[Danny Richie]

Hey AJ welcome to the party.

Yeah, if you don't have two speakers there it A/B on the same system then you really can't make much of a comparison.

In drag racing we called it bench racing. You could add up all the numbers and think you have it all figured out as to which car will win and think it might as well be written in stone. Car A will out run car B. Then when it comes down to the real race car B gets to the stripe first. That's why we run the race.

[AJinFLA]

But as you well know Dan, it's often quite impossible to bring a pair of your speakers into the Magico room and saying, hi there, would you mind playing these?

cheers,

AJ

[jtwrace]

But as you well know Dan, it's often quite impossible to bring a pair of your speakers into the Magico room and saying, hi there, would you mind playing these?

cheers,

AJ

If you never try you'll never know...

[HT cOz]

Do you guys have any holy grail moments?  Such if this tweeter would just do X then this would be perfect?  Or if the woofer would only do Y then I wouldn't have to compromise. Also as a two way there seems to be a problem of wanting low extension but then running into beeming because the woofer is to big. So you use a smaller woofer but then... Etc

[Danny Richie]

But as you well know Dan, it's often quite impossible to bring a pair of your speakers into the Magico room and saying, hi there, would you mind playing these?

cheers,

AJ

YG Acoustics was promoting some head to head comparisons not too long ago.

There are ways to arrange things like that if you know people.

[AJinFLA]

YG Acoustics was promoting some head to head comparisons not too long ago.

There are ways to arrange things like that if you know people.

Interesting. At shows? Dealerships? In home??

[Danny Richie]

Interesting. At shows? Dealerships? In home??

If you know the people pretty well you can have some after hours comparisons at the shows. Those are usually pretty private. I have done this quite a bit with non-speaker related gear mainly.

If you know dealers    You can arrange some comparisons that way. So I have had a few in store comparisons. 

Then when you know people or customers that own speakers XYZ they can bring them over for comparison, measurement evaluation, etc. That has happened quite a bit actually.

And once when doing design work for another company, they had some competing speakers flown in for comparison.

Lots of good information can be learned by making comparisons.

I have even hosted some shoot outs.

[aron944]

Glad to see this discussion! I think when it comes to top tier mini monitors (not sure how mini we are discussing) it is clear that at the very minimum either an exotic material/manufacturing process or an exotic shape, or both are desired in the market place.  Someone previously mentioned Magico and they have done both it seems, first the stacked ply with an exotic shape, and now with their aluminum construct. Sonus Faber, with their teardrop shape uses solid curved wood, stacked and ridiculously thick . TAD with their CR-1 uses a hybrid cnc ply, mdf, and aluminum.  The list and the technology goes on. How much of the complexity is warranted from an engineering perspective I am not sure, each manufacturer claims theirs are the best for reason x, y, or z.  Visually they are certainly appealing, curves are nice, but an angular creation with double thickness walls, would maintain 99% of the benefit and reduce 85% of the complexity and cost.  A deep trapezoid would prevent parallel surfaces and provide the depth that Danny referenced previously.  Double thick walls give the rigidity needed, etc.  Btw, I think small towers count, I think folks that are serious about their sound typically purchase mini monitors for cost, not space considerations, if they could purchase the same speaker in tower form they would but the cost of the exotic cabinetry takes its toll.

[Danny Richie]

Thanks for posting Aaron.

Speaking of the TAD Speakers. They make the best sounding stand mounted speakers that I have heard at a show.

[Danny Richie]

Do you guys have any holy grail moments?  Such if this tweeter would just do X then this would be perfect?  Or if the woofer would only do Y then I wouldn't have to compromise. Also as a two way there seems to be a problem of wanting low extension but then running into beeming because the woofer is to big. So you use a smaller woofer but then... Etc

The first holy grail moment that comes to my mind was when I first listened to an OB-7 prototype and was struck by the open baffle mid. It goes right back to the discussion of coloration caused by the box. As soon as it was gone I knew nothing would ever be the same. I was moved emotionally and new this was a new pivotal moment.

