Size is the main reasoning. I can use 12's, stacked, so four cheaper lower excursion 12's in an enclosure about 12Wx25H. With typical 10's in an H/W I would probably need to use drivers with >12mm xmax, so maybe getting a little more pricey. Honestly some of the low priced MCM and pro sound drivers got me thinking about using the Ripole in this way, because I wouldn't want to buy eight 10's or 12's if they're $100 or more.
And yes, these drivers usually have highish fs so lowing this with the mass loading of the Ripole would be a plus.
Plus I thought it would look different and cool
I wondered about it affecting the sound, but I'm under the impression that if they're crossed under the QW resonance and notched that they should work. The mids I'm thinking of are 8's so they'll work down to the low 100's no problem. I really don't see why they would be any different within their pass band than any of the other folded dipoles. Please correct me if I'm wrong.
Is there a reason that they're not suited as woofer in a three way up to 150Hz?
I know that they're usually marketed as subwoofers, but dipole "subwoofers" just doesn't make much sense to me. High volume Sub bass is the very thing that dipoles don't excell in.
H/N/W or whatever folded dipoles seem to have a limited passband of about 30-200Hz which sounds just right to me for the bottom of a low crossed three way.
Please correct me if I'm wrong because the only experience I have with a Ripoleish alignment is an Alpine car sub that I tossed into a somewhat appropriate enclosure just as a test. I crossed it to a full range at 130Hz and notched the resonance without any glaring problems. Resonance was at 260Hz with the ten inch driver if I remember right.
I know that they're usually marketed as subwoofers, but dipole "subwoofers" just doesn't make much sense to me. High volume Sub bass is the very thing that dipoles don't excell in.
H/N/W or whatever folded dipoles seem to have a limited passband of about 30-200Hz which sounds just right to me for the bottom of a low crossed three way.
Please correct me if I'm wrong because the only experience I have with a Ripoleish alignment is an Alpine car sub that I tossed into a somewhat appropriate enclosure just as a test. I crossed it to a full range at 130Hz and notched the resonance without any glaring problems. Resonance was at 260Hz with the ten inch driver if I remember right.
You're right. I had forgotten to take another look at what the spreadsheet says about that that driver.
100Hz-97db, 141Hz-106db, 200Hz-115db.
That doesn't take into account an LR4 filter. I think 150ish should be doable.
Maybe my SPL goals just aren't reasonable for open baffle overall. I suppose with enough drivers and excursion anything is possible, but I'm not trying to get really expensive or complicated.
Even at loud levels, none of my other speakers can easily be driven to making any strange noises. I just wanted to have that same piece of mind with these.
Even at loud levels, none of my other speakers can easily be driven to making any strange noises. I just wanted to have that same piece of mind with these.
Again, it's my opinion that as soon as you start stuffing the backs of U frames the sound begins to take on the "box" tone. I think that any of the "frame" type dipole enclosures have to deal with resonances of one sort or another. (I find it unacceptable above 120hz or so.) I'd imagine stuffing the ripole would impart a tone shift just as it does with a u frame. Don't know how you'd get around that. Best to build them and see how you like it.
Yes, to an extent. I've done it a few years ago (to a W - style baffle, after giving up on ripoles).
In my experience, the improvement was audible, but not as much as one would think. All said and done, I think I'm done with ripoles. They just don't work well enough in practice.
Okay, I wasn't meaning stuffing to alter or reduce the resonance. I would still think a notch and lower xo is the way to go. I meant to reduce rear output to decrease dipole rolloff, of course there would also probably be a corresponding change in the resonance.
Zobsky, what don't you like about ripoles? The lower efficiency, sound, limited bandwidth, etc.? Please explain, maybe your subjective experience can save me some wasted time and money....or maybe I'd just try them anyways
Zobsky, what don't you like about ripoles? The lower efficiency, sound, limited bandwidth, etc.? Please explain, maybe your subjective experience can save me some wasted time and money....or maybe I'd just try them anyways
Okay, I wasn't meaning stuffing to alter or reduce the resonance. I would still think a notch and lower xo is the way to go. I meant to reduce rear output to decrease dipole rolloff, of course there would also probably be a corresponding change in the resonance.
Zobsky, what don't you like about ripoles? The lower efficiency, sound, limited bandwidth, etc.? Please explain, maybe your subjective experience can save me some wasted time and money....or maybe I'd just try them anyways
Low efficiency, sound just not impactful enough for the complexity and number of drivers, easy to bottom out drivers when trying to raise volume (as a result of even lower efficiency than open baffles).
If you do want the open open baffle, try a regular open baffle if you have the space or perhaps a u , w, or h (never tried the h config) baffle. Slot loaded open baffle ain't bad either if you have the space . None of these will get you to 20 Hz unless you get to very large baffle sizes but reasonable output in the 30 Hz can be expected depending in the driver and baffle dimensions
Okay, thanks. Are you saying that they have less impact than other open baffles or just that all open baffles are not as impactful as boxed speakers, which is to be expected.
I do want to try open baffle bass, but now honestly I'm considering going with a TL or BR if it's just not worth it. One thing that may keep me on the dipole bass path is that I have nice musical subs that'll probably be used with them, even with music. Just crossed in low.
I do want to try open baffle bass, but now honestly I'm considering going with a TL or BR if it's just not worth it. One thing that may keep me on the dipole bass path is that I have nice musical subs that'll probably be used with them, even with music. Just crossed in low.
