This thread is immortal 🙂
Sorry for that. You have lost 8 years of BiB bliss 🙂
Did you calculate those measurements with any of the BiB calculators that are around here? (you can find links to some of them in a post by GM in the previous page).
Given those BiB dimensions, they will be well ceiling-loaded. GM had calculated once that less than 90 cm from the BiB terminus to the ceiling would provide a good loading. I have a couple BiBs with Fostex FE166E into them, that are about the same dimensions you got and they work great. Corner loading is however a lot better than only back wall loading.
Gaston
BIB calculators here. I believe these are the best versions. If not, please email what you think is better so I can include it on the site.
https://speakerprojects.wordpress.com/cabinet-types/bib-loudspeakers/bib-calculator/
My Fostex 165k BIBs were left in the basement for my boys as per the divorce. I still have the Fostex 127e BIBs and really enjoy thier sound but they are disconnected until I find a suitable home (corners) for them.
Trial is next week - unless it gets adjourned for the third time over the past 4 years!
https://speakerprojects.wordpress.com/cabinet-types/bib-loudspeakers/bib-calculator/
My Fostex 165k BIBs were left in the basement for my boys as per the divorce. I still have the Fostex 127e BIBs and really enjoy thier sound but they are disconnected until I find a suitable home (corners) for them.
Trial is next week - unless it gets adjourned for the third time over the past 4 years!
Bummer, adjourned or postponed? A buddy has been repeatedly rescheduled WRT his young daughter for close to two years now allegedly due to the courts being overloaded with murders, rape, child abuse, etc..
Regardless, good luck!
GM
Regardless, good luck!
GM
I must admit that I didn't expect replies so quickly. I did use the calculator quoted by Godzilla I changed the dimensions slightly (to make them a little larger and taller for the large room and to fit where they will stand) but not too much...If it's not a good idea to deviate I won't.
I have been reading this thread and other sources for some time now and landed on the BIB as a good upgrade, where I used to live my living room was small 4 x5m so the ML TL were suitable and I must say they still sound pretty good.
As for my system it's mostly vinyl based, I use a 300b Music Angel which I got for £120 on EBay in 2006. I have replaced all the valves and one day will upgrade it as per Lampizator:
Music Angel 300B
But this isn't an amp thread so I won't get into that now, I did look at open baffles but I think for my current set up the BIB should be very good.
Anyhow thanks for the replies, for me I think the slightly larger dimensions should be okay but if I should stick to the calculator I will. Also they will not be in corners but against the wall opposite the sofa.
Cheers, Iain
I have been reading this thread and other sources for some time now and landed on the BIB as a good upgrade, where I used to live my living room was small 4 x5m so the ML TL were suitable and I must say they still sound pretty good.
As for my system it's mostly vinyl based, I use a 300b Music Angel which I got for £120 on EBay in 2006. I have replaced all the valves and one day will upgrade it as per Lampizator:
Music Angel 300B
But this isn't an amp thread so I won't get into that now, I did look at open baffles but I think for my current set up the BIB should be very good.
Anyhow thanks for the replies, for me I think the slightly larger dimensions should be okay but if I should stick to the calculator I will. Also they will not be in corners but against the wall opposite the sofa.
Cheers, Iain
Not a problem, BIB means just that, so hard to make it too big, just a point of diminishing returns.
That said, if you needed some baffle step compensation [BSC], then you'll probably need at least as much for the BIB.
BTW, what driver specs did you use?
GM
That said, if you needed some baffle step compensation [BSC], then you'll probably need at least as much for the BIB.
BTW, what driver specs did you use?
GM
As a total newbie, I am wondering about when does something hold well? And how much strength is necessary? I am planning to build some boxes in the near future, and of birch plywood so of course I became curious about this issue. I also happened to have a paper "Holding strenght of screws in plywood and oriented strandboard", Yusuf Z. Erdil et. al, 2002, Forest Products Journal 52(6): 55-62.
There are several factors affecting the holding strength in plywood edges. Nr. of plies, pilot hole diameter, screw size and penetration depth. They tested the withdrawal strenght to estimate the holding strength measured in lb. The highest number I found within the given parameters was 935 lb (4156.08N). This was for edge withdrawal in 5-ply, structural sheating, Southern pine, screw 12AB, pilot hole size 7/64". Pilot holes when screwing in edges is mandatory to avoid delamination. To me that sounds like a pretty high holding strength, but what do I know? Any more light on this issue would be very welcome.
