[mresseguie]

Hello. SB Acoustics' new 7 1/2" Satori woofers are now available. Since I have a pair of Adelphos (6" Satori midwoofers, Satori tweeter) and a Selah Audio Ancora (6" Satori, 5" Satori, Scan Speak Illuminator tweeter), I've been waiting for the next addition to the Satori lineup. Well, they're now available at Madisound, so I checked them out only to discover something I consider odd. The new, larger 7 1/2" woofers do not play as low as the 6" midwoofers.

I had expected the opposite. I expected the 7 1/2" woofers would be used to produce the lower frequencies in a floor standing model (for example). Are these new drivers intended to be used in a two-way design like the Adelphos, but more efficiently and/or reproduce music with less distortion than their smaller cousins?

Anyone have thoughts on this? Do you suppose these are intended to compete with the Seas Exotic woofers?

Michael

[JohnR]

Nice woofer They model about the same. For a floorstander they could be tuned a bit lower and won't run out of excursion as quickly as the 16.

[ricardojoa]

Based on the madisound info, it seems they do have a lower f3 down to 40hz with a much larger enclosure while the 6 plays down to 45hz with a smaller enclosure.

[richidoo]

The published resonance (Fs) of 7" is 32Hz while 6" is 28Hz. VAS (suspension tightness - springrate) and Mms (moving mass) affect the driver resonance. They have same VAS 48 liters, but Mms differs 17.9g (7") and 12.4g (6".) So shouldn't the 7" be lower Fs?   

Technically they will both "play" just as low as the signal you feed them, resonance is not a brick wall. But resonance does limit how low the port can be tuned, and port tuning limits how low you can play a ported box without damaging the driver.  SPL and detail will fall off due to falling acoustic impedance (the air just sloshes out of the small cone playing that low) so the port is doing all the lifting down that low anyway. In a hifi speaker the tuning will usually be a bit higher than Fs for best SQ. Your Adelphos are nominally tuned to 35Hz even tho the driver Fs is 28Hz.

SB also has a new neodymium version of the Satori tweeter with even higher 96dB sensitivity. It should be even more detailed, although I find my ferrite Satori to be plenty detailed enough for my taste.

[Rick Craig]

Hello. SB Acoustics' new 7 1/2" Satori woofers are now available. Since I have a pair of Adelphos (6" Satori midwoofers, Satori tweeter) and a Selah Audio Ancora (6" Satori, 5" Satori, Scan Speak Illuminator tweeter), I've been waiting for the next addition to the Satori lineup. Well, they're now available at Madisound, so I checked them out only to discover something I consider odd. The new, larger 7 1/2" woofers do not play as low as the 6" midwoofers.

I had expected the opposite. I expected the 7 1/2" woofers would be used to produce the lower frequencies in a floor standing model (for example). Are these new drivers intended to be used in a two-way design like the Adelphos, but more efficiently and/or reproduce music with less distortion than their smaller cousins?

Anyone have thoughts on this? Do you suppose these are intended to compete with the Seas Exotic woofers?

Michael

The new driver was designed based on what tradeoffs SB wanted. In this case they optimized for upper end frequency extension and sensitivity. With greater surface area and excursion it's basically the big brother of the MW16.

As far as comparing with the Seas Exotic these are quite different. Much greater excursion capability with the SB so for a 2-way it's the better choice if you don't use a subwoofer. Also a much better value (the SB) and with the 4-ohm version very close in sensitivity.

[mresseguie]

Thank you, everyone, for replying. I now have a much better understanding of these new drivers than I did before I asked. I wish there were a "Learn to Read and Understand Driver Specs" workshop available at my local community center or online.

In addition to posting here, I emailed Madisound for information. the rep (Brian) who answered told me the following:

"Like nearly everything loudspeakers make (sic), there was a customer for it.  OEM sales drive all the innovation.  I would guess they wanted a more robust driver for a 2-way than the 6" was offering.  Eight inch drivers are either built for bass or for midbass, they don't seem to do both very well.  This driver should offer a higher power handling 2-way.

I'll ask them for more information and post it to the site."

After reading all the replies, I went back to Madisound's website and noticed some details that had slipped past before. The 4 Ohm version has higher sensitivity, but the suggested box alignments are different.

Here are some box alignments you might consider using.

around 0.25 cubic feet sealed for an F3 of 90Hz
0.5 cubic feet with a 2" vent by 8" long for an F3 of 55Hz
0.8 cubic feet with a 2" vent by 6" long for and F3 of 45Hz

8 Ohm version
Here are some box alignments you might consider using.

around 0.3 cubic feet sealed for an F3 of 80Hz

0.7 cubic feet with a 2" vent by 7" long for an F3 of 50Hz
1.0 cubic feet with a 2" vent by 5.5" long for an F3 of 45Hz
1.2 cubic feet with 3" vent by 8" long for an F3 of 40Hz

Allow me to blurt out my ignorance:

Under what circumstances would someone choose the 4 Ohm version over the 8 Ohm version? [I understand the 4 Ohm version presents one with greater sensitivity, and...slightly higher low-end for better SQ??]

I guess I hadn't really expected the new MW19P to compete with the Exotic, but I have to admit I was rooting for the Satori anyway. 

[Rick Craig]

Thank you, everyone, for replying. I now have a much better understanding of these new drivers than I did before I asked. I wish there were a "Learn to Read and Understand Driver Specs" workshop available at my local community center or online.

In addition to posting here, I emailed Madisound for information. the rep (Brian) who answered told me the following:

"Like nearly everything loudspeakers make (sic), there was a customer for it.  OEM sales drive all the innovation.  I would guess they wanted a more robust driver for a 2-way than the 6" was offering.  Eight inch drivers are either built for bass or for midbass, they don't seem to do both very well.  This driver should offer a higher power handling 2-way.

I'll ask them for more information and post it to the site."

After reading all the replies, I went back to Madisound's website and noticed some details that had slipped past before. The 4 Ohm version has higher sensitivity, but the suggested box alignments are different.

Here are some box alignments you might consider using.

around 0.25 cubic feet sealed for an F3 of 90Hz
0.5 cubic feet with a 2" vent by 8" long for an F3 of 55Hz
0.8 cubic feet with a 2" vent by 6" long for and F3 of 45Hz

8 Ohm version
Here are some box alignments you might consider using.

around 0.3 cubic feet sealed for an F3 of 80Hz

0.7 cubic feet with a 2" vent by 7" long for an F3 of 50Hz
1.0 cubic feet with a 2" vent by 5.5" long for an F3 of 45Hz
1.2 cubic feet with 3" vent by 8" long for an F3 of 40Hz

I guess I hadn't really expected the new MW19P to compete with the Exotic, but I have to admit I was rooting for the Satori anyway. 

But the Satori does compete with the Exotic at a far lower price.