Vibration damping obvious makes sense (in speakers just as well as in cars).
That involves 'killing' (converting into heat, through typically internal friction) kinetic energy. So any sort of elastic material (rubber has lots of internal friction) makes sense.
And then there are spikes. Using a pointy hard object and pair it with a softer, elastic material (to deform, and kill kinetic energy) can work; think metal sharp spike into carpet or wood floor.
But what is the idea behind pairing fairly unelastic metal (brass for example) with similarly unelastic (brass, stone, etc) material (example photo provided)? Only thing I can come up with: LOOKS good and makes owner feel good thinking its an improvement (works only for Audiophiles though),
Even more curious: are they ENGINEERED "spikes" (vibration dampers or shock absorbers) for speakers that are TUNED for the frequency (and mass) that needs to be dampened? Can piston style fluid dampers be designed for the high frequencies (100, 1000, 10000 Hz) using geometry, nozzles size and viscosity of the fluid?
Spikes are an attempt to anchor the speaker to the floor. They are full of uncertainty: what is the rigidity of the floor. How well dod the spike couple. do the pads that protect the floor actually uncouple. and finally, and most important, did the speaker designer intend for the speaker to be coupled. As an engineer, if coupling really was the goal, I would design something that anchored the speakers solidly to the floor.
But my experience, and this is with my speakers, other speakers may be designed differently, is that speakers perform better when UNcoupled from the floor. I won't go through the physics, but a properly designed spring is the best way to uncouple a speaker from the floor. That is my recommendation of what to try first for most speakers. Solid granite speakers might be an exception.
I agree with carlsbad 2. Spikes just minimize the surface-to-surface contact. The only good use that I see for spikes is to keep a subwoofer from sliding around on carpet. I used to have a hum problem with my turntable years ago whenever I would turn up the volume loud. I tried everything without great success. I then built a spring-loaded platform to set the turntable on and the problem was completely solved.
The principle is minimal contact surface area. The opposite of say, laying a speaker cabinet directly onto a resonant surface like a suspended wooden floor.
IMHO though these should be avoided with tall speakers unless you use some soft of outrigger. I have used them in Focal Profiles and they made the already tipsy speaker even more likely to tip over.
Prevent from moving around: accepted (double sided tape would do as well).
Nice big heavy granite/cast iron plate on the bottom, some soft rubber 'pucks' will certainly help to kill SOME vibrations (sound) transmitted from the speaker to the floor (and still keep the speaker in place).
Wondering what frequencies the crazy turntable designers calculate their vibration dampers for (and what method they use, sure mass is one of them).
The following is a Copy/Paste and very slightly edited Post made earlier this Month.
One method I overlooked to comment on and one that is well worth suggesting is the use of Spikes separating the speaker from a Suspension device. With the AT 616 Suspension Footers this is quite a easy configuration to put in place.
This Method used on a Floor Standing Speaker really pulled in the Lowest Bass Notes and the decay was the cleanest.
As I use Cabinet Speakers for listening to Blues Music, with the what to have the perception of Colour being added to the Sonic, this configuration was not my ideal, as it was a little too tidy for these purposes.
It might as a method an individuals ideal produced sonic.
I use my ESL Speakers for the most Transparent Experiences.
I am familiar with experiencing Townshend Sleds being used and the Companies Purpose Produced 'Weight Matched Plinths', there is no doubt there is a perceived improvement when these ancillaries are supporting certain Cabinet Design Speakers.
It was my introducing an individual to AT 616 Pneumatic Footers and the noticeable changes to the sonic, that encouraged the individual to investigate further suspended footers and in the end have the Townsend Weight Matched Plinths produced following the initial introduction to Townshend Products through using Sleds.
I myself can't agree that there is a Substantial difference to be found in the final produced sonic, between differing footers that offer a Suspension to a Cabinet Design Speaker.
At another time I loaned the AT 616 to my Local HiFi Group, they were used on a few different Speakers, Cabinet and ESL as well as under Valve Amps and TT's.
From the Group in attendance one followed by purchasing Gaia III Footers.
These have grown attraction as a result of the impressions being made and now most of the Group have Gaia III's in use under Speakers and in some cases Valve Amplification and a TT as well.
Again these are systems I listen to on a regular occasion and the ones that had the AT 616 in use don't seem to have produced much more than what the 616 could produce.