The operative words here is the implied 'correct' [selection] and not noted/implied correct torquing, of said pilot holes, screws, which the casual DIYer isn't going to be bothered with, assuming they even have a clue about such things.
WRT long term acoustic pressure on the speaker joints, about all I can remember is that one of the math 'whiz kids' worked out some pressures of what was back in the '90s some extreme examples of sealed/vented alignments and the math implied that duct taped joints would suffice, which actually had been proven true decades earlier by many folks that built cabs and even fairly large horns out of cardboard or Celotex insulation panels held together with packing tape, though today's much higher Xmax power handling alignments might actually require properly mechanically clamped joints and of course some sort of sealing material unless enough screws are used to ensure a tight seal.
Obviously, for consumer and especially prosound apps, the joints must be strong enough to withstand a lot of transportation/installation abuse, but DIYers who know how to do things the right way a lot of construction 'shortcuts' can be safely used.
There are exceptions though, duct vents and especially compression horn throats must be very rigid, airtight to work properly.
In a similar vein, a major key to a good performing cab is to tie all six sides together to keep it from 'breathing' even a tiny amount as it can audibly reduce a driver's already abysmal acoustic efficiency. This in turn increases joint pressure, so it's a good plan to use some form of continuous sealer [usually some type of adhesive] regardless of how they are clamped together.
GM
WRT long term acoustic pressure on the speaker joints, about all I can remember is that one of the math 'whiz kids' worked out some pressures of what was back in the '90s some extreme examples of sealed/vented alignments and the math implied that duct taped joints would suffice, which actually had been proven true decades earlier by many folks that built cabs and even fairly large horns out of cardboard or Celotex insulation panels held together with packing tape, though today's much higher Xmax power handling alignments might actually require properly mechanically clamped joints and of course some sort of sealing material unless enough screws are used to ensure a tight seal.
Obviously, for consumer and especially prosound apps, the joints must be strong enough to withstand a lot of transportation/installation abuse, but DIYers who know how to do things the right way a lot of construction 'shortcuts' can be safely used.
There are exceptions though, duct vents and especially compression horn throats must be very rigid, airtight to work properly.
In a similar vein, a major key to a good performing cab is to tie all six sides together to keep it from 'breathing' even a tiny amount as it can audibly reduce a driver's already abysmal acoustic efficiency. This in turn increases joint pressure, so it's a good plan to use some form of continuous sealer [usually some type of adhesive] regardless of how they are clamped together.
GM
Corrections for SET amps and cabinet flexibility
Greg/Scott/Zilla/everyone,
What a great thread. Going on 10 years old.
and I read it. some parts more than once.
But before I put saw to wood,
Currently, I have some BK-16 speakers (BLH madisound kit) and have used both Fostex FE166E and FE166EN with a Bottlehead S.E.X. amp (SET, 2 watts). and I am ready to go BIB. So, I want to make sure I am allowing for the higher effective Q with the SET and have a cabinet that will work with the FF165WK and possibly the FE168EZ drivers for future options.
Numbers:
FE166E
Fs - 50Hz
Vas - 1.59
Qts - 0.21
Xmax - 0.6mm
FE166En
Fs - 53Hz
Vas - 1.31
Qts - 0.25
Xmax - 1.0mm
FF165WK
Fs - 50Hz
Vas - 0.982
Qts - 0.34
Xmax - 1.85mm
FE168EZ
Fs - 51Hz
Vas - 0.84
Qts - 0.26
Xmax - 1.6mm
Reading the bottlehead forums, PJ says figure 30 to 50% increase in Q when using there gear.
So what would be some good numbers to use when calculating a box that will work for the four Fostex drivers listed above. The FE166e, FE166en, an FF165WK are relatively close. Will I be too big for the FE168EZ if I decide to go that route down the road. I ran some numbers on the BIB calculator, but not sure what might be a good size.
The room has 9' ceilings and the speakers will be against a wall and near a corner or possible in the corners.
thanks,
Greg/Scott/Zilla/everyone,
What a great thread. Going on 10 years old.
and I read it. some parts more than once.
