Recycling old designs ???


Several different factors have caused me to start this thread. I'm begining to wonder if we have made ANY progress in audio gear over the last 25 or so years. While that is kind of a rhetorical question ( obviously, we have ), i've run across a whole slew of interesting "already been done" designs recently. On top of that, i also noticed that we had DIGITAL amplifiers as far back as 1975. Has anything REALLY changed ???

How many of you have seen the "new" Mirage "omnipolar" speakers ? They are shown on the inside cover of "Sound & Vision" mag in this months edition. As soon as i saw them, i had to laugh.

The reason that i found them funny is that they are a COMPLETE knock off of what B.I.C. did with their "Soundspan" models TWENTY+ years ago. Only difference is that the Mirages are smaller, wall mountable units whereas the BIC's were all boxed models designed for floor standing use.

Some of you may remember these. They looked VERY much like a set of the old Ohm F's with their grill's on. The similarity did not end there though, as they were trying to mimic the radiation pattern of the F also. The major difference is that they used a three way design to do this whereas the F is a single driver ( point source ) as the radiator.

How the old BIC's and Mirage do this is pretty simple. They place a woofer on the top of a box / speaker cabinet firing straight up. They then suspend the midrange directly above the center of it, kind of like a coaxial design found in many car audio speakers*. This forces the sound from the woofer to "slide out" sideways around the back of the radiused midrange "cabinet", increasing horizontal dispersion. This same approach is used on top of the midrange with the mounting of the tweeter. All speakers are firing directly up but reflecting sideways due to the placement of the driver above it with only the tweeter firing into free space.

What this does is produce 360* of horizontal radiation. The effects of beaming are minimized due to the fact that you have no direct sound radiating towards you. While this does give you a very spacious and diffuse presentation, it can also lack "crispness" or "attack" since all of the sound is heard indirectly. Simply for sake of comparison, the F achieves 360* horizontal radiation BUT also exposes the listener to direct radiation at the same time.

I would think that this approach would work wonderfully for use in a multi-channel HT environment, especially as surrounds. My Brother has told me a million times that i should use the four Ohm F's that i have as mains and surrounds in my HT system for this very reason. Lo and behold, Mirage comes out with this line and it will probably be a success for the "all enveloping" radiation pattern that could literally "surround you in sound". Believe me, it could do this IF done properly.

The question is, was it a design that was WAY ahead of its' time back in the late 1970's or did it need 20+ years worth of refining to make it "right" ??? Is this a product design that lends itself to only HT systems or will it find its' way into audiophile grade 2 channel systems ? Only time will tell.

How many of you have seen products or designs that were "recycled" lately ? It might be interesting to see if we are running around in a big circle and don't even realize it. I'll post some of my other findings later tonight. In the meantime, i hope to see that others have contributed to this thread. I think it will be fun to walk down memory lane and then compare those products to what we have today. Sean
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* Tannoy and a few other manufacturers also make use of coaxial mounted drivers, but for reasons other than what is being discussed here.
sean
How similar are they really other than looks? How about the cabinet materials and internal structure; internal wiring; crossover design; and construction and materials of the driver elements; tweeters, etc, etc??


Some pairs of B&W Series 80 look just like some Matrix 800 Series, but are light years different otherwise.

It does appear that we are recycling old designs.

Sometimes there are only a certain number of ways to achieve a design goal, e.g., 360 degree dispersion. Also, old designs aren't necessarily inferior to modern ones. We all know new designs often give up one quality to gain another, and we don't always agree with the trade-off. You all know as well as I: vinyl-vs-CDs, tubes-vs-solid state, Class A-vs-Class AB, ported woofers-vs-acoustic suspension, direct radiating baffle mounted speakers-vs-horns, etc.

I think its great that manufacturers bring back old designs that were better at some aspect of sound reproduction to provide for a diversity of customer tastes. Hopefully, as time has passed, the industry can improve in its execution on old designs with new materials and design tweaks that reflect insights gleaned over the intervening years (e.g., Avantgarde's horns that preserve many of the advantages of horns while eliminating the characteristic colorations of horns from years ago).

The sonic benefits of broad dispersion are appealing to many people. Some designs like the Ohm Fs are timeless and have essentially remained unequaled over the years. The BICs and Mirages clearly hope(d) to ride on the dispersion bandwagon. Maybe one day we'll see the old Bose 901 resurrected -- they were certainly popular in their day.
Slightly off-topic but gets a good laugh from me are the Subaru ads for the "first sport-utility wagon".

As far as I'm concerned, this claim is complete BS. AMC made their 4wd Eagle in a wagon, all those years ago. Public wasn't ready for the concept at the time however.
Speaker looks change many times for solely cosmetic reasons. A lot of buyers don't want their systems to look like their Dad's. There does seem to be a 70s nostalgia movement in other non-audio areas, so why not. I still use a 70s Kenwood tuner in one system. Why not make a new one? They sure do work better than the new digital ones.
I don't know if you would call it "recycling" old designs as much as I hope taking a new approach to old designs. I really don't think too many should be surprised by some of these design ideas resurgences. You talk about it from the 70's, I had a pair of Stu Hegemanns transmission line enclosures from the 60's just a while back, tweeter mounted coaxially and both woofer and tweeter firing upward, into an aluminum dispersion cone, same basic priciple. We all know tubes are incredibly popular, and vinyl is definitely stronger than it was 20 years ago. Some of it plays to nostalgia, some of it plays to people remembering a design and thinking that with new materials and advances in known sciences that these ideas are due another visit, perhaps working better with these new materials and ideas. I have a current fascination with transmission line enclosures, having just traded for a pair of IMF RSPM's,(the 1st pair of Ohm's were traded Sean) hooked up to an D76a I think its an incredible sounding system. Now I want to upgrade the xver, tighten up the response, change enclosure damping materials, etc. Why would Mirage not be having the same thoughts? At least I hope that s why they are doing it, not for the sake of the ad writers having to have something new to talk about.
Hey Sean, is that you doing a Parabee over at the Bottlehead site? Talk about a design ahead of it's time. Read some of the Crowhurst stuff on parallel feed from the 1950's.

Cheers,
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I'd love to have a mint Model T. Bet it would get more attention at the party than a Ferrari.
Viridian, i was referring to the F as a point source simply because all of the sound references back to ONE point of origin i.e. a single driver. As to what is classified as a "point source" in terms of radiation pattern, that may be completely different. However, one does need to point out that your elimination of the F as a point source based on the comments that you made would rule out ANY speaker that used any type of a baffle, a grill that caused diffraction, etc... due to the distortions ( peaks and nulls ) that they would generate. As was discussed here previously, a radiating sphere suspended in space is the only ideal "point source". Sean
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