Jump to content

AR MGC-1


der
 Share

Recommended Posts

I just read a reprinted article about the AR MGC-1 speaker from 1985 on the Stereophile website. I was pretty busy back in those days with the family I guess because I've never heard of them until today. An interesting read. I can now add them along with the LST to my list of AR speakers I've not heard but would like to.

Anyone own a pair?

der

Link to comment
Share on other sites

You should also seek out the Stereo Review and High Fidelity reviews of this speaker. It really made quite an impact on the audio press, although the actual sales were miniscule.

It certainly was an innovative and ambitious design. Due to the very precise reflecting angles involved, the speaker was really best suited to conventionally-shaped rectangular rooms.

By far the most controversial aspect of its design was the marketing decision to use dual 8-inch woofers and take the bass response down to only around 39-40 Hz. Just a tad deeper than the 2ax-5-12 level, but not as deep as the 3a-LST-11 level. Defenders of the MGC-1’s bass are quick to point of that the difference between the Magic’s 39 Hz and the 3a’s 35 Hz is minor, hardly worth quibbling about.

In reality, the bass was in two different worlds. For an AR loudspeaker, there are two kinds of bass and only two kinds of bass: AR 12-inch bass and AR less-than-12-inch bass. The MGC-1 was not AR 12-inch bass.

I was at the Boston Audio Society meeting where the MGC-1 was introduced and demo’d and I heard it several more times at a BAS member’s house. It was a superbly clean and detailed speaker and its side-firing array with delay amp did a pretty good job of creating a nice three-dimensional illusion.

But the BAS and local audio press was merciless in their criticism of AR for their choice not to give the MGC-1 at least 3a-level bass. Especially considering the MGC-1’s price: $3500/sys. in walnut and $7000/sys. in genuine rosewood. Stratospheric pricing in the mid-80’s. Merciless.

To the point where AR was compelled to come out with an MGC-2! This was a conventional tower speaker in a rectangular cross-section cabinet with a diagonal gold inlaid stripe on the top panel. The user was to align the gold stripe to be parallel with the wall behind the speaker and that would orient the MGC-2 at the correct angle for the side-firing array to work correctly. But the main thing about the -2 was that it used a 12-inch woofer and had bass fully equivalent to any other AR 12-inch speaker. I remember Ron Fone—AR’s president at the time—saying to the BAS at a later meeting, “AR had finally gotten it right this time.”

I don’t know for certain if the MGC-2 ever went into production and if any were ever sold. But I have a nice brochure on them—probably the only one in existence!

Steve F.

Link to comment
Share on other sites

Thanks for the great information Steve! I'll check out the other reviews you mentioned. I was curious as to why they went with 8" woofers given what they were asking for them. I've owned a pair of AR 4x along with my AR3a for 40 years and you're exactly right - there's AR 8 bass and AR 12 bass.

der

Link to comment
Share on other sites

Ken Kantor designed this. He didn't come right out and say it, but my impression talking to him about it was that TPTB at AR decided that a 12" woofer would have given the MGC-1 TOTL status instead of the company's then current flagship model (which, I think, would have been the AR9LS).

The MGC-2 was allowed the 12" woofer, but whether it was a last ditch effort to make an MGC they could sell or there was some other reason, Ken didn't seem to have any thoughts.

I think that today multi-channel amps and surround speaker arrays have taken ownership of what the MGCs were originally intended to do, but if I could get my hands on a pair, I'd be talking to Ken for advice on how to retrofit them with 12" woofers and bypass the original delayed-signal circuits for the side-firing drivers.

Link to comment
Share on other sites

Steve -


I seem to recall reading that the MGC-2 woofer used a polypropylene cone - does your brochure agree with this?




Yes, it was a pp woofer. All their woofers at that point were pp. The TOTL line at that time was transitioning from the 9LS to the TSW910. The 910 definitely had pp woofs. Also at that time, the more high-end Connoisseur Series was concurrent with the MGC-1 and the TSWs. I had Conni 50t's (12" woof, 6" cone mid, 1" titanium tweeter) and the woofer and mid were pp. The 50's were nice speakers, but a bit bright. And even though the cabinet volume was around 2 cu ft compared to the 11/3a's 1.48 cu ft, the 50 definitely did not go deeper--if even as deep. Gives a lot of credence to the thought that those Japanese Tonegen pp woofers had a meaningfully higher Fs than the paper cone 12" woofers that had been built by AR in MA.


