Looks like they decided to wave the 10+% additional cost that they were going to charge after I informed them I was going to cancel the order. The original purchase price was then offered so I went through with the order.
Trying hard to chalk it up to extenuating circumstances in my mind. Hopefully the next order will go a smoother or I will be done using them.
Trying hard to chalk it up to extenuating circumstances in my mind. Hopefully the next order will go a smoother or I will be done using them.
Bass array drivers arrived! Mounted, 3 in parallel and then in series. Measured RE is 4 Ohms.
Must work on the xovers measurements ect. Just finished the mechanical so was eager to get in a test session. Everything is sub par right now but........ so far sounds really clean. More to come later.
Must work on the xovers measurements ect. Just finished the mechanical so was eager to get in a test session. Everything is sub par right now but........ so far sounds really clean. More to come later.
Attachments
OK now I can see how it goes together. My first thought was some kind of coaxial arrangement. I like that clear baffle, shades of Soulsonic. Nice thing about OB is you don't have to build boxes...
Eager to hear a more detailed review
)) and see measurements.
I'm interested in the PTmini. If anything, you will have too much treble dispersion but dipole arrangement will narrow it nicely.
How close together are you able to stack the PTminis, given the terminals coming off the ends?
Eager to hear a more detailed review
)) and see measurements.I'm interested in the PTmini. If anything, you will have too much treble dispersion but dipole arrangement will narrow it nicely.
How close together are you able to stack the PTminis, given the terminals coming off the ends?
Thanks! Decided to bite the bullet and get those made clear, didn't want them to look too imposing but they are still quite big to look at.
Eager to hear a more detailed review
Going to try and get some good measurements. Since the baffles are fixed not sure how good they will be but they will contain all warts of in room response! Will be taking a number of strange nearfield measurements between the baffle but it probably won't tell much. These will come at a later date, after the initial wow wears off hehe.
The PT minis are not running dipole right now. Going to see how they perform subjectively before doing the back to back PT minis in dipole config. In the past I've had trouble with treble dispersion in my room so I wanted to try something ultra-wide this time. The PT mini fit that bill perfectly and has great form factor.
The drill holes for the terminals are spaced at roughly 83.5mm. Of course my hand drilling is not that precise so manual tolerances observed but everything fit nicely with PT mini frames touching each other. I drilled all the terminal holes at one time before mounting any drivers so it should be doable. It was relatively painless to do. Sticky tape worked out great for mounting, gave a bit of wiggle room. Also didn't have to drill holes or screw in a large # of screws! Much easier. The home depot red double sided sticky tape holds them pretty strongly. I have to work at it to get them off the frame but they also provide some damping between the hard BB surface and the pack metal plate.
I bent the terminals back 90 degrees from their original position using needle nose pliers. It is totally doable without wrecking the part. Seems they use that liquid black tape or sticky black glue to put the back metal panel together. If one pulls too hard you might rip it off, just be careful. Also I used pliers to hold the terminals when I put on the quick connects. It wasn't too difficult........but be careful. Soldering the SB drivers was an order of magnitude harder.
Mike, this is reminding me of a minimalist, modern version of the Infinity Reference Standard IRS / V from the late 80s!
Mike, this is reminding me of a minimalist, modern version of the Infinity Reference Standard IRS / V from the late 80s!
Those look fantastic! Would be neat to hear them in a good room setup correctly.
Subjective impressions
Time for a few comments on subjective performance. I should be careful here but almost across the board improvement over the SB 36 driver array.
Bass is impressive. Not overblown but effortless and clean. Has depth and extension in all the right places. Feels like a race car with the volume control. Had them very loud and the cones were hardly moving. Put my finger on them to make sure everything was connected correctly. SPL seems to scale without compression. When asked to play something, they just play, no question asked. Something the 36 array struggled with. The 36 array cannot go loud playing fullrange. While this is not unexpected the difference in these 2 builds is vast. No room pressurization like sealed sources. Midbass is fuller and low volume cruzes along, something the 36 array struggled with. The 36 array being sealed felt closed in, like all sealed builds in my room.