I am not suggesting the AT 616 is the most desirable product, I am merely pointing out that the addition of a Suspension Type Footer can have a noticeable improvement to the perceived sonic. How much one has to spend as an increased outlay to improve on a initial experience is an unknown to myself.
One other consideration that is worthy of investigation is not just the Footers but the Sub-plinth arrangement under Cabinet Speakers.
My experiences have shown that any Floor Standing or Stand Mounted Cabinet Speaker, can have the perceived sonic substantially improved, when mounted on a Two Tier Sub-Plinth with decoupling between the Floor and Lower Plinth, between Plinths and Upper Plinth and Speaker.
After trying out many materials and thicknesses of these materials, the Sub-plinths I have found to offer a lot and at not too much expense is a combination of 50mm (2")Granite and a 40mm (1 1/2") Dense Chipboard (Kitchen Worktop)
Spike Decoupling works fine, swapping out the Spikes for suspension footers under the Cabinet will create extra attraction.
kraftwerkturbo OP: Yes, tape would do the trick but elevating them with the spikes does improve the sound in my opinion. They seem to breathe better. I am not much into turntables anymore, in fact, I only have one turntable out that is not stored away, and it has been unplugged for "years" with a nice layer of dust on top!
I don't know if this qualifies as a speaker spike, but I found that using the ISO- Acoustics Gaia 1's under my Clarisys speakers to be a big improvement over just using the aluminum feet. I also added the carpet spikes under the Gaia's and found that to be an improvement.
I also use ISO Acoustics Gaia under my speakers, and there is no doubt that they improved the sound over spikes. They don't decouple fully, but work well in that direction, and, along with the likes of related Townshend products, reduce the "smear" that results from vibration, and also improve the focus of bass response.
The disadvantage, at least for some (not in my case), is that hard-coupling devices like spikes do transmit more bass energy to the floor, and some listeners prefer to have that visceral feedback, which is reduced with the use decoupling devices.
I am having second thoughts about replacing carpets with hard wood floor in my listening area after reading this thread and one other thread where low rumbles are a major problems and headaches. My wife wants to replace carpet with hardwood flooring including my listening area. To date, I had no issues from floor reflections to unwanted vibration creeping in to my audio signal path whether I played LPs or CDs. My Thiel 3.6s are on factory provided carpet piercing spikes and my TT stand also have spikes and anchored to the floor board.
I feel like 2024 is going to give me headaches we replace the carpets. I am planning to use a rug between speakers and my listening position to control floor reflections. But now I see another whole set of problems are going to creep up on me (LOL).
Spikes under speakers serve to MASS COUPLE the speaker to the mass of the floor. It helps to change the resonant frequencies of the cabinets by adding the mass of the floor to the mass of the cabinets. Whether or not it makes an audible improvement is highly subjective. But in the case of underbraced cabinets, it can help. It’s as subjective as cable lifters, mono block amps on stands, speaker cables, and component spikes. One definite advantage of mass coupling is using metal wood screws to mount a turntable shelf to the wall studs. It greatly lowers the resonant frequency of the shelf supporting the turntable.
This is my thought when trying to overcome the debate of coupling vs. isolation. My experience of having floor stander speakers on a second story suspended wood floor with carpet was a challenge. I tried spikes, no spikes, limestone pads with spikes and no spikes and Herbies gliders. The floor would pick up vibrations and transmit them causing some strange room nodes in the bass. I finally mitigated the problem by using Townshend podiums which de-coupled the speakers from the floor. So I'm a big fan of isolation at least in my situation.
Article from Positive Feedback on misconceptions regarding spikes reinforces using isolation products rather than coupling products (spikes) for improved SQ. The article’s summary and link are below. There are many good speaker isolation products such as Isoacoustics, Symposium, Townsend, etc. I personally use Townsend Seismic Platforms and can attest they perform as advertised making a remarkable improvement in all areas of SQ. Note I copied link but when I preview a graph appears rather than the link. When I click on graph the article opens. If the link does not work contact me and I will type it rather than copy it Sorry.
PF Summary:
Rigid feet couple vibrations
Vibration is a two-way street
Spikes cannot drain energy to a heavier mass
A small contact point actually amplifies vibrations
Before there was ever conjecture about spikes having anything to do with resonances, the purpose of spiking a speaker was simply to stop it rocking in reaction the motion of the drive units and to keep the speaker level. Since floors are rarely flat, spikes were seen as an economical way to achieve both goals.
