The migration from the LXmini-inspired pentagon tower to omni is nearly complete. I went through several iterations of 3D-printed reflectors and settled on a version that has a profile quite close to the cone of the 6.5" Seas driver. The ball reflector for the SB TW29RN tweeter developed a... nipple, for want of a better word.
Both bass & tweeter reflectors ended up much closer to the drivers, the former with unintended results: They ended up a bit too close so that somewhere along the way, with high excursions, the center piece of the aluminum cones bumped into the tip of the deflector and got crushed in a bit. A pain to pull the crushed part out and there's evidence of the damage, but I can't hear or measure any ill effects. I had to use some screws on the legs to raise the reflector (and tweeter housing) so this would not recur.
The drivers are actively driven with two 2x150W amp modules from @Erica.C and a miniDSP 2x4HD splits the band at 2kHz LR2. Tried lots of different configs; I kept coming back to this one. A +4dB low shelf at 70Hz & sharp notch cut at 6.5 kHz (to quell the metal cone breakup) are the main PEQ for the woofer. Tweeter gets a -3dB gentle cut at 3.5 kHz. That's about it.
The sources are JRiver on my PC, Qobuz through it to USB, and also Qobuz via the cheap Wiim streamer puck feeding the optical input of the minidsp.
From any of the above sources, the sound is generally rich, full, detailed, the spatial presentation expansive & pleasant. Bass is shockingly believable. The disconnect between the visual of the wee 6.5" driver & 1.1" tweeter vs the sonic presentation makes one double take. The best thing is almost complete freedom from "one best seat" syndrome. It sounds great standing, sitting, almost anywhere in the room. The character of the sound hardly changes at all as you walk around. And it does this even 2' from the wall behind it.
I don't have final measurements to show, as the last set done via REW a week ago got accidentally wiped. At 90 dB/1m bass is flat to ~40Hz, and overall FR curve is flattish. Nothing like the +,- 2dB smoothness some members post, but decently smooth. It sounds unstrained to ~100 dB@1m -- not quite as loud I sometimes like to play, but generally plenty loud enough.
A significant test will come this afternoon, as my neighbor/friends have asked to audition these temporarily with the Wiim puck. They have heard the system here & love it but want to know what can sound like in their much bigger vaulted ceiling space. I'll be taking the measurement system over to double check & fine-tune as necessary. It'll be great fun! 👍😊
Both bass & tweeter reflectors ended up much closer to the drivers, the former with unintended results: They ended up a bit too close so that somewhere along the way, with high excursions, the center piece of the aluminum cones bumped into the tip of the deflector and got crushed in a bit. A pain to pull the crushed part out and there's evidence of the damage, but I can't hear or measure any ill effects. I had to use some screws on the legs to raise the reflector (and tweeter housing) so this would not recur.
The drivers are actively driven with two 2x150W amp modules from @Erica.C and a miniDSP 2x4HD splits the band at 2kHz LR2. Tried lots of different configs; I kept coming back to this one. A +4dB low shelf at 70Hz & sharp notch cut at 6.5 kHz (to quell the metal cone breakup) are the main PEQ for the woofer. Tweeter gets a -3dB gentle cut at 3.5 kHz. That's about it.
The sources are JRiver on my PC, Qobuz through it to USB, and also Qobuz via the cheap Wiim streamer puck feeding the optical input of the minidsp.
From any of the above sources, the sound is generally rich, full, detailed, the spatial presentation expansive & pleasant. Bass is shockingly believable. The disconnect between the visual of the wee 6.5" driver & 1.1" tweeter vs the sonic presentation makes one double take. The best thing is almost complete freedom from "one best seat" syndrome. It sounds great standing, sitting, almost anywhere in the room. The character of the sound hardly changes at all as you walk around. And it does this even 2' from the wall behind it.
