Hi all, quick update.
I'm in the process of building carts to set the big syn11s on, that are a big bass-reflex sub.
Big, like in 780 L gross, that roll around on 8" wheels, with downward firing ports.
Decommissioning my PPSL subs to move the 18"s over into the new guys. Kinda sad really, but the sound of syn11 is simply demanding i move forward.
And I cannot keep both a pair of syn11s on carts, as well as a pair of PPSL subs, all in the same room spacewise.
So i concludeth, ....since syn11 must have a cart and a sub, cart must also be a sub.
Anyway, the 18n862's are such an easy bass-reflex build.
Here's 2.83V ...without any filters.
followed by 100V with a BW3 @23Hz, and two small PEQ and high-shelf cutting filters.
It's within xmax throughout...I'd call it max available SPL.
Hope to have one built within a few days to measure out on the driveway.
After both subs are built, will build the second syn11. Got everything for it already.
Oh, I meant to post/add these previously.
Here are the CD's high section, and the mid's section, with all ports blocked, processed and in the far field. (to contrast against previous processed 'at mouth' posts.)
Low and sub (18") sections don't vary with angle so no point posting them. Can't find CD's high section, will post when do.
I'm in the process of building carts to set the big syn11s on, that are a big bass-reflex sub.
Big, like in 780 L gross, that roll around on 8" wheels, with downward firing ports.
Decommissioning my PPSL subs to move the 18"s over into the new guys. Kinda sad really, but the sound of syn11 is simply demanding i move forward.
And I cannot keep both a pair of syn11s on carts, as well as a pair of PPSL subs, all in the same room spacewise.
So i concludeth, ....since syn11 must have a cart and a sub, cart must also be a sub.
Anyway, the 18n862's are such an easy bass-reflex build.
Here's 2.83V ...without any filters.
followed by 100V with a BW3 @23Hz, and two small PEQ and high-shelf cutting filters.
It's within xmax throughout...I'd call it max available SPL.
Hope to have one built within a few days to measure out on the driveway.
After both subs are built, will build the second syn11. Got everything for it already.
Oh, I meant to post/add these previously.
Here are the CD's high section, and the mid's section, with all ports blocked, processed and in the far field. (to contrast against previous processed 'at mouth' posts.)
Low and sub (18") sections don't vary with angle so no point posting them. Can't find CD's high section, will post when do.
Ok, the saga of syn11 is deep in the sub/cart stage, that syn11 needs to sit on.
Here's the big guy under development. 46"w x 40" h x 29" deep.
Ports are downward firing, 12" sonotubes. Downward works because the wheels are 8" and give almost 10" ground clearance.
Here's something folks might appreciate (about q-sys and testing.
I'm using an ethernet network amp that has 4 mic/line inputs.
So all that's needed for remote testing is AC power and ethernet to the amp.
Test stimulus signal from soundcard travels via ethernet, as does mic capture.
I measure and tune the sub from my office maybe 150ft away. I don't even hear the sub Lol.
Anyway, here's raw and processed response. 100Hz LR 96dB/oct low pass. No high pass yet.
I've measured sensitivity at 98.5dB, 2.83v.
OK, but not great....that's just the price of wanting a true f-3 at 25Hz I guess....there's no boost there.
One thing is clear...the sonotubes have to go. They will never stand full SPL,
I'm going to build downward firing slot ports out of 3/4" birch ply, mimicking the monotubes area and length.
I know folks might be wondering what does a sub/cart have to do with a unity/syn build.....
but honestly for syn 11...everything!!!!
Big damn project
Here's the big guy under development. 46"w x 40" h x 29" deep.
Ports are downward firing, 12" sonotubes. Downward works because the wheels are 8" and give almost 10" ground clearance.
Here's something folks might appreciate (about q-sys and testing.
I'm using an ethernet network amp that has 4 mic/line inputs.
So all that's needed for remote testing is AC power and ethernet to the amp.
Test stimulus signal from soundcard travels via ethernet, as does mic capture.
I measure and tune the sub from my office maybe 150ft away. I don't even hear the sub Lol.
Anyway, here's raw and processed response. 100Hz LR 96dB/oct low pass. No high pass yet.
I've measured sensitivity at 98.5dB, 2.83v.
OK, but not great....that's just the price of wanting a true f-3 at 25Hz I guess....there's no boost there.