But before I put saw to wood,
Currently, I have some BK-16 speakers (BLH madisound kit) and have used both Fostex FE166E and FE166EN with a Bottlehead S.E.X. amp (SET, 2 watts). and I am ready to go BIB. So, I want to make sure I am allowing for the higher effective Q with the SET and have a cabinet that will work with the FF165WK and possibly the FE168EZ drivers for future options.
Numbers:
FE166E
Fs - 50Hz
Vas - 1.59
Qts - 0.21
Xmax - 0.6mm
FE166En
Fs - 53Hz
Vas - 1.31
Qts - 0.25
Xmax - 1.0mm
FF165WK
Fs - 50Hz
Vas - 0.982
Qts - 0.34
Xmax - 1.85mm
FE168EZ
Fs - 51Hz
Vas - 0.84
Qts - 0.26
Xmax - 1.6mm
Reading the bottlehead forums, PJ says figure 30 to 50% increase in Q when using there gear.
So what would be some good numbers to use when calculating a box that will work for the four Fostex drivers listed above. The FE166e, FE166en, an FF165WK are relatively close. Will I be too big for the FE168EZ if I decide to go that route down the road. I ran some numbers on the BIB calculator, but not sure what might be a good size.
The room has 9' ceilings and the speakers will be against a wall and near a corner or possible in the corners.
thanks,
cabinet joints
There are several ways to make strong, airtight speaker cabinet joints. It mainly depends on the look you want and the tools you have available.
Two methods I have used are;
Tongue and groove.
I use a handheld router with a guide fence on it to make grooves in the side panels where the front, back, and inside pieces will go. It is spaced in 1/2 the thickness of the plywood, it's width is 1/2 the thickness of the plywood, and it's depth is also 1/2 the thickness of the plywood.
The front, back, and inside panels are cut wider than the final inside dimension by an amount equal to the plywood thickness. They are cut on a table saw to make the tongues on both sides. My first picture shows a FH3 side panel with the grooves in it.
This method makes a very modern style cabinet look.
Corner block.
Here I use solid wood corner blocks to hold the edges of the plywood also using tongue and groove joints. The picture shows my Pensil cabinets with angled front blocks and "stick and dowel" side bracing.
This also is a very strong joint and makes a more traditional style "Frame and Panel" look on your speakers.
This method is also very good for MDF or flakeboard cabinets. I have made test cabinets from cheap flakeboard and cut down construction pine for the corner blocks. That made surprisingly strong cabinets considering the materials used.
There are many other ways to make joints for your cabinets. The main difference from standard furniture is that the joints should be airtight and the panels should be strong enough so they do not resonate. Pick a method that works for the tools you have and your skill level. A simple joint done well is better than a complex joint done poorly. If in doubt, make test joints using scrap materials. I do that a lot and it saves me from making expensive mistakes.
There are several ways to make strong, airtight speaker cabinet joints. It mainly depends on the look you want and the tools you have available.
Two methods I have used are;
Tongue and groove.
I use a handheld router with a guide fence on it to make grooves in the side panels where the front, back, and inside pieces will go. It is spaced in 1/2 the thickness of the plywood, it's width is 1/2 the thickness of the plywood, and it's depth is also 1/2 the thickness of the plywood.
The front, back, and inside panels are cut wider than the final inside dimension by an amount equal to the plywood thickness. They are cut on a table saw to make the tongues on both sides. My first picture shows a FH3 side panel with the grooves in it.
This method makes a very modern style cabinet look.
Corner block.
Here I use solid wood corner blocks to hold the edges of the plywood also using tongue and groove joints. The picture shows my Pensil cabinets with angled front blocks and "stick and dowel" side bracing.
This also is a very strong joint and makes a more traditional style "Frame and Panel" look on your speakers.
This method is also very good for MDF or flakeboard cabinets. I have made test cabinets from cheap flakeboard and cut down construction pine for the corner blocks. That made surprisingly strong cabinets considering the materials used.
There are many other ways to make joints for your cabinets. The main difference from standard furniture is that the joints should be airtight and the panels should be strong enough so they do not resonate. Pick a method that works for the tools you have and your skill level. A simple joint done well is better than a complex joint done poorly. If in doubt, make test joints using scrap materials. I do that a lot and it saves me from making expensive mistakes.
