I recently upgraded from N3 towers (N3TL) to the OB-5 towers so I thought I would share my impressions with other AC members. My experience with GR Research started with a pair of demo N1X speakers that Danny was circulating around the country. After liking what I heard, I built a pair of N3S speakers using PE enclosures. The next upgrade was to N3TL but this time I had Ruben (aka: Outofthewoods) build me a beautiful pair of enclosures. My latest upgrade was to the subject of this post, the OB-5s. Again, I had Ruben build the enclosures and again, he did an outstanding job. He is a true craftsman.
A little background about my preferences will help explain why I felt a need to change from N3TL to OB-5. Over the years I have owned several speakers of the monopole, bi-pole, and di-pole variety. Speakers I’ve owned include the following (In no particular order):
Monopole: OHM, ADS, Klipsch, B&W, JBL, GR Research N3S and N3TL.
Bi-pole & Di-pole: Infinity RS2.5, Mirage M7-Si, Apogee Caliper Signature, Magnepan MMG (still own the Maggies) and now the GR Research OB-5.
If I were to list the above speakers in chronological order of ownership, it would show that I more or less alternated between monopole and bi-pole/di-pole types. What I figured out is that the two sound characteristics that prompted me to “change” were the focus and detail associated with monopoles and the openness and super wide soundstage associated with bi-poles & di-poles. In hindsight, I was looking for a speaker that could give me both focus AND super wide soundstage. I am happy to report that the OB-5 gets me closer than ever to my goal.
Because I sold my N3TLs a few weeks prior to completing the OB-5 build, the following comments are based on my memory of the N3TL sound. The first thing I noticed was that these speakers are slightly more forward than the N3TL. In my room, that’s a good thing because I felt that the N3TL were just a touch recessed in the mids. High frequencies are smooth, refined, accurate, natural and absolutely musical. Just like the N3TL. Love that planer magnetic tweeter! The next thing I noticed was that the bass is very well defined and goes down quite deep. I listened to some music with low end punch like The Kinks Low Budget, Heart Dreamboat Anne, Donald Fagen The Nightfly, Jennifer Warnes Famous Blue Raincoat and Jackson Browne Hold Out. As far as I can remember, the bass is at least as deep as the N3TLs. Maybe even deeper. This surprised me because Danny’s specifications show that the N3TL measures slightly better in the bass output. In both cases, the two identical subwoofers I use were positioned left and right of each speaker (N3TL / OB-5), wired in stereo and crossed over at 50Hz while the main speakers ran full range. With the OB-5s I can live without the subs on some music but usually leave them on to fill in the very bottom end. With a little help from a pair of subwoofers, the OB-5 is a totally satisfying speaker. In short I am very happy I upgraded to the OB-5s and don’t see myself replacing them any time soon.
NOTE: The enclosures include NoRez and the crossovers include Platinum bypass caps. The finish is satin black on the base and baffle with black leatherette on the woofer enclosure.
Room and speaker position: The room is 13ft X 21ft with no wall behind the listening position which means it’s really 13ft x 40ft. (My family room is open to the dinette and kitchen areas). The 13ft x 21ft family room area is carpeted and includes typical curtains, sofa, chairs, etc. I positioned the OB-5s in the same spot as the N3TLs were located which resulted in a distance of 50 inches from front wall to the back side of the open baffle and 32 inches from the side wall to speaker centerline. Speakers are parallel to the front wall (no toe in). Listening position is 12 ft from the plane of the speaker baffles.
Sources: Thorens TD126 Mk 2 / SME 309 / Ortofon MC Rondo Blue and OPPO BDP95
Preamp/Amp: Threshold SL10 / McCormack DNA 0.5 Deluxe
Subwoofers: (2) Mirage BPS150i (Bi-Polar design with a pair of 8" drivers in each enclosure)