One thing is clear...the sonotubes have to go. They will never stand full SPL,
I'm going to build downward firing slot ports out of 3/4" birch ply, mimicking the monotubes area and length.
I know folks might be wondering what does a sub/cart have to do with a unity/syn build.....
but honestly for syn 11...everything!!!!
Big damn project
Hi Mark,
Seeing your twin 18's reminds me of the twin 12 cabinets I use in my front room. My amps are currently sitting on top of one of them and the vibration from having them both front mounted is enough at normal home levels (probably getting 60W max) that I would never build a twin sub again without doing them push push for force cancellation.
Regards,
Rob.
Seeing your twin 18's reminds me of the twin 12 cabinets I use in my front room. My amps are currently sitting on top of one of them and the vibration from having them both front mounted is enough at normal home levels (probably getting 60W max) that I would never build a twin sub again without doing them push push for force cancellation.
Regards,
Rob.
Attachments
Hi Steffen, I thought about trying to build a PPSL cart, with the drivers in a vertical orientation.
Here's some of the things that stopped me:
Giving up my PPSL subs has not been easy...as far as I've seen they are tone of the best combinations of loud, low, and clean.
But I decided since syn11 is super down to 40Hz sealed, I wanted to go lower the my PPSL's f-3 30Hz.
So I decided to shoot for 25Hz with new design.
I have a max size of 46"w (to match syn11 width), and 29" deep (to get through sliding doors to outside). Height could be anything, but damn thing is already 49" tall.
Bass reflex that size makes it to 24-25Hz. If it were a PPSL, the plenum takes up enough volume to limit sub to about 28Hz.
And down firing ports with a vertical plenum was looking tricky.
Another stopper...the weight of the new sub with syn11 on top is getting to be yikes. My smaller PPSLs probably weigh as much I expect this bigger bass-reflex to come in.
Last stopper....this simple BR is such an easier build.....and the price of birch ply is out the roof.
I hear you Rob,
I've extolled my push-push dual 18"s countless times.
Sometimes I think I'm crazy for pulling their drivers out to build these sub/carts.
It's just....the sound of syn11s, with their sealed 18"s that reach to 40Hz, along with the PPSLs low passed at 60-80Hz, is simply so good I'm trading everything in for it.
Part of the trade though, is the compromise that both syn11 on big carts, and my PPSLs subs, can't all fit.
Hence the new BR sub/carts.
One piece of encouragement for me though, is my center syn10 stack does not use a PPSL. It uses two single 18" bass-reflex stacked under the syn10.
So I'm familiar with the vibration issue potential.
I think bigger 18"s, needing less excursion that 12"s, don't have quite the the need for force cancellation. (until really cranked, when it gets worse haha)
I'm giving up the whole LCR syn10 setup with its PPSL subs and syn10 dual 18" center stack, in pursuit of stereo syn11.
Amazing really, I thought syn10 LCR was it....
And then I heard a single syn11 .... lol
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Hi Mark
Well you can still move the 18" woofers out on the sides of the sub-cart, one on each side, if it should turn out that vibration is a problem.
And just to tease you a bit: The trinaural LCR setup I heard at Uli B. was only with two full-range L and R and the C was midrange and treble only! So there is still a chance for your "homeless" SYN 10 center-speaker to sneak back into the setup! Progress never stops.
Happy building
Steffen
Well you can still move the 18" woofers out on the sides of the sub-cart, one on each side, if it should turn out that vibration is a problem.
And just to tease you a bit: The trinaural LCR setup I heard at Uli B. was only with two full-range L and R and the C was midrange and treble only! So there is still a chance for your "homeless" SYN 10 center-speaker to sneak back into the setup! Progress never stops
.Happy building
Steffen
And just to tease you a bit: The trinaural LCR setup I heard at Uli B. was only with two full-range L and R and the C was midrange and treble only! So there is still a chance for your "homeless" SYN 10 center-speaker to sneak back into the setup! Progress never stops
Hi Seffen, yeppers...progress never stops...ever, huh?! Lol
I did think about putting the 18"s on the sub-cart's sides, but passed on that too.
Because in my LCR setup, the center stack which uses 2 single 18"s, instead of PPSLs.....is my favorite sounding stack. Just has a little more visceral impact than a PPSL stack.