As to compromises in a small two way. There is no getting around it. I can give you low end extension if you don't mind low SPL levels. The real limiting factor is SPL in lower ranges because it all comes back to moving enough air.

One way around it is to do what AJ did and add a small powered woofer to it. You can see a pic of it in his profile pic. This also removes low frequency duty from the mid-bass driver. And any time you limit the exertion duties imposed on the small woofer then it can do everything else more easily and more clearly. And you are taking away a very important and overlooked aspect that is the stored energy that a driver has to get rid of that is imposed by those long movements.

[Vapor Audio]

Hey guys, I gave Danny a call earlier to make sure it was cool that I jump in here.  Obviously I have plenty I can add to the conversation, just wanto to make sure I wouldn't step on any toes. 

There really is so much I could say that I don't know where to begin.  I try to build as 'ultimate' as I can, but still there's things I could do to make the cabinets even better.  I've done a lot of work with material research and testing to find what I think will work best.  From all the testing and research I've done, you want the highest possible tensile strength AND internal damping.  Baltic Birch is good because it is very high in both regards.  Metals like aluminum are higher in tensile strength, but have 0 internal damping.  With an accelerometer you absolutely can measure ringing in a cabinet.  My last CNC cut stone as his primary line of work, so I had me make me baffles out of Granite, Marble, Onyx, and some cast stone material he had.  They were just slabs of material with no driver cutouts, and for testing I mounted one of those NXT drivers to them and an accelerometer at the far end of the slab.  Granite in my informal testing was worst, transmissing as much vibration from one end of the slab to the other, marble was best.  To keep things short I'll save my speculation why that is, but I think I know. 

There is an ultimate material if you ask me, Phenolics ... or potentially another type of thermoplastic.  I do have a couple specifically in mind, there are literally hundreds of all different composition and intented purpose.  For just a taste, take a look at this:

http://norplex-micarta.com/products/product-detail.php?page=30

I've spent hours and hours reading through spec sheets on thermoplastics and have found a couple that I believe are the ideal combination of tensile strength and internal damping.  The problem is they're difficult to machine, VERY expensive, and VERY heavy.  A Cirrus cabinet made from one I have in mind would probably cost $3000 in materials alone per pair, another $1000-$2000 of machine time, and then assembly is another issue because most take very specific adhesives in order to glue together ... if they can be glued together at all.  And applying a finish would be no simple matter due to inability to sand the finished cabinet.  But for $10K I'd be willing to take the project on 

That's just materials.  Shape of the cabinet matters too of course.  CNC allows me to integrate the 3" roundover into my cabinets, it lets me shape the internals like the Finite Element Analysis said I should to minimize back wave reflection through the woofer cone, and it lets me do other tricks like the groove cut into the walls that I will with my 'secret sauce'. 

All I see people talk about is resonances in cabinets.  You must also consider that sound has no problem passing through materials, so sound transmission through the walls must also be considered.  It's a bigger deal that you might realize.  I tested by burying a mic capsule in the outer wall of a cabinet and cover it with a huge mound of putty.  What I do to address it is kinda one of my little secrets so I really don't want to lay it all out, but consider this - speed of sound changes with medium change, and every time speed of sound changes, some energy is scrubbed off as heat.  So the goal is to make sound pass through as may differential materials as possible in it's path through a cabinet wall. 

All of this, and we've only been talking about cabinet design.  I need a break now!

[WGH]

I agree, Phenolics can transform an average cabinet into something bordering on the high end but building a good looking speaker cabinet with this stuff would try anybody's patience. My experiments exceeded my expectations.

Read more here:
http://www.audiocircle.com/index.php?topic=72808.0

And here:
http://www.audiocircle.com/index.php?topic=92198.0



Wayne

[EthanH]

Very interesting discussion; it's a real treat to hear the ideas of manufacturers on this topic.  I would assume that it would be easier to make a "dead" cabinet for a monitor than a two-way floorstander, as the cabinet would be more compact and rigid (which may contribute to monitors doing what they do best, i.e., imaging, "disappearing," etc.).

