Seas ER18RNX vs Wavecor Midwoofer? which one to go with?

Well, there's a lot of 6.5" drivers about, but the SEAS ER18RNX is as good as they get, IMO. It even seems to have a vented magnet. Which is nice...:cool:

You're looking at 15-20 Litres reflex here, and a notch around 4.8kHz on the bass filter to tame that peak.

Couple of designs to give you a clue:
"STARLING" (Seas 27TDFC + Seas ER18RNX) Bookshelf by AmpsLab
The Seas ER18DXT ported two way

I'd quite fancy it with this SEAS 22TFF and a 3kHz crossover circuit a bit like below, where the red resistor adjusts treble level. The notch is possibly set a tidge high at 5kHz, but who cares, it's near enough. :)


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I used 2.5Khz as per Mark K's version (However I used no BSC & a different tweeter)
The Seas ER18DXT ported two way
To me the timbre of of the ER18RNX is more natural than the Wavecor, but it depends on how you implement BSC, I used none so the sound is 'analytical'. The Wavecor sounds a little heavy in the mid-bass.
To me, the Seas CA18RLY has a more natural timbre & better bass extension than both, but again a larger box. This is the one I used with the 22TFF.
infact im getting the same cones from the same oems who gave it to seas er18rnx but this time we are getting the rubber surround with the width of 15mm to go deeper bass like scanspeak 8545... i believe that will have impact even on the upper frequencies as well as it might sound a bit bold but i think reed cones will have thin bass with small roll surround...
Hi Pete ive even checked the videos on net regarding the zaph audio sr71 which uses the same one and i feel its much more uncolored sound through er18rnx than the bifrost even people who have used reed cones has experienced very good resolution in the midrange not as much as the dome mid range though but they are very good but somehow I didnt like the dome midrange sonic qualities I think thats why the dome midranges are disappeared in the market.

even vifa ne was a better driver for mid range performance but i really suspect it bass abilities.
Andy, it's important to realise that ALL SPEAKERS are a compromise, and nothing is more compromised than a two way. :D

Deeper bass fights with efficiency. A good bass speaker has a loose surround. A good midrange has a rigid surround. :confused:

If you are serious about a good loudspeaker that goes loud without effort you probably want a 3 way Troels design:
3-Way Classic

Meanwhile, the SEAS ER18RNX is a decent woofer. Easy to filter. Add it to a decent dome and you've got a player. You might, of course, try a cone tweeter on a third order filter:
TW 70 - 8 Ohm

It's up to you.