Midrange Advice

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hey everybody,
I'm looking into building my first 3-way system, and I'd like some advice if you'd give it. I've pretty much settled on the Dayton DS270-8 as the bass driver, and I'm thinking I may to with a ribbon in kind of a supertweeter roll. What I'm really not sure on is what direction I want to go with the midrange. Ideally, I'd like the midrange to cover the vast majority of the vocal range, but crossing around 800-1000 Hz is what I've pretty much decided is realistic. Don't really want to go higher than that due to the cone breakup that starts around 1k for the woofer. I'm leaning toward the Dayton RS52AN-8 as the mid, but I have zero experience with dome midranges so I wanted to get some thoughts from those who have experience with three-way designs.

If you have specific suggestions, here's what I'm looking at in terms of design criteria:
Under $45 per driver, at least 50W power handling for the desired frequency band, and preferably with reliable FRD/ZMA data for crossover design.

Thanks everybody!
 

GM

Member
Joined 2003
Historically, for highest speech intelligibility, 125-5000 Hz and for best overall music reproduction [HIFI], 50-11000 Hz, choosing 300 or 500 Hz [depending on bass extension] -5 kHz compression horn as the best overall compromise based on acoustic power distribution.

Well beyond many DIYer's budget, so normally a 4-8" 'FR' driver is used.

GM
 
I've seen those in action over on FR, XRK did the Daytonator mods with them Fortunately, I'd be able to avoid that breakup region crossing somewhere around 4500. The problem I see there is that directivity starts becoming a problem there, losing off-axis response. As far as attenuation, shouldn't be a problem, that 10" woofer is rated at 90.7 dB and the PA130 is only 88.2
 
Wow Mike, that's an impressive build, and exactly the kind of analysis I was looking for on that mid, objective AND subjective. I like the baffleless concept, I may do something similar when I put together this build. The limiting factor I think will be that I'm looking at a 4+ cuft tower for the woofers that I don't want to be much wider than the woofers themselves, so mid and tweeter placement would likely end up too high on top of them. Otherwise, I'll just end up with BSC in the crossover.
I think I failed to mention it, but the plan is for these to be L/R in HT as much as they get used for stereo music. I intend to make them entirely passive and run them off of an AB amp, so no DSP is planned for these.
 
I thought about doing BMRs for the midrange, but the issue is power handling and sensitivity. I am planning on doing a center channel to complement these as well, though, so it may end up being BMRs there.

Also: the HT usage is one of the reasons I'm concerned about directivity, I don't have a "listening position" I have a listening area. It's therefore important to me that everywhere on the couch sounds good.
 
....The limiting factor I think will be that I'm looking at a 4+ cuft tower for the woofers that I don't want to be much wider than the woofers themselves, so mid and tweeter placement would likely end up too high on top of them.

You can mount the RS52AN and the tweeter onto the front panel like what I did with the Scanspeak D7608 Dome Mid.
 
I think 800Hz will be stretching the DA270 (edit: DS270, similar driver) too much. It has a simple motor and the somewhat low breakup of a 10" cone will make the midrange distortion less than ideal to cross at 800Hz. Try to aim around 300-500Hz XO. An RS100 (or two!) should fit nicely between a 10" and a ribbon.
 
Last edited:
GM, I don’t really have the luxury of setting exact parameters for directivity, unfortunately. I don’t own a house and end up moving fairly frequently, so I have general rather than specific goals. In any case, I don’t consider myself an audiophile, but more of a “hifi enthusiast” so I’ll most likely be satisfied with “pretty good.”

TMM, you’re right about the distortion. Unfortunately, PE doesn’t include distortion measurements in their data files, so we have to kinda guess. I went and checked, and the 5” version of that driver is actually the one in my basket. The 4” didn’t quite meet my power handling or sensitivity goals. However, the 4” is available as an 8 ohm with truncated frame, so maybe 2 in parallel... we’re getting out of the goal midrange budget there, though. And then there’s the consideration of having a point source for speech or multiple sources, even if they are close.
 
GM, I don’t really have the luxury of setting exact parameters for directivity, unfortunately.

OK, since listening/viewing [Lp] distance is normally governed by [TV] screen width or off axis viewing angle since many TVs are somewhat limited in this respect, ergo shouldn't change from room to room, so either use this or I guess fall back on the traditional 60/90 x 40 deg. for longer/shorter [Lp] and adjust toe-in, seating to suit.

GM
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.