Lowthers midrange: how do they compare?


I realize Lowthers aren't very popular here. A quick search returned threads from 10 years ago, and 3 from 2012/2013 asking for pointers to repairs...

Still I'd like to try and ask since my question isn't geared at them being used as fullrangers but instead as midranges. How do they sound compared to the better dedicated midarnges you have heard? I'm thinking of using them in an active system, from 300 to 2000Hz (where I understand they cross to their wheezer cone).

Their sensitivity and 15 ohm impedance is great for SETs. Their price is very high compared to most midranges so not a trivial decission. The "Lowther shout" seems to be above 2kHz. I read they are very fast and detailed, dynamic, and able to retrieve details buried in the music, all while being musical. But would like to hear from anybody who has experienced them.

Thank you!
lewinskih01
" I read they are very fast and detailed, dynamic, and able to retrieve details buried in the music, all while being musical"

They are all of that and very 3d as well if matched with a good single ended amp. I've been listening to them for 15+ years & although occasionally temped to try something else, don't because they are that good. Another thing they do well is produce a wide deep very convincing sound stage. I've never heard this so called "shout" but have read that before. Not sure what that is. The downside of them is they are bass shy and will sound terrible with a mid-fi amp. I've been running a sub with them and good single ended amps which have alleviated those issues. 
If you are bulding try to find the Seas Excel 4.5" or 7" magnesium-cone with copper phase plug mid range driver that Joseph RM33 audio use. It measures really well. Linkwitz tested the 7" one and it performs well all round. Trust me you dont want that piece of whizzer cone flapping around if you dont actually need it.
If you are going to use it as a mid-range, see if you can find a modified Lowther like the ones Horning uses, which have the whizzer removed.  I have a pair of Hornings, and I've never heard them shout ;-)
@shadorne 

Yes, I'm building. I looked into those but their sensitivity, at 88dB @1W, is too low for SETs. Also lowinsh impedance for SETs. Doing MTM and connecting the two midranges in series would fix this, but would be expensive and the tweeter is large and lobbing issues are liekly to show up.
Talk to Brian Charney of Charney Audio about Lowthers.  He uses them in many of his offerings.  Disclaimer: I own his Concertos.
Sounds like you want a midrange not a full range or wide band those are best used fullrange or whats the point since better options exist if wanting to go multiway with crossover on mids. Full ranges are best run full or maybe with a bass system and tweeter added while no networks used on fullrange. I've built 100s of loudspeakers using most all available full ranges there is something there worth pursuing to some degree depending on what your designs end goal is something you dont mention.
@johnk 
Indeed, I want a midrange. Sure I haven't gone into explaining goals as not many DIYs come here. But saying I'm building an active system, midrange driven by a 2A3 SET, and running 300 to 2000Hz...should tell an experienced builder quite a lot. And I've also focused on direct radiators.

So what are the better options, suited for 2A3 amps? Sensitivity of 97+ dB at 2.83V, at least 12 ohm drivers naturally preferred.

So far have not come across such a midrange. Some pro drivers get close, but their 300 or 400W ratings...make me wonder. MTM with midranges in series could do it. If fact something I will be experimenting with to better understand the audibility of lobbing (caused by a very large AMT tweeter).
 Run a compression driver as a mid.                                                         Or a  http://www.usspeaker.com/beyma%20tpl1200h-1.htm for a 2 way   
 Also a SEAS x2 does most of what you ask and mates well with RAAL ribbons and Mundorf AMT. Honestly I think you should rethink most all of what your trying to do. K.I.S.S. is best in loudspeaker design. A tri amped dissimilar driver different radiation pattern loudspeaker will be a can of worms.  
@johnk 

That Beyma tweeter is a great idea. So much so that's the tweeter I'very chosen. Actually it's the TPL150H instead of the 200. That is why the Seas aren't a good match: their sensitivity is way too low compared with the 102dB of the TPL vs 85dB for the Seas. Otherwise they would be great.