So... I'm curious. Which drivers - costing twice as much as the RS225, is a significant step-up in performance in your view - and what type of step in performance are we specifically talking about?
I was not really thinking of any particular driver, I was making the point that the RS225 is a great value. But for significantly more money, we could have the Scanspeak 22W/2851T revelator woofer... The Satori W024P and W024TX also come to mind. The W024 is often presented as nearly a 10" woofer, but it has an Sd of 255 cm^2, which makes it more of a extra-large 8" woofer. The W024P is about 2x the price of the dayton. The other options I mentioned are more like 3x to 4x the price.
But since you opted for the 10" RS270, those comparisons are kind of moot. The RS270 is on sale at PE now for $92, which makes it an even better value.
Another excellent 10" driver is the SB Acoustics SB29NRX75-6. Unless you have an OEM account, it's CA$245 from Solen, which translates to about US$180. It's pricier but also more robust & capable of higher output, probably lower bass. P-P excursion is 22mm. I use 2 of these for an LX521 inspired push-pull OB "W" frame config. The bass performance is tops. About the only downside is that the overall diameter is oversize for a 10": 290mm vs 272mm for the RS270.
And I was just trying to understand what people mostly hope to achieve, when buying more expensive drivers.
Sometimes the better driver can take more beating, more power, play in smaller cabs or cross higher and relieve you from complex cross-overs. But to me, it seems to be an often exponential curve, when it comes to price/performance.
I have tried to simply put different cabinets next to each other together with a friend, with different drivers and speak-on and active filters in front. Making it possible to switch rather quickly between them.
The experiment was to try how they performed between around 50 to 500Hz, in a 3 way with added subwoofers - meaning - no need for high excursion sub-frequencies and no need for fine detailed midrange abilities.
The room is well damped, good amplifiers, fully DSP controlled and everything measured to be equally smooth.
2 x Satori W24P
2 x RS225
2 x SB23NRX
2 x Purifi 6,5 PPT6.5W08
The Purifi lost around 12 dB overall to flatten them enough in a close box, to play as deep as the others - which of course is not optimal. But they did prove to be more smooth in the top against the SB's, which made everything measure much better. And they can take a lot of power, which I easily have, since my system is a rather powerful active one.
In bass.... it really seems to be a matter of SD... moving air. The very fine detail of the more expensive drivers seems to fade out easily in the overall performance.
It also seems that cabinet construction and a keen eye on any interference with surrounding walls and general acoustics, play a major role when trying to get a perspective on these test'.
So in the end, I agree that the RS225 wins throughout. It looks good, does everything you ask from it, and the price is fair. You could pay way more.... but get what? I could mostly hear the difference between the SB23NRX and the Purifi in the 150-600Hz range. The Purifi lacks bass/SD, but has a much clearer mid-woofer voice presentation. I could EQ the SB a bit to come closer... but it never reaches the same refinement.
My point is, that it's quite important to understand what we pay more to get. Sometimes the extra price, does not give us what we actually need, and time/effort/money is better used elsewhere.
I often look at both Kii3 and Dutch Dutch 8C... because they are so highly looked after, when it comes to overall excellent performance and measurements. They both use off the shelf Seas Prestige tweeters. The real difference seems to be the EQ, cross-over and cabinet design.
Not to forget that the price obviously goes WAY up, when a given driver is sold in low numbers, compared to the ones spit out in the thousands.
Don't forget that you also pay for a fancy finish.
I have been involved in ordering custom drivers, and the price goes up very quickly to make a driver look pretty.
Which is great, we also want things to look nice, but it obviously isn't beneficial on an acoustic level at all.
Also you pay a very high price for drivers when they have to do low end AS WELL as midrange at the same time (midrange being >100Hz). One way of improving IMD is going to town with a perfect motor design. Getting the best BL(x), Kms(x) and Le(x). Which is tricky and often results in expensive drivers.
Or you just filter your midwoofer and let the low end being done by a bunch of subwoofer across the room.
IMD will go down drastically, since there is basically no intermodulation going on anymore for the midrange/midwoofer, because there is no cone excursion.
This can be seen very clearly at some measurements Eric has done with his Klippel system.
Since amplification and active filtering is so cheap these days, I see very little benefits in letting one woofer doing low end as well at midrange all at once. Especially having to pay a much higher price for it.
Only when there are no budget constraints. Sure, why not.
But in an high end setup with no compromises, you need a multi-sub system anyway
BTW, I can't disclose actual prices, but having experience with OEM myself. Quite a lot of prices are already 3 to sometimes 5 times lower than consumer prices. Starting from just 100 pcs MOQ.
Which brings some "high end prices" down to just your average speaker price.
BTW, Dutch & Dutch also use a pretty simple Seas woofers and Wavecor subs.
They definitely don't perform the best in distortion, yet nobody seems to care about that.
