[josh358]

Excellent post(s) Josh!   I had to ponder the statement that tube amps have more power reserve than SS amps.  At first, I questioned it, but I think I understand your point now.   Certainly tube amps do not clip the same way and measuring their max power, i.e. clip point typically has to be done at some objective level, when in fact they don't really objectively have a level in which they "clip".   So yeah, they have more power on reserve, just at a raised THD level.  A sort of compression like effect.

Exactly. Power measurements are generally taken at a specified THD level and tubes clip more gradually beyond that, giving them more usable headroom for a given RMS power rating.

[josh358]

You remember Bob Carver's launch of Sunfire with the subwoofer - world's most powerful subwoofer or something like that out of a small enclosure.  It created headlines and launched a successful company.
Before that, when he was invited to leave Phase Linear he launched the Carver Corp. by making a 100 WPC amp in a Folger's coffee can.  Big numbers in small packages are very impressive and garner the headlines and the investment capital.
A lot of it seems kind of silly but that's what sells.

A high end manufacturer told me once that the fancy panel accounts for more than half the cost of his power amplifiers. They tried making a bare bones version with the same circuit and a more utilitarian panel, and nobody bought it!

[josh358]

Emsquare(d)? Ow... Josh, buddy. I vaguely regret using that moniker. I had to call myself something though. That's OK. Still enjoy reading your thoughts as I pick out some nuggets of knowledge when I recognize them. Hope your holidays were particularly good to you.

Signing off now. I have a date with the new Regina Spektor stuff I recently acquired. And a bottle of Bushmills single malt, 10 year. Wheee ...

"On the radio, uh oh"

Ouch! Haven't gotten a name so wrong since Hemholtz, but that at least was understandable (and I'm not the only one to think he was "Helmholtz" either).

[medium jim]

Ouch! Haven't gotten a name so wrong since Hemholtz, but that at least was understandable (and I'm not the only one to think he was "Helmholtz" either).

+1 LOL

Jim

[SteveFord]

Funny you should mention the fancy panels. 
Earlier today I was flipping through some recent issues of TAS and one Jeff Rowland device caught my eye.  I wondered just how much time and money went into manufacturing small lots of those sculpted faceplates?  A lot, I would think.
Frank Van Alstine finally started getting some real favorable press when he spruced up his faceplates a bit. 
Good for him and it shows how much our perception of value or worth is based on cosmetics.
Many years ago I owned a powder coating shop and Rogue Audio was just a few miles away.  They were launching a new line and were going to introduce it at some show.
They had me do the powder coating and needed something really distinctive to draw attention to their product.  Anyone who owns a mid 90s Rogue Audio component, I chose Morton Tuxedo Black powder.  The trade show pieces were very handsome; I was too expensive for them to use for the production pieces but I'm sure that they were fine.
Enough of Memory Lane.

[josh358]

Funny you should mention the fancy panels. 
Earlier today I was flipping through some recent issues of TAS and one Jeff Rowland device caught my eye.  I wondered just how much time and money went into manufacturing small lots of those sculpted faceplates?  A lot, I would think.
Frank Van Alstine finally started getting some real favorable press when he spruced up his faceplates a bit. 
Good for him and it shows how much our perception of value or worth is based on cosmetics.
Many years ago I owned a powder coating shop and Rogue Audio was just a few miles away.  They were launching a new line and were going to introduce it at some show.
They had me do the powder coating and needed something really distinctive to draw attention to their product.  Anyone who owns a mid 90s Rogue Audio component, I chose Morton Tuxedo Black powder.  The trade show pieces were very handsome; I was too expensive for them to use for the production pieces but I'm sure that they were fine.
Enough of Memory Lane.

When we built custom gear, we used to take brushed aluminum panels and have them black anodized, then engrave and white fill the legends. I've loved that look since I saw my first Moog synthesizer (which however was silk screened). I still have a keyboard controller panel somewhere that I managed to dent and had to replace -- I should send it to the friend who lent me his Moog.

[kevin360]

I, too, would like to see Dave's comparative response measurements. The fact that the speakers were only quasi-gunned is insignificant to that metric. Of immeasurably greater importance is the proper context of the measurement procedure. To my knowledge, the results were never posted – all that I recall seeing on the PA is the modeled electrical response.

On the topic of power requirements, I agree with Josh – context is everything. In my current situation with my MMG/REL hybrids, a meager 100wpc (200 into 4 ohms) solid state, integrated amp is more than sufficient – enough to run me out of my chair if I crank it. I have no doubt that I could get away with less. I also must say that there's 'magic' in such close proximity to the subs – the room seems effectively out of the equation.

Speaking of equations, Josh, I think that's how you added the 'd' to emsquare's moniker. You were thinking of a formula (well, it's somewhat close to e=mc^2), whereas the etymology of his chosen representation is a form of representation itself – the typeface (specifically one with which the 'e' and 'm' are square). I read Hemholtz as Helmholtz for at least a year – our brains apply rules to that which we perceive without our consent (and Helmholtz was so familiar that I saw an 'l' that wasn't there).