Rubber has a lower internal impedance than say wood which is lower than concrete. The highest internal impedance I think is Diamond.
Spikes do nothing but fix the speaker to the floor. This is only useful for subwoofers which can creep. If you use three spikes the speaker can not shake.
The issue is bass particularly with flexy floors and walls. If the floor's resonance frequency is within the range of the speaker it is going to vibrate every time that frequency is produced regardless of what you put the speaker on, even if you suspended the speaker in air. Put a test record on and play a 20 Hz tone at high volume and walk around the house. Everything that can vibrate at that frequency will sing. You will hear a symphony of rattles. Walk around the outside of the house and you will even hear the siding rattling.
Anything that changes the speakers location in space can effect bass at the listening position and can change the speaker's sonic character. A little less mid bass can make a speaker sound more detailed as an example. Changes in location will also affect where all the early reflection points are within the room which again might change the speaker's character at the listening position.
1+ You isolated your turntable from the resonance frequency of the surface you have the turntable on and also everything above the resonance frequency of your suspension. All turntables should be isolated this way. Ideally the resonance frequency of such a suspension should be 2-3 Hz which depends on the spring rate and the mass of the suspended Turntable. If a suspension device is not tuned to the weight of your turntable it may be worthless.
Most of the stuff people put under audio equipment is purely for visual effect. If it looks cool it will sound better. Your ears and eyes are connected. You certainly do not want to put a hot amp on carpet.
Porcupine Tree (Steven Wilson's Band) has released a video of their performance of Closure/Continuation. There is also a CD of that performance. WOW!!! Gavin Harrison is a machine and IMHO the finest R+R drummer that ever lived.
And don’t forget how cheap spikes are to make. I replaced mine with the Isoacoustics Gaia 1’s and there was a large and immediate change. The current price is $500 for a set, a heck of a lot more than a set of spikes!
Another misconception: "depends on the spring rate and the mass": that is called a SWINGER for good reason. at resonance frequency, amplitude will be infinite. Try driving your car with spring only.
That is were the DAMPER comes in. Now you have a system of spring, damper and mass, and can be tuned to KILL vibrations.
This has NOTHING to do with the vibrations the emitted sound is producing ('will vibrate even if suspend the speaker in the air'). It has to do with the vibration the mass off the speaker is COUPLING to the floor (not those of the soundwave).
My listening space is on a slab, covered with a vinyl laminate. My speaker stands are on elastomer feet, no spikes. Based on how the floor isn't suspended and concrete is pretty dead acoustically, not using spikes works in my environment.
@yoyoyayaSpikes as level and holding device: no issue. But piece of sticky felt, folded paper (to level), stick on rubber would do the trick without punching holes in the carpet or floor, and complicated designs.
Spikes have become another 'pixel dust' for audiphiles (considering that people spend $100 or more for some). Unless of course. they become ART:
This is why to a damping tuned heavy load on top of the speakers and to a complex sandwich of materials under the speakers ( oak plate-sorbothane-granite plate-shungite plate-bamboo plate-cork plate) i add a set of 4 springs UNDER the damping load +the speaker weight , and to this i add a new set of springs ABOVE the speakers and under the damping load...
The two sets of springs then differently tuned by different compressive force by the difference of mass decreased resonance and improved a lot compared to a singular springs set under the speakers withoyut any coupling/$decoupling sandwich, without damping load and without another sets of springs compressed above the speakers by the load only .....
It is not doable in living room with children... Esthetic and stability problem ...
Only a a dedicated room ...
But at peanuts costs it was efficient for S.Q. a lot ...People underestimate resonance/vibrations problem , even the speakers designers...What they can do at low coast that will not appear unesthetical ?
Another misconception: "depends on the spring rate and the mass": that is called a SWINGER for good reason. at resonance frequency, amplitude will be infinite. Try driving your car with spring only.
That is were the DAMPER comes in. Now you have a system of spring, damper and mass, and can be tuned to KILL vibrations.
This has NOTHING to do with the vibrations the emitted sound is producing ('will vibrate even if suspend the speaker in the air'). It has to do with the vibration the mass off the speaker is COUPLING to the floor (not those of the soundwave).
