High XO 10"

[Jonasz]

Are there any 10" woofers suitable for a xo at 500-600hz? The thought is to partner it with a RS52 to play at moderate levels in a dipole. Even if the volume isn't that strong I would like to keep an effortless midbass reproduction hence the 10". The drivers I've thought about so far are Dayton RS10", SS8565-00 and Seas Excel 10".

Any ideas?

[Nathan P]

IIRC, The Dayton RS315 HF can be played really high.

[---k---]

Note, there is the Dayton RS Woofer, the RS270S, and then the Dayton RS Subwoofer, the RSS265.

Augerpro's measurements.
RS270S: Images not available

[dlneubec]

Here is a nearfield of the RSS265HF in a 31L tapered TL. The green is the RSS265HF and the pink is the TL terminus output. The other is the impedance and impedance phase of the same.

[dlr]

My likely first choice

Are there any 10" woofers suitable for a xo at 500-600hz? The thought is to partner it with a RS52 to play at moderate levels in a dipole. Even if the volume isn't that strong I would like to keep an effortless midbass reproduction hence the 10". The drivers I've thought about so far are Dayton RS10", SS8565-00 and Seas Excel 10".

Any ideas?

Two reasons I'd suggest the SS8565. First, it's off-axis response is arguably the best of the three. Second, the breakup is higher than the others and is a bit less extreme and probably easier to control. It's still going to be a stretch to run them that high, you'll really have to go 4th order IMO.

I've used the 8565-01 for years at 350-400 LR2 and have been very satisfied with it. I think that you'd may want the -00 version if you go with the SS. LR4 at 600 should be easy, but 800 might be pushing it. The latter will actually have the breakup of the SS and the Seas farther down than my 400 LR2, so I would suspect the primary issue to be in the area of directionality transition. I also personally would not consider the Dayton to work at 800Hz given the glitch in response at 1K. That one can't practically be equalized without DSP.

Another consideration, though again it may not be the primary one, is distortion. The linear distortion from fundamentals that have lower harmonics coinciding with the breakup area and IMD products will be more of a concern as the Fc of the lowpass goes up. In that area, I would also expect the 8565 to be somewhat better, again due to it's slightly less dramatic breakup. The non-linear distortion from the motor of any particular driver shouldn't change a lot with the lowpass, so consider the individual driver's distortion profile in that area without concern for the lowpass.

All that said, are you planning on equalizing the response? The distortion due to the displacement should be a higher priority for a dipole. I've not compared the displacement of these drivers for a dipole, so take my input with a grain of salt.

[Paul W]

Interested to see which drivers pop up in this discussion.

Here is the W26 on a small OB with a layer of 1/4" wool felt wrapped in a semi-circle across the back of the baffle. Needs a healthy trap at 4k.

What about the Aurasound 10/12"?

Image not available

[JonMarsh]

Aurasound NS10-513 is one to consider. Very well behaved cone, nice bottom end, moderate travel.

[Jed]

Aurasound NS10-513 is one to consider. Very well behaved cone, nice bottom end, moderate travel.

85DB
Aurasound NS10
Distortion attached.


Images not available


If you can deal with the impedance dip of 2.5ohms (with a passive crossover in place) you're all set. Or you could use a pair in series like I'll be doing eventually as I have 4 of them.

Jed

[Jonasz]

---k--- I was thinking about the RS270. The extra xmax of the RSS won't be necessary because it will have a highpass in the 100-120 hz region.

Looking at Augerpro's measurements the RS looks pretty good. One question though, will the 4th and 5th order distortion around 500 hz be audible or could it be considered insignificant?

[augerpro]

I wouldn't worry about that spike around 500 hz too much. One thing you have to watch out for in these plots are anomalies that are most likely a measurement artifact. I believe that peak may be one. It's very narrow and doesn't correspond to anything in the FR or Z. Another thing to watch for is nice symmetric nulls. You'll see these in both mine and Zaph's plots for tweeters quite a bit. In fact I've never been real happy with my Visiton KE25 measurement because the nulls were so prominent it was hard to get a good idea of the real distortion.

I've thought about using the RS270 for open baffle too. It's such a nice driver for the money. But it's xmax is limited...don't know just how an open baffle would require though...

[Jim Holtz]

This brings up a question I've had in my mind ever since Jon posted that a di-pole should extend from 70 Hz. - 1K Hz. Just what kind of xmax does it take to to get down to 70 Hz. open baffle, or in my case in a transmission line/open back design?

Jim

[augerpro]

SE can model this I think in the enclosure designer. I'll check this out. What I can say is Jon is pretty spot on. I had some PA dipoles I was building and the model suggested I would be down 6 dB where I would then cross to sub. The actual prototype I built appears to be down almost 6 dB by 200Hz! I have to verify my measurement since dipoles are tricky but if that's correct I may ditch the project. At the time my experience was such that I would accept some shortcomings in the design because it was an experiment. At this point I don't think I really want to accept those compromises any more. Considering it's a 3 way the XO would be extremely expensive...too much so for a little experiment.