I don't have final measurements to show, as the last set done via REW a week ago got accidentally wiped. At 90 dB/1m bass is flat to ~40Hz, and overall FR curve is flattish. Nothing like the +,- 2dB smoothness some members post, but decently smooth. It sounds unstrained to ~100 dB@1m -- not quite as loud I sometimes like to play, but generally plenty loud enough.
A significant test will come this afternoon, as my neighbor/friends have asked to audition these temporarily with the Wiim puck. They have heard the system here & love it but want to know what can sound like in their much bigger vaulted ceiling space. I'll be taking the measurement system over to double check & fine-tune as necessary. It'll be great fun! 👍😊
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Actually when the reflections are very uniform you sort of disregard them (assuming your hearing isn’t messed-up), provided you have a direct gradient from ears to the source/driver(s). One thing that can be problematic is freq. balance where the reflections can increase the perceived higher freq.s of the loudspeaker.. you can also adapt to that, but it’s not as easy to correct for and it’s nearly impossible to account for if there is a resulting inter-channel imbalance where those reflections make one speaker sound louder than another.
1.5-7.5kHz is critical for the gradient (basically you should be able to see the tweeter for both loudspeakers at all times even if it’s just the very tip of it).
1.5-7.5kHz is critical for the gradient (basically you should be able to see the tweeter for both loudspeakers at all times even if it’s just the very tip of it).
Wednesday's trial at my friends' place began disastrously. Simple transfer of gear to a house less than half a km away should be easy, right? Not so much.
1. The USB power supply I'd been using for the Wiim Mini was left behind, so a spare in the neighbors' house was used. Not good. The phone could not find the Wiim via Bluetooth. Took a while to discover the power supply didn't have enough juice. Replacing it finally got us going.
2. The MiniDSP 2x4HD somehow lost all its settings. This seems odd; I don't recall experiencing this before! I had to go back and retrieve the config files from my studio computer, then confirm everything was back to the way it had been before the move. Aside: Has anyone experienced this loss of configs in the minidsp firmware before?
Finally the amp, minidsp, Wiim & speakers were set up in the desired spot (~70cm from back wall, perhaps 40cm distance to side walls) in the slight alcove where their 60" LG TV is wall mounted, and some sound was coming from the speakers. By then other friends had arrived for dinner, so any measurements or experiments had to be postponed. Qobuz was left running to stream an eclectic mix of music at modest volume throughout the evening.
My subjective assessment: The sound was far too diffuse, the bass disappeared, and all the magic of the system in my studio was gone. Adding some 6-8 dB boost of bass with the Wiim EQ helped but it was still too wispy & ethereal sounding to me. The others present thought it sounded great -- but their reference is a Google or Amazon "smart" speaker.
The room is voluminous. The peak of the vaulted ceiling is around 14'. The LR extends about 40' from the wall behind the speakers, broken up by the primary seating area, a grand piano beyond that, and a secondary seating area. It's open to the kitchen and DR as well, so the entire roughly 40' by 30+' space is open. A lot of space for a pair of 6.5" drivers. I planned to return the next day and investigate further.
1. The USB power supply I'd been using for the Wiim Mini was left behind, so a spare in the neighbors' house was used. Not good. The phone could not find the Wiim via Bluetooth. Took a while to discover the power supply didn't have enough juice. Replacing it finally got us going.
2. The MiniDSP 2x4HD somehow lost all its settings. This seems odd; I don't recall experiencing this before! I had to go back and retrieve the config files from my studio computer, then confirm everything was back to the way it had been before the move. Aside: Has anyone experienced this loss of configs in the minidsp firmware before?
Finally the amp, minidsp, Wiim & speakers were set up in the desired spot (~70cm from back wall, perhaps 40cm distance to side walls) in the slight alcove where their 60" LG TV is wall mounted, and some sound was coming from the speakers. By then other friends had arrived for dinner, so any measurements or experiments had to be postponed. Qobuz was left running to stream an eclectic mix of music at modest volume throughout the evening.