I totally removed the spikes and only use the Gaia’s. To me, not only were the speakers not raised as high, but the soundstage really came together noticeably more. Oh and I purchased some 1 1/2” granite pieces to sit under both speakers.
@gooseI just ordered Herbie's gliders and I'm in the exact scenario of your room. What were your thoughts on them versus spikes? Our TV room is right below my listening room so I'm hoping the gliders give a little more bass isolation versus spikes.
Hello everyone. I have a new company doing specialized acoustic de-coupling products and damping pads for HiFi Audiophile and Professional Audio applications. Check out Acousti-Float.com. Bare with me, new site under construction. I'm currently looking for testers of new products at no charge to you. Please get back to me if you would like to test some of the goodies I have designed and fabricated. Very simple products but very powerful at the same time. Look forward to hearing from you. Hope everyone has a Prosperous and Happy 2024.
Isoacoustics includes the threaded rods for a lot of speakers (not KEF, but they were quick to send me the correct ones). And you would be correct. I have hardwood floors with wall to wall carpet on top, so if I uses the Gaia’s, I’d need to use their spiky things underneath and they would poke through the carpet and muck up the hardwood floor. So the granite pieces took care of everything.
Two different links to the same helpful article by Norman Varney here. IMO, the main take-aways:
1. "Couplers are unpredictable, inconsistent, and never neutral. A quality audio isolation device...will perform predictably, consistently, and neutral[ly] in every scenario."
2. "The idea that decoupling ’imprisons’ and coupling ’evacuates’ vibrations is false. Unless the vibration path is broken, or the energy converted, vibrations will be transmitted."
3. "The idea...that rigid mounting of the speaker cabinet to a heavy surface prevents the drivers from being displaced, which keeps phase constant or coherent" is "not likely."
4. "Structurally decoupling removes structural resonances, buzzes and rattles.... When the source of vibration (the loudspeaker) is isolated from the structure, only airborne sound waves from the speakers are heard. From an audiophile POV, dynamic range, low-level detail, tonality, spatiality, etc. are all improved. Everything becomes more articulate because the unwanted influences have been removed.... [Furthermore,] controlling unwanted structural vibrations can mean better-performing electronics. Mechanical vibrations can cause havoc to tubes, digital clocks, laser reading, stylus tracking, electrical contacts, etc."
OK; so why is there any confusion here?
It seems to me the reason, as usual, is that we all have different specific circumstances in our listening rooms. Simple bottom line: if you have a slab (concrete) floor, very little mechanical vibration will resonate from that floor; most of what is transmitted by the speaker will be absorbed. If, however, you have a suspended wood floor, the floor itself becomes a kind of transducer: it will resonate in its own ways as a result of vibrations communicated to it. But your wood floor is not a transducer designed by a speaker manufacturer! Therefore, whatever sounds it produces will not enhance your SQ. So you should try to minimize your floor’s contribution to the overall sound. To do that, use a decoupling device.
FWIW, I’ve tried Isoacoustics Gaias and Townshend podiums. Both excellent products. But what I’m actually using is sorbothane feet that screw into the spike threads on my speakers. Less than $100, and just as effective as either Gaia or Townshend.
@j-wall I tried the Herbies and they didn't work for me. Not bashing Herbies because I have used his other products. I'm more for Isolation instead of coupling based on my suspended wood floors rather than concrete.
Hello, looking for confirmation, I have concrete floor with pad/carpet on top, I have spikes but don't use them, the towers rest on the carpet.
My understanding from everything is this is decoupling, am I correct?
If I used the spikes provided with the speakers, they would "couple" the speakers to the concrete floor, because the spikes would pierce through the carpet and pad.
Am I understanding correctly or do I have it backwards? Thanks for any clarity you all can provide.
When working with tidying up the sonic from Cabinet Speakers and not working with the Electronics (Xover Component Exchanges, Internal Wiring) or the Cabinet Internal (Port Dimension, Internal Volume, Reflection Treatment, Bracing) , the options left are to work with external influences on the Cabinet.
Cabinet Resonance Control, along with methods employed to improve the coupling of the speakers drivers to the ambient environment, by carrying out tasks such as a Room Treatment, are the most easy to create a experience of and evaluate the methods employed.