One thing I'm curious about is whether the opposing woofer technique you see with some subwoofers actually works in canceling out vibrations, and, if so, how well.  I'm sure Danny could probably answer this considering his experience using Rythmik subs. I ask because the discussion of enclosure resonances and what not made me think of the barefoot sound approach:

http://www.barefootsound.com/products_mm27.html

Never heard them but they seem like an interesting approach to getting big sound out of a small cabinet.  Doing a similar thing but semi-active might be interesting, but I assume you still wouldn't get truly "big driver" sound like you would from, say, the big GR OB.

[aron944]

"From all the testing and research I've done, you want the highest possible tensile strength AND internal damping" So is there any truth to the claim by Magico that an over-damped cabinet is one that removes resolution to bass detail or is just about balancing the different attributes? http://magico.net/Technology/Enclosures/Enclosures_02.php While we are at it is there a concise definition of "damped" available as it relates to speaker building? Lastly, where does open baffle fall in the "damped" category?

[Ric Schultz]

I just posted this info on the baffle forum but since we are here and now.....here goes.  To follow up on what Danny was saying.....you will never get the low distortion sound of an open baffle from a box.  The air pressure behind the driver limits its ability to track small variations in signal.  This I have heard directly.  Also a two way speaker is always compromised.  The woofer is modulating the midrange and also the back EMF from the woofer excursions also screws with both the mids and highs.  Also you can never get great bass from a small box.  And, if you biamp you can use equalization on the woof and remove the back emf all together from the mids and highs.  Have you ever heard bass in your room equalized to plus and minus 1db?  So, what is the purpose of a monitor?  They look cute.  If you have very little money then they make sense.  But why would you want to spend serious money on an expensive 2 way monitor when something like what Danny will be making shortly will simply kill any monitor.  3 servo 8s with open baffle mids and tweet above?  You are not going to touch this with a tiny squeeky boxey two way...no way.  The footprint of an open baffle system can be as little as 10 inches wide.  So, basically the same as a monitor on a stand.  If you do not like the mids radiating to the rear you can simply hang some felt on the back of the speaker. 

[saisunil]

But why would you want to spend serious money on an expensive 2 way monitor when something like what Danny will be making shortly will simply kill any monitor.  3 servo 8s with open baffle mids and tweet above?

Danny, you are kill'n me ...

[Jonathon Janusz]

Cool that this thread took off.

I just read through to get up to date, and I don't have a lot of time to quote/paste, so just a few things off the top of my head:

Small floorstanders count?  The argument was made that this was the "worst case scenario".  As example, I refer to the X-SLS Danny posted earlier.  If I remember right, Danny had mentioned that the original X-LS (monitor version) speaker was a compromise design for the woofer in that the internal cabinet volume was workable but too small ideally.  The X-SLS (same speaker in all other regards) allowed the speaker to be made with the ideal internal volume for the driver (about a third of the cabinet or so is just dead/empty air space sealed from the speaker cavity, with a neat plug to sand/shot fill the space) so, in effect, the speaker is really just a "best case scenario" cabinet design for THAT speaker design (in effect , making a "weird" looking tallish monitor speaker).  Taken in context of that (basically building the cabinet to whatever be the "ideal" volume for the drivers used) making a final speaker roughly the size of the average comparable monitor, sure, small floorstanders can count. 

Only exception I might make to throw certain ones out would be if the cabinet were to integrate some sort of independent bass module as an integral and not optional part of the design (SP Tech gets a pass because theirs is really just a volume extension for the drivers built as part of the monitor, the monitor can stand/function just fine on its own).  I see it as kind of "cheating" in regards to the theoretical design/discussion at hand.  AJ found a way around it while keeping the traditional form factor, as did TAD with a coaxial (sneaking a third driver into two drivers worth of space).

Regarding cabinet materials and such.  The idea was asked regarding using MDF in place of wood or some of the other exotics and calling that acceptable. PBN uses a combination of MDF, solid wood baffles, and veneer and premium finishes (and I don't think anyone would argue them not high-end), so sure, I think MDF should count, but it seems by looking around that those that do use MDF really put a lot of engineering/finishing/design time and dollars into making it look like anything but an MDF box, so that should be kept in mind.  Considering its machinability, picture for a moment the idea of starting with a solid block of MDF of appropriate size and a huge 4 or 5 axis CNC to cut the whole mess out of one contiguous piece of material - no joints, no glue, no fasteners other than what would hold the electronic components in. . .