My subjective assessment: The sound was far too diffuse, the bass disappeared, and all the magic of the system in my studio was gone. Adding some 6-8 dB boost of bass with the Wiim EQ helped but it was still too wispy & ethereal sounding to me. The others present thought it sounded great -- but their reference is a Google or Amazon "smart" speaker.
The room is voluminous. The peak of the vaulted ceiling is around 14'. The LR extends about 40' from the wall behind the speakers, broken up by the primary seating area, a grand piano beyond that, and a secondary seating area. It's open to the kitchen and DR as well, so the entire roughly 40' by 30+' space is open. A lot of space for a pair of 6.5" drivers. I planned to return the next day and investigate further.
On-site setup & adjustments, Day 2:
Some days later, I returned with a Dayton EMM-6 mic, TASCAM UD7000 digital mic preamp & laptop and all the necessary cables to run sweeps with REW & adjust the minidsp as necessary. I had a couple of hours on my own to try things, but with Jan on a conference biz call somewhere in the house, I kept the sweeps at a very low level -- too low, REW complained, but I already know the distortion characteristics, so...
I began by simply listening to music through the system as set up the previous day (Qobuz>Wiim>minidsp>amps) and walking around the entire open space. The diffuse, wispy character I noted was worse farther from the speakers and not bad from the primary seating area in front of the TV & speakers. But it was still too bright and thin. (In case I didn't mention this before, the speakers are likely to be used half the time for TV sound.)
The first FR sweep of the left speaker through the USB input of the minidsp 2x4HD showed the tweeter output to be significantly higher than the woofer output. Reducing the tweeter level by 3dB helped. This is a direct effect, I believe, of the much higher undamped reflectivity of the walls in this space, compared to my well-damped studio.
Sweeps of the right speaker revealed differences in the bass between the two speakers. The left is a more complete corner, the recess into the alcove being >5', while the right corner is impinged by the fireplace at around 2.5'. The fireplace faces the room at a 45 degree angle, making the far side of the right speaker more open, hence reflecting/loading the bass differently. I decided it was not worth trying to correct the L-R bass imbalance as it wasn't very audible anyway.
Loudspeakers designed specifically for forward radiation in the corners might be a better solution than these omnis -- something along the lines of the old Allison Three, but with a waveguide for the tweeter to reduce reflection off the walls. They'd end up about 10' apart, which wouldn't be too bad considering that the nearest seat is at least that distance from the center point between the speakers.
I decided to give corner positions a try, using a cushion behind the top of each speaker to absorb the rear radiation. This corner setup eliminated the overly reverberant, "wispy" aspect of the sound and significantly increased the general amplitude of the bass. But it also created a hole in the middle effect. This could not be corrected with any miniDSP PEQ manipulations.
Several other positions were tried in incremental 6" steps from the corners, with quick sweeps through both speakers done at 1.5m from the centerpoint between the speakers. At roughly 14" from the wall behind the speakers and 18" from the sides, the FR flattened out considerably. I paused here to make more sweeps from different positions, particularly going backwards towards the main listening area. At the ~10' distance, where the main seating is located, a relatively flat FR was measured.
Because the measuring distance was so far, it's hard to correlate the THD below to a standard one meter measurement, but I share it anyway. At this level, it is below 1% till below 100Hz & doesn't reach 2% till below 50Hz. (And yeah, there are two speakers being run.)
Aside from level matching between the drivers, the +4dB low shelf was lowered from 70Hz to 55Hz, & the woofer cone breakup notch cut was set to 6kHz. The tweeter got a -2dB gentle cut at 3.5 kHz, -2dB Q=2.5 cut at ~10kHz, and a +5dB Q=1.0 peak boost at 20 kHz.
A variety of sound sources were tried, from my Qobuz favorites (via wifi & optical between Wiim Mini & miniDSP) as well as TV sound (via analog from TV into Wiim Mini), the latter mostly comprising soundtrack for Netflix & YouTube videos.
