Vibration Air & Roller Bearings - Thanks to Barry & Warren

[Audiophile Neuroscience]

As requested by Jud, I am posting some details of my experience with Barry Diament's "Air bearings" - and "Roller bearings" aka "hip joints" for vibration control.

---------------------------------------------------------------------------------------------------------------------------------------

EDIT (Sept 4 , 2017): unbeknownst to me, but not surprisingly, this topic has already been posted in 2015. You can read all about it, including Barry Diament's contributions by following this link:

----------------------------------------------------------------------------------------------------------------------------------------------------------------------------

 

Barry is a world class audio engineer who has posted in the past on CA. If you want to know a little more about Barry's impressive recording/mastering work,
https://www.discogs.com/artist/389175-Barry-Diament

Barry now offers downloads for those that want to sample his recordings

Soundkeeper Recordings

  (no, this is not an info-commercial but I do recommend you try one).

 

I am not an engineer and also must be mindful that this is Barry's intellectual property which he kindly shared with me. Thank you Barry! I will therefore not be elaborating on the specifications but will  try to talk in general about the principles. Much of this is covered on Barry's own website/s:

Barry Diament Audio ,

Soundkeeper Recordings

 and suggest you start here:
http://www.barrydiamentaudio.com/vibration.htm

Warren P (not on CA afaik) was the master craftsman who constructed the air platforms and oversaw the machining of the roller bearings. Thank you Warren!

 

You can see the aluminum roller bearings here - Scroll down to picture of ULN-8  http://www.barrydiamentaudio.com/studio.htm

The  "air bearings" are harder to see as Barry has incorporated them into his bespoke "Enjoy Yourshelf" racks. If I can figure out how to embed pics on this new CA board I may post some pics later.

 

As seen in the picture on the website, the roller bearing "hip joints" consist of a ball and cup design like a human hip joint (sorta). The ball bearing sits beneath an acoustically dead ceramic tile (smooth side down on to rollers) and the audio gear sits atop the tile.

 

The air bearing consists of a bicycle inner tube, inflated with just enough air to give bounce, and in my case with an mdf timber platform atop the tube.

So a sandwich of layers in my case : rack, inner tube, timber board, hip joints, ceramic tile, gear.

 

The general idea is to isolate / decouple the audio gear from ground borne vibrations.  Many isolating devices tend to couple rather than decouple movements. With spikes, shake the shelf and the gear moves the same way, one for one. Soft sorbothane pucks, according to Barry, have the wrong resonant characteristics and don’t work well in isolating low frequencies.

 

Barry's air and roller bearings decouple or float the gear in all of vertical, horizontal (and rotational planes). The tube has a vertical spring effect and the roller bearing counters or offsets horizontal and rotational motion. According to Barry, the slower the balls roll, the lower the roller bearing resonance, with isolation beginning at about 1.4 x the resonance. The longer the balls roll the deeper the isolation will be.

 

Townsend came up with similar ideas and produced expensive commercial products.

 

No, Barry, does not sell his copyrighted products (so again this is not an info commercial). You can however have a go at making your own (see above link) at least for the air bearings. It will cost a very small amount in materials. If  you are going to try this remember to place a hole in the timber platform to allow air pressure to equalize in the volume/space bounded by the inner margin of the tube. If not, air pressure would resist the up and down 'springiness' of the tube.

 

How does it sound? Barry says that it's like releasing the gear from being "bound and gagged". Across the board improvements, everything opening up, bass tightens. For me, Barry's is an apt description. Things just soared free, that sensation that the system disappears and the sound-stage for me, becomes more focused. Notably, It did NOT change tonal balance as in warmer or harsher, just more open and snapping into place, like turning the lens of a camera. Colors were the same just better seen. So, no added coloration. Barry explains that isolation should not add to the sound but rather prevents the harmful effects of vibrations, thereby preventing coloration if you like, closer to neutrality. It takes you one step closer to transparency and paraphrasing Barry, your system getting out of the way of the music.

 

Apologies to Barry if I have misconstrued or wrongly explained things.

 

David

 

[ Comment all you like but as the Poster, and in deference to Barry, please keep it respectful. Thanks]

 

[Audiophile Neuroscience]

1 hour ago, AnotherSpin said:

I believe Barry Diament's ideas on this topic were discussed here earlier already and in certain length and some of CA participants shared their experiences with air tubes and bearings. Barry himself took a part in it. I went through intense passion with all this as well (and Barry was exceptionally kind and helpful in explaining things in PMs).