I built the PPSLs when I was into live sound, with the idea PPSL would stop subs from walking around at very high drive levels. And heck yeah, it works.
And it's also cool not to feel almost any vibration at less than war volume.
But the thing is, even when fully cranking my center Syn10 stack with the regular 18"s, vibration appears to be a non-issue physically or sonically.
So i'm left like always, mulling tradeoffs, hoping not to change my mind too quick.... hahaha
Oh, for a long while my LCR matrix setup did not have a center sub. All three syn10s are identical, and high-passed at 100Hz.
It was a clear improvement when I added the center subs. Maybe something Uli B might want to consider...
hi Mark
Yea, that is an ongoing discussion in that forum. Uli B. argues, that he thinks it is too offensive to look at three stacks of horns!? Well everyone chooses his own compromises I guess!?
Yea, that is an ongoing discussion in that forum. Uli B. argues, that he thinks it is too offensive to look at three stacks of horns!? Well everyone chooses his own compromises I guess!?
Update: Both "sub-carts" are built.
Finally working on 2nd syn11. I think i've built too many syns....took only about 3 hours today, to make the horn...
Anyway, here's the rig. Comes with 8" castor wheels and a 20" ball bearing spinorama in between sub and top.
Get this, my dumb a** forgot the exterior doors have have raised sill channels , because they are sliders.
So the rig is 1/2" too tall to get outside !!! Damn !!! Whole purpose has been something i can move in and out.
Oh well, 6" wheels due tomorrow.... I can be pretty dumb.....
Subs' response after converting it to slotted ports, cause the sonotubes were wimpy.
Green raw. Blue processed with 100 Hz LR 96 dB/oct low pass. Red processed with 80 Hz low pass.
Note green raw is about perfect on its own to about 45Hz...haven't seen such before.
The notch at about 110 Hz is due to the way I had to put the slot porst in. Don't really care, cuase this sub will never be used below a steep 100Hz.
With syn11, I'll probably end up low-passing it 60-70Hz.
Sonically, indoors, the directionality increase of the bass vs PPSL's off to a very close side is remarkable.
Don't really know what to think about that yet.
By far and away though, I've never heard anything quite like this. Everything literally jumps out, vocals, bass transients, simple guitar chords...top to bottom freq wise, soft of low.....
Loving it for sure....and pleasantly puzzled too.
Finally working on 2nd syn11. I think i've built too many syns....took only about 3 hours today, to make the horn...
Anyway, here's the rig. Comes with 8" castor wheels and a 20" ball bearing spinorama in between sub and top.
Get this, my dumb a** forgot the exterior doors have have raised sill channels , because they are sliders.
So the rig is 1/2" too tall to get outside !!! Damn !!! Whole purpose has been something i can move in and out.
Oh well, 6" wheels due tomorrow.... I can be pretty dumb.....
Subs' response after converting it to slotted ports, cause the sonotubes were wimpy.
Green raw. Blue processed with 100 Hz LR 96 dB/oct low pass. Red processed with 80 Hz low pass.
Note green raw is about perfect on its own to about 45Hz...haven't seen such before.
The notch at about 110 Hz is due to the way I had to put the slot porst in. Don't really care, cuase this sub will never be used below a steep 100Hz.
With syn11, I'll probably end up low-passing it 60-70Hz.
Sonically, indoors, the directionality increase of the bass vs PPSL's off to a very close side is remarkable.
Don't really know what to think about that yet.
By far and away though, I've never heard anything quite like this. Everything literally jumps out, vocals, bass transients, simple guitar chords...top to bottom freq wise, soft of low.....
Loving it for sure....and pleasantly puzzled too.
'Cute little ones' works for me
It's really funny, as massive as this combo is, it's probably the most delicate sounding speaker I've heard yet.
Really light and airy. Clarity to die for.
The low end is funny too. Incredibly strong, as one can imagine with four 18"s for a single speaker.
Two of the 18"s sealed, in the syn horn, sound different than with 18"s in outboard subs....complete pure integration with the low mids.
I think most folks would be happy with just them high passed at 40Hz.
The sub cart, easily within 1/4 WL of the 18"s in the syn horn, takes it down now to 25 Hz. I was used to 30Hz with the ppsl subs, and it does matter all too often not to reach to 30Hz, to my ears.
Latest config is to high pass the 18's in the syn horn at 50Hz, and low pass the sub-cart at 70Hz.
