high-efficiency design mid choices

rjj45

Initial planning/design for a high efficiency design.

Got got some ESS Hiel tweeters last year, and recently got a pair of Dayton PM385 woofers when they were DOTD.
https://www.parts-express.com/dayton-audio-pn395-8-15-neo-series-pro-woofer-with-4-voice-coil-8-ohm--295-044
That's listed as 97dB SPL at 2.83V/m, so lose about 1.5 dB for BSC, and now we're at 95.5 dB 2.83v

Now I need to choose a mid(s).
I'm leaning towards a MTM with 2 FaitalPro 4FE35 each side.
https://www.parts-express.com/faitalpro-4fe35-4-professional-full-range-woofer-8-ohm--294-1124
I like the Neodymium version, but can't see how it's better.
The 4FE35-8 is listed as 91 dB/w, so 2x should give about 97 dB/w (in this case, is that 97 dB 2.83v ?)
But minus 1.5 dB BSC, and we have about 95.5 

Or I could get something like a Beyma 6 inch mid. and do a classic TMW

Any suggestions for "wow that's great" sound quality, low distortion and high efficiency mids?

dcibel

1.5dB BSC?

You're looking in $50-$100ea price range?

jhollander

I like the pro paper mid idea.  I've heard a few of the B & C and I liked them.  I've used the bargain Dayton PK165, and despite the lumpy response it was quite resolving.

rjj45

Yeah, looking to spend about $50-100 per side. 
re: JH - yeah, I've heard good things too. Ready to experience the fun. 
B&C, Beyma and FaitaPro are top of the stack. Reasonable cost, low distortion, and smooth(ish) FR.

dcibel

1.5dB BSC is ok with the woofer at floor level I think. You could go pro, apply no BSC in the crossover, then EQ it into shape in room.

I'd put PM180 on the list, though I wouldn't call this one a pro driver due to limited thermal capacity (small voice coil).

jr@mac

https://www.parts-express.com/lavoce-man06180-6-1-2-neodymium-midrange-woofer-8-ohm--293-713

Wolf

PM180 is a good idea. Could even use the PS180 or the new poly-neo driver PE peddles for car audio.

The difference in the NeFeB vs ferrite is the Neo will be a lower HD driver inherently. Studies have been done.

rjj45

Thanks guys - still mulling over a 4 inch MTM vs a 6 inch mid-woofer,but Hoffman's law is biting me now. Can't find a 6 or 6.5 inch high efficiency driver with lowish bass (50Hz or so).
As far as my ballpark BSC, I figure crossover woofer/mid around 300-400, so half of a 3dB BSC "should" be handled by the woofer, and half by the mid. <shrug> should work.
I'll look at the suggested solutions, and maybe even order a few from PE to listen and test, and send back the losers.

dcibel

In pro world, you'd need to look at 10-12" drivers to achieve anything near 50-60Hz, then look at compression drivers and horns to meet the high frequency demand. For high output designs, I'd skip the 4" midrange idea personally, 6" would me my absolute minimum size. Greater surface area means less excursion for a given SPL. Two 4" drivers is still less surface area than a single 6".

Please don't burden your midrange with those low frequencies. If your crossover is at 300-400Hz, the BSC is covered by the woofer (as it should be) and the demand of your midrange is in the 300-400Hz range, not 50-60Hz. Woofers placed at floor level will have some floor reinforcement and won't need 6dB compensation like a stand mounted bookshelf does.

tajanes

these 
http://www.usspeaker.com/beyma 5MP60n-1.htm 

get close (maybe best to look at ~240+ low for mids) to your stated low range (and re the low end side, down below 300 you are in a very low ear sensitivity range for crossover concerns, and agree with dcibel comment re BSC overlap for woofer duty) and depending how high you're looking to cross to tw...  
  
you could possibly keep the crossover out of the 1500~4500 highest ear sensitivity range...   (and for those concerned about high freq dispersion, could be much, much worse, you could be considering head-in-a-vice $250g electrostats....  ha)
    
and these may be the 6.5's you are looking at ?
http://www.usspeaker.com/beyma 6B30P-1.htm

fyi I have not listened to these, just replying per your post info on stats, and I'm a bit biased towards beyma (good experience with my 12's), and a fan of employing broad range drivers as midrange+.   And fav's are Audio Nirvana's; https://commonsenseaudio.com/an6.5cfspecs.jpg

tajanes

fyi 
here are the 6.5 AN's, as employed in a two way (biamped / active minidsp) clearly capable of 20g Hz (5db verticals, approx 1 meter)

