RS 3-Way Vs. Adire 2641, 641, or LCR????

[havix]

Hi everyone, long time lurker and first post. Something that I've been really going back and forth on is whether to do an Exodus kit or do the Dayton RS 3-way. This is a tough decision since both look like excellent designs. Just from a quick glance I would assume I would get higher output and a lower frequency response with the Exodus kits. Any opinions on this?

[JonMarsh]

What Exodus kit and what (who's?) RS three way?

The Exodus kits are based on the Adire Extremis midwoofer, which does have very long throw (Xmax), but also rather low efficiency. In the lower bass, where a system would be Xmax limited, the Exodus will certainly put out more bottem end than, say, a system built as a three way with dual RS180's on the bottom. OTOH, something like Dawaro's TMWW with dual RS225's would match it in output level and distortion, require a larger box, but only need about half the amplifier power...

There's no getting around Hoffman's Iron law. Amplifier power is relatively cheap, so perhaps the smaller speaker size using the Extremis is atractive- the kit pricing is reasonable, considering that buying the Extremis drivers "standalone" is way more expensive than an RS180 or RS225.

My only comment on the Exodus LF design is that a 3" port is OK for a single moderate throw 8" (5-7 mm Xmax) or dual 7" with moderate throw; for the Extremis port airp speed if it's used at maximum throw may be an issue- would be worth looking at with Unibox. For Dual 8's I usually recommend 4" ports, and here Exodus is claing the Extremis is equivalent in bass output to a 10" woofer.

Take a look at CJD's design or the implementations for DAWARO's center channel and tower versions- things to consider. We're not selling anything here, so it's up to you- in either case you need to be able to build up the cabinets, and wire up crossovers on your own- (Exodus doesn't supply built crossover boards, just a kit of parts).

Have fun and good luck which ever way you decide to go. You'll probably enjoy your finished speakers quite a bit, and should have some fun in the process.

~Jon

[havix]

Thanks Jon for the info. You're right that the 3'' port does look like it might cause some port noise at high volumes. The 261 looks the most appealing since I could use the prebuilt PE 1.0 cubic foot boxes. This means that my expensive...much better then comparable commercial speakers, won't look like a high school project. The last set of speakers I built was the Dayton D3's designed by Wayne and I was quite pleased with the sound I achieved. As far as amp power that shouldn't be a problem. If anyone has any direct listening comparisons I would love to hear what you have to say also. Also anyone have an idea how much the TMWW costs, which is also a large factor in this? Thanks again Jon

[cjd]

I got to hear one of Jim Salk's Extremis MTM offerings (with ribbon tweeter) Saturday. Bass extension was very respectable. It felt very soft to me - probably because of the cone material. Very easy going, very laid back sound. I thought a poor match with the ribbon tweeter.

The thing is, the Extremis still needs a big cabinet to really shine, and at that point I start to wonder if a larger driver would provide better results, especially if you're talking 3-way.

I preferred Jim's 3-ways with the 10" TC sounds driver by leaps and bounds - though, of course, that's not really a fair comparison because there are really so many differences. But not that much difference in floor space required. It's all about picking which trade-offs you prefer.

And, you ask about the cost on a TMWW - which TMWW? 3-ways are inherently more expensive - aside from the extra driver(s) you have twice the crossover, and the crossover uses much larger value components.

C

[JonMarsh]

How much the TMWW built using RS28a, RS150, and dual RS225 would depend partly on the crossover you use- there are three or four designs posted on the thread, which vary in component count, as a result of crossover order- the more you suppress out of band stuff, the easier the driver works and usually the lower the distortion, but of course, it affects price.

The RS225's are $40.80 each in 4+, the RS150 is $28.55 in singles, and the RS28a is about $47 each, so for the three ways, all four drivers would come to ~$160, which leaves a lot of money for crossover parts- compares pretty well with $400 for the Exodus 2640.

The Exodus 261 is a two way design; it will play louder in the deep bass than a Modula MTM, but only by about 3-4 dB. There are Modula MTM designs posted for both the Seas and Dayton tweeters. There's also the Natalie P MTM using the Dayton Drivers. Driver cost is is ~ 30 for the midwoofers (on special at the moment for $27), and the tweeter is the ~30 (Seas) or $47 (RS28a). So, you're looking at about $110 per cabinet plus crossover costs (depends on which design you chose).

BTW, the Extremis does not have the stunning lead in distortion that you might expect at moderately loud levels- in fact, at SPL's you'll usually be listening at, MarkK's tests show the RS180 gives it a very good run for the money, and has lower high order harmonics in the distortion spectrum.

I don't sell either; I sugggest you research on the web, and try to find some guys local to you that have built systems with these drivers and listen for your self.

BTW, if you do want to go the Extremis route, I have 8 of them brand new, and will sell them at half the current Adire retail price. I think a three way with the Extremis may be a better design choice than a two way, though the latter can be made to work- check out GrahmT's Extremis MT thread and details- we designed a high order crossover for the tweeters that worked pretty well. Just a lot of parts, again.

~Jon

[Brian Bunge]

Jon,

Aren't all the TMWW designs that all of you posted strictly for the center channel cabinet? It was my understanding that they were all arrived at by using the measurements that Dennis Murphy posted. Is this correct?

[cjd]

Jon,

Aren't all the TMWW designs that all of you posted strictly for the center channel cabinet? It was my understanding that they were all arrived at by using the measurements that Dennis Murphy posted. Is this correct?

Yup - they're all using measurements Dennis took of the horizontal cabinet layout. That doesn't mean center channel, it just means horizontal cabinet.

Life has intruded and the vertical setup/measurements are in a holding pattern till life lands again and there's some room to breathe. Or so I've heard.

But the basic componentry will not change that significantly - it will be small tweaks most likely, not big ones.

C

[havix]

I'm sorry everyone, I meant to say the 641s. No matter. What I like about the adire kits is that I should be able to get equal lower output from one 6.5 instead of 2. This makes the speaker smaller and easier to build. Also I like the idea of 6.5 drivers because the lower bass doesn't have to be generated by 8'' or 10'' woofers. This also means the crossover doesn't have to be built from so many large capacitors making it all the more complicated. If one of the dayton 3-ways was thought to be superior to the 641 then it might make the choice easier.

[cjd]

You will need tos pend more on amplification with the really low sensitivity of the Extremis. And you will still be limited on the total maximum SPL. It's a game of displacement - smaller diameter = more excursion to reach the same SPL.

It does not make the speaker any smaller really - the Extremis needs lots of volume to get maximum low frequency response - just like 8" drivers (like the Daytons).

And it does not change the crossover significantly per se - in this case, it may just because they have chosen to do that. It is a different kind of compromise. In the end, you may have a little savings but I'm not convinced you would have a lot. And when you consider driver cost, it really becomes a wash if not tipping the scales in the favor of the RS stuff.

If you want a "simpler" product to compare to in the Dayton RS line, check out the speakers Paul just finished here.

In the end, we can't make the decision for you. The design philosophies many here hold probably would have most of us gravitate to the Dayton components I suspect - I mean, look at how many designs use those as compared to the Extremis.

C