Hi
Nice speakers !
Scottmoose: After reading the 198pages in the "Terry Cain's BIB -why does it work and does anyone have those Fostex Craft Handbooks" thread, and seeing these BIB's i think i have to try this out with the FE168Esigma. You mention a longer line (140 inch), do you have the all the internal dimention's for this design ?(think these are easy'r to convert to cm
)
How is sound compared to BackLoadedHorn ? I have a wall mounted horn with FE168Esigma, so i think i have to try this design ...
Best regards
Kim Olesen
Nice speakers !
Scottmoose: After reading the 198pages in the "Terry Cain's BIB -why does it work and does anyone have those Fostex Craft Handbooks" thread, and seeing these BIB's i think i have to try this out with the FE168Esigma. You mention a longer line (140 inch), do you have the all the internal dimention's for this design ?(think these are easy'r to convert to cm
)How is sound compared to BackLoadedHorn ? I have a wall mounted horn with FE168Esigma, so i think i have to try this design ...
Best regards
Kim Olesen
For the 168ESigma lengthend BIB:
Line length 140in
Zdriver 30.25in
internal width 7.25in
10.25in deep. Terminate internal baffle 5.125in equidistant from front, rear and floor.
Assuming 3/4in material, this will give external dimensions of 70.75in tall (inc. a base), 8.75in wide and 12.5in deep.
A monolith version? Hmm. Proportions have to be 1x4x9 for it to be a Monolith, which in the case of a cabinet ~70in tall gives you proportions better suited in terms of cabinet volume to the 8in units. We can flip it sideways of course and do something similar if we accept a different DxWxH ratio. I'd do 70in tall x 7in deep x 18in wide (external).
At this point quick explanation is useful, which I'll copy over to the main BIB thread. I was asking both Martin and Greg about flares last night, and their answers unsurprisingly coincide, and have bearing on what we're doing.
First up, Martin doesn't think that altering the overall WxD dimensions of a TQWT will make much, if any, difference to the response of the line (baffle step etc. having a far greater effect) providing the correct CSA for the pathlength is maintained. The 1:1.4142 [i.e. sqrt (2) ] Greg established is to preserve that constant cross section for a folded line with parallel walls -the bend is the bit that can mess it up a bit. For expansion at the bend to remain even, the aformentioned WxD ratio is necessary to ensure the path is equidistant from all walls, or there's a small deviation at that point, which will affect the performance of the line. Thanks Martin & GM respectively.
It seems unlikely it's going to mess the response up that much, and it probably won't be audible to be honest, but, if anyone was wondering why the 1:1.4142 is considered the ideal, that's the reason. I'll spend a while with the Sections sheets at some point over the next few days investigating what subtle differences there are.
Line length 140in
Zdriver 30.25in
internal width 7.25in
10.25in deep. Terminate internal baffle 5.125in equidistant from front, rear and floor.
Assuming 3/4in material, this will give external dimensions of 70.75in tall (inc. a base), 8.75in wide and 12.5in deep.
A monolith version? Hmm. Proportions have to be 1x4x9 for it to be a Monolith, which in the case of a cabinet ~70in tall gives you proportions better suited in terms of cabinet volume to the 8in units. We can flip it sideways of course and do something similar if we accept a different DxWxH ratio. I'd do 70in tall x 7in deep x 18in wide (external).
At this point quick explanation is useful, which I'll copy over to the main BIB thread. I was asking both Martin and Greg about flares last night, and their answers unsurprisingly coincide, and have bearing on what we're doing.
First up, Martin doesn't think that altering the overall WxD dimensions of a TQWT will make much, if any, difference to the response of the line (baffle step etc. having a far greater effect) providing the correct CSA for the pathlength is maintained. The 1:1.4142 [i.e. sqrt (2) ] Greg established is to preserve that constant cross section for a folded line with parallel walls -the bend is the bit that can mess it up a bit. For expansion at the bend to remain even, the aformentioned WxD ratio is necessary to ensure the path is equidistant from all walls, or there's a small deviation at that point, which will affect the performance of the line. Thanks Martin & GM respectively.
