Are there any RS225P-8A Two way designs out there?

[DSchreck]

Is there any two way designs using the 8 ohm 225P?

I recently got my hands on a Pair of the 225's a single RST28F and a single RS100-4 for very cheap and might finally do my first build if I can find either a

Two way using the 225p + RST28f or different tweeter

or

Maybe a 3 way using all 3 drivers I have on hand ( I would have to get another RS100 & RST28F)

Something like a "big bookshelf" would be Ideal

I've never designed or built anyone else's designs and don't have measuring equipment so I'd have to do a existing design. I have all the tools needed for building the enclosure, So that part won't be a problem. I just need to find something that would work with these drivers ( at least the 225's since I have a pair already)

If anyone has any ideas I'm all ears

Thanks

[Whitneyville1]

I'm not aware of any "proven" RS225P-8A/RST8F designs, but Paul Carmody's "Core" based on the RS225 and NLA Dayton RS28 (A or F) would be a "starting point". A totally new XO would be needed and different tuning for the woofer, but I think a very listenable speaker is possible to be built with the drivers you suggest. I don't think a three-way would be required as the RS225P-8A reaches pretty high with controlled break-up and the RST is claimed to reach pretty darn low. That doesn't always make drivers "hand-off" well to each other with a simple XO, but it usually doesn't hurt either.

I'm betting you could get lots of help with a big bookshelf or a floor stander, working out the XO and voicing. A floorstander should get an F3 into the 40s, so for most music, a sub would be optional in most rooms.

[DSchreck]

I've been searching for a few days now and so far nothing, I've seen a few state they are working on a design with the 225p but not sure if anything ever came of it.

I had a feeling when I bought these drivers I wouldn't be able to find any builds using them, but they were so cheap I couldn't pass it up. 90.00 for all 4 drivers and they are still new in the boxes. The rst is out of stock but due back any day now. so I would need to pick up another when I can.


I'll keep searching around and maybe I'll luck out, If not who knows lol.. Maybe I'll throw the 225's in my car doors and run them active.

Thanks for the reply.

[fpitas]

I haven't tried it, but I'm guessing all that peaking (cone break-up, probably) going on above 2.5kHz will be difficult to deal with in a 2 way without a lot of EQ. Even if you EQ the on-axis flat, the off-axis will then have a big notch.

[PWR RYD]

I think a two way with the RS225P-8A shouldn't be too difficuct at all and could sound very nice. I wouldn't use the RST28F though. It sounds lifeless to me and sounds bad when pushed too low (even if they claim it can). I'd go with the DA25BG08-06. I used it in my Indy 20/20 theme project and crossed it at 1800 Hz quite easily. It's a very nice sounding tweeter for only $26.46.

Wolf also used that tweeter in his Zingers project, a two way with an 8 inch woofer (SD215A-88). It sounded very good. The RS225P is a much better woofer that should sound even better (better cone material and motor design). The two woofers have similar breakups and Wolf was able to squash it down nicely.

Too bad those tweeters are out of stock. Seems like every driver I look at is out of stock at PE these days. Meniscus Audio has them in stock for just a few bucks more...

Well that's my 2 cents

[fpitas]

I think a two way with the RS225P-8A shouldn't be too difficuct at all and could sound very nice. I wouldn't use the RST28F though. It sounds lifeless to me and sounds bad when pushed too low (even if they claim it can). I'd go with the DA25BG08-06. I used it in my Indy 20/20 theme project and crossed it at 1800 Hz quite easily. It's a very nice sounding tweeter for only $26.46.

Wolf also used that tweeter in his Zingers project, a two way with an 8 inch woofer (SD215A-88). It sounded very good. The RS225P is a much better woofer that should sound even better (better cone material and motor design). The two woofers have similar breakups and Wolf was able to squash it down nicely.

Too bad those tweeters are out of stock. Seems like every driver I look at is out of stock at PE these days. Meniscus Audio has them in stock for just a few bucks more...

Well that's my 2 cents

Like I said, I haven't tried it. But how would you deal with all that peaking above 2.5kHz?

[LOUT]

Like I said, I haven't tried it. But how would you deal with all that peaking above 2.5kHz?

Should an 0.6uF-0.8uF parallel capacitor on the inductor be enough to notch it down?

Maybe something similar to this (though not this exactly, because this doesn't have baffle diffraction or actual Z-axis or anything like that addressed with any precision):

I've read the RST28F is safe to cross lower than this (I think some builds mention it down to 1500-1700hz and performing well), I'm assuming by then they add a capacitor to go 3rd-order on the tweeter.
The woofer will probably want a subtle, wide+shallow dip somewhere around 300-900hz to account for the BaffleStep bump around there...I'm assuming both of these things might also help push that 2.5Khz+ woofer squiggly farther down (though I'm unsure if it does anything too ugly since it's a paper cone which maybe doesn't "ring" like some aluminum breakup might...just a guess though).