Midrange is more open. Lacking that last bit in imaging as compared with the horns. Presentation is more diffused. Obviously being OB soundstage is moved back further than the 36 array. Midrange on the 36 was very good but lacking the OB build detail. OB Seems to pull more background sounds out of recordings than the 36 array. Pulling out background sounds seemed to be something the LA are very good at. Makes movie watching a mixed blessing depending on the mix. Initially with the XOVER at 7khz presentation was too bright. Seemed hard, probably too much high frequency sprayed around the room. Moved the XOVER to 10khz and presentation is much better. Everything seems to gel. At this point will probably not spend the extra $$$ to make the tweeters fully "dipole" operation since they are only working at +10khz. Without them the NEO8-PDR sounds dark and recessed.
Treble is better than the 36 array. Everything the 36 array was missing is now being played in spades with the OB 3-Way. In almost all respects this is not a fair comparison but presentation wise the OB 3-way is a lot more to my liking, seems to do everything well with very little shortcomings. Of course everything is a compromise so.......
What they don't do well is image like the horns. Everything is more diffused. Lacking that nth degree depth. But the bass presentation is really something, best I've had in this room, even compared with 4 distributed sealed subs configuration. Also seat variations seems less across the couch than other builds. Overall exceeded expectations as a whole. Was worried it they wouldn't perform much better than the 36 array overall but the OB 3-Way plays in a different league, really glad they sound great.
Still have to do a large number of measurements but the quick and dirty sounded so good I've just been listening to everything non-stop. Something I never did with the 36 array. If one were to build a LA you should think hard and long as to what kind of presentation you like. The fullrange driver LA doesn't make any magic that was not there before. If you like OB, then stick with an OB LA build, if you prefer single driver fullrange sealed or vented presentation then that is the array you should build.
I would err on the side of doing complete LA build, meaning make sure to have a LA of low frequency drivers that will NOT require additional bass support. Overbuild the low frequency portion of the LA, the presentation gained from doing this is really something else. I've run point source dual OB 15s, this is different animal. Not sure if its the LA config or the shear headroom available but..........wow! These are my new reference speakers, XOVER 330hz BW3ish and 10khz BW3ish, measurements to come at a later date, too busy listening right now. They probably measure like rubbish as compared to a number of builds on here but beauty is in the eye of the beholder.
Time for a few comments on subjective performance. I should be careful here but almost across the board improvement over the SB 36 driver array.
Bass is impressive. Not overblown but effortless and clean. Has depth and extension in all the right places. Feels like a race car with the volume control. Had them very loud and the cones were hardly moving. Put my finger on them to make sure everything was connected correctly. SPL seems to scale without compression. When asked to play something, they just play, no question asked. Something the 36 array struggled with. The 36 array cannot go loud playing fullrange. While this is not unexpected the difference in these 2 builds is vast. No room pressurization like sealed sources. Midbass is fuller and low volume cruzes along, something the 36 array struggled with. The 36 array being sealed felt closed in, like all sealed builds in my room.
Midrange is more open. Lacking that last bit in imaging as compared with the horns. Presentation is more diffused. Obviously being OB soundstage is moved back further than the 36 array. Midrange on the 36 was very good but lacking the OB build detail. OB Seems to pull more background sounds out of recordings than the 36 array. Pulling out background sounds seemed to be something the LA are very good at. Makes movie watching a mixed blessing depending on the mix. Initially with the XOVER at 7khz presentation was too bright. Seemed hard, probably too much high frequency sprayed around the room. Moved the XOVER to 10khz and presentation is much better. Everything seems to gel. At this point will probably not spend the extra $$$ to make the tweeters fully "dipole" operation since they are only working at +10khz. Without them the NEO8-PDR sounds dark and recessed.
Treble is better than the 36 array. Everything the 36 array was missing is now being played in spades with the OB 3-Way. In almost all respects this is not a fair comparison but presentation wise the OB 3-way is a lot more to my liking, seems to do everything well with very little shortcomings. Of course everything is a compromise so.......
What they don't do well is image like the horns. Everything is more diffused. Lacking that nth degree depth. But the bass presentation is really something, best I've had in this room, even compared with 4 distributed sealed subs configuration. Also seat variations seems less across the couch than other builds. Overall exceeded expectations as a whole. Was worried it they wouldn't perform much better than the 36 array overall but the OB 3-Way plays in a different league, really glad they sound great.
