My PE order of Dayton RS28F-4(ohm) tweeters showed up today; must say, they look very well made and nicely packed.
http://www.parts-express.com/pdf/275-140s.pdf
Need help with second order xo design. The plan is to cross them over 2,300 - 2,400hz. Checked some charts and on-line calculators; they were all over the place, but the general idea is:
C1 - 8.2uf
L1 - .5mh
I'll probably use twist type L pads for attenuation for now, but have section of resistor for l pad which I can slip in later.
Can anyone suggest a second order xo?
http://www.parts-express.com/pdf/275-140s.pdf
Need help with second order xo design. The plan is to cross them over 2,300 - 2,400hz. Checked some charts and on-line calculators; they were all over the place, but the general idea is:
C1 - 8.2uf
L1 - .5mh
I'll probably use twist type L pads for attenuation for now, but have section of resistor for l pad which I can slip in later.
Can anyone suggest a second order xo?
What woofer are you using? What are the baffle dimensions? What are the driver locations relative to the bottom of the cabinet?
A fairly accurate simulated crossover could be worked up for you with that information provided.
A fairly accurate simulated crossover could be worked up for you with that information provided.
Thanks for taking a look Jay.
It's a MTM with 2 -6.5 (8ohm) in series - 16ohm. The front is small, only 1/2" on each side of woofer.
The bass is rock solid, with a very heavy sound. Listing to them now with ScanSpeak tweeters. The Madisound Speaker Store
The Dayton are for the prototypes which are the same box(s), etc.; can compare the two sets when done, side by side.
*both tweeters are in the $50 range, both have great reviews.
It's a MTM with 2 -6.5 (8ohm) in series - 16ohm. The front is small, only 1/2" on each side of woofer.
The bass is rock solid, with a very heavy sound. Listing to them now with ScanSpeak tweeters. The Madisound Speaker Store
The Dayton are for the prototypes which are the same box(s), etc.; can compare the two sets when done, side by side.
*both tweeters are in the $50 range, both have great reviews.
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Jay, Thanks for working on this, and apologies for beginner mix-up.
Although, before opening this post I was guessing that larger woofer coils may be needed, but never would have guessed 6.0mh.
I did try reversing tweeter leads the other day (Scanspeak tweeters) and not much sound loss when disconnecting them; so they must have been xo'ed way too high and acting like super tweeters.
In luck here, have parts, even a pair if 6.0 lam, 14gauge coils.
Thanks again!!
Although, before opening this post I was guessing that larger woofer coils may be needed, but never would have guessed 6.0mh.
I did try reversing tweeter leads the other day (Scanspeak tweeters) and not much sound loss when disconnecting them; so they must have been xo'ed way too high and acting like super tweeters.
In luck here, have parts, even a pair if 6.0 lam, 14gauge coils.
Thanks again!!
If you check the Parts Express Techtalk forum you will find a number of designs w/ the RS28F/A.
They are relatively interchangable and the various designs will give you a place to start.
They are relatively interchangable and the various designs will give you a place to start.
Oh really, I did call the tech support number, no mention of that.
Any thoughts on MMT vs. MTM front baffle?
Might make another set if MMT is a better design. (or could fill holes and re-cut existing mock up boxes MMT)
Any thoughts on MMT vs. MTM front baffle?
Might make another set if MMT is a better design. (or could fill holes and re-cut existing mock up boxes MMT)
Won't be long now, one cardboard "breadboard" finished.
Odougbo hopes 3rd times the charm
Odougbo hopes 3rd times the charm
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Success! Well for the most part, had to much high end - tried many combination of resistors and ever a smaller 8.2 cap. The smaller cap left a very noticeable "hole" in the middle, so put the 10uf back in.
As you can see I did install a L Pad and only it only needed a 1/3 of a twist (which may be typical).
So yes very nice, good imaging, solid bass, a wide range of sound.
Will have to find a way to remove L pad - maybe two amps or something; passive bi-amp, but still would need a way to attenuate the treble.
Jay thanks for helping out with this 😀
Thumbs up on the tweeter!
As you can see I did install a L Pad and only it only needed a 1/3 of a twist (which may be typical).
So yes very nice, good imaging, solid bass, a wide range of sound.
Will have to find a way to remove L pad - maybe two amps or something; passive bi-amp, but still would need a way to attenuate the treble.
Jay thanks for helping out with this 😀
Thumbs up on the tweeter!
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Usually yes. A zobel drops the top end of a driver by controlling the impedance. The 5.1uf, 3 ohm zobel I pm'd you will give a very slight droop to the treble response. You can also pair that with a slightly higher value for r11 until you get the balance you're happy with.
Here's what you should get with the zobel added. The gray line shows what changing R11 to 5 ohm's would get you. An adjustment of R11 in 1 ohm increments will change the treble by that much, up or down. Notice how the top of the impedance response is tilted downward, and the filter transfer function shows a downward tilt. This is the effect of using a zobel on a tweeter.
The only questionable part of a pure simulation like this is getting the phase alignment right, but the driver levels are going to be correct based on what you are seeing.
The only questionable part of a pure simulation like this is getting the phase alignment right, but the driver levels are going to be correct based on what you are seeing.
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Will add Zobel today - sorry I missed that, but the L pad gave me an idea what they can sound like (when finished). I did have to tweak it several times, but they sound wayyyyyy bigger than they are; with a sub-woofer like sound.
This xo is 10x better than the one I had (post #3), e.g. I started to realize that the sound stage would focus 6' to the right (very strange). All that craziness is gone now.
Again Jay, thanks!
This xo is 10x better than the one I had (post #3), e.g. I started to realize that the sound stage would focus 6' to the right (very strange). All that craziness is gone now.
Again Jay, thanks!
Oh yeah...much better just as shown.
Will try slightly larger resistor at R11, just for experiment.
Will try slightly larger resistor at R11, just for experiment.
This sounds better every day; there were a lot of new parts and new drivers, so a few days of break-in is expected.
Also...switched to a Luxman M-117; best sounding amp here.
used 6.8 at R11, which also sounds very nice, balanced.
I think I saw a build where the same tweeter does not have a zobel - I don't know about that, it has some sharpness to it (without one).
Also...switched to a Luxman M-117; best sounding amp here.
used 6.8 at R11, which also sounds very nice, balanced.
I think I saw a build where the same tweeter does not have a zobel - I don't know about that, it has some sharpness to it (without one).
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