I've been listening to 2 x 1899 in stereo for the past couple days now. I'll need more time to let the drivers fully break in and listen to more material, but I think I can share my initial opinion now and maybe do a follow up a few weeks later. I understand that most of this will be subjective...I'll try my best to not be biased. The best I can really do is compare the 1899 to other speakers that I've heard in the same environment, so I've listed them below. I've also mostly listened to music (jazz, classical, acapella, edm, house, rap, hip hop, punk, rock) and only a few movie scenes. I feel like it's easier to do "critical listening" with music rather than movies. I already knew the 1899 would provide more than enough headroom/volume for even the loudest movie scenes, so I focused on music instead, for this review. That being said, running these full range for some of my favorite movies scenes was pretty great.
Speakers I've experienced in my home:
Curt's Sealed Aviatrix
Part Express RS722
Clearwave Dynamic 4TSE
DIYSG Pure 10
JBL JRX125 ("Pro" speaker, closest to the 1899)
Highs (FL-450 on SEOS 15): Best I've heard in my home. Similar sound to the DNA-205/SEOS 10 combo on my Pure 10's, but more refined. The first time I listened to the Pure 10's, it was a real eye opener. I feel like listening to the 1899 high's took that one step further, hearing even more detail than what I've experienced on the Pure 10's. I feel like the high's on the 1899 may be a touch more laid back than on the Pure 10's, but that may just be because the 1899's have much more of a mid/low presence than the Pure 10's. Compared to the JBL JRX125, the 1899 certainly beats it in every way. The JBL's would go loud, but sounded harsh at all levels for me. I am very pleased with the highs on the 1899 and wouldn't change a thing.
Mids (12" Eminence Deltalite): Best I've heard in my home. I first experienced what really good mids could sound like with the Clearwave Dynamic 4TSE. Something about a dedicated midrange has always stood out for me. The mids on the 1899 are again what I consider "one step better" than the Dynamic 4TSE. It might be the high sensitivity, or the large amount of speaker cone dedicated to the mids, or both, but it sounds phenomenal. Everything in the mid range just "comes alive". I am very pleased with the mids on the 1899 and wouldn't change a thing.
Lows (2 x 18" Eminence Sigma 18A): Best I've heard in my home. I ended up with a tuning somewhere around 35-40Hz. I never really planned to run these full range for any material, as I'll eventually have them crossed over to multiple SI HT-18 drivers. But other than a few dubstep songs that I know dig really deep, the 18's were able to put out everything I had hoped for and more. I know it's been stated in a few places that bwaslo tuned the woofers "hot" in the crossovers, but I'll mentioned here again, there is definitely a native "bass boost" on this speaker. Not a ton, but noticeable. I am a basshead, and I've always felt the need to apply some eq to get a good full low end (on IEM's, large headphones, and speakers). This is the first time I haven't felt the need to apply any eq. It honestly just sounds perfect to me out-of-the box. Just like many other guys on this forum, I've always been on the hunt for that awesome midbass punch/chest kick/dynamic feel that you experience at concerts. This is the first time that I've been able to produce this in my own home. Of course it takes high volume to get there, but cranking 2 of these in stereo is absolutely able to get my lungs/organs moving. It's probably my favorite thing about this speaker so far. It just puts a smile on my face that I can't get rid of. I am very pleased with the lows on the 1899 and wouldn't change a thing.
Different Levels of Volume (I used an UMIK-1 placed around 6-8 ft from both speakers to get an idea of the overall volume level in room):
Low/Medium (50-80dB, C-weighted): For some reason, I had the worry in my mind that these huge drivers wouldn't be able to accurately produce good sound at low levels. I was definitely wrong. They sound great in this range. It almost sounds like it's got Dynamic Volume (A feature on Onkyo receivers I've owned) built in. The bass and mids don't disappear like you would expect at low volume.
Loud (80-110dB, C-weighted): This is where dreams come true. You start to feel the midbass, everything in the room shakes...it sounds like you're 20 ft away from the band at a live concert. I don't think any of the drivers are any where near being stressed at these levels.
Stupid Loud (110-120dB, C-weighted): I wore ear plugs for these levels. I can handle the mids and lows at this level without ear plugs, but the highs are just ear piercing. I did briefly crank it up until REW showed 120dB. I thought maybe I could find the 1899's limits, but I think I just found my own instead. Even as it was just ridiculously loud, I did not hear any major distortion or artifacts. I'm not sure about the CD, but I could see that excursion on the midrange and woofers wasn't reaching dangerous levels yet either. After that experience, I'm pretty sure my Hypex amp would run out of juice before the 1899 would. Needless to say, I won't ever run music that loud again, and even at +5 over reference for movies (I usually listen at reference), I don't think they would quite reach that level either.
Overall, I couldn't be happier with this speaker. It honestly just sounds so much better than anything else I've ever heard. My biggest goal was achieving serious midbass that you can feel, and the 1899's pour it out with like 2-3mm of excursion on the 18's.
Bwaslo, if you ever see this, this is an awesome design and speaker. Thank you for putting in the work and making the plans available to the DIY community.
Erich, as always, thanks for getting the baffles and all of the components together and offering it as a kit. I counted, and we sent a total of 82 e-mails over 8 months LOL. I appreciate your patience and efforts to help me get these built.
I'd really like for more guys to come by and hear these speakers so we can get some more impressions out there. If anyone lives in or is visiting the DFW area, send me a PM and we can set something up. I think BCRSS and I will still try to set up a local GTG sometime in January.
BTW, that's a 70" TV in the pic.
EDIT: At some point, I will lug one of these outside and try to get some good measurements. If I do, I'll post them here.