Not every body can go down the Room Treatment route with gusto. There are usually others with a keen interest in the space to be treated. Aesthetically the materials / methods used can prove to be contentious to others being expected to embrace the presence of such additions of materials and structures to the room. Pleasing aesthetic materials/structures used for treatments will come with a cost, and might be able to be more attractive to be lived with, where others are to be present.
Cabinet Resonance Control is the most unintrusive place to start, especially when it comes to the aesthetic impact.
Cabinet Resonance Control is also a bespoke treatment and will be unique as a experience for each individual when assessing control measures being employed.
Different perceptions of the produced sonic will be found in the different spaces Speakers are Set Up in. The influence of the controls measures being employed will vary with impact in different environments. The end result being, not all experiencing the sonic produced will be in agreement that it is suiting their own personal preferences.
Hence, the inquisitiveness to create a change manifests, usually this leads to investigations to learn suitable methods to create change. As an individual becomes more knowledgeable and have a improved grasp of the subject of methods that can be employed, subjects such as the OP in this thread will be seen.
For those just entering into this subject, there is a little info that might assist with giving a better grounding (pardon the pun).
As soon as the Speaker leaves the Manufacturer, it is typically going to become a speaker that is no longer the speaker that has been designed to deliver a particular sonic. Once the speaker ends up in a new environment such a space at a Event, space at a Dealers Demo' Room or in a space within a Home. Each of these Spaces is very very different to the Space used by the designer/manufacturer during their pre-production R&D.
The same model of Speaker in all these different environments, even though aesthetically the same, will be producing a sonic that is quite unique.
'Are you feeling lucky', what is the chances that the environment one is using to set up the speaker, is as close to optimised for coupling to the speakers drivers and create a sonic difficult to be improved?
This leaves the option to try a few things out to see if a Tidy Up of the sonic being produced can be achieved. The very good news is that most who have made attempts have at some point discovered a sonic that is an improvement in their assessment.
In general the Floor Standing Cabinet can be interfaced with the room, by having a direct coupling of the cabinets base to the flooring material. Stand Mounted Speakers are able to benefit in very similar ways, but the stand mount could prove to be a compromising element in the assembly.
From this point on the methods that can be employed are not too many, but the costs associated with creating a method can vary substantially.
Spikes directly coupled to the floor or separated by being in contact with other pad material solely used to separate the spike from the floor, this can easily become a Plinth/Sub Sub Plinth using Spikes as separators.
Pads, either used to receive a Spike, or be used as the material separating the cabinet base from the floor, ( Foam, Cork, Woods, Metal, Plinth/ Sub Sub Plinth using Pad materials as separators and configurations of these in differing assemblies).
Suspension (Purpose Designed Podiums/Sleds, Springs, Pneumatic, Plinth/Sub Sub Plinth using separators that are suspension and other configurations of these)
In a room made up typically of Six Surfaces, of which room dimensions are going to vary widely and construction materials for Floor, Ceiling and Walls are going to be quite varied in their properties and influence on the speakers produced sonic. It becomes very difficult to predict which method that can be employed as an attempt to Tidy up a Sonic produced from a speaker will work to meet the individuals unique preferences in their listening environment.
As a strong suggestion, start with very affordable items to create changes to the mounting of the Speaker, these methods might just be enough for your environment, there may not be any need to extend to costlier items to function as the same role. I have this as a discipline ingrained today, even though I could immediately commence with the use of costly items to support my investigations.
When one feels that they have found a place where the Tidy Up of the Sonic has met their unique preference, there is the option to add weight to the top of the Speaker cabinet. By doing this it might show a cabinet resonance has been present . The added weight can create a reduction in audible resonance, which for some might be the desired level of Tidy Up they have been looking for.
No Room Treatments so far, but a sonic may have the capability to impact on objects present. Any ornament or similar thing that Vibrates or Rings in the room, can be bedded on a little Blue Tak, if it has to stay in the place of display.
+1 on the last three posts. To wit, @OP, compressible materials like felt or paper will not work. In fact, even a spike into a wooden floor will not work without being placed on a footer as the spike will distort the wood over time and the speaker will become unstable. As to economy, as said in the above posts, spikes are actually a very affordable and simple engineering solution to ensuring speakers are stable and level and in my listening experience they make worthwhile improvements to sound quality.
@goosei see. Mind telling me more specifically what the Herbie's did to your system, how it didn't work for you and how the Townshend's did? I've been eyeing the Townshend products, but am starting with the gliders first to see the impact. I'm hoping for some positive benefit with the Herbie's, but would like to hear your impressions.