OscarJr

Not cheap, but look into the Beyma mids, is what I would do.  I was thoroughly impressed by the Beyma 10G40 I tested.  Ciare/B&C/Eighteen Sound come in at very close 2nd place within the scope of my testing; with the Beyma 10G40 and the B&C 10PLB76 being the best values for the dollar. 

rjj45

I've been looking at Beymas for a couple of weeks just to mate with the ESS Heil AMT tweeter, and I really like the 6G40ND  - it's reasonably flat, low distortion, good efficiency, just a bit over my budget. But right now it looks like the cream of the crop.
And I will accept the expert advice to forget about bass with this guy. Only with a sub if running TM (which might be the change down the road.)  But I don't really see any other competitors in this class, at this price. ($170)

http://www.usspeaker.com/beyma%206g40nd-1.htm

rjj45

Seems like everybody likes Beymas, and they are reasonably priced.  
Thanks for all the advice, guys. My first foray into this area. 
A friend some years ago had a VOT, and it was a lot of fun, if not exactly flat.
The dynamics were incredible.
I'm hoping that this will have some of those qualities, and better FR and distortion to boot.

rjj45

tajanes said:

fyi 
here are the 6.5 AN's, as employed in a two way (biamped / active minidsp) clearly capable of 20g Hz (5db verticals, approx 1 meter)

Looks great, but way over budget. Thanks for the post.
I'm working right now with a Tangband W4-1320 MTM. Little 4" guy goes out to about 16Khz flat.
Phenomenal full range driver.
Best regards,

rjj45

Gosh, decisions, decisions. The Beyma 6CMV2 actually has 5.7mm xmax compared to 1.0mm xmax for the 6G40ND .
http://www.usspeaker.com/beyma%206CMV2-1.htmhttp://www.usspeaker.com/beyma 6CMV2-1.htm

Wolf

How about PRV? 6MR500-NDY or 5MR450-NDY:

https://www.parts-express.com/Search.aspx?keyword=ndy&sitesearch=true

Dustcap is ugly, but that's easily fixed.

rjj45

Wolf said:

How about PRV? 6MR500-NDY or 5MR450-NDY:

https://www.parts-express.com/Search.aspx?keyword=ndy&sitesearch=true

Dustcap is ugly, but that's easily fixed.

Yep, those do look very nice, and I'll probably order 1 or 2 of them to test and listen to before my final decision. Just send them back to PE if they don't make the cut. Thanks for the input!

Hmm, most of the PRVs have a 5 dB notch between 1k and 2k. That indicates a cone/surround problem, right?
And it would show up in a ZMA plot, correct? 

dynamo

I have never heard one but how about this? I’ve always had good experience with my limited use of Audax products. 

https://www.madisoundspeakerstore.com/pro-sound/audax-pr170m0-6.5-midrange-100db/

dynamo

A pair of 8 ohm 10Fs would net you 93db but you would be stretching it, relying on a little boost from the band pass crossover. I can vouch for this being a very nice little driver.

https://www.madisoundspeakerstore.com/approx-4-midrange/scanspeak-discovery-10f/8424g-4-midrange-8-ohm/

Wolf

Ya know- I don't get the whole 10F bandwagon. I've heard it a few times. Brian's 'reference mini', and PaulK's Cavatinas. It sounds dead to me with no life/realism.

rjj45

I keep coming back to Beyma, and now B&C is in the mix. Not feeling the love, frankly for most of the others - PRV, LaVoce. Maybe try  the Faitalpro 6 inch Neos. 
I'll probably order one of each (and the PM180) from PE and run my own tests. 
I have been noticing that some of the nicest flat FR, low distortion Pro 6" often have 1mm xmax - have to run the models to see if that will be a problem.

dynamo

Wolf said:

Ya know- I don't get the whole 10F bandwagon. I've heard it a few times. Brian's 'reference mini', and PaulK's Cavatinas. It sounds dead to me with no life/realism.

I definitely agree that it is a sound that could be called dead, or perhaps less negatively called sterile or flat. That said though it is also very uncolored and clean. Just depends on what you’re after I suppose.

Sorry for the tangent, back to your regularly scheduled thread. 