Xover may converge to a common xover freq, dunno.
Since I keep all driver sections on their own real-time gain controls, exact over between the sub sections doesn't matter so much, especially since both sides stay in phase despite relative level changes.
It's really cool to be able to adjust sub levels via two passbands....25-70Hz, and 50-100Hz. Never had that capability before, it's a good tool for sure.
Amazing how many recordings reflect an imbalance between "high sub" and "low sub". I guess it shows what kind of room/system the recording was made with.
It's really funny, as massive as this combo is, it's probably the most delicate sounding speaker I've heard yet.
Really light and airy. Clarity to die for.
The low end is funny too. Incredibly strong, as one can imagine with four 18"s for a single speaker.
Two of the 18"s sealed, in the syn horn, sound different than with 18"s in outboard subs....complete pure integration with the low mids.
I think most folks would be happy with just them high passed at 40Hz.
The sub cart, easily within 1/4 WL of the 18"s in the syn horn, takes it down now to 25 Hz. I was used to 30Hz with the ppsl subs, and it does matter all too often not to reach to 30Hz, to my ears.
Latest config is to high pass the 18's in the syn horn at 50Hz, and low pass the sub-cart at 70Hz.
Xover may converge to a common xover freq, dunno.
Since I keep all driver sections on their own real-time gain controls, exact over between the sub sections doesn't matter so much, especially since both sides stay in phase despite relative level changes.
It's really cool to be able to adjust sub levels via two passbands....25-70Hz, and 50-100Hz. Never had that capability before, it's a good tool for sure.
Amazing how many recordings reflect an imbalance between "high sub" and "low sub". I guess it shows what kind of room/system the recording was made with.
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I very much agree with the benefits of being able to adjust lower/upper bass. I run kick bins for my soundsystem and more than anything I like the additional control it provides for various genres. I'm not sure it's more "accurate" that way, but it is a more flexible way of doing things.
Also I think there's a difference in sound from splitting bass sections that you miss with one way cabs. The mid bass cab/passband is very musical unlike sub bass passbands which are more raw energy (imo). I like putting the upper bass higher as it adds a "cleaner" sound when up close to the speaker, and you don't get overwhelmed by sub bass. When it's a single cab it's hard to hear the finer details in the mid bass/lower midrange without getting the "bloom" interfering with our ears.
Anyway, just my 2c worth.
Also I think there's a difference in sound from splitting bass sections that you miss with one way cabs. The mid bass cab/passband is very musical unlike sub bass passbands which are more raw energy (imo). I like putting the upper bass higher as it adds a "cleaner" sound when up close to the speaker, and you don't get overwhelmed by sub bass. When it's a single cab it's hard to hear the finer details in the mid bass/lower midrange without getting the "bloom" interfering with our ears.
Anyway, just my 2c worth.
I wouldn't have been able to absorb what you are saying about lower/upper bass until now. As every thing I've built has been for sub pulling full duty from 100Hz or so, to as low as it goes.
But now, yeah I get what you're saying. The two cases I've heard clearly are when kick energy swaps out deep low energy, and vice versa.
What seems to work well for dialing in a track, is to first adjust level on the upper sub to taste, to match to the main. And then to raise the lower subs level to match up.
I guess a lot folks may cringe at the idea or real-time level adjustments for tonalities sake, but i find it immensely pleasing, and kind of fun.
But now, yeah I get what you're saying. The two cases I've heard clearly are when kick energy swaps out deep low energy, and vice versa.
What seems to work well for dialing in a track, is to first adjust level on the upper sub to taste, to match to the main. And then to raise the lower subs level to match up.
I guess a lot folks may cringe at the idea or real-time level adjustments for tonalities sake, but i find it immensely pleasing, and kind of fun.
Hi Mark
Well, when most music is mastered to sound well on most loudspeakers (monkey-coffins), which are incapable of moving air, you need to be able to adjust.
I come to think of ChrisA at the klipsch-forum (@Cask05 here), who did a lot of what he called "Demastering". He does it for a whole album in advance, you do it on the fly.
I come to think of some sort of graphic equalizer with only six bands, that does not introduce some other artifacts then level-change!
Fun to follow your journey.
Steffen
Well, when most music is mastered to sound well on most loudspeakers (monkey-coffins), which are incapable of moving air, you need to be able to adjust.
