Opinions sought of Magnepan 20.7

[Ed Presson]

I am considering buying a used Magneplanar 20.7. My brief audition in a
smallish room didn't provide
the wide sound stage that reviews describe. I read that they need lots of
power. I have Bryston 4B amps
which can deliver, I'm told, lots of current.

I'd appreciate any comments from folks with experience with these, and any
advice you can offer.

Ed Presson

[Peter Wieck]

I keep a vintage pair of MG-IIIs, which are the much older brother of the 20.7, approximately the same size, approximately the same frequency response, approximately the same impedance

Year: 1987
3-Way Combination
TR tweeter : ¼″×57″
midrange : 170in²
woofer : 620in²

Frequency Response: 32Hz-40kHz ±3dB

Crossover: EXT: Low-Pass 18dB/octave @ 300Hz
High-Pass 12dB/octave @ 500Hz
INT: 3kHz

75-200Wrms @8Ω

85dB/2.83v/m @500Hz
4Ω

24″ × 71″
130.lbs

Your Bryston amps are ideal high-power amps, which will deliver 500 watts to the 20.7 4Ω load.

Yes, they need space. Presently mine are in a 16' x 27' x 9.5' foot room, which is just adequate for them to shine. A bit wider on the short dimension would be better. These speakers want space and can deliver a very wide, but detailed soundstage. They are incredibly transparent - they truly disappear behind the music they deliver. Their single weakness, if that is what it is, is their frequency response - which seems to have been addressed in the 20.7. I see no downside in that option if you have the room for them. One bit of advice: Throw out the "Speakers must go this way" book, and experiment with placement, Bipolar speakers lend themselves to different options depending on their surroundings. Just try multiple options, you may be pleasantly surprised.

http://www.integracoustics.com/MUG/MUG/articles/speakers.html

Enjoy!

Peter Wieck
Melrose Park, PA

[Ed Presson]

Mr. Wieck,

I tried to reply directly to you, but I missed-directed my reply, so I'll
try again.

Thank you for an informative and helpful replay. I'm especially interested
in your reply that your large room is "just adequate for them to shine." My
new room (actually an artist's studio) will be about 25' x 32' x 9.5' and I
am concerned that the 20.7s might not be able to work well there; that is,
that they many not produce adequate sound levels in such a large room. Your
opinion here would help.

The room in which I heard these Magnepan speakers was smaller than many
bedrooms and the 20.7s did not throw the wide soundstage that expected. It
did render the sections of orchestra music with great fidelity, though. So,
I really did not get a chance to hear them at their best.

Thanks again,
Ed Presson

[Peter Wieck]

My new room (actually an artist's studio) will be about 25' x 32' x 9.5' and I

Post by Ed Presson
am concerned that the 20.7s might not be able to work well there; that is,
that they many not produce adequate sound levels in such a large room. Your
opinion here would help.

I will break a rule given the very nearly perfect (for Maggies) proportions of the room you mention. For a start, put them first on the short wall, about 12 feet apart, very slightly asymmetrically, say, starting at 4 feet from one wall, and 8 feet from the other. Vary that a bit until you like the soundstage. They *might* want to be a bit closer together, but with the Bryston feeding them, likely not.

Put another way, they should be fine in that room. However, it is big enough that they might not like being on the long wall, and certainly not symmetrically on the long wall.

Peter Wieck
Melrose Park, PA