QUATTRO mkII, built by Phil, Germany
Copyright 2019 © Troels Gravesen

 Hello Troels,
After looking into my project folder, I realised my Quattro build turns 4 (quattro) and I haven’t send you any feedback to the builders response page. So here it comes finally.
I started making the Quattro loudspeakers when I was a student. The conditions were anything but good. My room in the dorm had 14 square meters. Kindly I could do the grinding work on the terrace of the student bar. The gluing of the boards and the final painting was done in my room. As you can see on the photos I made a few simplifications in the wood construction method. Maybe I will paint them, but at the moment I still like the multiplex look very much. I was able to solder the internal crossover in my university.
Occasionally I used a horn subwoofer as an extension into the deep areas (still in the 14 square meter room). After 4 years of use I could hear the loudspeakers in different rooms and currently operate them single with a DSP (miniDSP).
But now to the sound: I am happy with the sound. The loudspeakers have become my reference loudspeakers. Acoustic music generally sounds very good. Actually, any music sounds great on them, even very loud.
Among other things, I listen to electronic genres and they do not have enough depth for that.  That's why I also use the DSP to rise the gain until 30Hz.
I measured them in the student room for fun, but you can't use the measurement. I use a 100W amplifier to fire them. The final pricetag were 560€ per speaker.
I’m in love with the OBL-15 since a long time, because I expect a lot from the open baffle design. Unfortunately I don't have room for the construction at the moment. Will you introduce more speakers in this direction? Judging by your review you liked them very much.
Many greetings from Munich