More Feet/Spike Advice

MartinLogan Audio Owners Forum

Help Support MartinLogan Audio Owners Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Hi, I have ESLs and all my equipment is on homemade ball bearing pucks that I machined to some specs from a producer. It made a difference.
Has anyone tried them under their speakers?

thanks
 
I'm posting to this thread in hopes that someone with loads more experience might explain how both of these approaches could possibly be best. It sure seems like steel spikes (which would in theory prevent the plane of the electrostat from swaying) would produce the exact opposite effect of Isolation Feet (which would allow the plane to swing back and forth). How is it that both could be good solutions? I'm trying to understand the theory of how both work.....

I personally have ML Montis speakers. I have always used ML steel spikes on them but recently found that the spikes caused some annoying rattling noise at moderately high volume with low frequency, deep base music. I removed the spikes and the rattling went away. (My speakers are on carpet, on pad and then a concrete slab floor.)

I am considering trying IsoAcoustics GAIA III's, but would love to better understand the theory.


Hi Biker, as no-one else has responded to your questions, I will try ……

Products such as IsoAcoustics GAIAs and the Townshend Audio Seismic Isolation Podiums, work by isolating the speaker from the floor using resilient mounts.
These isolation devices are low pass filters which allow the speaker to move at very low frequencies, but at higher frequencies they are held rigidly.

What this does is to reduce the levels of vibration put into the floor by the speaker, helping to reduce potential feedback into source components, and also ensures that the speakers are significantly less effected by vibrations passing into the speaker from the floor, generated by passing road traffic or other sources. Townshend Audio have a video on the effects of ground borne vibration:

Isolation mounts such as the GAIAs allow the speaker to operate as it should do, with reduced clouding/feedback.
When you consider that isolation is a central design feature of the vast majority of record decks, to prevent external vibrations feeding back into the platter/arm/cartridge/signal, why should isolation be questionable for speakers?

You might like to check out an article by Keith Howard in HiFi News and Record Review, December 2017, “Isolation on the Cheap”. He explains these matters much better than I could, and also provides the underlying maths.

Yes, I purchased GAIAs to replace the ML supplied spikes, and the resulting improvement was not subtle. The floor is a carpeted concrete slab on top of thermal insulation.

As a further recommendation, Michael Fremer uses them under his Wilson Alexx speakers.
 
I installed IsoAcoustics footers soon after I purchased the ELS 15A’s. On a hardwood floor they produced a better sound presentation than the stock footers. A few months ago a friend let me try out the Stillpoints Ultra 6 isolation feet. There was a pronounced improvement in the bass frequencies and imaging. Since they were previously owned, I was able to afford them. However, I would start with the Stillpoints Aperture panels, as they had the biggest impact.

So, I understand the Stillpoints were more of an improvement than the IsoAccoustics feet, yes?
 
Hi Biker, as no-one else has responded to your questions, I will try ……

Products such as IsoAcoustics GAIAs and the Townshend Audio Seismic Isolation Podiums, work by isolating the speaker from the floor using resilient mounts.
These isolation devices are low pass filters which allow the speaker to move at very low frequencies, but at higher frequencies they are held rigidly.

What this does is to reduce the levels of vibration put into the floor by the speaker, helping to reduce potential feedback into source components, and also ensures that the speakers are significantly less effected by vibrations passing into the speaker from the floor, generated by passing road traffic or other sources. Townshend Audio have a video on the effects of ground borne vibration:

Isolation mounts such as the GAIAs allow the speaker to operate as it should do, with reduced clouding/feedback.
When you consider that isolation is a central design feature of the vast majority of record decks, to prevent external vibrations feeding back into the platter/arm/cartridge/signal, why should isolation be questionable for speakers?

You might like to check out an article by Keith Howard in HiFi News and Record Review, December 2017, “Isolation on the Cheap”. He explains these matters much better than I could, and also provides the underlying maths.

Yes, I purchased GAIAs to replace the ML supplied spikes, and the resulting improvement was not subtle. The floor is a carpeted concrete slab on top of thermal insulation.

As a further recommendation, Michael Fremer uses them under his Wilson Alexx speakers.

Wow, you heard a difference even though the floor under the speakers is concrete? I figured concrete wouldn't transmit vibrations very well.
 
Wow, you heard a difference even though the floor under the speakers is concrete? I figured concrete wouldn't transmit vibrations very well.


I don't know how thick the concrete is but, as I said, it was laid on top of thermal insulation material. I guess it would have been thick enough not to break up under normal domestic use but not so thick that it completely compressed the insulation.
 
So, I understand the Stillpoints were more of an improvement than the IsoAccoustics feet, yes?

For my part I went in the opposite direction from Stillpoints to GAIA 1's on my CLX Anniversaries.
 
