Parts Express Denovo SEOS horn and new compression drivers

I

IlikeitLOUD

Horny in Ohio
The polymide compression driver for 50 bucks and the 35 dollar Denovo SEOS horn are stupid good. Probably the best deal in horns and drivers ever. Excellent choice for 1000 cycles up. Have a pair mated up here with some mid bass horns loaded with a JBL 10" and it better then the thousands of dollars of drivers and horns it replaced. :) I had to do a little tweeking on the midbass horn to get them to sound good past the 1K crossover point and after that it all snapped into place. The Dayton compression driver is at least the equal of the B&c 250 it is a copy of. I've had them before and don't remember them sounding or measuring this good. It could be the horn but the combo is surely an upgrade the old Altecs, JBL, EV horns normally used in the 1K up range.:thmbsp:

http://www.parts-express.com/pe/showdetl.cfm?partnumber=300-7070

http://www.parts-express.com/pe/showdetl.cfm?partnumber=270-402
 
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Are the horns CD? Do they need a CD crossover? That is very good pricing and with the Dayton Classic 300 12" woofer, they would make a killer speaker for very little money.
 
djnagle said:
Are the horns CD? Do they need a CD crossover? That is very good pricing and with the Dayton Classic 300 12" woofer, they would make a killer speaker for very little money.
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I'm using a 4th order electronic crossover without any passive or active EQ - they don't load the low end (1-3k) as well as a round tractrix horn would but are pretty darn linear at around +-3 db 1k to 10k in these SEOS. Haven't measured the impedance yet for a passive high pass but I imagine it wouldn't be too difficult to do a second order at 1.2K. Dispersion is excellent. In my room normally wide dispersion mid horns sound bad and I prefer round 60 degree horns but these sound great. I think it is due to the constant directivety being designed so well into them. Look at the graph Parts Express published:

http://www.parts-express.com/pedocs/tech-diagrams/300-7070-parts-express-technical-diagram.pdf

They really are a deal when used together with the Parts Express 250P compression drivers. I might try to tweak up the top octave a hair but they sound very extended and detailed in the high end in these horns so it may not be better. I've had (have) lots of drivers and horns from TAD, JBL, Altec, B&C. 18 sound, Celestion, EV, Emilar, Radian ect.. lots, plus lots of horns, this combo is the best DEAL I've run across :music: and will probably stay in my big rig for a while
 
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How would you compare these to the Selenium DT210/220Tis so many of us used on waveguides?
 
Andyman said:
How would you compare these to the Selenium DT210/220Tis so many of us used on waveguides?
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Wish I could tell you but i never had those. Titanium normally to me sounds a bit harsh and upfront. These are detailed smooth and relaxed. I compared them with Radian 475's, Celestion 1425's, and Emilar ec175 directly and these beat them all save the top end on the Celestions - the Celestions are only good 2.5k up though but the top end is really excellent
 
djnagle said:
Are the horns CD? Do they need a CD crossover?
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Yes.

seos12_horizontal_1_4.jpg
 
Well sure, that's fine for you if you think it's fine, but the question wasn't about what you like, it was whether or not these have characteristic constant directivity response, and they do.

As far as subjective response, what you are getting without any special compensation is actually quite a bit brighter than neutral. If we ignore the top octave, they have a broad +4dB peak centered at 4kHz. That's bright, although that could be easily be obscured in any direction depending on how things add up at crossover and where you've got the relative level of the midwoofer (if adjusting by ear, I think most people would tend to turn up the woofer to meet or exceed the 4k peak).

Presuming perfect summing at crossover and a flat response below this graph (easier said than done), you need to pull the response down to something close to this gradually falling response if you want results that sound like a very neutral, monitor-type speaker. It is relatively easy to incorporate some additional BBC-dip-like attenuation into the CD compensation as well, if you want them even mellower.

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Yes, the combination I have here does not measure like the published graph. The graph does shows the horns are respectable "cd"
 
Looks like your measurement has a reflection around 3ms. You need to set the gate before that. Also looks like you're 180° out of phase - need to flip polarity there, or add delay if you have that.

edit: sorry, didn't notice you had the time scale on meters - 3 meters is where the reflection appears to be.. in any case, zoom in on that impulse and gate your measurement.
 
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rrrgh, AK is freaking out on me and not responding, but I also just realized your frequency response is on linear scale (put it back to log, that doesn't make sense with how audio works), so nevermind about that polarity.

EDIT AGAIN because now I see your last post: that sure is quite a bit different before the CD rolloff starts. This is on the waveguide axis? Let's see one with the reflections gated out please?
 
Nah it's fine, as you can see above (edits) it took me a while to notice what you were doing completely, and AK being slow is making it hard to correct myself. I get it now, though. Seems like you are getting a different response than the DE250 published response, which is a little curious. Zoom way in on the impulse, and gate the measurement before the first reflection. Should only clear up the top end, but worth doing anyway.
 
I need to hit the hay , I'll get some better reflection free measurements tomorrow. Yes it's dead on axis.

This is the Parts Express driver not the B&C, not sure if you knew that.
 
It would be nice to hear a side by side comparison to the B & C. There is lot sof knowledge about the B&C so a comparison would help a lot of us in our future purchases
 
IlikeitLOUD said:
This is the Parts Express driver not the B&C, not sure if you knew that.
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Yep, that's the only reason I'm curious :). If your measurements continue to look like that, it would seem it's plenty different enough not to be equivalent, crossover-design-wise (which would also mean side-by-side comparisons like kneedeepinit just mentioned are not worth much).
 
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