mike_mccue


Matt, you are a true gentleman.

And your input on the subject of resonance has been a great contribution.

best,
mike

I'm always happy to admit when I am wrong, though sometimes it can take a while before I realise I ultimately just want to get down to the answer and discussions like this are what do that for you! Thanks for the kind words. I greatly appreciate your contributions.

A while back we bought some Vandersteen speakers for our entertainment system from an audiophile store.  While they are not "pro" they are great reference speakers, and in the world of audiophiles they have a pretty good reputation.

Why would you say the Vandersteens are not “Pro”.  I have a set of Vandersteen 2ce’s that are in storage now but were/are one of the best pair of speakers for the money that I have ever owned.  I have recently started kicking around the idea of setting up a separate pseudo-mastering system and incorporating my Vandersteens as one set of reference speakers’

At some point (either from an engineering or monitary standpoint) the design goal of studio monitor and the “consumer’ speaker merge (I know, I will probably get a lot of flak for that one).  It is not uncommon for mastering houses to use B&W’s, Wilson’s or ProAc’s.  Granted, they are typically hi-end speakers, but speakers that none the less find a home in both consumer and professional listening environments.  

As a side note, I have a small collection of vintage mid-fi speakers and of these one of my favorites is a model by EPI.  Recently, in the course of doing some online research to see what people are using in their pro studios … I’ve come across the EPI model 100’s (and yes, even Vandersteens).  I think the point I want to make is that you have to judge a set of speakers on its own merits and not just the advertising hype.

Jeff, I didn’t quite understand this statement … if you already addressed this, please point me to it, this thread is starting to make my brain hurt:

And FYI Mike there is no vibration in the stands of any sort. Even when the speakers are putting out serious volume and low frequencies, the stands are absolutely vibration free. All the way down from right under the speaker to the floor. So there is no vibration transmission into the floor either. I think that was what Dave was talking about. Resting the speakers on a surface that is holding the speakers rigidly in place.

Just to add something to the discussion about the mass … I always thought the working hypothesis (or myth) for the sand in the stand was that it acted as a limp mass or in other words, its purpose was to convert low frequency vibrational energy to heat.

WRT transmitting vibrations to the floor … how effectively you want to couple or decouple the stand from the floor probably depends on the nature of the floor.  Myths / hypotheses on the topic of floor – speaker stand interactions that I have heard over the years include:

Coupling the speaker to a concrete floor via speaker stand spikes essentially creates a massive and heavy speaker cabinet partially made of concrete which is a good thing

Decoupling (or at least lossy coupling) of a stand from a wooden (on joists) floor using a damping material between the stand and the floor is a good thing because the wooden floor can resonate at low frequencies.

Jeff, if you put the spikes on a rickety old table... you don't have to blame the spikes. ;-)

So what were your speakers on?

You've indicated that they weren't on a desktop, tabletop, shelf, or console...  were they on peach crates or something?

Hi Mike. I should clarify, sorry. My experiments with spikes was during my monitors on the table period The table is a solid metal frame with a fairly think piece of timber on the top (20mm or so) It is not rickety at all. Right on the left and right front corners (over the steel legs) I had a concrete slab about the same dimensions as the bottom of the Mackies and about 6 " high. The Mackies sat on a wooden piece of timber that had the spikes imbedded. So the four spikes were in contact with the concrete riser underneath.

I think I needed more room on the table so the monitors went off to a structure behind. I did my best to make that as rigid as possible but I would say as the sound is so different now I did not achieve it.

I am not putting spikes down at all. I am sure there are other reasons why the table moved a bit under 40 Hz tones. But it moved too much right in the middle of the table. Bit like a drum head suspended over a hoop eh!

If you have spikes at the lower end of a high stand and the weight of the speaker at the top end acts as a support then the column(s) that are holding up the monitor plate could move even more so. It makes sense. The column becomes alomost like a guitar string resonating at certain frequencies. Bracing the columns (or one large column) all the way up and filling them (it) with heavy material could be a similar way to achieving the sort of deadness a concrete stand might have.

The big thing though is as the bass has changed quite a bit, it has exposed the mids and the highs too. Like I said in my OP it is like I have gone out and bought another pair of speakers. I am still getting used to how the mids and the highs are sounding now. I am listening to known reference and very well recorded and mixed material to try and get a feel for how the monitors sound when the mix is really good. It is going to change mix decisions very much so. Almost more than any plug-in or software update. It just still goes to show we owe it to get the best possible monitoring sound we can given our environment. I read with interest other threads that talk about bass traps and that is probably the next area of interest for me and maybe controlling some reflections too with some more absorption and diffusion.

Dave,
 What would you put under the spikes?

 Floors and Ceilings etc have ratings for lbs/sq in pressures.

 Concrete is not a wonder material... it wants to crack and crumble... we use the reinforcing steel to provide resistance to tension.

 Spikes and 1000 lb Air Handling units may act a lot like a slow motion jack hammer. would the spikes have big metal pads? How much do they weigh? Would that be chasing your tail, engineering wise?



 On the other hand... you may be familiar with the fact that factories are often stuffed with heavy vibrating equipment and most of it is sitting on steel feet with small yet strong height adjusters.

http://www.directindustry...achine-feet-B-299.html

 So why aren't they all embedded in big concrete foundations? Probably because it doesn't matter.

 Kinda like why I think the Air Handling unit example is not likely to be a definitive example of something an engineer considered and dismissed... I just don't think the subject comes up that often.