 I didnt know that. Hopefully this thread may spark interest for those that did not see the previous post.

Exceptionally kind and helpful is a good description of Barry !

[Audiophile Neuroscience]

7 hours ago, rando said:

This is the lengthy main discussion (there were numerous others that pulled information from it) AnotherSpin was referring to.

 

I don't have the administrative ability to close this thread but perhaps it may serve a purpose by redirecting people to the main thread here:

 

[Audiophile Neuroscience]

1 hour ago, rando said:

My preference is tackling whatever sparked you to start a side conversation here.    

 

No problem, I guess raising the same topic every couple of years is not a bad thing. Well that would seem fair considering how much some other topics get recycled. It is also so (relatively) simple and inexpensive and easy to try for DIYers.

1 hour ago, rando said:

Consider me smitten with the initial results.  The idea of throwing an old bike tube and some bearings under a piece of equipment rapidly appealed to me as I have a large supply of both.  Following the holiday weekend store closures I plan to go about this more seriously.  With 35 pages of the aforementioned thread left to browse I have any number of revisions to my rough sketch that may occur.  This is honestly one of the more exciting audio developments for me lately!  

 

You'll be even more smitten when you get it all properly set up!

 

1 hour ago, jabbr said:

Many people use little pieces of polymer etc around or to hold various components, boards etc, but none of this works nearly as well as the type of vibration isolation being discussed here with rollerballs and inner tubes.

 

I agree, bracing or lashing something down may  reduce the magnitude of the oscillation but is not true isolation as I understand it. In some instances it may also just serve to couple the vibration to the device.

 

 

[Audiophile Neuroscience]

1 hour ago, fas42 said:

My mindset is to fix the problem at the source - would you prefer strong bones; or soft ones, which meant external crutches and mechanical aids to support the body?

 

Fas, I believe you misconstrue things here. If you were to fix the problem at the source you would need to stop the vibrations at the source, like stopping the trucks going down your street, or moving your speakers away.

 

Your analogy of mechanical aids for the body is IMO not applicable. Whether applying some kind of internal bracing or externally isolating vibration you are striving to prevent said vibrations entering "critical components". We are not trying to beef up that componentry, just stop vibrations reaching it.

 

If you lash down the housing containing the components, you simply create a pathway for the vibration to get in. You couple the external movement to the inside part in a one to one ratio. Move the outside housing: Move the part. This is also why things like spikes and cones are not as effective as people think.

 

 

1 hour ago, fas42 said:

Think of the suspension for a car wheel - elastic properties combined with damping properties give the best results here, and I find that also in audio parts.

 

Somewhat oddly I believe this reasoning is more sound but IMO it does not support your own premise (that's the odd part).

 

It is precisely the *elastic* springy qualities of an inner tube that is being employed with Barry's methods. It isolates, depending on resonant damping properties and so on, like the suspension on a car - in the vertical domain.

 

Similarly the roller balls provide damping but in the horizontal and rotational planes.

 

Think of it this way. As the ground moves beneath the equipment, the equipment maintains the exact same position in space, it doesn't move - the ground does. It is damped or isolated from such movements. Lash the equipment down and you will ensure both move together - coupled, non elastic, not damped.

 

 

 

[Audiophile Neuroscience]

1 hour ago, fas42 said:

elastic properties

 

17 minutes ago, fas42 said:

The word is, "viscoelastic".

 

You used the word elastic (combined with damping). If you wish to correct yourself that is fine.

 

I am familiar with the term. Just because 3M or whoever markets its properties for damping in certain situations doesn't mean it works well in audio.

 

Sorbothane has viscoelastic properties but once again, despite being employed as isolation pucks in audio, afaik it does not have the right *resonance characteristics* and *doesn't isolate lower frequencies*. I mentioned this in the original post. "Silly putty" also has viscoelastic properties but doesnt make it necessarily suited for what we are talking about.

 

Springs have resonant and elastic properties and can also have viscous damping.

 

In another thread I politely pointed out you were using Auditory scene analysis and Mismatch negativity incorrectly, IMO. That was more up my alley than this topic but I think as Jabbr said

2 hours ago, jabbr said:

Ok you are just being totally random here. What you are talking about has nothing to do with this thread about vibration isolation.