OscarJr

rjj45 said:

Gosh, decisions, decisions. The Beyma 6CMV2 actually has 5.7mm xmax compared to 1.0mm xmax for the 6G40ND .
http://www.usspeaker.com/beyma%206CMV2-1.htmhttp://www.usspeaker.com/beyma 6CMV2-1.htm

Keep in mind that many times with the high-power midbass speakers, the Xmax is calculated by the voice coil overhang (and sometimes other factors), but can tell you that sometimes, depending on the actual speaker, you'd be hard pressed to actually get that much excursion and not run risking bending of the cone outer edge.  The surrounds just don't move that much, especially if they are heavily doped with sealer or have a damping compound (Eighteen Sound 10NDA610s and Ciare NDH 10-3 have this).  Take those Xmax numbers with a grain of salt and assume what I call a "safe" Xmax of 65-70%  of what the manufacturer lists.  Don't get me wrong, I'm not saying this is the case with all pro-audio midbass/midranges, some that I tested could easily get to Xmax and more without damage, and others I could tell the cone was a couple of mm away from some buckling.

rjj45

Thanks Oscar, really appreciate your knowledge and experience in this area.
Honestly, I'll need to run the box models before purchases, but I am back with a Faitalpro 4FE35 4 inch MTM on the top of the list. I don't need or want small club volume, just some effortless strong dynamics for home use.
I really like that Faitalpro gives you specs for both xmax and xdamage.

OscarJr

rjj45 said:

Thanks Oscar, really appreciate your knowledge and experience in this area.
Honestly, I'll need to run the box models before purchases, but I am back with a Faitalpro 4FE35 4 inch MTM on the top of the list. I don't need or want small club volume, just some effortless strong dynamics for home use.
I really like that Faitalpro gives you specs for both xmax and xdamage.

From the bunch I tested, the Faital Pro's had the most excursion potential (all three different models).  

The one with the least excursion was the 18 Sound 10NDA610, but that was expected since the listed Xmax is only ~2.5mm.  Like the Ciare NDH 10-3, it has a black, rubbery dampping compound.  The Ciare has it in the valley of the front of the m-roll cloth surround, where as the 10 NDA610 has on on the backside of the m-roll surround, on the underside of the outermost half-roll.

This Ciare I pushed too hard during break-in (even though I was within Xmax), and I think you can see where the cone edge started to slightly buckle.  I ended up putting a very thin fiberglass mesh on the backside along the entire circumference where the crease started to happen for added support, even though they will never see that level of excursion again.  That black damping compound is what limits the excursion quite a bit on this speaker, even though the voice coil overhand is there.


This is the 18 Sound 10NDA610 backside shot.  Looks/feels like the same kind of damping compound.

rjj45

Some interesting updates (for me) in this project.
First, I noticed a comment by Jeff Bagby for someone's pro woofer IE: "nice high QMS".
Then I was reading a Tony Gee design/writeup for the Calpamos:
Quote: " When choosing suitable pro drivers for a domestic hifi loudspeaker there a few parameters that have to be taken into consideration. In regards to ..... midwoofers we are looking for a driver that has low mechanical losses, low moving mass .... Low mechanical losses are important when playing music at low sound levels. If the losses are too high you get a speaker that doesn't "open up" unless it is played loudly.....
One way of checking if a driver has low mechanical losses is to look at the impedance peak at the resonance frequency. If it is low and wide then the driver has high mechanical losses, if it shows a high and narrow, sharp spike, then we are looking at a woofer with low mechanical losses. "
End Quote
TG also mentions a high BL/MMS number for good midrange detail.

 Top of the list:        QMS         BL/MMS     Xmax        Le           Fs Impedance peak
Beyma 3FR30ND    9.5            2.4             4.5mm     .3mH        72
Beyma 4FR40ND    10.8          .93             3.0mm      .2mH       63
Faital Pro 4FE32      4.9           1.23           2.7mm      .18mH     62
B&C      3.5NDF26    8.8           1.27          3.2mm       .26mH     70

Looked at this this way, the Faital Pro 4FE32 doesn't have a Qms to match the other candidates.

JasonP

This is slightly lower sensitivity, but super smooth. I've been listening to it for quite some time now. It's quite nice, IMO. https://www.madisoundspeakerstore.com/approx-5-midrange/scanspeak-15m/4624g-discovery-5.25-midrange/

rjj45

JasonP said:

This is slightly lower sensitivity, but super smooth. I've been listening to it for quite some time now. It's quite nice, IMO. https://www.madisoundspeakerstore.com/approx-5-midrange/scanspeak-15m/4624g-discovery-5.25-midrange/

Thanks. That IS nice, and very reasonably priced also.

OscarJr

I told ya those Spanish bastards are on to something over on that side of the Atlantic! lol

rjj45

OscarJr said:

I told ya those Spanish bastards are on to something over on that side of the Atlantic! lol

Oh, I see. I didn't realize that Beyma was HQed in Valencia, SP. Taking another look at Beyma 5 and 6 inch mids now.