Subjectively, this was the best sound achieved in the primary listening area thus far: Open, smooth, broadband, fairly dynamic, with a somewhat diffuse but appealingly large sound stage. Poor quality tracks sounded poorly; no surprise. The best tracks were delivered with enough authority (bass and mid-range punch) and no obvious distortion even in the bass up to maybe 95 dB at the listening position. (Note that the distance to the speakers is >10'.) Overall, the performance isn't what I heard in my studio, and I believe well-designed forward-firing, higher directivity speakers would probably satisfy me better, but it's better than mid-fi.
Lisa & Jan, my "clients" for this project, felt the sound was improved, but was hard pressed to describe exactly how. They are of the opin that this is plenty good enough for them and want me to move on with finalizing and finishing the system. I probably shouldn't argue with happy clients.
The next step is a Wiim Pro or Pro+ to replace the Wiim mini, 3D print a better fitting reflector for the woofer, and either finish the existing pentagon towers with a cloth wrap & hardwood top baffle -- or build them a fresh new pair of enclosures from a sturdier material, perhaps 15mm BB plywood instead of the 1/2" MDF. I could also pretty up the amp casing a bit.
Some days later, I returned with a Dayton EMM-6 mic, TASCAM UD7000 digital mic preamp & laptop and all the necessary cables to run sweeps with REW & adjust the minidsp as necessary. I had a couple of hours on my own to try things, but with Jan on a conference biz call somewhere in the house, I kept the sweeps at a very low level -- too low, REW complained, but I already know the distortion characteristics, so...
I began by simply listening to music through the system as set up the previous day (Qobuz>Wiim>minidsp>amps) and walking around the entire open space. The diffuse, wispy character I noted was worse farther from the speakers and not bad from the primary seating area in front of the TV & speakers. But it was still too bright and thin. (In case I didn't mention this before, the speakers are likely to be used half the time for TV sound.)
The first FR sweep of the left speaker through the USB input of the minidsp 2x4HD showed the tweeter output to be significantly higher than the woofer output. Reducing the tweeter level by 3dB helped. This is a direct effect, I believe, of the much higher undamped reflectivity of the walls in this space, compared to my well-damped studio.
Sweeps of the right speaker revealed differences in the bass between the two speakers. The left is a more complete corner, the recess into the alcove being >5', while the right corner is impinged by the fireplace at around 2.5'. The fireplace faces the room at a 45 degree angle, making the far side of the right speaker more open, hence reflecting/loading the bass differently. I decided it was not worth trying to correct the L-R bass imbalance as it wasn't very audible anyway.
Loudspeakers designed specifically for forward radiation in the corners might be a better solution than these omnis -- something along the lines of the old Allison Three, but with a waveguide for the tweeter to reduce reflection off the walls. They'd end up about 10' apart, which wouldn't be too bad considering that the nearest seat is at least that distance from the center point between the speakers.
I decided to give corner positions a try, using a cushion behind the top of each speaker to absorb the rear radiation. This corner setup eliminated the overly reverberant, "wispy" aspect of the sound and significantly increased the general amplitude of the bass. But it also created a hole in the middle effect. This could not be corrected with any miniDSP PEQ manipulations.
Several other positions were tried in incremental 6" steps from the corners, with quick sweeps through both speakers done at 1.5m from the centerpoint between the speakers. At roughly 14" from the wall behind the speakers and 18" from the sides, the FR flattened out considerably. I paused here to make more sweeps from different positions, particularly going backwards towards the main listening area. At the ~10' distance, where the main seating is located, a relatively flat FR was measured.
Because the measuring distance was so far, it's hard to correlate the THD below to a standard one meter measurement, but I share it anyway. At this level, it is below 1% till below 100Hz & doesn't reach 2% till below 50Hz. (And yeah, there are two speakers being run.)
Aside from level matching between the drivers, the +4dB low shelf was lowered from 70Hz to 55Hz, & the woofer cone breakup notch cut was set to 6kHz. The tweeter got a -2dB gentle cut at 3.5 kHz, -2dB Q=2.5 cut at ~10kHz, and a +5dB Q=1.0 peak boost at 20 kHz.
