Thanks For Saving Me
quote:
Originally posted by BenjaminWebber
GM, could you expound a little more.
'Expound' in what way? I haven't used the 'Edge', much less compared it with real world measurements, but considering who designed it I imagine it's theoretically correct, which is about all one can reasonably expect from a sim, so it can be used to to see how moving the driver across the BIB baffle affects it internally or externally, though I assume it won't do both at the same time, ergo a certain amount of interpretation on your part is required to 'see' the summed effect.
That said, unless a cab is wide enough for its wall's eigenmodes to be down in its BW, then offsetting a driver is a waste of time since the internal wall damping will quell them, so concentrating on getting the external baffle size/shape and driver offset right is all that matters.
GM
I went back to The Edge to see what happens if you move the driver the way I had considered doing. I decided to leave the driver centered in the inner cabnet.
Sincerely,
Benjamin
quote:
Originally posted by BenjaminWebber
GM, could you expound a little more.
'Expound' in what way? I haven't used the 'Edge', much less compared it with real world measurements, but considering who designed it I imagine it's theoretically correct, which is about all one can reasonably expect from a sim, so it can be used to to see how moving the driver across the BIB baffle affects it internally or externally, though I assume it won't do both at the same time, ergo a certain amount of interpretation on your part is required to 'see' the summed effect.
That said, unless a cab is wide enough for its wall's eigenmodes to be down in its BW, then offsetting a driver is a waste of time since the internal wall damping will quell them, so concentrating on getting the external baffle size/shape and driver offset right is all that matters.
GM
I went back to The Edge to see what happens if you move the driver the way I had considered doing. I decided to leave the driver centered in the inner cabnet.
Sincerely,
Benjamin
coral 4A-70 project
hello out there in forum world,
no woodwork yet, maybe next weekend..... always hopeful.
in other developments, stephenred has lent me a well preserved leak stereo 30, germanium transistor, 12Wpc if you're lucky; will try with little boxed corals today, let you all know how it sounds... lovely little 6a3 amp with stephen.
also got mail from a hifi dealer in town (kr, coincident, zu, gallo and more), has just picked up 4a-70's, curious to see what can be done with 'em. should make it easier to make comparisons between cabs ...
thank you all, a
hello out there in forum world,
no woodwork yet, maybe next weekend..... always hopeful.
in other developments, stephenred has lent me a well preserved leak stereo 30, germanium transistor, 12Wpc if you're lucky; will try with little boxed corals today, let you all know how it sounds... lovely little 6a3 amp with stephen.
also got mail from a hifi dealer in town (kr, coincident, zu, gallo and more), has just picked up 4a-70's, curious to see what can be done with 'em. should make it easier to make comparisons between cabs ...
thank you all, a
coral 4A-70 project
hi,
leak and corals not a happy pairing.... leak out in one channel, will be trucked away to tech, (also has 'crunchy' volume pot).
leak runs out of juice, although nominally twice the power of the 6A3 amp; corals sound like underwhelming midrange drivers, treble ugly, cones not at all well controlled - a definite contrast to corals with SET amp: controlled cone, good 'bottom end', sweet airy treble, great mids
dont think the stereo 30's seen a serviceman in a generation, will report.
also, in response to the coral resembling fostex - i believe that fostex bought coral tooling and designs after the latter's demise,
later,
a
hi,
leak and corals not a happy pairing.... leak out in one channel, will be trucked away to tech, (also has 'crunchy' volume pot).
leak runs out of juice, although nominally twice the power of the 6A3 amp; corals sound like underwhelming midrange drivers, treble ugly, cones not at all well controlled - a definite contrast to corals with SET amp: controlled cone, good 'bottom end', sweet airy treble, great mids
dont think the stereo 30's seen a serviceman in a generation, will report.
also, in response to the coral resembling fostex - i believe that fostex bought coral tooling and designs after the latter's demise,
later,
a
Greets!
Add a rectangular 'top hat' to them to extend the mouth up closer to the ceiling. If you have the time, please experiment with smaller gaps to the ceiling than the original since you're the first to try it AFAIK. Of course a good seal to the BIB is imperative. In theory and according to HornResp it will restore any missing upper bass as well as lowering the system cut-off.