I don't know how thick the concrete is but, as I said, it was laid on top of thermal insulation material. I guess it would have been thick enough not to break up under normal domestic use but not so thick that it completely compressed the insulation.
What is the thermal insulation material? Maybe it vibrates.
 
jda99 - Thank you for the detailed answer above. I have an engineering mind and I like to have at least some idea as to how something works (at least in theory). I have ordered the Iso Acoustics GAIA III Isolation feet and will give them a try and then report back with my findings. I have 30 days to try them out. If I hear no difference, I will send them back.

I have read good things and that the feet will help with my bass in my speakers, and it sounds like I may hear some secondary effects with reduction of vibration sent thru the floor to my tube pre amp as well.
 
Last edited:
jda99 - Thank you for the detailed answer above. I have an engineering mind and I like to have at least some idea as to how something works (at least in theory). I have ordered the Iso Acoustics GAIA III Isolation feet and will give them a try and then report back with my findings. I have 30 days to try them out. If I hear no difference, I will send them back.

I have read good things and that the feet will help with my bass in my speakers, and it sounds like I may hear some secondary effects with reduction of vibration sent thru the floor to my tube pre amp as well.
Don't use Gaia IIIs if you should be using Gaia IIs. Their recommended maximum load should not be exceeded as performance drops off quite quickly if overloaded.

The 11A, 13A, 15A range that have amps built into their bases require a special long thread for Gaias, but IsoAcoustic now know about this and can supply "Long 3/8-16 threads" for these ML speakers. The reason is that the spike fixing holes are designed with hex shape for the first 1/2" or so to allow removal of the amp tray, so the spiral thread is set well into the hole. I hope that makes sense! Peter
 
Don't use Gaia IIIs if you should be using Gaia IIs. Their recommended maximum load should not be exceeded as performance drops off quite quickly if overloaded.

The 11A, 13A, 15A range that have amps built into their bases require a special long thread for Gaias, but IsoAcoustic now know about this and can supply "Long 3/8-16 threads" for these ML speakers. The reason is that the spike fixing holes are designed with hex shape for the first 1/2" or so to allow removal of the amp tray, so the spiral thread is set well into the hole. I hope that makes sense! Peter

I spoke with Iso Acoustics and they recommend the GAIA III for the ML Montis speaker. They informed me of the special thread that is required. I tried to get that special thread from Crutchfield but they were not aware of the issue. Iso Acoustics is sending me the special thread that is needed. The thread is 3/8 - 16", but I believe they said I need the standard length for my Montis (not the long version). I am hoping to receive the feet and the special threads this week so that I can install them and assess.
 
I spoke with Iso Acoustics and they recommend the GAIA III for the ML Montis speaker. They informed me of the special thread that is required. I tried to get that special thread from Crutchfield but they were not aware of the issue. Iso Acoustics is sending me the special thread that is needed. The thread is 3/8 - 16", but I believe they said I need the standard length for my Montis (not the long version). I am hoping to receive the feet and the special threads this week so that I can install them and assess.
Yes, it seems the Gaia III is good for Montis. Montis weighs 26.3 kg and a set of 4 Gaia IIIs is good for 32 kg. Lucky you - my speakers require Gaia Is at about 4 times the price!

I doubt the Montis needs the extra long threads as the standard feet make contact with the thread in the base of the enclosure immediately. It's the 11A - 15A series (with amp tray) that requires the long threads. I had 13As and found the supplied threads were too short particularly if you want to tilt them forward a bit. The standard Gaias have 3 sets of standard-length threads including 3/8 -16 so you'll probably find they fit without specials. Good luck.
 
The 11A, 13A, 15A range that have amps built into their bases require a special long thread for Gaias, but IsoAcoustic now know about this and can supply "Long 3/8-16 threads" for these ML speakers. The reason is that the spike fixing holes are designed with hex shape for the first 1/2" or so to allow removal of the amp tray, so the spiral thread is set well into the hole. I hope that makes sense! Peter
Thx for the tip! I'm still messing around with moving things around so I haven't yet installed my GAIA I's under my ESL 15's. Glad I found this out ahead of trying to make my installation!! (y)
 
Any update? Did you get them installed?
While this may seem hard to believe... no, actually I haven't yet installed them. While I could list out all the things that have been occupying my time, let's just say that I have too many projects, and not enough time to get them all done. I want to get my room setup as finalized as I possibly can before I make this change (it's an awkwardly shaped room, so I am starting to learn REW). I'll get to it though, and hopefully in the next couple months... I promise... (y)
 
I recently picked up an old set of Aerius I ESLs and I found them to be a little tipsy with the speakers small footprint and sitting on the stock spikes.

I had some 3/8" thick carbon steel plates laser cut. I have holes in the 4 corners to accept 3/8" socket cap bolts that are sharpened to a point. The speakers themselves sit on some rubber isolation pucks so they don't excite the floor below.
PXL_20220312_151723193.jpg
 
Last edited:

Latest posts

Back
Top