A variety of sound sources were tried, from my Qobuz favorites (via wifi & optical between Wiim Mini & miniDSP) as well as TV sound (via analog from TV into Wiim Mini), the latter mostly comprising soundtrack for Netflix & YouTube videos.
Subjectively, this was the best sound achieved in the primary listening area thus far: Open, smooth, broadband, fairly dynamic, with a somewhat diffuse but appealingly large sound stage. Poor quality tracks sounded poorly; no surprise. The best tracks were delivered with enough authority (bass and mid-range punch) and no obvious distortion even in the bass up to maybe 95 dB at the listening position. (Note that the distance to the speakers is >10'.) Overall, the performance isn't what I heard in my studio, and I believe well-designed forward-firing, higher directivity speakers would probably satisfy me better, but it's better than mid-fi.
Lisa & Jan, my "clients" for this project, felt the sound was improved, but was hard pressed to describe exactly how. They are of the opin that this is plenty good enough for them and want me to move on with finalizing and finishing the system. I probably shouldn't argue with happy clients.
The next step is a Wiim Pro or Pro+ to replace the Wiim mini, 3D print a better fitting reflector for the woofer, and either finish the existing pentagon towers with a cloth wrap & hardwood top baffle -- or build them a fresh new pair of enclosures from a sturdier material, perhaps 15mm BB plywood instead of the 1/2" MDF. I could also pretty up the amp casing a bit.
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Room sound looks thin in bass... and some extra in 1-3kHz range. I would lift bass 4-6dB below 300Hz!
See Harman curve by listening tests https://www.diyaudio.com/community/threads/current-harman-room-curve.363497/
See Harman curve by listening tests https://www.diyaudio.com/community/threads/current-harman-room-curve.363497/
@mikessi
These log cabins in the middle of a forest of tall trees, surrounded by oceans reminds me of good times in BC. Stunning.
I haven't followed your thread too closely so please excuse my ignorance if there’s something I’m missing about your speaker design. It may be the Omnipolar nature of the speakers in a large room with all the hard reflective surfaces, giving a wispy airy and slightly thin sound. But it might be due to just having a single 6.5” per side.
Big rooms benefit from big woofers, IME.
I once had a room with 20’ W x 30’ D with 12’ ceiling, that opened into another room:
Hard reflective surfaces everywhere. The speakers were monopole, and each had twin ported 8” RS225 woofers (Statement II, courtesy @jholtz and Curt Campbell):
And although they sounded JUST right to me, here was the in-room response, as measured by Dirac’s average of 9 point response about the listening position:
(1 speaker)
Both speakers:
Did it sound like too much bass with all that lift below 80Hz? Not at all!
I’m with Juha. It might benefit from a bit of bass lift. A monopole subwoofers behind each speaker would probably be a the quickest way to add that. (If the clients care)
PS.
My old miniDSP nanoDigi device gives up every so often. Once I thought it died. Turns out it was a DAC incompatibility (who’s heard of such a thing?! Not me!).
Plugging back the old DACs solved the issue (hint: if it ain’t broke, don’t fix it)
Other times Power cycling helps. (Hint: when it doesn’t connect to the PC)
Once I had to reflash the firmware and reload the configuration files (hint: Input meter jumps around, even without any input)
Crazy.🤪
These log cabins in the middle of a forest of tall trees, surrounded by oceans reminds me of good times in BC. Stunning.
I haven't followed your thread too closely so please excuse my ignorance if there’s something I’m missing about your speaker design. It may be the Omnipolar nature of the speakers in a large room with all the hard reflective surfaces, giving a wispy airy and slightly thin sound. But it might be due to just having a single 6.5” per side.
Big rooms benefit from big woofers, IME.