The only potential problem is that the extra length will shift the 3rd harmonic notch lower and in a worst case scenario it will be audible plus cause excessive driver excursion in which case it could severely reduce average SPL on material with significant bass.
Note too that different rooms usually = different acoustics, so if its width:depth ratio and/or basic shape and/or construction has changed significantly, then this will affect results and why I'm curious how close ceiling loading will fare. I've done it with woofer pipe corner horns with good results, but never 'full-range' drivers where comb filtering due to the extreme driver/mouth offset can turn mid-bass/lower mids clarity to mud.
GM
Add a rectangular 'top hat' to them to extend the mouth up closer to the ceiling. If you have the time, please experiment with smaller gaps to the ceiling than the original since you're the first to try it AFAIK. Of course a good seal to the BIB is imperative. In theory and according to HornResp it will restore any missing upper bass as well as lowering the system cut-off.
The only potential problem is that the extra length will shift the 3rd harmonic notch lower and in a worst case scenario it will be audible plus cause excessive driver excursion in which case it could severely reduce average SPL on material with significant bass.
Note too that different rooms usually = different acoustics, so if its width:depth ratio and/or basic shape and/or construction has changed significantly, then this will affect results and why I'm curious how close ceiling loading will fare. I've done it with woofer pipe corner horns with good results, but never 'full-range' drivers where comb filtering due to the extreme driver/mouth offset can turn mid-bass/lower mids clarity to mud.
GM
coral 4A-70 project ----- cabinets!
hello out there,
raw cabinets for little corals assembled, on to mounting drivers, stuffing and (hopefully) measuring results....
surprised at size - about 30% taller than i had imagined, one on top of the other gives some idea of the scale a double mouth horn might reach...
cab in 25mm ply, looks like best to mount drivers from rear of panel and use router to open up the front side, (fortunately a job to be done by skilled hands).
will take camera out to workshop next time and post a couple of progress pics,
happy trails,
adam
hello out there,
raw cabinets for little corals assembled, on to mounting drivers, stuffing and (hopefully) measuring results....
surprised at size - about 30% taller than i had imagined, one on top of the other gives some idea of the scale a double mouth horn might reach...
cab in 25mm ply, looks like best to mount drivers from rear of panel and use router to open up the front side, (fortunately a job to be done by skilled hands).
will take camera out to workshop next time and post a couple of progress pics,
happy trails,
adam
tame said:Hi,
2 years ago I've built BIB with FE168EZ - very good speakers for room with 2,5m ceiling. Now I moved them to another room with 3.2m ceiling - NO BASS. I played with stuffing, moved them close to corners, but the bass still far from results of 2,5m ceiling. Please HELP.
G'day Tame,
Have a look at this.
Will help with bass output and speed.
Cheers,
Alex
coral 4A-70 project - results from dayton tester
hi,
acquaintance has variety of full range drivers and a dayton woofer tester; presently experimenting with open baffle configurations.... has a technically inclined friend helping out - will encourage them to share their experiences on the forum.
hopefully text file and screenshot from dayton woofer tester attached below,
something to chew on,
thanks,
adam
hi,
acquaintance has variety of full range drivers and a dayton woofer tester; presently experimenting with open baffle configurations.... has a technically inclined friend helping out - will encourage them to share their experiences on the forum.
hopefully text file and screenshot from dayton woofer tester attached below,
something to chew on,
thanks,
adam
I just bought a pair of Terry Caine BIB's with Fostex 168 Sigmas
I am using a Tubelab Simple SE to power them.
They sound pretty good. This is my first horn and single driver full range speaker.
But they seem a little brittle or edgy.
I was told they had about 50hours on them. I've put another 50 on them since then. They have seemed to smooth out a tad. But still not what I expected from them.
Do they need more time? Or is this just how they sound.
Thanks
Nick
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I am using a Tubelab Simple SE to power them.
They sound pretty good. This is my first horn and single driver full range speaker.
But they seem a little brittle or edgy.
I was told they had about 50hours on them. I've put another 50 on them since then. They have seemed to smooth out a tad. But still not what I expected from them.
Do they need more time? Or is this just how they sound.
Thanks
Nick
Nice BIB's. The one looks at home in it's corner and close to the ceiling.
Sample stuffing treatments can be found at zillaspeak. The BIB is well documented and I think there's another Sigma builder here so might be some help.