I come to think of ChrisA at the klipsch-forum (@Cask05 here), who did a lot of what he called "Demastering". He does it for a whole album in advance, you do it on the fly.
I come to think of some sort of graphic equalizer with only six bands, that does not introduce some other artifacts then level-change!
Fun to follow your journey.
Steffen
Hi Steffen, that's a great description of what gets accomplished.
I've been using independent level controls on each driver section for quite a while now, (all under the overall control of a master volume obviously).
Whenever I was tuning a new speaker build and setting up the driver-by-driver processing, it made things go much faster to have a level control on each driver section. I'd pull those level controls out of the schematic once tuning was finished.
Then one day after finishing tuning, I was lazy and left the level controls in, and then just started playing around with them during playbacks.
Eureka! Better sound, and fun.
But I got to wondering how much I might be messing up xover points and phase even though I couldn't hear anything strange.
So i set up the box I was working on at the time, some syn prior to adding small mids, and measured its acoustic response as I moved sliders up and down.
Since I use steep 96dB oct xovers, I found crossover freq doesn't move appreciably.
And with the complementarity LR linear phase xovers, phase doesn't change either.
I love it....but have yet to encounter anyone else who's tried it...so count my opinion as a sample of 1...
Here's acoustic measurements that show how phase stays intact.
The syn box was a dcx464 crossing to a 12" low mid at 650Hz.
Green is the processed trace for all three sections together.
Purple is the low section's level raised +10db, dcx mid lowered -10dB, and dcx high raised +10dB.
You can see the purple phase trace trying to peak out from under green. I'd sure call em them same
Been a while....update:
I've had the chance to listen to the pair indoors in stereo, and one outdoors in mono for quite a bit now.
I can safely say, either way, syn11 has the greatest clarity and transient response I've yet to hear in a speaker.
Outdoors on the deck, I hear details in vocals and instruments that make me run inside, and play the same track on my Stax phones to see if the details show up there too. Which they do, other than syn11 totally smokes the Stax when it comes to the sound of a kick drum or other bass transients.
The greater clarity isn't always a bed of roses though.....
On some tracks it can give a sense of being overly bright. I've run transfer functions to measure response many times, thinking a mid/hf/vhf boost or something, is going on...only to continually find that everything measures fine.
I make those response measurements because I do like to play tracks making individual drivers' levels adjustments in real time,
and sometimes the CD attenuation needed, or alternatively bass boost needed, just seems too much.
I think that degree of tonal adjustment needed comes from the horn's 75x60 degree pattern, and how low in freq it holds pattern.
About the only thing i'd do different is start with a 90x60 horn like I have with syn10.
75x60 seems like a fine racehorse chomping at the bit sometimes, compared to an easier to ride 90x60. (how's that for a crappy analogy !)
Anyway, here's the custom remote i'm currently using via qsys'
I've got it where I can save whatever level adjustments I make into presets via the remote.
Also have it where I can change how high i use the sub/cart. Presets switch FIR files on the fly, so all stays in phase.
I tried embedding a permanent house curve into processing as shown below, but found I prefer my regular flat tuning method with manual real time level adjustments, like I've always done.
It was kind cool though, the way the FIR software could span a house curve across FIR files.
That trace was for the main syn11 alone and made indoors about 1m, and not with the subcart.
(I never include a sub in indoor measurements...pointless ime. I just use outdoor ground plane processing, get it time alignmed with main and call it quits. Phase is always right once time aligned, cause phase is always flat)
Right now, the two 18" in syn11 are only covering about one octave...50-100Hz.
If i keep the sub/cart low passed at 90Hz or lower, its 18"s stay within 1/4WL c2c with the 18"s in the horn. Sound best there too.
Although outdoors, rig is a bit bass shy, if you can believe it. Needs another double 18" to keep up. So sometime I'll run the subcart up to 120Hz to compensate. But that costs the magic sound a little.
One fun and very interesting phenom for me, has been to play with just how much does low freq extion really add to music.
I ran the syn11 18"s high passed at 40Hz for a while, with the subcart band passed 25-40Hz.
All filters were 96dB/oct, so response measured basically down to 40Hz and stopped vs down to 25Hz and stopped
Surprisingly, most all music I like gains foundational body with the subcart on. But less true on older recordings.
