Looks really good

Wow, really nice.


Now I know you didn't do it, but could you let us know, theoretically if you were to do it, how you would go about it?  Making those speakers, I mean.

Round 2

So, the OS:MT is a little speaker that I really like. I usually listen to it in the near-field and it sounds a lot different in a bigger space like this. Here's the plot according to Carmody and then my own comparison:






It's amazing how different these speakers sound tonally. Just from listening to sine sweeps you can tell the tonal differences.

I don't have PEQ, but I do have tone controls. Here's that for each speaker.




All of these plots match very well with my subjective impressions. The BK-12's horn couples with the floor to strengthen bass response big time. The OS's downward slope from 2k to 4k makes vocals seemed recessed. I find that the OS needs to be listened to on-axis in this space or else it loses focus. Carmody says that he voiced this loudspeaker with a subtle upper midrange and treble dip (for near-field listening) although it doesn't show up so much in the plots. My ears tell me it's definitely there. In a direct comparison, the BK12 can sound sibilant while the OS is never fatiguing but still has good presence.

So a question for you guys, do the bumps at ~125 and ~250 look to be room modes, or is it the horn resonances as was found in BK16? Because they're definitely there for the OS too. I think purrin mentioned comb filtering somewhere earlier in this thread, but I'm not sure how much that applies to this system. I'd like to do a cabinet simulation like Arnaud did to figure it out this cabinet's acoustic impedance characteristics.

Overall, the OS is more neutral tonally. I think it has more to do with its conventional design more than anything. Has really nice bass for such a small speaker and is totally non-fatiguing. If you want to compare it to a headphone, it's either the HD650 or LCD2 (without the veil). OTOH the BK12 is super fast and dynamic and articulate. There's something to be said for efficiency and what it gives "speed" as they say. On my 2220, I sat around 12oclock for 87dB of pink noise. For the OS, I was at full gain for 86dB. There's always the trade off between size/efficiency/bass response. The BK12 is probably best compared to a Grado that is tuned for extra bass. I hesitate to make that comparison because of the stigma and because it's not nearly as fatiguing as a Grado. I like it though.

Thanks for reading. Let's keep this thread going. 

@Tari
Maybe I'm not getting the cut of your jib, but here's the hybrid album of when I built the BK12 and the hi-fi rack. $50 of ply from Home Depot for the cabinet (and I had plenty extra). Madisound sells the pre-cut cabinet which is a better idea if you don't have the tools or experience to make the cuts yourself. You would just need to glue and screw. Here's the imgur album.
http://imgur.com/a/YuZaj
This was during winter break I think. And this is pre-Tung Oil + Gloss. The Tung Oil gives it a much richer tone that you see now.

@purrin
Yep, those horn measurements will be next. I did desk and nearfield measurements for the OS today. Also measured the OS's port output, which wasn't very fruitful. I'll try placing the mic closer next time or maybe measuring in an open space like JA does. Seeing as how this is the full-range horn club, I won't bother posting any more of the OS plots unless you guys want them.

I'm interested to see how you integrate the Cicadas into your system. They look to have some particularly bad treble nasties according to the Stereophile measurements. Are you going to try to go the purist route again and work 'em without a xover?

Also with regards to the measurements, REW help section mentions that LF measurements are best taken with the mic tilted vertically upwards. Why is this? Am I plotting even poorer bass response if it's horizontal? Thanks again.