[rollo]

Hey Steve, amazing news!

I see several have already mentioned HP's room 2. I asked Wendell about that a few days ago and he said Maggies have always done well in that room, even Tympanis. We were speculating as Rollo did that the angled corners had something to do with that. It seems to me, looking from the picture, that they would delay the sound that would ordinarily be the troublesome corner second reflection. This is what makes the sound from dipoles wrap around the walls in a small room. The angled corners would work like the angled facets that are used to make a reflection-free zone in a studio control room, delaying early reflections by at least 5 ms, preferably more, because the ear uses them to judge the size of an acoustical space, and because early reflections can cause positional shift and coloration.

Here's the photo of Listening Room 2, it should warm the hearts of all of us crazy enough to put large Maggies in small rooms:

http://www.hpsoundings.com/2012/12/1170/

Though not necessarily wives who grow suspicious when they see us in the living room corner with sheetrock and nails . . .

   Good point about the angled walls. Also lots of wood trim to diffuse the sound. Another factor is the length of the room. Really a rectangle of good proportion. Somewhere in one of the older Absolute sound issues are the dimensions of HPs room.

charles

[jhm731]

HP's Music Room 2:

[kevin360]

Really a rectangle of good proportion

If the ceiling is 8', it's actually a rectangle of horrific proportions - 16x12x8 yields lots of common modes. It's a good thing that 4'4" extension to the doorway exists on the one side of the rear of the room. I'd imagine the beveled corners up front help a bit too.

BTW, I'd take Rm 1 any day - love those Scaenas!


---edit---

Okay, I was in error; it's room 3. My only real point is that I'd love to have that Scaena 1.4 speaker system in my room!

[jhm731]

If the ceiling is 8', it's actually a rectangle of horrific proportions - 16x12x8 yields lots of common modes. It's a good thing that 4'4" extension to the doorway exists on the one side of the rear of the room. I'd imagine the beveled corners up front help a bit too.

BTW, I'd take Rm 1 any day - love those Scaenas!

Scaenas are in Room 3:
http://www.hpsoundings.com/2012/11/reference-system-report-room-3-2/

[josh358]

If the ceiling is 8', it's actually a rectangle of horrific proportions - 16x12x8 yields lots of common modes. It's a good thing that 4'4" extension to the doorway exists on the one side of the rear of the room. I'd imagine the beveled corners up front help a bit too.

BTW, I'd take Rm 1 any day - love those Scaenas!

Fortunately, line sources don't excite the vertical modes. The length modes are most of the problem, at least if the speakers are parallel to the front wall. As they're toed in, the width modes are also excited, but HP's pair looks like it isn't toed in very much -- the length of the room would help with that.

Another thing about Maggies -- I did a rough calculation based on eyeballing the 29" 20.7's in the photo and with the mono bass of an LP, I figure you'll get a pretty good plane wave up to roughly 66 Hz with HP's setup. The cool thing about that is that if you sit at the same distance from the rear wall as the speakers are from the front and the room is rectangular, line source dipoles will cancel *all* the room modes up to about that frequency (half of the spatial Nyquist frequency which is determined by the spacing of the speakers and their reflected side wall images). I can't tell for sure but it looks from the sketch as if that's very roughly true in HP's room. I discovered this effect years ago with my 1-D's although back then I didn't entirely understand the physics of it, it wasn't until I read about single and double bass arrays that I realized that the reflected images were joining with the physical speakers to create a plane wave. The plane wave cancels all except the vertical length mode and then the reflected back wave chases the front wave cancelling the reflected front wave at the listener's ears.

[josh358]

   Good point about the angled walls. Also lots of wood trim to diffuse the sound. Another factor is the length of the room. Really a rectangle of good proportion. Somewhere in one of the older Absolute sound issues are the dimensions of HPs room.

charles

It looks like you used a bit of HF absorption in the form of those curtains and the carpet too?

Do you know how far the 20.7's are from the front wall?

[josh358]

HP's Music Room 2:

Thanks for posting that, we were speculating on the rest of the room on the Planar Asylum.

[SteveFord]

Berni,
Could you email the drawings for those stands you made?  I think that may be a good idea and I can incorporate it into the oval bases that Magnepan supplies.
I did a little rearranging today and finished getting the dog hair off of the throw rugs and coffee table cover so I could put the room back together and yeah, these will work where the 3.7s will.
5' out from the windows, drapes drawn, much closer to the side walls and a slight toe in will do it.
I spoke w/ Wendell today and he asked what I thought and I told him that I think I understand what one fellow meant when he said all of the Magnepans since the Tympanis sounded "thin".
There's a real heft or weight to the sound that is different from the other models; I'm sure that I'm not saying it right but there's power to these speakers.
If you've ever been behind the wheel of a really fast car, been on a very fast motorcycle or attended a professional drag race you'll know what I mean - even at idle you can just tell what they're capable of.
Right now they're idleing as the women folk are home - don't they ever go anywhere?  How inconsiderate can some people be?  I've gotta crank the volume up and break these suckers in.
Some people.  Shouldn't they be shopping or something?

I asked about the construction and was told that the tweeter section is the same as the 3.7s but everything else is different; that accounts for the same basic sonic signature along with the difference I'm hearing.