Also, on the topic of plastics, the generations of the Gedlee Abbeys (and other designs in the family) prove that one out as good.

On open baffles as a consideration, not exactly exotic "high end", but the Eminent Technology LFT-16 are a monitor design with both OB design elements as well as uniquely engineered cabinet geometry in providing both stylistic form as well as performance in regards to the enclosed woofer.  Granted, in terms of this discussion, they fall flat probably in the areas of crossover/wiring components as well as external fit and finish.  My point being nothing more than this example proves that open baffle can't be completely counted out.  I know it breaks the rule of "one woofer, one tweeter", but if we are going that way, the TADs are out too (coaxial plus woofer).

Regarding stacked MDF vs. stacked birch.  Unfortunately, the road to my little personal experiment is quickly coming to an end regarding being able to test out the stacked birch part of the argument, but I can tell you from experience that my stacked laminated MDF cabinets work.  Being (brutally) honest, final fit and finish could have gone better, had I made a few different choices during construction to be called "high end", but they are in fact solid as rocks, and if I remember right using MDF rather than baltic birch (both in materials cost and finishing cost) cut the total cost of production in half or better for my project (I refer to my sealed cabinet build based on the Super-V).

I've got more, but I really have to get some sleep.

[Jonathon Janusz]

Ric, I just saw your reply (I was typing up my last one).

Respectfully, although you may very well be (arguably) right on all counts, for the purposes of this discussion, "why one would want this" doesn't really matter.  Suffice to say, there are people that want it, companies that design/build/market/sell to it, and money enough changing hands to prove - right or wrong, good or bad, "the best" or something less - that the discussion of the concept is very relevant in the reality in which we live.

The two-way boxed mini-monitor may not be the most perfect baby in the bath, but lets not send the baby out with the water, but rather concentrate on figuring out exactly what makes this baby - imperfections and all - beautiful all the same.

In my mind, in this case, part of the appeal or charm in the thing is marveling at the nuts and bolts of what goes in to making something truly special in spite of all of the compromises suggested above.

Cheers and good night!

[AJinFLA]

Speaking of the TAD Speakers. They make the best sounding stand mounted speakers that I have heard at a show.

Didn't realize you got to hear those. Andy was my next door neighbor at RMAF and we got a chance to converse a bit (Brit on my moms side of family). I agree with you. Superb sound, nothing sticks out, no problems...excellent chance it will stick with you long term. I would sure hope so for the price! I would give it a leg up on the Magico, which left me a bit underwhelmed (take it with a grain of salt, I am not immunized against bias ).
Had him beat in the bass, but the upper end of the TADs were very transparent. I offered a bribe for a couple of those drivers....

cheers,

AJ

[Vapor Audio]

One thing I'm curious about is whether the opposing woofer technique you see with some subwoofers actually works in canceling out vibrations, and, if so, how well.  I'm sure Danny could probably answer this considering his experience using Rythmik subs. I ask because the discussion of enclosure resonances and what not made me think of the barefoot sound approach:

http://www.barefootsound.com/products_mm27.html

Never heard them but they seem like an interesting approach to getting big sound out of a small cabinet.  Doing a similar thing but semi-active might be interesting, but I assume you still wouldn't get truly "big driver" sound like you would from, say, the big GR OB.

Typically when we talk about opposing woofers canceling anything it's in regard to odd order distortion harmonics ... notcabinet resonances.  But with how they're doing it, with the two drivers coupled together into one opposing unit, I can see how it would reduce energy put into the cabinet.  Reduce, but of course not eliminate.  When talking about 10" subs there's a LOT of vibrational energy being created, motors like that can generate in the range of 2hp.  Coupling the drivers will help, but all that energy doesn't just disappear, a lot is still going to go into the cabinet as vibrations.