I love the story of how Rick Wakeman acquired his first Moog. A wealthy actor thought his was defective because it only played one note at a time, so he let it go fairly cheap. Obviously, that's not the whole story (or even much of a synopsis), but I don't have Rick's talent for story telling (he's brilliant at it, BTW).

[SteveFord]

If all goes according to plan MGBert is going to swing by with his Magnestands so we'll be able to compare them to the regular old MMGs and the 1.7s. 
I've never heard the Magnestands and he's never heard the 1.7s so it should be fun.   
We'll write up a review of sorts.  Look for it sometime in early 2013.

[Davey]

Kevin,

I'm not going to post any of my measurements of quasi-gunned MMG's.  The reason is a somewhat interesting/entertaining story that dates back a few years....which I've related part of to Steve via PM. 
If folks who own the speakers are happy with them, excellent.  If a few of those folks are interested in taking some measurements of their speakers, by all means do so.  I've outlined a basic setup that might be used.

I may revisit my own MMG/dipole-woofer system in a few months to update with larger woofers.  That, I will post measurements/photo's of.
I'm busy with non-Magneplanar projects currently so don't have any timetable.

Cheers,

Dave.

[kevin360]

Dave, I understand completely - no need to explain. I agree with the live and let live concept, as well as the notion that there are plenty of different 'sounds' to find pleasing.

I definitely look forward to the posts on your new dipole sub project. Best of luck with your other project(s) - always something in the fire.

[josh358]

I, too, would like to see Dave's comparative response measurements. The fact that the speakers were only quasi-gunned is insignificant to that metric. Of immeasurably greater importance is the proper context of the measurement procedure. To my knowledge, the results were never posted – all that I recall seeing on the PA is the modeled electrical response.

On the topic of power requirements, I agree with Josh – context is everything. In my current situation with my MMG/REL hybrids, a meager 100wpc (200 into 4 ohms) solid state, integrated amp is more than sufficient – enough to run me out of my chair if I crank it. I have no doubt that I could get away with less. I also must say that there's 'magic' in such close proximity to the subs – the room seems effectively out of the equation.

Speaking of equations, Josh, I think that's how you added the 'd' to emsquare's moniker. You were thinking of a formula (well, it's somewhat close to e=mc^2), whereas the etymology of his chosen representation is a form of representation itself – the typeface (specifically one with which the 'e' and 'm' are square). I read Hemholtz as Helmholtz for at least a year – our brains apply rules to that which we perceive without our consent (and Helmholtz was so familiar that I saw an 'l' that wasn't there).

I love the story of how Rick Wakeman acquired his first Moog. A wealthy actor thought his was defective because it only played one note at a time, so he let it go fairly cheap. Obviously, that's not the whole story (or even much of a synopsis), but I don't have Rick's talent for story telling (he's brilliant at it, BTW).

Love that story about the Moog.

I was definitely thinking of M^2. It's been shown that we don't actually read most of the letters in a word, just grasp the overall shape. I had to learn to see each letter when I learned to proofread in high school -- the printing teacher taught me to move a pencil along the line to force my eyes to check every one. But by the same token, a high school printing buff like me (actually got to be a pretty good Linotypist) should have thought of an EM space!

Dave did some measurements of the radiation pattern of the MMG and found it behaved more like a line source than a point source, so listening in the near field should really slash your power requirements. Paradoxically, this should mean that it needs *more* power at a normal listening distance than its bigger brothers. However, I've found that it starts to suffer from IM distortion at higher levels, so never had an inclination to push the levels. That of course would be less llikely to happen in the near field, plus when I've tried moving closer than five feet or so I noticed a huge proximity boost in the bass. Those planar woofers really put out a tremendous amount of bass since they have to compensate for the 6 dB/octave dipole cancellation below Fequal.

BTW, there's an article on modern models of sensory integration in the new Scientific American. Thought of you when I saw it. It seems they've become much more sophisticated in their understanding of the degree to which specialized regions in the brain cooperatively influence one another, e.g., the visual cortex can give rise to activity in the auditory cortex, etc.

[josh358]

If all goes according to plan MGBert is going to swing by with his Magnestands so we'll be able to compare them to the regular old MMGs and the 1.7s. 
I've never heard the Magnestands and he's never heard the 1.7s so it should be fun.   
We'll write up a review of sorts.  Look for it sometime in early 2013.

Hope you'll take some measurements! Mostly out of curiosity, but also because this comes up perennially -- are the gunned Maggies really more efficient, do they extend the bass, what does the new crossover do to the midrange response, etc. (JBen has already posted comparative measurements of the pole-piece-in-front configuration, though I think they're taken from one point, when in theory the upper octave response should vary owing to the pole piece hole spacing being large compared to wavelength.)

[Emsquare]

Ouch! Haven't gotten a name so wrong since Hemholtz, but that at least was understandable (and I'm not the only one to think he was "Helmholtz" either).

It's 'no thing'. I just thought it was kinda funny so I thought I would play into the joke. As is my custom. Happy New Year to you.

[josh358]

It's 'no thing'. I just thought it was kinda funny so I thought I would play into the joke. As is my custom. Happy New Year to you.

And to you as well, squared!