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Was the Snell Secret a Wide Baffle?

I often regret not buying old Snell A/III when I had the money and the space.

One of my all time favorite speakers. By now I'd have certainly had to throw it away. I'd not have the space, and those woofers with extra mass would long ago have pulled out of their frames.

One thing you don't realize unless you go looking for the pics, or owned one, was that the tweeter and midrange of these  speakers were, in my mind, very wide baffle designs. Yes, curved, but very wide.

Another Speaker I like, which I believe is based on a Snell design, is the Audio note AN/J, also has a relatively wide baffle, as do the Devore Orangutan. Of course, among my all time favorite speakers is the Sonus Faber Stradivari, a speaker I know can sound excellent even in acoustically challenged rooms.

What do you all think, have you heard the wide baffle magic?
erik_squires
audiokinesis
2,751 posts
 
Imo there are MANY things right about the Snell Type A. The wide baffle is one of them. When placed as intended (back against the wall), I think the extremely large radius round-over made a relatively smooth transition from baffle to wall. So you came close to getting the benefits of flush-mounting the speakers (studio main monitor style).

The Snell Type A implemented Roy Allison’s ideas about boundary interaction, placing the woofer close enough to the floor to be close-coupled across its frequency range, and then elevating the midrange driver high enough to (barely) avoid the floor bounce notch. The crossover frequency matters of course.

There were some interesting things going on in the high frequencies. First, there was a little ball of acoustically absorptive fuzz suspended just in front of the tweeter, presumably to reduce the on-axis "hot spot" and thereby make the speaker’s radiation pattern more uniform as we went up in frequency. Second, there was a rear-firing supertweeter (at least on the A/III), which presumably was to fill in the reverberant field a bit in the top octave where the front tweeter was starting to beam.

I think there MAY have been room for minor improvement in the woofer section. Perhaps the woofer could have been rear-firing instead of down-firing, so that it wouldn’t sag over time. This is assuming the greater path length would not have caused a problem in the crossover region; it might have, and that’s why Peter Snell went with down-firing. Not only was there an over-abundance of great ideas in the Type A, these ideas were extremely well executed.  

Duke
twoleftears's avatar
twoleftears
5,320 posts
 

Here’s a quote from Peter Comeau, the guy who designed the recent Lintons.

"Th[e] larger ported box, with its subsequent increased baffle size, helps solve a major problem in modern speakers, namely, the baffle step.

I grew up with large speakers with wide baffles, but, as speakers reduced in size over the years I noticed that something was missing from the sound and, when I stuck my head firmly into speaker design, I began to understand the acoustic problems caused by the baffle step.

Put simply, as the baffle size decreases, the point at which the acoustic radiation changes from hemispherical to spherical goes up in frequency. It also becomes sharper and narrower in bandwidth as the sides of the cabinet, and the walls and floor of the room, are further removed from the equation. So, this 6dB step in the power response becomes acoustically more obvious.

I believe that a thin speaker always sounds thinner throughout the midrange when directly compared to a speaker with more generous baffle width. Of course, as designers of modern, slim speakers, we compromise by adjusting for the baffle step in the crossover, but in doing so, we also compromise sensitivity. What starts out as a 90dB at 1W drive-unit often ends up as an 85dB system once we have adjusted for the power loss due to the baffle step."


unsound
7,333 posts
 
Many years ago, I was present when the late great Jim Thiel was demonstrating his then new CS 5's. At that time he pointed out that amongst many other things the curved baffle helped with early cabinet diffraction issues. Later, I asked him why he didn't use an even narrower, more tapered baffle. He responded by saying the baffle dimensions were in part due to market considerations, and that he would have actually would have preferred to use somewhat wider baffles. He explained that a wider baffle would permit a more consistent user experience as it would help mitigate the effects of placement for different users with different room dimensions.
 
erik_squires OP
16,395 posts
 
Really thorough take, Duke.

I think if it was made today, he could have gotten away without adding mass to the woofer, or as Vandersteen and others do, using a separate plate amp to power the woofer alone, because all that mass poured into that woofer was going to deteriorate the suspension no matter which direction it points.
audiokinesis
2,751 posts
 
" ...all that mass poured into that woofer was going to deteriorate the suspension no matter which direction it points. "
You're probably right, but with the woofer cone in the vertical rather than horizontal plane, you'd at least have the option of rotating the woofer cone 180 degrees every six months or so, as the Lowther guys do. 

That being said, yes nowadays a powered woofer section would arguably make the most sense. 

Duke
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