 I haven't lived in a concrete floor house since 1983... so perhaps I am biased towards the spikes seemingly working while they may not be as effective on concrete.

 The times I have used spikes on a slab floor I feel there was still improvement over the choice to leave the speakers on the floor. In other words, the spikes never seemed to hurt.

 If the spikes DO result in more measurable vibrations in the stand ( I assume the spikes are on the base of the stand)... doesn't that seem to correlate with the the very basic idea that spikes do not transfer the vibrations to the supporting surface? Some see the vibrations as a problem... whereas I don't see them as a problem (mainly because I think they are the minute sort of thing you measure with an accelerometer or piezo) if it helps prevent the energy from being transfered to some resonant material or structure down the line.


 Anyways, just random thoughts.

 best regards,
mike
 

Thanks Dave.

I think I followed you all the way... and then got to the rubber feet and thought ... No Duh!

I like the rubber foot idea as well.

The "up turned cones" confuse me. I'm only familiar with the pointy side down variety.

How about rubber cones pointy side down?

He could just as easily explain that cleats are meant to prevent slipping.

I don't buy all that mumbo jumbo.

So I use the Brilliant Pebble method.

http://machinadynamica.com/machina31.htm

Because it would sound so good it would scare you......

That site is funny as hell.  At first, I thought they were serious.  But there's just no way...the more you read, the more you realize they're making fun of audiophiles.

I think.....I mean.....you CAN buy the stuff they're selling there.  I guess if you're dumb enough to think that four bowls full of water, strategically placed in your room will make it sound better then you probably deserve to get fleeced.

Then, there's the Teleportation Tweak:
http://machinadynamica.com/machina60.htm

LOL....just BRILLIANT!

Those crystals are a waste of money - unless, of course, you also augment them with the studio-grade outlet covers.

I'm going to go puke now...

Let me know if it vibrates anything.

I don't buy all that mumbo jumbo.

That site is funny as hell.  At first, I thought they were serious.  But there's just no way...the more you read, the more you realize they're making fun of audiophiles.

Just playing Dr. Phil here but it sounds like Skull has a deep rooted hatred of audiophiles or possibly a phobia (audiophilephobia) ... or MAYBE ... he is actually a closet audiophile

Mike old buddy... this may be the first time we're on opposite sides, at least sorta!

There is a TON of phony science associated with all aspects of audio... my current favorite being the $300 power cords, but that's a topic for another day.

You are right about quasi-science being a problem, but in this case there is some real science with respect to mounting monitors rigidly.

However, the single biggest benefit, for most people, to mounting near field monitors on stands is correcting the relationship between ear and monitor - you can more easily mitigate bad reflections when you can move the stands about the space freely.

That said, studio designers have been jumping through hoops to mount monitors as rigidly as possible to decouple them from the physical room for a very long time now. It has not always been the case.

I remember the little "Tip Toes' cones, and all the other silly gadgets... this is different.

I've been using sand filled stands for my near fields for about 15 years. When we moved five years ago I had to empty them. I decided it was silly to fill them again, so I didn't. At first I assigned the differences I was hearing to the new room, which was largely untreated. I spent some time chasing my tail, and then I filled the stands with sand again. It made a difference.

My big monitors are also mounted on sand filled stands, but they are dog-housed as well... or they were till I moved<G>. Still don't have them back in service... ugh! Obviously that's a horse of a different color, but it made a difference in every studio I've ever worked in.

So why?

Good question, and I don't have a definitive answer. I'm also pretty sure it's a 5% solution, meaning if there are other issues with the space they will swamp any benefit you might gain - not unlike symmetrical power distribution.

I think there are two factors at play:
1) it greatly reduces transmission of energy into the floor. Now if you are already on a concrete slab that probably does not amount to much, but if you are on a wood framed floor it could be significant, especially at low frequencies.
2) it reduces the speakers ability to move. I think this gets exaggerated emphasis, but I think it is real. If you are playing a loud mix and the speaker cone is moving then the speaker cabinet is going to want to move in the opposite direction, although given the difference in masses it is not going to move much<G>! Still, it wants to move as a reaction to the cone moving, and if you can stop it from moving that has to be good.

There are, of course, other ways to accomplish these goals, but a sand filled stand is a good cheap way to do it - assuming you remember to glue the sides together carefully... don't ask!

I also like the idea of sand...

I like that idea too, maybe we could market sand made from grounding down Skull's magic crystals.  Then even use it in a special audio stand concrete mix.

Pointy down cones (to use their more scientific nomenclature) sound more likely to me too, pointy up ones would work like a trumpet wouldn't they?

But having my bare feet in a tray of warm sand while I'm mixing has got to be the way forward.

I think filling the room with thick smoke also will help bring them ol' speaker motors to a quicker halt too.

In fact to hell with the mixing, I'm having too much fun in my padded cell already.

Now what to do with all this aluminium foil?

I like the idea... but how would I pick the right sand?

I would suggest that builders sharp sand would act like a brake and therefore be more liable of transmitting vibrations to the next grain, whereas soft sand would dissipate the vibrational energy more efficiently.

But then again the reverse could equally be as true.

But I'm not going to be taking any chances now.

I'm going to put some rubber matting on top of concrete pillars which I shall stand in a tray of soft sand which will be supported by downward pointing conical spikes.

And knowing my luck this will cause my enclosures to start rattling themselves apart...

And as any self-respecting cockney audio engineer will tell you 'it's all abaht va sahnd'!