I once had a room with 20’ W x 30’ D with 12’ ceiling, that opened into another room:
Hard reflective surfaces everywhere. The speakers were monopole, and each had twin ported 8” RS225 woofers (Statement II, courtesy @jholtz and Curt Campbell):
And although they sounded JUST right to me, here was the in-room response, as measured by Dirac’s average of 9 point response about the listening position:
(1 speaker)
Both speakers:
Did it sound like too much bass with all that lift below 80Hz? Not at all!
I’m with Juha. It might benefit from a bit of bass lift. A monopole subwoofers behind each speaker would probably be a the quickest way to add that. (If the clients care)
PS.
My old miniDSP nanoDigi device gives up every so often. Once I thought it died. Turns out it was a DAC incompatibility (who’s heard of such a thing?! Not me!).
Plugging back the old DACs solved the issue (hint: if it ain’t broke, don’t fix it)
Other times Power cycling helps. (Hint: when it doesn’t connect to the PC)
Once I had to reflash the firmware and reload the configuration files (hint: Input meter jumps around, even without any input)
Crazy.🤪
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@Juhazi & @tktran303 -- thank you for you reminders of the Harman curve. I did realize when running those sweeps that they veered quite a bit from my preferred curves in the studio, but on music, it didn't sound as thin as it should, at least not in that final speaker position in round 2.
Thinking back about it now, the sweeps were done with a laptop via USB, and the music listening was on Jan's Qobuz & Spotify acc via the Wiim app on his smart phone -- optical between minidsp & Wiim mini. It is possible that the bass was boosted with the Wiim EQ. I neglected to check that. It would explain the discrepancy between what I heard with music and the FR curves I recorded.
I'm headed back for another visit today. Will retest & listen.
And yes, I agree 2 6.5" woofers cannot be expected to fill such a big space. Jan & Lisa don't need more than moderate volume but a visiting son, daughter, nephew might well push the system harder. I am tempted to change direction and clone one of the super well documented @hifijim systems. I have a pair of sb34 woofers sitting idle...
Will see after the next visit & assessment.
PS -- much different working in a space that's not mine. They are good friends but both mostly work from home, and I don't have luxury of hanging around for days, tinkering, listening, testing as I do in my studio. I've spent little over an hour with music on this system setup in their space. Might have to arrange get keys during their next trip away.
Thinking back about it now, the sweeps were done with a laptop via USB, and the music listening was on Jan's Qobuz & Spotify acc via the Wiim app on his smart phone -- optical between minidsp & Wiim mini. It is possible that the bass was boosted with the Wiim EQ. I neglected to check that. It would explain the discrepancy between what I heard with music and the FR curves I recorded.
I'm headed back for another visit today. Will retest & listen.
And yes, I agree 2 6.5" woofers cannot be expected to fill such a big space. Jan & Lisa don't need more than moderate volume but a visiting son, daughter, nephew might well push the system harder. I am tempted to change direction and clone one of the super well documented @hifijim systems. I have a pair of sb34 woofers sitting idle...
Will see after the next visit & assessment.
PS -- much different working in a space that's not mine. They are good friends but both mostly work from home, and I don't have luxury of hanging around for days, tinkering, listening, testing as I do in my studio. I've spent little over an hour with music on this system setup in their space. Might have to arrange get keys during their next trip away.
"It is possible that the bass was boosted with the Wiim EQ"
Very good notice! Modern pocket-size streamers and amps, let alone AVRs, have tens of eq settings and some of them are "On" as default.
I prefer Yamaha products, but despite I'm familiar with YPAO and MusicCast they give me surpsises. Each input in AVR has own settings...
For example WXC-50 has decompression enhancer, loudness eq and speaker type "bookshelf" on as default. It took me a while to go through all those for my big 3-way actives!
RXV- series and higher fortunately still have "Straight" and "Pure" buttons in remote (but not in MusicCast app)
Very good notice! Modern pocket-size streamers and amps, let alone AVRs, have tens of eq settings and some of them are "On" as default.
I prefer Yamaha products, but despite I'm familiar with YPAO and MusicCast they give me surpsises. Each input in AVR has own settings...
