Home How well does speaker decoupling work? Townshend, Isoacoustics, Primacoustic

How well does speaker decoupling work? Townshend, Isoacoustics, Primacoustic


Price: € 480 - 2279



On Sunday, April 24, we tried out three speaker decoupling systems for you. The Townshend seismic isolation platforms, Isoacoustics Gaia II and the Primacoustic RX12. We combined these systems with a pair of ATC SCM40A to check out the results. And yes: the differences are greater than we thought!

It’s always interesting to delve into things you don’t deal with on a daily basis. Admittedly, we tested a couple of Townshends years back, and yes: we use some Gaia II under the Focal Sopras; very few other systems have we tested extensively. Speakers we also always just test with the spikes that come with it. In short: it is interesting to try three systems with one set of speakers.

Besides the ATC SCM40A we also have the Sonnet Pasithea, Metrum Acoustics Ambre streamer, Mutec MC3+ reclocker and as an extra an ATC C1 subwoofer. Cabling is from Yeti and Grimm. Energy filtering is done by Isotek.

Townshend Seismic platform

We start with the Townshend Seismic platforms. These cost about 2200 Euro per set of two (in the video we say per piece, but that is incorrect). The special thing about the Townshend is that they really make the speaker float. Through the spring / piston construction (specified by weight), the speaker can be completely disconnected. A very nice system. And it looks great too. We received two platforms for the ATC SCM40A and one for the subwoofer from Your Hifi Choice (Netherlands). The platforms for the SCM40A are versions with green stickers; they work up to 60 Kg. The sub has a mix of yellow and green.

We configured and tuned this system the Friday before the stream. (We always build up the stream on friday). We we glad we had some time, because, tuning them can be a tedious job, because the tension determines the performance. We first locked everything in place and then slowly but surely unscrewed it until it was floating freely.

The difference between the Townshend and spikes is really big. What we hear with the SCM40A is that the whole plays looser and that the imaging is larger. Both in width, depth and height. This is really something that is not (yet) heard in the stream; unfortunately. The sound balance also improves. The whole is calmer and easier to follow. However, your author (and colleagues) find the effect with the subwoofer not as great. That may be due to the ‘wrong’ distance of the down firing woofer to the floor. Perhaps with a front / side firing woofer it does work. The bass is just less tight and it also comes across as a bit ‘puffy’ and woolly.

Later in the stream we play with a combination of Primacoustic under the subwoofer and the Townshend under the SCM40A and that is really beautiful. The whole picture is just right. It will set you back a serious amount, but hey: the results are there!

Isoacoustics Gaia

We are quite satisfied with the Isoacoustics products. The Dutch importer let us try several flavors. Under the Sopra No1 they work very well. And also with the DALI Epicon 2 it goes very well. Geoffrey and Yung have been using the Aperta platforms under various products for a while now and they have no complaints either. The idea is that these feet decouple the speaker from the surface. This is done, as with Townshend, with certain rubbers adapted to the weight class. The Gaia II works from 32 Kg to 55 Kg. Exactly in the weight class of the SCM40A.

Now the ATC SCM40A is a closed system and we are guessing that this does not go so well with the GAIAs. In any case, it is the only reason we can think of why the midrange becomes a bit harsh and sharp. It’s as if the energy doesn’t get out properly anymore and is looking for a way out through the units. In a bass reflex system, the energy can always exit through the port; in a closed cabinet, it cannot. There it looks for another way to dissipate.

What is also noticeable, however, is that the stereo image grows. There is more air in the imaging. It’s not as big as the Townshend, but it’s noticeably bigger than the spikes. We estimate that these would do better than the Townshend under the subwoofer.

What we learn from this is that not everything can be predicted. And that a good product like the Isoacoustics doesn’t always work at its best. In this case it’s just an unfortunate match. That can happen. However, we strongly recommend to take these feet into consideration, because in many cases you have a very interesting product for a good price.


Finally, we received two more large Primacoustic RX12 platforms from Helios. These were initially intended for under the subwoofer, however, they turn out to work great under the SCM40A as well. However, we start with a swap under the ATC C1 subwoofer. When we switch from the Townshend to the normal feet we already hear some more kick and balance. From the regular feet to the Primacoustic is just bizarre. What a calmness and control. And without any wooliness. This works extremely well.

What is also noticeable, however, is that it works well under the ATC SCM40A. We hear more control and more energy. However, it can also get a bit dry and compact at times. That is very nice in a studio, because it listens easier and it may give a little more insight. But the stereo image can also become a bit compact for a ‘hi-fi experience’. Although your author must confess that he does like it. The calmness and control.

The sound balance with the Primacoustic is just very pleasant. When we are experimenting anyway at the end and we switch to a combination of Townshend under the ATCs and Primacoustic under the sub, everything is complete. This is ultimate… And not cheap. But hey: the results are great!

Winkels met Isoacoustics

Schoenmakersstraat 19
6041EX Roermond, NL
St. Ceciliastraat 28
5038 HA Tilburg, NL
Geldropseweg 105
5611 SE Eindhoven, NL
Breestraat 146-148
2311CX Leiden, Zuid Holland, NL
Steenstraat 54
6828 CM Arnhem, Gelderland, NL
Beethovenstraat 9-b
1077 HL Amsterdam, Noord Holland, NL