and perhaps not too difficult to install as they are very low. But ouch! that price!

Yes I agree. Probably I’ll leave it for the moment as I really don’t want to spend another £1000+ on the hi-fi.

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What about placing the speaker on a granite slab which in turn was on some isoacoustic pucks? Or just some washing machine feet.

James, yes I considered this but again it’s the problem of getting them up onto the slabs without causing damage to either them or myself.

They actually are attached to wooden plinths (see a picture online if you can be bothered) and I’m starting to be inclined to the view that these are built-in stands of sorts and so an integral part of the design/performance. No doubt these provide a degree of floor decoupling and perhaps adding anything extra may actually detract from this. I notice that in nearly all on-line pictures they are not resting on anything extra.

Finite elemente cerabases have inserts for the speakers bases. The replace the cones.
I use them under my speakers, on suspended wood floor, with great results.

The Stereophile review has reference to decoupling the Forte III, specifically not to couple them to the floor, BXI pads mentioned which can be found on Amazon at £17.99 for two (not quite sure what use two are, but perhaps that gives you a choice of three or four under a pair of speakers).
Accepting there is still a problem in getting them under the speakers, this is a cheaper option. Even cheaper if you want to experiment, go to a pound shop and buy cork sanding blocks?