[fpitas]

Yeah, you might be able to squash it that way. The further in the stopband the peak is, the better, so a low cross is a good idea. A waveguided tweeter crossed around 1kHz might be a good plan, too.

[DSchreck]

I think a two way with the RS225P-8A shouldn't be too difficuct at all and could sound very nice. I wouldn't use the RST28F though. It sounds lifeless to me and sounds bad when pushed too low (even if they claim it can). I'd go with the DA25BG08-06. I used it in my Indy 20/20 theme project and crossed it at 1800 Hz quite easily. It's a very nice sounding tweeter for only $26.46.

Wolf also used that tweeter in his Zingers project, a two way with an 8 inch woofer (SD215A-88). It sounded very good. The RS225P is a much better woofer that should sound even better (better cone material and motor design). The two woofers have similar breakups and Wolf was able to squash it down nicely.

Too bad those tweeters are out of stock. Seems like every driver I look at is out of stock at PE these days. Meniscus Audio has them in stock for just a few bucks more...

Well that's my 2 cents

Thanks I'll take a look at those DA25BG08-06 you mentioned,

I noticed everything has been out of stock at PE too.

[a4eaudio]

I wouldn't use the RST28F though. It sounds lifeless to me and sounds bad when pushed too low (even if they claim it can).

Have you heard the RST28A in a design that tries to push it down to 1500Hz, which is where it is claimed it can go? I know the original RS28A could go low and was widely praised, but I haven't heard much about the new aluminum version.

[Whitneyville1]

Robbing from Paul Carmody's Amiga design, the Vifa DX25TG59-04 (out-of-stock???) would seem to HAVE to work with a paper cone RS225P if it worked with an aluminum coned version, so THAT'S an option. Again, some re-working of the XO will be needed, but you'll be working on "the money side" with a paper cone having a gentler top-end break-up. The Amiga is 4th order-ish at 2000Hz with the RS225 so all the +2500Hz hash on the RS225P-8A should be squashed -50dB or more. In Mr. C's 30 Liter floorstander the paper cone should deliver about 40 Hz.

The RST28A is an option I haven't heard, but have been very interested in with either the classic RS225 or the RS225P-8A, in other words, a new "Core".

Take a look at Paul's site Undefinition.com and look at his designs. Re-inventing the wheel starting with a square is the hard way! Keep me informed on your progress please. A reconstructed right shoulder (like Jim McMahan's) is preventing me from making sawdust and making my own mistakes! Ever typed with one hand??? Second surgery soon!

HAPPY FOURTH! Me and the USAF kept you safe while we slept! ;)))

[DSchreck]

Robbing from Paul Carmody's Amiga design, the DA25BG08-06 (out-of-stock???) would seem to HAVE to work with a paper cone RS225P if it worked with an aluminum coned version, so THAT'S an option. Again, some re-working of the XO will be needed, but you'll be working on "the money side" with a paper cone having a gentler top-end break-up. The Amiga is 4th order-ish at 2000Hz with the RS225 so all the +2500Hz hash on the RS225P-8A should be squashed -50dB or more. In Mr. C's 30 Liter floorstander the paper cone should deliver about 40 Hz.

The RST28A is an option I haven't heard, but have been very interested in with either the classic RS225 or the RS225P-8A, in other words, a new "Core".

Take a look at Paul's site Undefinition.com and look at his designs. Re-inventing the wheel starting with a square is the hard way! Keep me informed on your progress please. A reconstructed right shoulder (like Jim McMahan's) is preventing me from making sawdust and making my own mistakes! Ever typed with one hand??? Second surgery soon!

HAPPY FOURTH! Me and the USAF kept you safe while we slept! ;)))

I'll check out pauls site, I'd have no problem buying the DA25BG08-06 to make this happen. After the holiday weekend I could order the tweeters.
Thanks for replying.

Happy 4th and Thank you for your service.

[Wolf]

The Amiga uses the RS180, not the RS225.

Craig, thanks for the props. I really like the DA25BG, as it sounds great and reaches low. I bet it would mate-up with the RS225P.
Later,
Wolf

[Geoff Millar]

Depending on the room size and desired dB output, you could also consider matching the RS225 with a small full range such as the VIFA TC7 - the "Obsidian" speaker based on the RS225-4 (I think it was the 4 ohm version) and the TC-7 won its category at a speaker design competition a few years ago.

You could cross the RS225 quite low and avoid the break-up 'nasties', although the paper cone driver won't be as good off-axis as a dome tweeter. I've also used the Peerless DA25, it's excellent.

Geoff

[norman bates]

Over on diyaudio, they cross rs225-8 to a ss 10f/8424 6db.

Not cone and dome design though.

not quite time / phase aligned if you are into that either, but real close.

https://www.diyaudio.com/forums/full...f-monitor.html

[Whitneyville1]

I'm sorry Wolf! My brain has had RS180 in place of RS225 since this thread started. Early senility or plain stupidity working overtime.