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Hi, I thought I'd post an overview of my loungeroom system now its approaching completeness in it's current form. Portions of this have been documented in the DIY section here and other sites and forums, but here it is as a whole system. The overall plan for this system has been a simple active two way with horn/waveguide HF section, taking on board ideas from both the "Econowave" project and a nod towards those older big American speakers with horns & 15" bass drivers, like Klipsch, Altec, etc. But using a modern active DSP crossover, and mostly digital sources. I've also just been switching amps and other parts in and out for fun, buying random DIY boards from the internet if I read an interesting thread, etc. I tried two other waveguides before settling on the current one. It's not particularly high end, there are a few rough edges I need to refine, but it is probably unique and I like the sound. HF section. 1.4" compression driver and waveguide, FaitalPro HF144 with 18Sound XT1464. I've got this just sitting on the woofer enclosure, for ease of trying different waveguides. The compression driver is propped on a small wooden box that holds the LPAD resistors (7dB attenuation on the HF) and protection capacitor. JLH 1969 8watt Class A stereo amplifer. These are usually 10W but I am running it at a lower voltage. This is a very simple build from a Chinese kit, using a switched mode power supply, and the enclosure is re-cycled from an old Korean amp. This is the "winter" amp, during summer I was most recently using a $6 15W TDA7297 chipamp. Crossover frequency is currently 600Hz (or was it 550?). LF Section. 15" LorantzC390X B1 Australian made bass drivers. I was checking out all sorts of US, UK, Italian and Spanish drivers.. but ended up with one made in Dandenong. These are in 140 litre pine plywood bass reflex enclosures. Drivers second hand from ebay. ConnexElectronics TA3020 V3c "Tripath" Class T amp module. In a very industrial steel PSU case as enclosure, powered with a 500VA 35v-0-35v transformer, the highest voltage this can run at without needing a cooling fan. Approximately 110W/channel. I've attached a bit of stained pine to the front to cover most of the industrial steel ugliness. Crossover & Sources. MiniDSP 2x4 crossover plus miniDIGI daughterboard, with OPA2134 opamps on the output as the miniDSP is too quiet to drive most of the amplifiers I try. This is all mounted in a rough and ready pine enclosure, with a "fine" (miniDSP software) volume control and a "master" (ganged stepped attenuator for the opamp stage) volume control. There is an analogue "guest" input on the front panel for visitors to plug in their DJ mixers/laptops/etc into, but the main sources are all optical SP/DIF. Powered by a Jaycar kit linear power supply. Input selection: optical sources selected with a mechanical optical 4 way switch, an AC-1597 from Jaycar. Main source: a "home theatre" PC running Xubuntu Linux 14.04, with an Intel i3-2100t CPU on an Intel motherboard, Antec ISK-300 case, and an SSD. The problematic Antec PSU replaced with a PicoPSU. I mostly play .flac files streamed via NFS using the Linux "clementine" media player app. Youtube and Mplayer get a lot of use as well. The audio is just using the stock optical out on the Intel motherboard. This PC is about 4 years old but works just fine, and runs extremely quiet despite it's two fans. TV - Sony Bravia KDL40 EX500 40" LCD TV. This mostly gets used as a monitor for the PC, but the optical out is hooked up for the rare TV session. DVD/CD player. An old DSE "Digitor" DVD player. Definitely not a high grade unit, not often used but it does appear to handle a lot of formats so kept around. Other bits. Interconnects are mostly DIY from Altronics and Jaycar parts. Wireless keyboard and mouse. Speaker cables and optical cables from Selby Acoustic. ALDI master/slave powerboard - this is very handy, it uses the TV as a master device and turns off the amps & miniDSP when the TV goes into full standby mode, about 15 minutes after the TV is turned off with the remote. Not such a big deal with the miniDSP and Class T amp, but great once Class A amplification was added to the mix. So the whole system (except the PC) can be powered on/off from the TV remote. I've intentionally assembled all gear with no panel lights to cause distractions, the lights on lots of gear were annoying my wife. Things still to do: I still have a lot of work to do refining the crossover, I've done some initial work with The Active Crossover Designer with good results, but I really need to dig much deeper here. I've had a lot of help and advice from the guys in the SNA DIY section, thanks! I'm not completely happy with the finish on the speaker enclosures. The third coat of stain/varnish was applied at night and I didn't see the drips and patchy bits. One day I'll haul them out for another sand and coat. But its OK. The digital source is pretty much "out of the box" Linux with Pulseaudio. Apart from verifying I'm getting unmodified 16bit/44100 for CD quality flac files, I haven't explored too far here. The miniDIGI does on the fly samplerate conversion and reclocking to 48khz so maybe it doesn't matter.