[Jonasz]

Jim: If I understand your question correct I believe this Excel document from SL can answer your question.

http://www.linkwitzlab.com/SPL-dependent.xls

[Piotr]

Even though I've used the 8565-01 in a dipole I would not pick it again. The reason is I simply believe that the Classic and Revelator 10" alu-woofer from SS is better. Smoother Fr and no wiggles in the impedance graph that in 8565 indicates cone resonances around 500Hz.

Also the 8565 has a much higher breakup peak than the alu-woofers and at a lower frequency as well.

I would look at the Revelator or Excel W26 and perhaps Aurasound as well.


I used 8565 with 2x C92 in a 2.5way dipole with good results. Now I use an array of 3x W22 to cover about the same range that 8565/C92 combo did and the resolution is clearly higher, only lacking the low bass omph from the old speaker but that is likely most a Fr thing.

For a small three way, three driver dipole, I would most likely pick the Revelator 10" alu driver. If this speaker would be used as a main panel with subs I'd look at Excel W26.


/Peter

[Paul Ebert]

If you want a cheaper candidate, you might want to consider the Peerless SLS 10" subwoofer ( 830668 ). The frequency response and z plot look good quite high.

[Jim Holtz]

Jim: If I understand your question correct I believe this Excel document from SL can answer your question.

http://www.linkwitzlab.com/SPL-dependent.xls

Hi Jonaz,

That was exactly what I was looking for. I had searched SL's website but not found what I was looking for. :T

Thank you!

Jim

[---k---]

---k--- I was thinking about the RS270. The extra xmax of the RSS won't be necessary because it will have a highpass in the 100-120 hz region.

I was just being nice and posted the link to the data first. I don't have any real first hand experience with the driver, other than hearing it in CJD's 3-ways. I don't want you to think I'm necessarily recommending or not recommending it.

[Jonasz]

dlr: Thanks for a lot of good information about the SS8565. I've decided against it in this projekt due to the same reasons Piotr mentions. I may however use it in a regular boxed 3-way sometime, when I've heard them with excellent results in Respons top model. www.responsloudspeakers.com They have however also began to use one of the newer SS-designs.

Are your speakers still (if I remember correctly) a 8565, 12M and OW1 combo?

[Jonasz]

I guess the RS270 (budget) and the Aura (deluxe :B ) are the answers to this question. On a side note, I have four Seas W22, how would a WTMW compare to a TMW when it comes to imaging and powerresponse and so on? When we're at it, it would be interesting to know the differences between TMW, WTMW and WMTMW. Does any of the gurus have an easy to grip answer to this?

[Piotr]

SL seems to (if memory serves me well) prefer the imaging from the WMT Orion compared to earlier designs like AA and Phoenix.


I have done several projects but have not compared the proto's in the same room but I'm leaning towards MT (or WMT.. or WWMT) for better soundstaging. Maybe a point source has a more natural presentation. Less reflections and better control over diffraction can also be the result with less bafflesurface and drivers surrounding the tweeter (and mid).

My stand is point source or line source nowadays.

edit: there is one layout I think of that can be good if limited vertical dispersionis the goal and a line source is out of the question. WWWMTM perhaps with a ribbon. Normally I don't prefer a typical MTM layout due to the big dip in power respons in the mids. I have never understood the obsession with good respons around the x-ing with MTM's, symmetrical loobing yada yada and then the designer totaly forget about the huge dip in the midrange.


/Peter

[dlr]

Yes, that's the combination

dlr: Thanks for a lot of good information about the SS8565. I've decided against it in this projekt due to the same reasons Piotr mentions. I may however use it in a regular boxed 3-way sometime, when I've heard them with excellent results in Respons top model. www.responsloudspeakers.com They have however also began to use one of the newer SS-designs.

Are your speakers still (if I remember correctly) a 8565, 12M and OW1 combo?

That's the latest incarnation. I've had a number of M/T combos over several years, but this one is by the best of the bunch that I've used.

[Piotr]

dlr,

did you ever try a bass unit with your C95T two way? (IOW making it a three way)


/Peter

[dlr]

Only tested quick-n-dirty

dlr,

did you ever try a bass unit with your C95T two way? (IOW making it a three way)


/Peter

I've got a Peerless 10" in a closed box from DIY 2002 and a Dahlquist active crossover with adjustable lowpass 40-400. I tried it with the Accuton and was fairly pleased, but I have no way of knowing how close to optimum it was.

Since I had stuffed the box almost as if it was closed, the port output is significantly damped, but it still has excellent extension as a 2-way. The crossover with the Dahlquist on lowpass (Accuton run full range) was likely better than if it had been a standard ported setup. Most often I've found the setting at 45-100 on the dial to be the limits of usefulness. I don't know the precise Fc with the Peerless, however, that's just setting by ear. I like the adjustable Fc and gain approach for testing this way. It does make the limits of any 2-way more apparent.

I've never been able to use only a 2-way for any length of time. In a smallish room, though, the Accuton is still pretty good on its own. But if I'm going to go 3-way, I wouldn't use that Accuton. I like small mids in a 3-way.