Attachments
If they can tell you this, then they can tell you what the amp's output impedance [series resistance] is, then add another 1/2 ohm for wiring losses = 'Rs' and use this calculator to find the driver's published [or measured] effective Qts to plug into the BIB calculator: mh-audio.nl - Home
If it's just too large for the space/whatever, then build it as big as practical and 'it is what it is' WRT potential bass output.
Also, with 9 ft ceilings, consider adding a simple gasketed 'tophat' extension to get the terminus within ~1 ft of the ceiling. That, or make the panels taller and use the shorter design's divider baffle.
GM
Greg,
I broke down and put pen to paper and got the revised Qts. It raised them it from 33% to 39% depending on the driver. I used a common 50Hz for Fs on the BiB calculator. Vb's are as follows.
FE166E - 6.535
FE166En - 6.553
FF165WK - 7.623
FE168EZ - 4.55
So both the FE166E and FE166En which I currently have are pretty much interchangeable (assuming Fs of 50Hz). and the FF165WK is bigger, but I probably not out of the range if I wanted to go that route. But what about the FE168EZ. What are the potential problems of trying that driver in this box, if I can talk Santa or someone into buying them? and along those lines what are the potential problems of running these 36% larger box with a non SET amp?
Family schedule permitting I would like to buy and cut the wood this 4th of July weekend. 😎
In response to the tophat suggestion, I don't think that will be a problem with my wife. She likes the idea that these speakers are columns that should be placed against the wall or in the corner. She wants them decorated with crown moulding and possibly paint to match the room color. When I mentioned 8 ft tall she did not seem bothered. That might change when she sees the wood cut. 😎
thanks for the help,
I broke down and put pen to paper and got the revised Qts. It raised them it from 33% to 39% depending on the driver. I used a common 50Hz for Fs on the BiB calculator. Vb's are as follows.
FE166E - 6.535
FE166En - 6.553
FF165WK - 7.623
FE168EZ - 4.55
So both the FE166E and FE166En which I currently have are pretty much interchangeable (assuming Fs of 50Hz). and the FF165WK is bigger, but I probably not out of the range if I wanted to go that route. But what about the FE168EZ. What are the potential problems of trying that driver in this box, if I can talk Santa or someone into buying them? and along those lines what are the potential problems of running these 36% larger box with a non SET amp?
Family schedule permitting I would like to buy and cut the wood this 4th of July weekend. 😎
In response to the tophat suggestion, I don't think that will be a problem with my wife. She likes the idea that these speakers are columns that should be placed against the wall or in the corner. She wants them decorated with crown moulding and possibly paint to match the room color. When I mentioned 8 ft tall she did not seem bothered. That might change when she sees the wood cut. 😎
thanks for the help,
The BIB's math intentionally makes them too large per T/S to account for some damping/wiring losses, though not nearly as much as I prefer/did way back when I was making mostly built-in [mid]bass [<500 Hz XO point] Voigt pipe corner horns or would do today if I were to make any 'FR' variants, so in your situation I'd build the biggest figuring that if adding series resistance and/or extra damping altered the speaker's 'tone' too much, then it's simple enough to reduce the pipe's final expansion to 'tone' it down, just set it up internally to be able to Velcro on some additional sheetrock or similarly cheap, low resonance panels.
She 'sounds' like a 'keeper' to me 😉! I never had any problems with any of mine or others SWMBO, so was rather shocked at how so many on-line around the world suffer[ed] from WAF/SAF/SO issues, but then I included them in the project, so most of the systems were either painted and/or stained and/or wallpapered and/or crown/base molded by them [sometimes with my help] to blend in as much as practical.
My fave, and wish I still had photos of them to post, were some free standing 7 ft tall Roman column speakers that the owner painted to make them look like pink veined marble [she was an illustrator/ portrait painter by trade]. They looked so good that it got her a contract to 'marbleize' a local Mall's storefront except in black/white vein.
Anyway, good luck with it and looking forward to some finished pics, thoughts on performance and what all fine tuning was required. Note that when it comes to voicing a 'FR' [single or multi-way] speaker, especially for live recordings, female hearing in general and youthful [undamaged] in particular is better overall than men's IME and of course if voiced using their music, then success is pretty much ensured 😉.