I agree that the SB29NRX75-6 is a great 10" woofer. But it is way outside of my budget. The driver budget for the original project was $250/side for drivers. When I opted for a 10" woofer, I allowed the budget to grow by 10% to $275. I am currently at $263/side with my final driver selection, based on September Madisound prices.
https://www.diyaudio.com/community/threads/compact-low-cost-active-3-way-speaker.402812/post-7455272
Since you plan on bi-amping the woofer I think you could get away with an 8 ohm driver. Madison has the SB29NRX75-8 on sale. It is $24.00 more than the Dayton so it pushes your driver cost to $287.00, close to your target.
https://www.madisoundspeakerstore.com/approx-10-woofers/sb-acoustics-sb29nrx75-8-10-woofer-8-ohm/
https://www.madisoundspeakerstore.com/approx-10-woofers/sb-acoustics-sb29nrx75-8-10-woofer-8-ohm/
Example of "compact" studio monitor with 10" woofer. The Dynaudio bm15a goes back a couple decades (in passive version) but the active version is still offered today.
Thanks for the suggestion.
My budget is not based on what I can afford, or what I would be willing to spend... The budget is based on what I think my friends/relatives would be willing to spend... The budget of 250 +10% = 275 is for the every-day retail price of drivers, not a sale price.
yeah... I should probably start calling this a "full range 3-way compact speaker" to emphasize that it is compact in comparison to other full range 3-way speakers.
However, in terms of naming, I am having a hard time integrating the phrase "full range" and "3-way" into a good acronym... for now, my working name is LCCAM - Low Cost Compact Active Monitor. If anyone has a good idea for a name that encompasses low cost, full range, 3-way, compact, I would be interested...
j.
That is an interesting speaker.
Based on the external dimensions, I think the internal volume is about 36 liter. The frequency response is rated at 40-22k +/- 3 dB, which suggests that at 40 Hz the response will be -3 dB, but it could possibly be as much as -6 dB down at 40 Hz.
My neighbor/friend Jamie, touring drummer for Tears for Fears, uses them in his tiny studio. They are meant for nearfield, but even from 8-10' away, the bass is subjectively very impressive. Factor in room gain & I think it goes another 10 Hz lower than spec. I built the speaker stands for him out of scrap live-edge 2" thick fir planks. Maybe the 4' wide 6' stack of 8" thick cotton batting insulation behind the speakers/console also helps.
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got it, trying to strategically spread the virus. smart, smart!
Too bad Dynaudio tweeters never had a good protection grill. They never perform well, dented like the one on the left. 🙁
I agree that Sd and Vd are probably the single most important factors in performance up to ~ 150 Hz. In my main system, I have changed the mid and tweeter several times, but the original SB34NRX75-6 woofers in the original 70 liter sealed boxes remain constant. When used below 250 Hz, these woofer boxes are so musically satisfying and have such high SPL capability, I have never wanted more performance. There are other 12" drivers which have better performance on paper, but changing out my woofers is very low priority for me.
I believe that odd-order harmonic distortion and modulation distortion in the range from 50 Hz - 200 Hz can muddy up the sound, but I don't have a real feel for how much is too much... So once we have enough Sd and Vd, other factors might become important.
I also feel that of all the "woofer in a box" architectures, a sealed box design with LT EQ and possibly room correction EQ provides the most natural and realistic bass performance. It does not provide the highest SPL, and it is wasteful of amp power, but it sounds the best. I am excluding open baffle designs or infinite baffle (wall mounted) designs when I say "woofer in a box".
Someday I would like to hear a cardioid bass system... Technically these are a woofer in a box, but they combine elements of open baffle design.
j.
That depends, a passive cardiod system isn't and is technically more close to a dipole/open baffle.
I see absolutely zero benefits for having a cardioid system for the low end.
The exception being seriously big sound reinforcement systems and venues.
An active cardioid system (made with closed boxes or even with BR, or anything else you want) is basically just a multi-sub system anyway.
The only downside of a closed system for low-end is the additional 2nd order distortion because of the asymmetrical compliance on the woofer. That's about it.
Which I think is a lot less of a compromise than the insane loss in SPL with a dipole/ passieve cardioid system.
Which btw, introduces quite a lot of distortion (because of more cone excursion + power), but it also doesn't fix these pesky room modes entirely.
This is even true for mid-range performance.
Although the downside is that bigger woofers naturally beam more = higher directivity.
Also the box size will be obviously much bigger.
So a good compromise is something like a 8 inch as a passive cardiode for mid-range or ideally 10 inch (maybe 12), to get a better performance around 100-200Hz. This is also the area where the D&D 8C suffers btw (you can see the distortion going up in that area)
If you just calculate the theoretical SPL from an open baffle point of view (which a passive cardiod is), you also see immediately why that is.
A 2nd decent option would be just a active cardioid system for midrange with like two 6,5 woofers back-to-back.
A bit fiddly to setup and get right, but certainly not impossible.
If you can make the enclosure small enough, it's also extremely easy to get standing waves inside the cabinet under control.
As long as there isn't much cone excursion (ideally below 1.2-2mm) you can make it almost as small as you want and just correct it with active filters (to a certain extend obviously).