 

 

40 minutes ago, fas42 said:

I know it don't come easy ...

 

Phew, at last we agree on something, lol !

[Audiophile Neuroscience]

12 minutes ago, fas42 said:

preventing very low frequency vibrations reaching the equipment. And what I do will have zero effect in that area, there is no overlap - personally, I have never intentionally attempted to isolate with those techniques, because I have achieved the goals using other approaches.

 

Fas, if you have never tried isolating low frequencies (you said "what I do will have zero effect in that area") why not try Barry's ideas. That's really what this thread is about. If you have tried isolating low frequencies (you said  "I have achieved the goals using other approaches") then feel free to elaborate.

12 minutes ago, fas42 said:

My apologies for disturbing the flow of this thread ...

No apology required. Nobody minds respectful debate and disagreement.

Cheers

David

[Audiophile Neuroscience]

12 hours ago, AnotherSpin said:

I put all my equipment, including heavy 35 kg each speakers and tube amp on bearings and bowls.Tires too. It worked, no doubt. I liked the change in sound. At the same time I should admit, it is not convenient to have everything moving around. Lightweight components (as mac mini, for example) were not staying in place. Sturdy interconnects were an obstacle. As an experiment it is fun to try, but to use it permanently was slightly over the top. Since that time I downsized to much smaller and modest sound set, and it makes no sense to follow-up with bearings/tires. So, my recommendation is – if you have big heavy high-end components, you would try with it.

 

I have a slightly different 'spin' on this, Spin (sorry)

 

My intuition and limited experience is that this whole approach most likely works best for smaller, lower mass/weight equipment, especially in relation to air bearings.

 

The issue is that high mass requires stiffer springs or less supple rubber inner tube to support it, thus limiting its effectiveness. Eular springs might be better in this respect as per Jabbr comments. Also http://gravity.physics.uwa.edu.au/amaldi/papers/Winterflood.pdf

 

In the case of roller bearings higher mass with more inertia present their own different problems. I am not a physicist so these are just thoughts not facts. It seems that higher mass 'grinds' down on roller balls moreso thus limiting their effectiveness. The solution might be bigger balls and cups. However the actual point of contact of the sphere on the surface of the bowl is probably not that much less ie Force over area = pressure may be similar. As I say its just seems intuitive somehow (to me) that bigger balls/cups would be required for large mass devices.

 

OTOH the larger mass with more inertia may be more naturally resistant to low force displacing vibrations so maybe its less important to isolate them....except ,presumably it is the (low mass) inside components that one is targeting. I dont have the answers.

 

In the case of *very* lightweight gear the main problem I see is the effect of stiff interconnects skewing and tethering the device and antagonizing the isolating effect of roller bearings. This is at least partially countered by judicious placement of interconnects so that 'the wobble factor' returns.

[Audiophile Neuroscience]

8 hours ago, rando said:

Bicycle tubes are not a great long term solution as they are effectively porous items that lose air with greater expediency as pressure rises.  My road bike tires, at 95 psi, lose up to 10 psi over the course of 24 hours sitting stationary.  Euler bearings are substantial and complicated industrial solutions for the most part

 

Yes, I believe others have found inner tubes fiddly in that they require periodic re inflation. The real hassle though comes with the need to replace them when they inevitably perish.This is not bad if you have light gear but my amp weighs 108kg!

 

My craftsman friend Warren arranged a pair of "bottle jacks" and fashioned adapters to work as "tow jacks". Worked a treat to place the air bearing platform beneath the amp.

 

The advantage of a tube over Eular springs is that the tube can be infinitely adjusted by inflating or deflating. If you find some way of accurately measuring the pressure you can calibrate what is ideal. Barry says he can hear changes in the sounstage as he leaks air out of the tube.

 

C'mmon guys, what could be more cool and nerdy at the same time. Imagine a group of spectators as you launch yourself from your listening chair saying, "ahh I think that needs just another smidgen of air pressure...ah, that's better!". Divine madness, but we need some reintroduction of the whole 'hands-on' experience in audio since few of us now have tonearms to fiddle with or records to clean. Am I wrong?

 

[Audiophile Neuroscience]

6 hours ago, rando said:

Among the troubles the simple air bearings he mentioned highlights is using a round tube under a rectangular platform.  Taking a rectangular piece of equipment with uneven weight distribution and replicating it's dimensions into an outsized shelf which it is placed onto off center to create equilibrium strikes me as poor implementation and design.  This is not how you make a foundation.