GM
She 'sounds' like a 'keeper' to me 😉! I never had any problems with any of mine or others SWMBO, so was rather shocked at how so many on-line around the world suffer[ed] from WAF/SAF/SO issues, but then I included them in the project, so most of the systems were either painted and/or stained and/or wallpapered and/or crown/base molded by them [sometimes with my help] to blend in as much as practical.
My fave, and wish I still had photos of them to post, were some free standing 7 ft tall Roman column speakers that the owner painted to make them look like pink veined marble [she was an illustrator/ portrait painter by trade]. They looked so good that it got her a contract to 'marbleize' a local Mall's storefront except in black/white vein.
Anyway, good luck with it and looking forward to some finished pics, thoughts on performance and what all fine tuning was required. Note that when it comes to voicing a 'FR' [single or multi-way] speaker, especially for live recordings, female hearing in general and youthful [undamaged] in particular is better overall than men's IME and of course if voiced using their music, then success is pretty much ensured 😉.
GM
>>> So, I want to make sure I am allowing for the higher effective Q with the SET and have a cabinet that will work with the FF165WK and possibly the FE168EZ drivers for future options.
Personally, I'd build the biggest BIB if it fits your room and your wife agrees and use any of the drivers. I have the 168z (older style with whizzer) and compared it to the 165k (the older white coned one) and preferred the cheaper driver overall.
The hole may be the same but where the screws go is not the same for the Sigma drivers. Also consider the build behind the driver and make sure you have enough room.
Enjoy the build! Once built, it will be in your house for a long time.
Personally, I'd build the biggest BIB if it fits your room and your wife agrees and use any of the drivers. I have the 168z (older style with whizzer) and compared it to the 165k (the older white coned one) and preferred the cheaper driver overall.
The hole may be the same but where the screws go is not the same for the Sigma drivers. Also consider the build behind the driver and make sure you have enough room.
Enjoy the build! Once built, it will be in your house for a long time.
Taller is better?
Greg,
I bought my plywood yesterday. 23/32" 11 ply "pine" plywood. It looks like birch to me, but he insisted it was pine. Plus the price was right. $35 a sheet.
From a build and finish standpoint, it would be easier to make the side panels 8' and use the shorter design's divider baffle at its 68" height location. Easier than making the box 68" tall and then work on the top hat extension and blending and attaching them. The 8' panels make an effective 28" top hat extension. Am I going to create any major problems with doing this? Does this lower the designed Fs of the box? I am designing for 50 Hz.
thanks and Happy Fourth of July!
Greg,
I bought my plywood yesterday. 23/32" 11 ply "pine" plywood. It looks like birch to me, but he insisted it was pine. Plus the price was right. $35 a sheet.
From a build and finish standpoint, it would be easier to make the side panels 8' and use the shorter design's divider baffle at its 68" height location. Easier than making the box 68" tall and then work on the top hat extension and blending and attaching them. The 8' panels make an effective 28" top hat extension. Am I going to create any major problems with doing this? Does this lower the designed Fs of the box? I am designing for 50 Hz.
thanks and Happy Fourth of July!
Hmm, it probably has voids in it, so hope you don't hear/perceive any strange noises in the background.
No, it's the way I'd build it with 8 ft lengths.
Yes, it will lower tuning, but it will also be larger, so more acoustic loading.
Technically, drivers can be tuned all the way down to [Fs*effective Qts/2], so unless the driver's effective Qts is quite high it can be tuned quite low and with even simple pipe horn loading, there's usually enough efficiency if hard up against a wall, and especially when corner loaded, to have adequate power handling for all music, though of course not loud enough for a serious HT apps with LFE content that can be down to near Dc, but you might be surprised at how much 'sub' rumble even a small driver can generate; enough to have neighbors pounding on your door if nearby.
I never built any pipe horns with <8" drivers and they were always corner loaded, but folks usually swore there was at least one 15" woofer behind its grill cloth and from two to four low Fs ones when there was one.
GM
No, it's the way I'd build it with 8 ft lengths.
Yes, it will lower tuning, but it will also be larger, so more acoustic loading.
Technically, drivers can be tuned all the way down to [Fs*effective Qts/2], so unless the driver's effective Qts is quite high it can be tuned quite low and with even simple pipe horn loading, there's usually enough efficiency if hard up against a wall, and especially when corner loaded, to have adequate power handling for all music, though of course not loud enough for a serious HT apps with LFE content that can be down to near Dc, but you might be surprised at how much 'sub' rumble even a small driver can generate; enough to have neighbors pounding on your door if nearby.