If I get motivated, I'll scan and post the MGC-2 lit.


Steve F.

Link to comment
Share on other sites

Here is the MGC lit. I scanned it in color, 4 pages. Gene or another Admin should add this to the Library.

The sharp-eyed will notice:

1. AR spec'd the 12" MGC-2 at -3dB @ 39Hz, the same as the MGC-1's dual 8-inchers, to avoid embarrassing the -1. The -1 had barely 2ax-level bass in real life (remember, I heard them many times), while the -2 had normal AR 12-inch bass. All Classic and ADD AR 12-inchers were 35 Hz.

2. The -1 had a 9LS-era dual-dome assembly, with a 3/4" soft-dome tweeter. The -2 had a 1" titanium dome, a la the Connoisseur 50t.

3. The -1 had a 2-way side array with a 1" dome tweeter, probably a soft dome, same as their better 2-way offerings of that era.

4. The -2 had a single 6 1/2-inch full-range side driver--no tweeter. Note that the side array on both models was electronically limited to 5,000 Hz anyway.

On the plus side, these were really seriously-engineered speakers of the highest quality, with a very ambitious goal. On the minus side, they didn't sell at all and they didn't confer any meaningful market attention onto AR that helped the sales of their "regular" speakers.

Steve F.

post-100522-0-88830800-1442771822_thumb.

post-100522-0-46785600-1442771831_thumb.

post-100522-0-15140200-1442771840_thumb.

post-100522-0-58255100-1442771849_thumb.

Link to comment
Share on other sites

Kantor's article in Audio from his site in .pdf:

http://www.kenkantor.com/publications/magic_speaker/magic_speaker.pdf

He also had an AES article on the subject:

A Psychoacoustically Optimized Loudspeaker, JAES

https://secure.aes.org/forum/pubs/journal/?elib=5230

Link to comment
Share on other sites

In terms of being “worth looking at,” there are several considerations.

First, and most important from a practical standpoint, is that the foam inserts that control the speakers’ directivity may have all degraded into nothingness by today, 30 years after they were made. Unlike merely re-foaming a woofer surround, it may well be impossible to replace/re-create these inserts. Without them, the original performance of the speakers will be lost.

Second, you’d have to determine that the associated ambient amplifier was working and in proper condition. I doubt you could find a service schematic for such a rare item and without one, you’d have to find a technician who could recognize by sight what the circuitry and layout were all about, and then test for leaky capacitors, etc.

Third, the very design premise of the speakers—wider soundstage and a more ambient sound akin to the original performance venue—has been rendered irrelevant. Not that the final goal is irrelevant, but modern multi-channel digital/home theater electronics very strongly suggest that the best way to accomplish this goal is with sophisticated receivers and pre-amp/processors, feeding multiple speakers around the room. There are better, more convincing ways to do this today than there was 30 years ago. I suppose the best thing that the Magics had going for them was the ability to sound three-dimensionally lifelike using only two speakers, as opposed to a modern multi-channel system requiring 5 or 7 speakers.

For all these reasons—especially the first—I’d be very cautious. If you can find them for next to nothing, then why not, but I wouldn’t expend too much time, energy or money chasing them down.

Steve F.

Link to comment
Share on other sites

  • 4 years later...

I'm not sure if I've ever seen the XO schematic.

You might ask Ken Kantor, or some of the experts on here.  Please post it if you

find it.

Link to comment
Share on other sites

12 hours ago, Pete B said:

I'm not sure if I've ever seen the XO schematic.

You might ask Ken Kantor, or some of the experts on here.  Please post it if you

find it.

Unfortunately, I've read comments from Ken, where he no longer has crossover schematics either.  So, unobaitium, at this point, short of an MGC-1 owner tracing out the wiring?

Link to comment
Share on other sites

The MGC-2 has a 12" woofer and 6" lower mid!

Do you know if the 4" mid was the same Peerless (KO40MRF) driver used in the MGC-1?

https://reconingspeakers.com/2011/11/07/peerless-k040-mrf-midrange-repair/

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...