 

There is no inherent problem placing or balancing a square platform over a round inner tube (if you like you could make a round platform). I agree that most equipment will have uneven mass distribution but it is easy (in my experience) to adjust the position to effectively balance  the gear sitting atop. Barry, himself doesnt use air bearings under his speakers and I think the higher centre of gravity would make that challenging to balance safely.

[Audiophile Neuroscience]

16 minutes ago, fas42 said:

the cups have to be kept pristinely clean - dust settles in the most important spot, and the benefits slowly degrade, unnoticeably. A maintenance regime is therefore essential.

 

Too early for me to say as I have only recently installed them. He has DUST in his music room ? Shame !

[Audiophile Neuroscience]

1 minute ago, rando said:

Plebeian and low rent!  True audiophiles know the Wilson Audio Flat Jack as the only tool worthy of mention for any task of this order.  

 

HaHa, yes we explored many sorts of lifting devices and cranes! These wilson jacks look a bit like "trolley" jacks. Happily. Warren's solution was a fraction of the price and more stable (the fixed adapter being placed along a greater surface area of the bottom plate)

[Audiophile Neuroscience]

can someone briefly explain the "xyz reacted to your post" notification. The green symbol alongside that post has "upvote" "like" (grayed out) and thanks (grayed out)

[Audiophile Neuroscience]

7 minutes ago, fas42 said:

Fine dust particles are always floating around, unless one has an IC fab room. And they will always settle into the lowest point on a smooth surface, especially if subtle movement keeps disturbing them - almost invisible, but a thorough clean up immediately reveals better performance.

 

makes sense. I wonder what others have found.

 

I have hospital grade sealed and suctioned clean air environment in my dedicated listening room. Doesn't everyone?

[Audiophile Neuroscience]

9 minutes ago, Ralf11 said:

 

 

I highly doubt many on here do that.  Most have chip fab air handling.  Hospitals are dirty and dangerous.

 

Well some compromises need to be made. I also gave up on wearing those full body contamination suits as it went against the audiophile's creed that one must sit naked while listening to music.. The bass waves resonate certain jiggly bits of anatomy and improve SQ !

[Audiophile Neuroscience]

26 minutes ago, Ralf11 said:

http://newatlas.com/subpac-m2-wearable-audio/39920/

 

 

Just ordered mine. Best results are obtained sitting on it (naked of course).

[Audiophile Neuroscience]

2 hours ago, AnotherSpin said:

In my system best effect was achieved by using bearings under heaviest components (speakers).

 

What size were your roller bearings and cups?

[Audiophile Neuroscience]

Just some additional thoughts about damping,isolation, and resonance.

 

These are tricky concepts (for me) to truly understand and their inter-relationship. I may have used "damping" in a way that suggested it was desirable, basically meaning any sort of thing that reduces the effect of vibration.

 

Damping and isolation can both be used to manage vibration but they have different meanings and in the context we are talking about, damping is not desirable.

 

As Barry puts it "It is not desirable for an isolator to provide damping too.

To be clear, there is an inverse relationship between the degree of damping and the degree of isolation.  That is, the greater the damping on isolator motion, the *less* steep the rolloff (i.e. the less isolation) above the isolator’s resonance.  In the case of a roller bearing like a Hip Joint, we want the ball to roll as slowly as possible (lowest resonance frequency) and to continue to roll for as long as possible (*least* amount of damping for steepest rolloff above resonance).  Similarly with an air bearing, the more supple the material, the less damping on the bearings’ isolation."

 

To quote another engineer

Isolation is a reduction in the ability of a system to react to an excitation. This is achieved by the use of a flexible decoupling element between the equipment and mounting surface. It allows the inertia of the isolated component to oppose and thereby reduce the vibratory motion transmitted to the support.

 

Damping removes energy from a system by converting kinetic energy into heat energy (in the case of conventional shock absorbers, for example)

 

Every isolator has a peak resonant frequency below which transmissibility is almost unity and above which attenuation occurs. However, should the natural frequency of an isolated system coincide with the forcing frequency then resonance will occur i.e. amplification of vibrations. In this case, damping is required to reduce the amplitude of the resonant response by removing energy from the system.