For example WXC-50 has decompression enhancer, loudness eq and speaker type "bookshelf" on as default. It took me a while to go through all those for my big 3-way actives!
RXV- series and higher fortunately still have "Straight" and "Pure" buttons in remote (but not in MusicCast app)
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That’s really lovely from 300hz on up……excellent work. Even if you were unable to effectively lift the response uniformly on down from here, just eliminating that suckout from 130 to 250 will warm up the presentation immensely……..that’s nearly ALL of the character of human voice in that single octave……and would be my number one priority
I’m not surprised by this measured result either……I’ve observed the same. Sims are flawed and we’ve all experienced it…..but not enough to stop treating them like blueprints for success.
It’s working very well supporting a pair of Magnepan LRS. I haven’t added DSP between the Maggie’s and their amp yet though as I need to delay the Maggie’s a few ms as they’re 30” out into the room in front of the 18’s. It works ‘ok’ as it is because I’m not high passing the Maggie’s…..only a low pass on the IB so it’s supplemental…… not perfect. After listening for a few days while we were up at the house for a week…..I don’t think I’m gonna high pass the Maggie’s still……the overlap sounds well integrated to my ears and it all meets my modest SPL requirements as is.
Take all of this with a grain of salt as far the the Maggie’s are concerned…..we know what they are…..and yet they’re sooooo much fun to listen to, I‘m just too old and set in my ways to care otherwise. As for the infinite Baffle…..well……it just doesn’t get any better……all the glory of OB without any of the restrictions…..other than the obvious hazards and complications of the install. Even with the garage door open, running the car to warm up temps in NE a February weather added a bit of an odor to the living space….I was given the ’look’ of disappointment. A solution attempt this spring is now essential……or I’ll be drywalling over some holes and licking my wounds.
Thanks for all of this……I think your pentagon design has inspired me to begin a new design based on your observations,
That's kinda cool.
Before getting immersed in the challenges of integrating this system into J & L's room, I was feeling that the Pentagon Omni Towers might be good candidates for the title of "good enough speakers for everyman". (The use of active DSP amplification notwithstanding.) Their sonic presentation in my studio was impressively rich & consistent most everywhere in the room. Easy to place, smooth, detailed, dynamic. Very listenable with all the music I threw at it.
The caveat is that my studio is much better damped than the average LR, and has a good balance of dimensions, absorption, reflection & diffusion (from shelves loaded with a variety things): 22L x 19W x 6~9'H (~3400 cubic feet)-- sloping ceiling, massive bass trap, acoustic ceiling tiles 50% reflective in mid frequencies, with 12" thickness of fiberglass between the tiles & the outer roofing. It's not a huge room but big enough, and has a central space that's acoustically open. Here's a couple pics of the room.
Right & speaker wall
Left wall
Back wall & entry. Pic taken early in the room development. Note the 8" thick recycled cotton batting up along the entire intersection of wall & ceiling. That is one huge bass trap.
Obviously a bigger space presents challenges for the 6.5" Seas drivers; realistically, my guess is that ~4000 cf is a comfortable max space for them. I need to find a typical LR to try them. J & L's place is too big, and so is mine -- my house also featrures a "great room" encompassing entry, living, dining & kitchen in one 46x23x8' space (~8500 cf).
Fine tuning these speakers for good frequency response is a breeze. There's no need for any off-axis horizontal measurements as it is essentially identical in the same horizonal plane all around the speaker. There's more variation in vertical FR, but only when closer than ~8'. Further back, I heard no significant difference between standing & sitting.
I will explore more omni designs, starting with another pentagon 2-way that's big enough for an 8' or 10" and a bit shorter, perhaps 26" instead of >30", to suit the low position of many comfy LR seats. The sound does get a bit muted when your ears are below the height of the upward facing woofer closer than ~8' horizontal distance. Candidates on hand are Dayton RS225, Peerless NE265, and Peerless SLS 8". The Dayton Audio RSS265HF-4 might be worth a try -- but only if mated to a tweeter that can be crossed as low as 1kHz. (That calls for a Scanspeak 10F; the reflector for the woofer would be large enough for perhaps a liter of air behind the 10F.)