Oh, I meant to ask...what's a slot loaded open baffle? Do you mean like the Nelson Pass design? That just seems like a ripole where the wings haven't been folded back.
When I do a google search mostly what comes up are ripoles. Then of course there are the design where the driver is mounted facing forward, but behind a slot. It seems like those would also reduce efficiency and I don't have the kind of room that those seem to need
When I do a google search mostly what comes up are ripoles. Then of course there are the design where the driver is mounted facing forward, but behind a slot. It seems like those would also reduce efficiency and I don't have the kind of room that those seem to need
To an extent, but mostly because they seem to run out of headroom very fast. Look at it this way, the effective baffle distance to cancellation is smaller in a ripole (compared to a regular open baffle). The ripole works by loading both sides of the driver via a narrow slot. What I'm trying to say is that the disadvantage of the smaller baffle overcomes the advantage of the slot loading. The Slot loaded open baffle (SLOB) works by loading only the front of the driver . The rear is open to the room, so to an extent there is unequal loading of the 2 different sides. But, the SLOB also requires a moderately wide baffle so the effective baffle width works in its favor. For what it's worth, here's a pic of a prototype I built last year that attempted to combine a slot loaded woofer and "BD-design orelino open baffle" system (closeout zalytron 1201PL 12" woofers) (wings not attached in pic) and the excellent (but sadly extinct) 5" Tang Band W5 1880 driver. I initially had 6 12" woofers per side but decided to use only 4 per side and mount the 5" driver in the slot. The slot is about 5.5" wide, for reference. The woofers ran from about 30 something Hz to about 150 Hz crossing over actively to the fullrange. The only issue with this system was the size. I don't have a convenient place to listen to it. Imaging each single speaker about 4 ft high and about 3 ft wide,
That's true in a way though partly because they don't typically dig as deep and also because they don't excite room resonances as much as monopoles.
No, keep experimenting. The true DIYer enjoys the process (failures and successes) more than the result. I've never had truly great results with bass reflex woofers, only with horn subs, TL or OB.
What's your woofer (if you already own it) and your desired frequency range?
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That's quite a stack there! Nice project. It seems like you would have an even shorter path, based on your picture, than the ripole would. I guessing better sensitivity though.
I haven't bought the woofers. I could use anything from four of the Dayton RS265's in flat or U/W/H/N to match my RS390 sealed subs. Or the Peerless SLS 10" drivers. If I used the stacked ripole design (4 10-12" per side) I would need to use cheaper drivers, say >$50 each. I was thinking of some of the cast frame MCM woofers for the stacked ripole. They have a number of them with good advertised specs for a Ripole for $30 or less. I would like to keep the overall cost of the woofer section under $500
I also want/need to keep them fairly narrow. that's why the folded dipoles interest me, knowing that they will have limited upper extension. I'd like to keep the baffle width to 12-13" for decent dipole response to higher frequencies and because I just don't have that much flexibility side to side. I'm also not a fan of the look or stepped baffles where they get narrower towards the top.
I haven't bought the woofers. I could use anything from four of the Dayton RS265's in flat or U/W/H/N to match my RS390 sealed subs. Or the Peerless SLS 10" drivers. If I used the stacked ripole design (4 10-12" per side) I would need to use cheaper drivers, say >$50 each. I was thinking of some of the cast frame MCM woofers for the stacked ripole. They have a number of them with good advertised specs for a Ripole for $30 or less. I would like to keep the overall cost of the woofer section under $500
I also want/need to keep them fairly narrow. that's why the folded dipoles interest me, knowing that they will have limited upper extension. I'd like to keep the baffle width to 12-13" for decent dipole response to higher frequencies and because I just don't have that much flexibility side to side. I'm also not a fan of the look or stepped baffles where they get narrower towards the top.
Oh, the desired frequency range is 30-35Hz with active high pass below that. I'd ideally not want to need to worry about bottoming the drivers easily at these frequencies. Power available will be 125/250(8 and 4 ohms)X 2 class D. I don't listen that loud, but they do get turned up occasionally. Room is 14x22x9' with one small opening and a lot of glass.
Well, as I said, the pic is without the wings. Imagine 1.5 ft wings at 90 degrees on either side of the manifold
Ah, yes. I forgot you had said that.
So, this worked much better than the ripoles you had tried in the past? Were you able to equalize the ripoles to account for the earlier rolloff from shorter path?
Also, you said that the inefficiency of the ripoles caused them to bottom earlier than other open baffles because they needed more power. It would seem that this would be offset by the added mass loading and cone control of the ripole and in the end all the different open baffle bass alignments would have similar max spl capabilities with same drivers and path lengths.
Is that not the case? I've even read people saying that the Ripoles will have high max spl than other non mass loaded open baffles because of the additional cone control. That's assuming the the driver's thermal power handling are still within limits.
It's hard to know what to believe just by reading the internet
I did build a test non optimized ripole using Alpine 10" car subs I had on hand. I can say that they are extremely inefficient, but they did not seem to suffer from easily bottoming out. Connected to one channel of a pro amp 640W@4ohms, I had the gain at 3:00 with the preamp at 12:00 before I started getting decent volume out of it. Those drivers are only about 85db efficient on their own with around 12mm xmax. I think I read that you can lose as much as 10db efficiency in a ripole, does that sound about right to you? Anyways, that was a fun experiment that gave me an idea what to expect. They sounded nice once dialed in a little. I measured a 10db quarterwave peak at around 240Hz that was very audible and annoying, but once that was notched and with a 140Hz xo applied they sounded surprisingly decent
By the way, thanks for the help.