 

The ideal isolator would have as little damping as possible in its isolation region and as much as possible at the systems natural frequency to reduce amplification at resonance – this is clearly not possible with standard damping systems.
If there is no resonance present in the important operating frequencies of a system then damping can actually make things worse as it leads to a loss of isolation efficiency. The damper will act somewhat like a strut and vibrations are then transmitted to the isolated element. For example rubber is not an ideal isolator as it not only has isolation properties but also some damping properties inherent to the material. This can increase the transmission of non-resonant vibrations.

 

 

[Audiophile Neuroscience]

20 minutes ago, rando said:

Some interesting stuff going on in the Trio/BBS rack

 

from their website, " spike point support (contact area has been minimized and kinetic energy turns into heat) have been combined with the effects of deadening vibrations owing to to sliding friction and rolling resistance. "

Resistance and friction doesn't sound right to me as achieving isolation but I could be wrong!

[Audiophile Neuroscience]

32 minutes ago, rando said:

I'm having a slightly hard time picturing your idea John.

 

As am I. In my case, it's a 'it's me not you' kinda problem.

 

To be honest I also stared at the descriptions on Ingress engineering and for the life of me I do not get what "blocks" are and what goes on *top* of a device. The "footers" appear to be just the 'cup' part of a roller bearing. Most pictures seem to show 'cups' and ball bearings .

[Audiophile Neuroscience]

58 minutes ago, JohnSwenson said:

The level 2 system consists of two "blocks" per support location. Each block has a highly polished spherical depression. You put a ball in the depression, and put another block upside down on top. The level 2 ones take a 3/8" ball. The top one just flops around on top of the ball until you put something on top of a set of three. The top block then "levels out" on the under side surface of the supported device. As the blocks move relative to each other the ball is rolling between the the two curved surfaces.

 

This particular system has a very small amount of play, so as you turn knobs, push buttons etc, it can't move very far which doesn't feel too wobbly. The isolation is still effective because the actual displacement for real seismic noise is VERY small.

 

I prefer to use them with a flat plate on the top, this halves the resonant frequency, which is good for isolation, but it allows for more motion when your hand is moving things.

 

A set of level 2 supports contains 6 blocks, using two for each support location (assumed to be a triangle), with a single ball for each set of two.

 

When I got mine they did not come with balls, I ordered some from McMaster Carr. I got both 1/4" and 3/8" chrome steel balls, for the two block approach it has to be the 3/8, for the flat top approach either works but I preferred the 1/4".

 

When going with the flat top you only need one block per location so you can do two platforms for the price of one!

 

Thank you John for this explanation.

 

In effect the top block forms a support platform of sorts for the component.Not being a flat surface I would anticipate that it also restricts roller ball motion, less than ideal for achieving the least amount of damping of isolator motion to achieve the steepest rollof above resonance.

 

OTOH one cup (and ball) is required beneath the component for practical purposes, not the least preventing the gear from rolling right off the shelf or knock into something else, defeating isolation.

 

I must say, for me, Barry's approach is elegantly simple, many great things are. I have now used multiple air and roller bearings under reasonably heavy gear as well as very lightweight eg LPS1. My interconnects (gryphon guideline) are stiff but I have been able to mange to maintain the 'wobble factor'. I dont find the springiness of the inner tubes to be a stability concern nor the roller bearings.

 

Barry's idea regarding the support platform is to achieve maximum rigidity with *minimum mass*, and thus the use of a relatively light weight acoustically dead tile, rather than heavier metal platform.

 

It would be interesting to see how these different approaches measure.

 

Cheers

David

[Audiophile Neuroscience]

43 minutes ago, rando said:

 

Try the petite section and ask for AAA cups.  The radius should be near optimal.

 

More wearable audio? Make sure you get a matching coloration with the bass vests

[Audiophile Neuroscience]

4 hours ago, rando said:

Can anyone explain why Barry chose to leave the forum?  

 

I have not read the original thread yet but perused the last several pages. I note that 'words' were exchanged with a couple of the participants. Notably, I saw hints  that Jud and SandyK were aware of Barry's leaving with Jud saying he could speculate why but I guess wisely, did not.