It seems unlikely it's going to mess the response up that much, and it probably won't be audible to be honest, but, if anyone was wondering why the 1:1.4142 is considered the ideal, that's the reason. I'll spend a while with the Sections sheets at some point over the next few days investigating what subtle differences there are.
top area...
ok so I am going to set out the internal baffle from the top of the cabinet by an amount using a small hunk of wood.
the reason to do this is to take away the coming to a point thingy, and because I have to, as I (personally) build stricty in metric, and 5x5s of 18mm birch is the wood of my choice. so I need to extend the top to some extent, to give the horn its intended length. this I will do with nessie style panels at the horn mouth.
in order to give the space above the driver its intended area, I am supposing that I need to set it out somewhat from the baffle at the top, as it will be unable to be attached to the REAL top of the cabinet by any simple means, other than by doubling the inside of the mouth extenders, and that is unelegant and unnecessary, I think.
so I am assuming that as long as I have the same, or slightly greater (because bigger is better...) area in the space above the driver, that I am still in the bassssssss? I am gonna dig into my weathered mind to retrieve the days I used to ace the math sections on SATs. to get that triangular area thing. 1/2b*h? oh yeah, right angle triangle is like half a rectangle, which IS w*h. then I need to figure out the area of the extended form by separating it into a smaller rectangle and a right triange, DOY! dang, I have been in college too long!!!
I have a ton of pictures from projects over the years saved up...except the ones where I humorously and educationally documented the construction of the fe166es-r BIB (which incidentally works quite well in the HUGE room it is now in). those pictures were deleted by my dumb friends to make space for pictures of drunk people at a party. I have forgiven him... barely... and yes these 168ezs will be VERY well documented. Ill try to do the educational thing, regarding gluing, de-warping, and religion. if I have the time. I need to get a personal website!
yup, those are my new paramours and foreplay in the photo. purpleheart/birdseye bases, 45s here we come!
well, later y'all we might need to redirect this thread. sorry for diverting it(!)
Clark
ok so I am going to set out the internal baffle from the top of the cabinet by an amount using a small hunk of wood.
the reason to do this is to take away the coming to a point thingy, and because I have to, as I (personally) build stricty in metric, and 5x5s of 18mm birch is the wood of my choice. so I need to extend the top to some extent, to give the horn its intended length. this I will do with nessie style panels at the horn mouth.
in order to give the space above the driver its intended area, I am supposing that I need to set it out somewhat from the baffle at the top, as it will be unable to be attached to the REAL top of the cabinet by any simple means, other than by doubling the inside of the mouth extenders, and that is unelegant and unnecessary, I think.
so I am assuming that as long as I have the same, or slightly greater (because bigger is better...) area in the space above the driver, that I am still in the bassssssss? I am gonna dig into my weathered mind to retrieve the days I used to ace the math sections on SATs. to get that triangular area thing. 1/2b*h? oh yeah, right angle triangle is like half a rectangle, which IS w*h. then I need to figure out the area of the extended form by separating it into a smaller rectangle and a right triange, DOY! dang, I have been in college too long!!!
I have a ton of pictures from projects over the years saved up...except the ones where I humorously and educationally documented the construction of the fe166es-r BIB (which incidentally works quite well in the HUGE room it is now in). those pictures were deleted by my dumb friends to make space for pictures of drunk people at a party. I have forgiven him... barely... and yes these 168ezs will be VERY well documented. Ill try to do the educational thing, regarding gluing, de-warping, and religion. if I have the time. I need to get a personal website!
yup, those are my new paramours and foreplay in the photo. purpleheart/birdseye bases, 45s here we come!
well, later y'all we might need to redirect this thread. sorry for diverting it(!)
Clark
Attachments
I have high ceilings like in your picture (lovely job btw)… you don’t feel a sub or a little extra bass is necessary in your setup?
I am trying to determine if a sub or an amp upgrade would best solve my slightly light bass issue… does the SI Super T amp provide deeper bass than the original $30 amp?
Peace.
Godzilla
PS… I might simply be looking for another excuse to buy/build a powered subwoofer ;-)
I am trying to determine if a sub or an amp upgrade would best solve my slightly light bass issue… does the SI Super T amp provide deeper bass than the original $30 amp?
Peace.
Godzilla
PS… I might simply be looking for another excuse to buy/build a powered subwoofer ;-)
I reckon I'd go with this Jeff: http://www.diyparadise.com/charlize.html Bit more work, but it has a hell of a reputation. I think Dan's used them & likes them a lot. Also available in box via same place. Not too pricy either. My feeling is it's your existing amp that's the problem as, good as the little Ts are, they're very bass-light. 30db down by 40Hz or some-such I recall.