[Davey]

Scaenas are in Room 3:
http://www.hpsoundings.com/2012/11/reference-system-report-room-3-2/

What a horrendous looking listening room. 
And room number 2 is a closet. 
How can anybody evaluate anything in that type of environment?

Cheers,

Dave.

[jhm731]

oval bases that Magnepan supplies.

Steve,

Congrats on your new 20.7s.

Didn't know that Magnepan is now supplying an oval base.

How does it attached to the speaker?

[SteveFord]

Like so:



Each bracket has two screws to the speaker, two screws to the base.
The underside of the base is countersunk for the washers and nuts and the base is really slippery so sliding the speakers around is real easy.  I was kind of worried about that part of it but somebody used their noodle.

The white pieces under the rear of the base are some felt pads stuck under there as a temporary way to get them level - the old house has settled some in the past 65 years.

I think that I'll wind up with more bass than I wish but Kara Chafee was good enough to run some calculations for me a few months ago and I can fix that by swapping out two output caps in the preamp.  The audio industry really has a lot of good people in it.

[josh358]

I think that I'll wind up with more bass than I wish but Kara Chafee was good enough to run some calculations for me a few months ago and I can fix that by swapping out two output caps in the preamp.  The audio industry really has a lot of good people in it.

As Wendell points out, a large woofer will make too much bass in a small room, a small woofer too little in a big one. Hence the idea of using the DWM to boost midbass inlarger rooms. Too much bass is a good thing, though, since it's easy to equalize down, and you end up with extra headroom! I think we sometimes take the purist thing to extremes, e.g., the absence of tone controls and the aversion to equalization, which can improve just about any speaker/room combination if done right.

[TONEPUB]

I don't think so...I think just the other way around, the 20.7's were properly set up....well into the room and without room treatment other than carpeting and chairs for listening.

Jim

I think you just like to argue...

I've heard the 20.1s set up with the right subs a number of times, so I know it can be done properly.  Just like the ML CLX, it's tough to get right.

[MGbert]

As Wendell points out, a large woofer will make too much bass in a small room, a small woofer too little in a big one. Hence the idea of using the DWM to boost midbass inlarger rooms. Too much bass is a good thing, though, since it's easy to equalize down, and you end up with extra headroom! I think we sometimes take the purist thing to extremes, e.g., the absence of tone controls and the aversion to equalization, which can improve just about any speaker/room combination if done right.

At the risk of being labeled "one of those", I second Josh's endorsement of EQ.  At least the Behringer DEQ2496, which does everything in the digital regime.  Even if you leave everything above 200 Hz alone, the ability to smooth out bass response in the room is well worth the price of admission.

Off topic, but one "hidden" ability of the DEQ is the stereo width control.  It lets you go between standard stereo to mono in 10 steps, and I find that listening to orchestral works with the control set at 2 or 3 (in other words, almost mono but not quite) gives an uncanny sense of listening close to the rear of the hall, which can be more realistic than standard stereo - at least in my space.

MGbert

[roscoeiii]

If you are going to think EQ, I highly recommend the DSPeaker Dual Core 2.0. DSP below 500Hz, in addition to full spectrum DEQ capabilities, and much else. A few places online, like Tweek Geek that have audition/return policies, so you can try it and decide for yourself. A very, very cool device.

[mg3720]

Congratulations Steve!  You beat me to the punch.  I’ve had my 20.7’s for several months now, but have not had the courage to show them here.  I have them in my theater with other Maggies as surrounds and center (Tri-Center of course).  I have two JL F112 subs, but I have been running the 20.7’s full range.

[medium jim]

I think you just like to argue...

I've heard the 20.1s set up with the right subs a number of times, so I know it can be done properly.  Just like the ML CLX, it's tough to get right.

Let's keep this cordial.  I've heard the 20.1's extensively with the F112's and you are correct about that set up, however, the 20.7's have more authority below 40hz and create enough room energy to satisfy me.  Not major slam, just pure, accurate and amazingly fast bass.

Put it this way, I was semi blown away by them. I sure that when you get a chance to audition a pair you will understand what my ears told me. More to the point, I started a thread on the Bass Circle that named the 20.7 as a stand alone full range speaker about 2 weeks ago after hearing them.

Jim

[jhm731]

Steve,

Mahalo for the info on the new oval bases.

It seems that the brackets would allow one to build some custom
bases to increase stability and/or enhanse the appearance.

[berni]

Steve, no problem, just send me your email adress on PM, you will get all the drawings, they are just in metric measurement.
Happy if you can use them.
I think you could incorporate them without making any changes to the look from the front of the new20.7. Just use the side two bracings and attached them to the board on the floor.
Even easier to make then my design with two feet...

[SteveFord]

I don't have a whole heck of a lot of music that goes really low but last night I put on No Pussyfooting by Fripp and Eno just to see.
At the tail end of the first track the floor should vibrate.
It didn't.
The bass will probably open up a bit more as time goes on but I don't think they'll hit that subsonic region.
I'd need to run line out and set the crossover as low as possible or else it'd muck things up.

Berni,
PM sent, thanks!

mg3720,
We'd better get some more information on that set up!