Anyway, I painted the subcart black cause I didn't like white, and you guys know how aesthetically and WAF bound, i am ..Lol
One piece of irony is, given how much I like outdoor listening, size and weight have always been big planning factors...wanting as big as possible but still portable. Made me make all kinds of compromises through the years.
This dang setup, at somewhere between 350-400 lbs, is the easiest design/rig to move around ever...
Amazing what a set of built-in 6" castor wheels can do for portability !!!
Sorry for such a long post...hope it was a little fun at least...
I've had the chance to listen to the pair indoors in stereo, and one outdoors in mono for quite a bit now.
I can safely say, either way, syn11 has the greatest clarity and transient response I've yet to hear in a speaker.
Outdoors on the deck, I hear details in vocals and instruments that make me run inside, and play the same track on my Stax phones to see if the details show up there too. Which they do, other than syn11 totally smokes the Stax when it comes to the sound of a kick drum or other bass transients.
The greater clarity isn't always a bed of roses though.....
On some tracks it can give a sense of being overly bright. I've run transfer functions to measure response many times, thinking a mid/hf/vhf boost or something, is going on...only to continually find that everything measures fine.
I make those response measurements because I do like to play tracks making individual drivers' levels adjustments in real time,
and sometimes the CD attenuation needed, or alternatively bass boost needed, just seems too much.
I think that degree of tonal adjustment needed comes from the horn's 75x60 degree pattern, and how low in freq it holds pattern.
About the only thing i'd do different is start with a 90x60 horn like I have with syn10.
75x60 seems like a fine racehorse chomping at the bit sometimes, compared to an easier to ride 90x60. (how's that for a crappy analogy !)
Anyway, here's the custom remote i'm currently using via qsys'
I've got it where I can save whatever level adjustments I make into presets via the remote.
Also have it where I can change how high i use the sub/cart. Presets switch FIR files on the fly, so all stays in phase.
I tried embedding a permanent house curve into processing as shown below, but found I prefer my regular flat tuning method with manual real time level adjustments, like I've always done.
It was kind cool though, the way the FIR software could span a house curve across FIR files.
That trace was for the main syn11 alone and made indoors about 1m, and not with the subcart.
(I never include a sub in indoor measurements...pointless ime. I just use outdoor ground plane processing, get it time alignmed with main and call it quits. Phase is always right once time aligned, cause phase is always flat
)Right now, the two 18" in syn11 are only covering about one octave...50-100Hz.
If i keep the sub/cart low passed at 90Hz or lower, its 18"s stay within 1/4WL c2c with the 18"s in the horn. Sound best there too.
Although outdoors, rig is a bit bass shy, if you can believe it. Needs another double 18" to keep up. So sometime I'll run the subcart up to 120Hz to compensate. But that costs the magic sound a little.
One fun and very interesting phenom for me, has been to play with just how much does low freq extion really add to music.
I ran the syn11 18"s high passed at 40Hz for a while, with the subcart band passed 25-40Hz.
All filters were 96dB/oct, so response measured basically down to 40Hz and stopped vs down to 25Hz and stopped
Surprisingly, most all music I like gains foundational body with the subcart on. But less true on older recordings.
Anyway, I painted the subcart black cause I didn't like white, and you guys know how aesthetically and WAF bound, i am ..Lol
One piece of irony is, given how much I like outdoor listening, size and weight have always been big planning factors...wanting as big as possible but still portable. Made me make all kinds of compromises through the years.
This dang setup, at somewhere between 350-400 lbs, is the easiest design/rig to move around ever...
Amazing what a set of built-in 6" castor wheels can do for portability !!!
Sorry for such a long post...hope it was a little fun at least...
Hi Mark
I do very much appreciate that you take the time to produce your updates. It´s also excellent entertainment.
And yes, the sub-carts look much better in black, they almost disappear under the SYN 11!
Steffen
I do very much appreciate that you take the time to produce your updates. It´s also excellent entertainment
.And yes, the sub-carts look much better in black, they almost disappear under the SYN 11
!Steffen
^this reminds me of the following from:
https://www.diyaudio.com/community/threads/18-coax-on-open-baffle-bm18cx-38.402195/post-7436593
I'm thinking the ear canel could be changing the sound ?
also if you do find the "zinger" this way, maybe try turning off the drivers above and below the "active" driver in case we are pointing the finger at the wrong culprit.