 

I have had the good fortune to 'meet' a number of wonderful people through CA.Two of them I have remained in contact with before and after I left CA a couple of years back. SandyK who I have met in person, and Barry with whom I have periodically corresponded . Barry recently viewed the eclipse and SandyK (Alex K) will hopefully get reconnected to the internet tomorrow ( i got an sms from him Tuesday)

 

I will not presume to speak for Barry but will simply say, IMHO, his leaving was a great loss to the audio community at CA. He has been and continues to be extraordinarily helpful and kind to me when I pester him about all things audio.I have in fact set up my entire listening room based on Barry's recommendations which nearly always accords with my own research, my limited understanding of physics (first year University level) and my somewhat better understanding of perceptual processes and the human mind.His recommendations just work, in my experience improving sound quality.

 

I am guessing Jud is watching this thread so just curious, why did you suggest I kick this thread off knowing vibration isolation had been previously discussed?

 

David

 

 

 

 

 

[Audiophile Neuroscience]

11 hours ago, rando said:

The subject of his departure coming up in the last few posts of that thread in no way implied it was ascribed to something occurring in it.  Thank you for clearing this up for me and I agree it is a loss.  For better or worse, industry vets face an uphill battle here.  

 

Is anyone aware of a currently on the market roller bearing design that works better than one that was forwarded by BD?

 

 

 

 

 

There are no posts from Barry in the last several pages of that thread so one can only speculate about what happened by reading the pages around the time he 'left'. Certainly there was no hint on the last pages of why, just people noticing he was not there.

 

Yes, I fully agree that qualified and experienced vets like Barry have not always got the respect they deserve in fora including CA. I will say though, in the 2 years I have mainly been absent there is a conspicuous reduction in the amount of trolling by 'armchair experts' and sarcastic bickering. I noted Chris put an abrupt end to such an exchange in another thread recently.

 

No expert worth their salt expects not to be questioned or challenged.It is the way in which it is done! I will say for the record that Barry has the most patience, even and gentlemanly manner of anyone I have come across in this forum. he constantly affirms that he would never deny the sensibilities and experiences of others that leads to their particular enjoyment of music, however derived. In fact he goes out of his way to be accommodating.

 

That said he is, as I know him to be, a gentle and kind, passionate and sensitive human being. Yes, we can speculate why he left but IMO its not hard to connect the dots.

[Audiophile Neuroscience]

11 hours ago, AnotherSpin said:

12 hours ago, rando said:

 

Is anyone aware of a currently on the market roller bearing design that works better than one that was forwarded by BD?

 

 

I do not know better or not, but these are quite reputable - http://www.symposiumusa.com/allproducts.html

 

 

This website smacks of hype to me. There appears to be marketing spin woven into some truths which always makes me wary.

Admittedly I have not studied ALL of their information.

 

The mixture of isolation AND damping concerns me. The " simultaneous coupling and decoupling of audio " and "draining" the mechanical energy. Other stuff like their explanation of how spikes work, " spikes provide an escape route......funneling energy to a point and forcing it to encounter the support structure at an angle of 90 degrees, the optimum approach angle for energy transfer" . Pathways work both ways and from my understanding of forces 90 degrees would produce no vector force translation so it seems it would follow, no energy transfer.Again I am not a physicist or engineer.

 

It is entirely possible they work but NOT for the reasons or hype as advertised.IMO I come across similar scenarios in Medicine regarding "alternative" treatments. What more specifically concerns me is that the blocks have multiple bearings on the bottom "to ensure good support". 3 points of contact would appear ideal with more just complicating matters and maybe a source of chatter. The actual cup does not appear large enough in relation to the ball size to provide adequate space for the ball to have long slow excursions as required to be effective. Does anyone know their cost?

 

The Ingress ball and cups as mentioned earlier seem better to me.

 

The ball and sockets (cup) that Barry devised requires some hunting to find a machine shop and someone knowledgeable enough to oversee the quality of the machining to spec.My friend Warren was ale to source a supplier that was up to standard, after a couple of failures. 3 of us (myself,Warren, and Peter (audiotruth on CA) ordered, from memory, 100 cups ie 33 pieces each enough for 11 sets.All high quality and highly polished aircraft grade aluminum. It cost around $30US per set (of 3). Barry once told me he initially got some outrageous quotes but was eventually able to also get sets for a most reasonable price. Others have mentioned that Barry gave the specs in the old thread. The finished product comes with the 'guarantee' that Barry spent large amounts of time and research into their production, a man who is a perfectionist at his audio-engineering craft, and has an astute experienced audiophile ear.