@yoyoyaya The point of using spikes as anchors, anti slip, or 'keep level' is not disputed (even so much simpler/cheaper methods are plenty), rather their ineffectiveness as a "decoupler", "damper", or otherwise reduce vibrations.
i would even argue that putting a subwoofer for example totally flat on a carpet MAY even reduce the amount of sound emitted from the vibrating (bottom) panel (while it still couples the sub to the floor accoustically).
@zo6akSorry, didn't see that you were trying to quote someone (i.e. missing "quote marks". It was aactuall @viridian who said "Spikes are cheap, try them and they will either enhance your listening pleasure or they won't." and thus promoting the idea of trial and error for 'cheap' things instead of logic/research/physics to narrow down the field.
There are a vast range of very very affordable options that can be selected from, as a means to experience an alternative method for supporting a Floor Standing or Stand Mounted Speaker.
Spending a little money to have a new experience will certainly show a change to the sonic being perceived.
For some this one change might be the cut off point for a improved - 'tidied up' presentation. For others the addition may have been less that what was before.
Either way if no alternative methods for mounting are undertaken, not much will be learned apart from what descriptions are being read about alternative methods of interest being used by others in their environments that are most likely very very different from ones own.
The thickness of a Carpet used a Floor Covering can have a substantial impact on the sonic being perceived from a Speaker.
A friend who I assisted with investigating Speaker Footers, with the end result being they now used Townshend Weight Match Plinths under their Speakers, was so impressed with improvements their interest moved to experiencing other Speakers.
At a later date of visiting the friend to hear newly acquired Speakers purchased as a used item sale, I was to point out that the New Speakers were not as projected in the Upper Mid's and Highs as the previous in use speakers had projected.
Initially it was made known to me the Original Owner/Importer of the Speakers had a experience not like too many and was inclined to Speaker Roll. Over the course of approx' 3 Years the Vendor had owned a selection of Speakers that had amounted to close to £100K.
The Vendor had somehow chosen the route of a very cheap Glassy Hard CD Player to push on the Speakers Upper Frequencies.
My friends whole instinct and knowledge of the Speaker Designer knew much more was able to be achieved, they took on the idea of having a punt and made a offer which was close to the Drivers Value only, and the offer was accepted.
The follow up explanation given, was quite interesting and reinforced by the description also given from the designer / builder of the Speaker to my friend.
Simply put, the earlier used Speaker is a design intended to be used in Countries such as the UK where Carpets and Soft Furnishings with Heavy Fabrics are the norm. A Speaker designed for this type of environment will have a Xover design that allows for the Upper Mid's and Highs to be present and not absorbed.
In comparison the New Speakers were a Bespoke Built design Import from Scandinavia. The new owner was aware of the upper frequency roll off and had already made an inquiry to the designer. The description given, being that the Speaker is designed primarily for usage in Scandinavian homes, and if the Xover had a design to suit the UK, the Speakers sonic will be bordering on Glassy Hard in a Scandinavian Home. The designer has a Xover design in place for when such inquires are made. The initial guidance being allow the drivers further time to settle in.
My friend who is a EE and Engineer by career has no concerns about tweaking the Xover. Also they are very aware of the influence of PC Triple C Wire. I encouraged them to use this wire type on the Mid Range and Tweeter, we both agreed that a further presence of these frequencies may be perceived as being achieved iif this method is adopted.
Additional Footers in use may have also been able to lift the projection of the frequencies?
Changing a wire is very cheap to do, adding a footer in conjunction with the Townshend is only adding a little more expense, removing the Townshend? Experimentation is the only way to truly find out?
All ideas are doable before any electronics are exchanged.
For the record, prior to any suggested changes having been made to the Scandinavian Import Speakers being demo'd. I made it known to my friend that these were the best speaker I have been in front of in his room, and possibly the best Cabinet Speaker I had heard using recollections as the judge.
Not bad as an assessment when something else for the sonic is still on offer and earlier Speaker in use Speakers will have been a much more substantial in value retail purchase and the Scandinavian Speakers were acquired for much less than £5K .
You must have a verified phone number and physical address in order to post in the Audiogon Forums. Please return to Audiogon.com and complete this step. If you have any questions please contact Support.
less of course. they become ART: