Speaker Isolation -- Experience with Townshend Seismic Isolation Podiums


Over the past several months the new Townshend Seismic Isolation Podiums have been receiving some interesting and positive press. Living as I do in both an earthquake zone (Pacific NW) and in a busy urban setting with a lot of rumble from construction and passing vehicles I thought these could be worth exploring for my setup. As I was not able to find a US distributor I purchase direct from the UK (via Analogue Seduction, highly recommended). I placed an online order, with follow up to confirm the size and weight of my speakers and about six weeks later they turned up on my doorstep (the platforms are made to order with loading on the cells specific to the weight of your speakers)

The Isolation Podiums are basically four load cells attached to a robust platform onto which you stand your speakers. While not cheap ($2500 for the size I needed) they are very well designed and easy to use. For example I was concerned about being able to move my 275lb Magico Q3s up onto the platforms -- actually it was easy as the platform at 20mm is lower than the speaker spikes so it was simply a matter of unscrewing each spike and shuffling the speaker across. Once onto the platforms fine leveling was easily possible by adjusting each load cell. All in all the podium system is very well designed and works exactly as intended.

But how does it sound? With several days listening experience I cannot recommend this product too highly for anyone who wants to hear the best from their speakers. My room is custom designed with a concrete slab floor so a solid surface but of course subject to external vibration. Prior to the podiums I'd been enjoying deep and dynamic bass but had occasionally felt that the sound became congested in more dynamic and complex material. With the podiums all of this clears up. First impression may be of less bass but as is typically the case this was a result of a reduction in boom and smear and instead more of the open sound of real bass (think of a bass drum as being more "whoof" than "thump" after the initial leading edge - too often the sense of large volumes of air being displaced is lost. In addition I became much more aware of all the rhythmic leading edge detail in bass guitar passages, all the little cues the bassist is putting in. Furthermore it became much easier to resolve bass alongside other instruments. Example in point "Bye Bye Blackbird" by Nancy Harms (https://www.youtube.com/watch?v=yd4tQrndlFw). This opens with deep full bass which is a first test but then quickly becomes quite a crowded and in many systems overloaded mix. With the podium in place all of the instruments became much easier to separate and what had been a congested and even edgy mix became clear.

One final and unexpected change is how you can now more easily hear the recording venue. Listening at the start of recordings the sound of the room itself is a very low level mix of rumbles which (when it's present on the recording) is all too easy to lose -- the podiums help uncover this detail and create a much greater sense of real instruments in space. All in all I'd recommend you give these a try and no need to believe in voodoo to buy in to this tweak.
128x128folkfreak
Hello folks!

I'm going to experiment with the Seismic speaker podiums as well.  I was wondering if anyone has thought about the speaker weight distribution?

My speaker cabinets (Marten Coltrane Tenors) are full carbon fiber (so they are very light overall), but the front baffle is wood and all the drivers are mounted there.  This makes the speaker front heavy.  The speakers are 86.6 lbs each.  Do you guys think it might be fine to go with 2 green dot springs in the back (min weight 17 lb, max weight, 35 lb per spring) and 2 blue dot springs (min. weight 35lb, max weight, 75 lb).  Or shall I stay with all green dot springs?

Hello folks!

I’m going to experiment with the Seismic speaker podiums as well. I was wondering if anyone has thought about the speaker weight distribution?

My speaker cabinets (Marten Coltrane Tenors) are full carbon fiber (so they are very light overall), but the front baffle is wood and all the drivers are mounted there. This makes the speaker front heavy. The speakers are 86.6 lbs each. Do you guys think it might be fine to go with 2 green dot springs in the back (min weight 17 lb, max weight, 35 lb per spring) and 2 blue dot springs (min. weight 35lb, max weight, 75 lb). Or shall I stay with all green dot springs?

>>>>Ordinarily, all springs would have to be the *same spring rate* - otherwise the speakers would flop over. I have not seen Podiums but the way to deal with uneven weight distribution for anything on *independent* springs is manually move one or two springs slightly in the direction of max mass until the object on the springs is level. Same for leveling turntable or CD player. If the podiums are all one piece you can try moving the speakers along the podiums back to front until they’re level. If the poses are moveable then just move the poss in the back toward the front. I daresay most speakers have most of their mass in the front, so undoubtedly they thought of this issue.


@shaizada re your concerns on weight distribution I think the option recommended by Townshend is to locate the speaker slightly back in the platform that way the tendency to tilt forward is countered as Geoff suggested.

Please do however consult with the dealer who is supplying you as they are the ultimate arbiter. The podiums are usually custom built for your particular situation so they will know what is best to do