u/HotPhilosophy8521

My second and far more sane build. I had the tweeter overdamped at first, electrically. Then the box overdamped with denim. Chased those both back and now it's a great sounding speaker. Port is tuned in the 40's, the sub is strictly on LFE duty. Will re=consider the sub (and surrounding cabinet) long term if these stay up on the wall.

LR4 crossover around 2khz. Cabinet is very stiff (acacia and 3/4" birch ply) but still a little back-wall resonance that I need to insulate against a little better I think. Currently has some silicone foam pad but that's doing a great job of vibration damping it's not doing much to kill the sound wave bounce back. 2 walls have 1.5" denim (was five walls but it was killing the midrange spoken vocals).

Maybe 2x 12's in sealed boxes. Maybe a different cabinet to fix the r/tvtoohigh.

RSS390HF-4 15" driver, RSS460-PR 18" radiator, SPA500 amp. 4ft^(3) box.

I'm building a shelf now so my gear isn't hanging off the hearth (also need to pick up four more of the right bolts). Haven't put an SPL meter in the room yet, but it hits.

Klipsch KT-LCRs for mains while I tweak a few things on my earlier mains build. RX-V6A crossing everything down to the sub at 80hz.

Box detail:
11/16" acacia, plus 3/4" birch ply behind the front baffle. Single window brace between the driver/pr, four outside corners braced with 1" strips of birch ply glued and screwed, front and rear baffles doweled. 1/4-20 bolts into t-nuts for the mounts. Amp is in it's own sealed .5 ft^(3) box in the rear (4.6 ft^(3) total volume of the box with the amp and bracing). 1.5" denim lined on five walls (3m spray adhesive). Minwax ebony > gloss poly > matte poly.

Apologies to Henry Kloss for being a rank amateur cribbing from his 1968 design. These are super traditional "east coast" sealed monsters. Sound stage is good, lobing is a thing but not a big thing. Just certain frequencies come in slightly stronger/weaker if you change seats, nothing like a full cancel or shout. Tweet is padded just a bit due to 4 ohm.

Dayton Audio drivers:
RST28F-4 (1-1/8" fabric)
RS100-4 x1, RS100-8 x1, in series (4" x2 aluminum)
(yes that is a 12 ohm net mid, the 8 ohm produces more SPL, they are close enough to mathmatically single point up to ~1800hz but that does leave some soft/louder spots in the 2000hz range)
RSS315HF-8 (12" aluminum)

Fabric highs soften the overall tone against the tinny nature of the aluminum cones. I was originally wanting to cross over around 800hz and 2200hz leaving an easy job for the 4's, but ended up closer to 300hz and 2600hz in the end crossover to find a nice modeling balance in VituixCAD. REW is showing the modeling to be about right. Have a slight imbalance in sensitivity (left louder, right softer) likely due to my amateur solder work. Cabinet is fairly dead but I do have a few loose wires to chase down from rattling in the 100hz-300hz range. Not major but noticeable.

All crossovers Jantzen air core (should have gone iron core for the woofer, paying an impedance price there too), all caps Bevenbi except the woofer zobel which is Solen. All resistors Dayton Audio.

I'm getting close to a really good speaker here. Lots of lessons learned, lots of "oh, that's why they *don't* do this now" experiences. But it's all good. I have a great sound, good to great staging, and enough 2.0 brute force that no sub is needed.

Amps are Outlaw M200 monoblocks I got from eBay cheap. Receiver is an RX-V6A which pushed them fine but was running harder than would probably be good for it long term. Much happier with the big guys pushing those woofers.

(house is old, fireplace was a cheap flipper f'up, is sealed off outside and needs removed from inside, but... old house chores never end. at least they used .75" plywood behind that ugly brick and it's a pleasure to hang stuff from)

tl;dr - My in-room is worse than my VituixCAD by a lot, ordering lpad and zobel parts to help, but looking for experience to point out my many follies.

---- the saga so far ----

Hi folks - I have been a casual audio geek for 30-40 years, used to compete in dB drags (in the 90's). After living the soundbar life I decided I wanted to build a large 2.0 system that could provide big sound and low end extension without needing a sub.

My thought path:

"CV but make it better in the mids" ...then
"JBL L100 Classic but make it tight" ...then
"KLH Model Five but make the '68 dual-horizontal-mid design because it's weird"

I ended up on that last mark, and have built a KLH Model Five horizontal-mid tribute. I will deal with the lobing (so far it's not my biggest problem). Also thinking about wiring them up like a Polk SDA system in the future maybe.

So, design brief:
-- Large bookshelf
-- Massive woofer
-- Double small-ish mids spaced tightly to act as one point
-- A nice tweeter to round out the build
-- Sealed box (50 liter woofer, 2 liter mids, tweeter sealed back)
-- Wall hanging (no port issues/wall gain)
-- Ok with low efficiency, driving with a 100w+ A/B amp in stereo mode

Drivers I purchased:
-- Dayton Audio Reference 12" HF 8 ohm - RSS315FHA-8
-- Dayton Audio Reference 4" Paper 4 ohm - RS100P-4 (x2, in series for nominal/notional 8 ohm)
-- Dayton Audio Reference 1-1/8" Soft dome 4 ohm - RST28F-4 (sensitivity and impedance mismatch, I know)

My crossover values were done with "back of envelope" math then modeled in VituixCAD and they looked pretty ok. Something I thought I could live with.

-- 12mH coil, 40uF cap - Woofer
-- 12mH coil, 56uF cap - Mid high-pass
-- 1mH coil, 4.3uF cap - Mid low-pass
-- 1.2mH coil, 4.3uF cap, series 6ohm resistor (half a pad) - Tweet high-pass

And I bought and built this. Soldered up on a perfboard. Tests out ok, my solder is ugly but the top of the board is pretty enough.

---- and so now today ----

Attached the following pics:
-- middle-of-room 1w/1m test
-- on-wall 1w/1m test
-- VituixCAD as built
-- VituixCAD with suggested fixed padding and zobel add (ordered, not here yet)

They sound good where they're hitting. Sub-80hz is delightful, mid-bass is completely buried. Voices sound good (but sometimes canned), all strings (guitar, piano, etc) and drums are muted to a concerning amount.

Amp in-room is a Yamaha RX-V6A in 2-ch direct mode (YPAO off for testing). It is pretty ok driving them at -30dB or lower for average TV listening. And will shake the building at -20dB.
The amp in mid-room/bench testing was a Fosi BL20a (that little Class D could not touch that woofer).

Looking forward to any input. I realized from the start that the horizontal mids were a "bad idea". That is part of why I built these, I wanted to see what it did. Also I don't think it's causing my larger issues. If I swap in a 4-ohm resistor for one driver the charts look basically identical.

I knew in theory that I had a sensitivity mismatch. I didn't realize how extreme it would be in the build. Also was surprised by the woofer peakiness, when I was building and testing standalone subs for car-fi I never really ran into zobel issues (and I was a sealed box guy then, I like the sealed sound).

I've basically build a pretty good passive sub (that needs some shaping) with a loud tweeter and a complete ugly mess in the midrange. I suspect my crossover math, and I've got hope that the lpad and zobel parts on order will help.

Experience and advice welcome. Laughter at my hubris expected.