Still have to do a large number of measurements but the quick and dirty sounded so good I've just been listening to everything non-stop. Something I never did with the 36 array. If one were to build a LA you should think hard and long as to what kind of presentation you like. The fullrange driver LA doesn't make any magic that was not there before. If you like OB, then stick with an OB LA build, if you prefer single driver fullrange sealed or vented presentation then that is the array you should build.
I would err on the side of doing complete LA build, meaning make sure to have a LA of low frequency drivers that will NOT require additional bass support. Overbuild the low frequency portion of the LA, the presentation gained from doing this is really something else. I've run point source dual OB 15s, this is different animal. Not sure if its the LA config or the shear headroom available but..........wow! These are my new reference speakers, XOVER 330hz BW3ish and 10khz BW3ish, measurements to come at a later date, too busy listening right now. They probably measure like rubbish as compared to a number of builds on here but beauty is in the eye of the beholder.
Thanks! Pics and measurements will be coming when I get the space cleaned a bit also they are a bit too close to the side wall but this is the only place they can go.
Yes, big difference between the 36 SB driver, 2x15" OB, single 18" OB, 4x12" sealed ect. and 6x15" OB per side. The 6x15" OB per side simply sound different. Either room loading or surface area or both but they sound like unlimited OB subs+bass. It really is something. Clean is the word that keeps coming to mind, although since its OB I'm sure they are distorting, but it must be the good distortion!
also they are a bit too close to the side wall but this is the only place they can go.Yes, big difference between the 36 SB driver, 2x15" OB, single 18" OB, 4x12" sealed ect. and 6x15" OB per side. The 6x15" OB per side simply sound different. Either room loading or surface area or both but they sound like unlimited OB subs+bass. It really is something. Clean is the word that keeps coming to mind, although since its OB I'm sure they are distorting, but it must be the good distortion!
Awesome build! Looking forward to further developments. Has a lot of potential to be a very high resolution system. Great choice on components.
How far off the back wall are these going to be? Some damping or diffusion behind the mids might get your imaging cleaner without detracting from the "boxless" sound. At least that's what I noticed when playing with open baffle.
How far off the back wall are these going to be? Some damping or diffusion behind the mids might get your imaging cleaner without detracting from the "boxless" sound. At least that's what I noticed when playing with open baffle.
Thanks for the tip! Currently they are 3 feet from the front wall but only 15" off the side wall (LA OB woofers closest to the wall, mids and tweeter on the inside). There is some bad stuff (TV and screen) between the speakers. It is a multifunction room so no choice here.
Had some dampling panels on the front wall behind the speakers but had to move them out as they were better suited in another location. I should order a few more or temporarily move them back for some testing. I do have damping on the side walls though.
Thanks! I don't listen to music as loud as the next guy but when cranked there is no motor noise as far as I can tell. Cone movement is minimal when loud even with no High Pass filter installed on woofer section. My mic is not calibrated to absolute level but will get some distortion sweeps done at high SPL someday.
Thanks! Pics and measurements will be coming when I get the space cleaned a bit
Yes, big difference between the 36 SB driver, 2x15" OB, single 18" OB, 4x12" sealed ect. and 6x15" OB per side. The 6x15" OB per side simply sound different. Either room loading or surface area or both but they sound like unlimited OB subs+bass. It really is something. Clean is the word that keeps coming to mind, although since its OB I'm sure they are distorting, but it must be the good distortion!
Awesome OB LA build!
- I'm wondering what the differences in sound between the Deltalites compared to higher qts drivers (Alpha 15A's, GRS, etc)? I assume with the Deltalites it might be cleaner and a tad leaner than higher qts drivers?
- How would a coaxial type setup with 5.25 to 8" drivers flanking the tweeter line be different in sound?
- What effects does a coaxial OB LA type setup have on lobing and comb filtering?
- Why the GRS Slims vs the regular 8s? The distortion plots looked better on the reg 8's.
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all 4 questions are very interesting, and probably no way of finding out without actual testing. I have a 2,5m long mono OB line array with 3" fullrange drivers. They sound bad standing 1m away, but very nice when about 3 to 4m away.
Mlee did use original B&G drivers, not the Slims. I used the slims vs the regular NEO 8 clones because the slims do highs better.
Mlee did use original B&G drivers, not the Slims. I used the slims vs the regular NEO 8 clones because the slims do highs better.