Esp. if you use DSP, there's little reason to worry about the narrowing dispersion of larger drivers & the directivity mismatch with the tweeter. Within reason, using PEQ to adjust FR through the crossover transition range w/o increasing 3rd order harmonic is enough to correct for this. Keep the crossover frequency well below cone breakup and/or use a notch filter for that. Ditto the high end narrowing of the tweeter: If it can handle boost well, just go ahead & apply it for flat response from your standard mic measuring distances, because it will be the same in a complete circle around the speaker.
Day 3 at J & L's place.
My suspicion that the Wiim app EQ bass boost had been applied in my last music listening session on Day 2 proved correct. Listening without that boost, the bass was thinner, though surprisingly still fuller than the last set of FR curves suggest. I made some miniDSP PEQ adjustments, including a ~4dB Q=.7 low shelf at 250Hz. Total boost at 40 Hz is still just 7 dB.
That was at about 0.7m distance from the left speaker, the only one driven. After that sweep, I added a 4 dB peak Q=2.5 boost at 550Hz. I tried applying a sharper +4 dB 150Hz boost but that made music sound a touch heavy, so I expect the dip is a floor cancellation effect not readily heard.
Again, the overall presentation was good, not that different from what I recalled from day 2. Mids might have become a bit fuller, more natural.
The wispiness I mentioned before is actually my subjective reaction to the much higher level of reverberation in this big room. There aren't any nasty effects like flutter or slap echo, as the room has enough asymmetry. It is audible but not unpleasant at the nominal seating area, but does become more apparent and less pleasant further away -- beyond where the piano is in the middle.
I think I have to answer the question of whether a conventional, more directional, direct firing speaker system would reduce the reverberation effects. And whether it is preferable. Not having such a loudspeaker like that on hand, it will take a while.
My suspicion that the Wiim app EQ bass boost had been applied in my last music listening session on Day 2 proved correct. Listening without that boost, the bass was thinner, though surprisingly still fuller than the last set of FR curves suggest. I made some miniDSP PEQ adjustments, including a ~4dB Q=.7 low shelf at 250Hz. Total boost at 40 Hz is still just 7 dB.
That was at about 0.7m distance from the left speaker, the only one driven. After that sweep, I added a 4 dB peak Q=2.5 boost at 550Hz. I tried applying a sharper +4 dB 150Hz boost but that made music sound a touch heavy, so I expect the dip is a floor cancellation effect not readily heard.
Again, the overall presentation was good, not that different from what I recalled from day 2. Mids might have become a bit fuller, more natural.
The wispiness I mentioned before is actually my subjective reaction to the much higher level of reverberation in this big room. There aren't any nasty effects like flutter or slap echo, as the room has enough asymmetry. It is audible but not unpleasant at the nominal seating area, but does become more apparent and less pleasant further away -- beyond where the piano is in the middle.
I think I have to answer the question of whether a conventional, more directional, direct firing speaker system would reduce the reverberation effects. And whether it is preferable. Not having such a loudspeaker like that on hand, it will take a while.
Having another 6.5 mounted to the front face of the pentagon with a .5 coil on it for a 1st order low pass target around 500hz would make this speaker near ideal for most casual listening spaces of 120-150sq ft…..this is the direction I’ll likely take.
I can’t help but wonder what the midbass response might look like with a 15-20 degree angle to the top,firing woofer baffle much like Mirage‘s Omni systems……I bet they did some experimentation there and came up with the tilt…..would certainly help with the ceiling bounce cancellation.
I can’t help but wonder what the midbass response might look like with a 15-20 degree angle to the top,firing woofer baffle much like Mirage‘s Omni systems……I bet they did some experimentation there and came up with the tilt…..would certainly help with the ceiling bounce cancellation.