I never built any pipe horns with <8" drivers and they were always corner loaded, but folks usually swore there was at least one 15" woofer behind its grill cloth and from two to four low Fs ones when there was one.
GM
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GM,
Greetings!
With reference to the formula you shared above on driver tuning, may we explore an example for a ~5.5 inch driver:
Fs=40 Hz
Qts= .40
Vas=~30 liters
So tuning for this driver can go as low as:
=FS*effective Qts/2
=40*0.40/2
= 40*0.2
=8 Hz
That is seriously low... wouldn't Xmax, distortion etc come into play? Am I making a big error somewhere? 🙂
Of course, and why acoustic efficiency must increase 4x/octave if you want a ~flat response at a driver's base efficiency, so boundary, room gain is a must if a stupendously large horn or multiple speaker arrays isn't an option.
WRT distortion though, our lack of hearing acuity down low allows us to enjoy LFE in acoustically small enclosed spaces, otherwise AFAIK, none of us would need speakers that had any appreciable output below ~125 Hz with a cut-off at a human's lowest fundamental around 60 Hz; so once the 'dreaded' high group delay that increases with decreasing frequency is shifted low enough it becomes a non issue since higher up in frequency it has decayed enough to be as low, or lower [in theory], than a transient perfect sealed alignment except with more usable gain BW with a perceived superior SQ thanks to our generally poor hearing acuity compared to most [all?] of the rest of the 'animal' kingdom.
GM
WRT distortion though, our lack of hearing acuity down low allows us to enjoy LFE in acoustically small enclosed spaces, otherwise AFAIK, none of us would need speakers that had any appreciable output below ~125 Hz with a cut-off at a human's lowest fundamental around 60 Hz; so once the 'dreaded' high group delay that increases with decreasing frequency is shifted low enough it becomes a non issue since higher up in frequency it has decayed enough to be as low, or lower [in theory], than a transient perfect sealed alignment except with more usable gain BW with a perceived superior SQ thanks to our generally poor hearing acuity compared to most [all?] of the rest of the 'animal' kingdom.
GM
wood is cut
So I have my wood cut to widths. Everything is 8 ft long. I will use the inner baffle board to also make the bottom.
The plywood is 11 ply and yes it has some voids, but I figure a void on one layer out of 11 is better than a void on one layer out of five. I think it is considered cabinet grade pine plywood. But it does look like birch on the outer layers. Also I will be trimming them out and adding some thickness to all sides. Hopefully resonance is not an issue.
That said it may take some time to get the boxes built. It looks like a busy month. and I have 3 children, 7, 5, and 5 months. Hopefully I can work on the build of a speaker in the evenings a couple nights a week. I went from 3 sheets of plywood in the front room (where my stereo is) to a stack of cut boards in the front room. Yes my wife is a keeper.
thanks for the answers Greg. Pictures will follow, just not sure when. 😎
So I have my wood cut to widths. Everything is 8 ft long. I will use the inner baffle board to also make the bottom.
The plywood is 11 ply and yes it has some voids, but I figure a void on one layer out of 11 is better than a void on one layer out of five. I think it is considered cabinet grade pine plywood. But it does look like birch on the outer layers. Also I will be trimming them out and adding some thickness to all sides. Hopefully resonance is not an issue.
That said it may take some time to get the boxes built. It looks like a busy month. and I have 3 children, 7, 5, and 5 months. Hopefully I can work on the build of a speaker in the evenings a couple nights a week. I went from 3 sheets of plywood in the front room (where my stereo is) to a stack of cut boards in the front room. Yes my wife is a keeper.
thanks for the answers Greg. Pictures will follow, just not sure when. 😎
You're welcome!
Cabinet grade isn't too bad unless there's any loose plugs in the lams to excite, then short of finding/fixing it, it will eventually get on your 'last nerve', though considering your quantity of kids/ages, I imagine you're pretty much numb to such distractions by now. 😉
GM
Cabinet grade isn't too bad unless there's any loose plugs in the lams to excite, then short of finding/fixing it, it will eventually get on your 'last nerve', though considering your quantity of kids/ages, I imagine you're pretty much numb to such distractions by now. 😉
GM