Before spending any money, why not haul one of your other amps (I think you said you've a valve amp?) to the office for the day? Bit of a pain I know, but a whole lot cheaper than spending where you don't need to. If they start thundering (as they should) then you'll know for certain it's the amp. If they're still light, then it's the room, and a sub might be an idea. My money is still on it being the amp. The little SI T-amp is good, but it ain't that good!
Clark -PM dispatched to you (or it will be in about 5 minutes )
Cheers
Scott
Before spending any money, why not haul one of your other amps (I think you said you've a valve amp?) to the office for the day? Bit of a pain I know, but a whole lot cheaper than spending where you don't need to. If they start thundering (as they should) then you'll know for certain it's the amp. If they're still light, then it's the room, and a sub might be an idea. My money is still on it being the amp. The little SI T-amp is good, but it ain't that good!
Clark -PM dispatched to you (or it will be in about 5 minutes
) Cheers
Scott
>>> Before spending any money, why not haul one of your other amps (I think you said you've a valve amp?) to the office for the day?
Thanks Scott, that’s the current plan! I have a lovely Cary tube amp that is warm and lush. NOW I have a reason to hook it up to the BIBs (and my PC… which will be a fun and interesting combination). I’ve already replaced the Cary with an SI amp at home (I have 3 just for the heck of it but one is out on lend to a friend)… so I can bring the Cary to the office. Hope it’s safe to leave an expensive tube amp overnight??? I’d be sad if it were to go missing (doubt the cleaning crew would be interested in it tho)… or get broken. The amp only weighs 40 pounds vs the BIBs at 80 pounds each.
So I am planning out the space behind my desk to put a tube amp next to my IBM pc… A fun way to play for a bit! This will also give me a chance to really hear what’s missing with the SI amp in the bass and everywhere else. Thirty vs thirteen hundred! Let’s see which sounds better?!?
Peace,
Godzilla
Thanks Scott, that’s the current plan! I have a lovely Cary tube amp that is warm and lush. NOW I have a reason to hook it up to the BIBs (and my PC… which will be a fun and interesting combination). I’ve already replaced the Cary with an SI amp at home (I have 3 just for the heck of it but one is out on lend to a friend)… so I can bring the Cary to the office. Hope it’s safe to leave an expensive tube amp overnight??? I’d be sad if it were to go missing (doubt the cleaning crew would be interested in it tho)… or get broken. The amp only weighs 40 pounds vs the BIBs at 80 pounds each.
So I am planning out the space behind my desk to put a tube amp next to my IBM pc… A fun way to play for a bit! This will also give me a chance to really hear what’s missing with the SI amp in the bass and everywhere else. Thirty vs thirteen hundred! Let’s see which sounds better?!?
Peace,
Godzilla
Let's hope the Cary if only so you don't go home crying into your beermug / green tea cup about the state the world has got itself into when a $30 toy blows a high-end piece of hardware into the weeds. With all possible respect to the SI T-amp though, which is a remarkable thing for the money, I doubt you'll have a David / Goliath problem in this case. SI T-amp takes on monster valve amp. T-amp gets its posterior whipped. The end. It's a mini adventure.
Oh yes -when you fire up the BIBs on the end of the valves, remember to stay lurking behind your desk. I have this funny feeling you might be in for a surpise. If you really want to give them a workout, slap on 'Nothing Else Matters' from Metallica's live S&M album with the SF Symphony Orchestra. This is The Torture Track to end all torture tracks. If they can deliver the weight this has in the lower registers, you've officially Arrived.
Cheers
Scott
With all possible respect to the SI T-amp though, which is a remarkable thing for the money, I doubt you'll have a David / Goliath problem in this case. SI T-amp takes on monster valve amp. T-amp gets its posterior whipped. The end. It's a mini adventure. Oh yes -when you fire up the BIBs on the end of the valves, remember to stay lurking behind your desk. I have this funny feeling you might be in for a surpise. If you really want to give them a workout, slap on 'Nothing Else Matters' from Metallica's live S&M album with the SF Symphony Orchestra. This is The Torture Track to end all torture tracks. If they can deliver the weight this has in the lower registers, you've officially Arrived.
Cheers
Scott
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