OBL-15, built by Nash, US
Copyright 2018 © Troels Gravesen

I finished building these OBL15’s around two months ago and have experimented with placing them in different positions. They sound best so far, placed 96 inches apart tweeter to tweeter, 57 inches from the front wall and 31 inches to the side wall in reference to the tweeter. I followed Troels  build instructions to the millimeter using two 18mm Baltic birch panels for the face and an additional 21mm Baltic birch for the mid and woofer. Finish is a violin red water based dye followed with General Finishes ArmRSeal poly varnish clear. To make it more aesthetically pleasing the side edges have been chamfered and the crossover parts have been placed in a box under the bottom panel. This is an Audax  Level 1 build.
 
My previous speakers were Bowers & Wilkins DM6 which sounded very detailed and presented a big realistic soundstage. I listen to mostly classical. I am using a Salas DCG3 preamp and Pass design F5TV3 monoblocks of around 100W each. My first impression upon listening was on how smooth the OBL15’s sounded but felt that the bass was excessive and a bit light in the mids. I discovered thru experimentation that the front edge of the speaker where most of the weight is, was digging into my plush pile carpet reducing the designed in 5 degree tilt. Upon adding a thin shim underneath I increased the tilt and now the sound is far more balanced.
 
The detail is more than with my DM6’s and more naturally so. The overall presentation is full and rich. All instruments are correctly positioned and defined and the sound stage gives the impression of instruments all projecting sound together like in a real concert hall as opposed to pinpoints of sound. Violins sound exceptionally refined and smooth, perhaps because of the Jantzen Alumen supercap used. Lower register clarity especially of pianos is superb. What I was not prepared for is how clear soft passages in the music sound and the loud passages get very loud in a hurry. I am now experiencing what dynamics really is! Troels says “I dare guarantee the OBL-15 will deliver a live feeling”. Guarantee delivered! I have read that the difference between good speakers and great ones is really in three areas- detail, dimensionality and dynamics. OBL15 excels in all three.
 
Thank you Troels for this great design and for the help you extended to me throughout the build process. Thanks also to Michael Dahl Jantzen of Jantzen Audio for your help and encouragement.
 
Nash in New Jersey, USA