I would at least venture a look inside to see what's there. If by edgy you mean towards the mid range I'd think it is all a front wave issue rather than back wave. However if damped too much inside, the mid and highs will be predominant.
My Fe127e BIB has stuffing in the peak, a piece of felt behind the driver and a "floor" of similar material to the peak at bottom. The BIB needs room to breathe.
Sample stuffing treatments can be found at zillaspeak. The BIB is well documented and I think there's another Sigma builder here so might be some help.
I would at least venture a look inside to see what's there. If by edgy you mean towards the mid range I'd think it is all a front wave issue rather than back wave. However if damped too much inside, the mid and highs will be predominant.
My Fe127e BIB has stuffing in the peak, a piece of felt behind the driver and a "floor" of similar material to the peak at bottom. The BIB needs room to breathe.
Hi Nick, your BIBs look great! When i saw the pic i had a few comments right away that you can consider to improve their sound.
1. Stuffing like lon mentioned above. They may be stuffed too much. I like to carefully lay my BIBs on their sides and reach in with a broomstick to pull out stuffing... careful not to hit any wires.
2. Position. To me they look like they can go deeper into the corners by a few inches. Get them as close as you can and see if the bass doesn't improve.
3. Your room looks thin. My BIBs are firing straight ahead without much if any toe in at all. I prefer them off axis to reduce/roll off the highs. I also have room treatment mounted on the wall next to the speaker. Why? Because if the high frequencies are not absorbed they will bounce off the wall and spoil things.
Try moving them deeper into the corners first and then try room treatment on the walls... if that doesn't work remove some stuffing.
They look great and should sound great too... let us know what you discover.
Godzilla
1. Stuffing like lon mentioned above. They may be stuffed too much. I like to carefully lay my BIBs on their sides and reach in with a broomstick to pull out stuffing... careful not to hit any wires.
2. Position. To me they look like they can go deeper into the corners by a few inches. Get them as close as you can and see if the bass doesn't improve.
3. Your room looks thin. My BIBs are firing straight ahead without much if any toe in at all. I prefer them off axis to reduce/roll off the highs. I also have room treatment mounted on the wall next to the speaker. Why? Because if the high frequencies are not absorbed they will bounce off the wall and spoil things.
Try moving them deeper into the corners first and then try room treatment on the walls... if that doesn't work remove some stuffing.
They look great and should sound great too... let us know what you discover.
Godzilla
No the ceilings are not suspended.
The bass is decent. Could be better.
They had a ton of stuffing in them when I got them. They also didn't produce any bass when I got them. As soon as I removed the stuffing I started getting decent bass.
There actually not in that room any more. There in a larger room now.
I found as soon as you start getting close to the corners they start sounding like crap. The bass gets sloppy and falls apart. They actually sound better a little further into the room and away from the side walls.
I'll and try and take pic of the current room tomorrow.
Nick
The bass is decent. Could be better.
They had a ton of stuffing in them when I got them. They also didn't produce any bass when I got them. As soon as I removed the stuffing I started getting decent bass.
There actually not in that room any more. There in a larger room now.
I found as soon as you start getting close to the corners they start sounding like crap. The bass gets sloppy and falls apart. They actually sound better a little further into the room and away from the side walls.
I'll and try and take pic of the current room tomorrow.
Nick
The Sigma's take many, many hours to burn in. I had mine in BIB and on open baffles. They are anything but brittle sounding, I found them to be on the warmer side. They will continue to burn in, but I wouldn't make any real judgements until you start to get up to 500+ hours. Some say it takes 1000 hours. Seriously. Give them the time, they'll repay you well. It takes a long time to loosen them up.
Best of luck.
Best of luck.
Getting Rid Of Brittleness
I have a pair of Fostex 208 sigma/T90A BIB's. They did not start "warming up" as soon as my Fostex 166 pipes did, but once they finally started breaking in, they started to sound tons better each time I played them, for a long time.
I cut a pair of pieces of masonite into a "banner" shape, and suspended them diagonally with the wider end at the top, into the second half of the horn (the back chamber). If you hang it so that it does not touch the inner sides of the cab, it seems to act as a resonator, and absorb some of the upper mid-range sound.
Finally, I ended up putting a 0.25mH coil in series with each 208. They cost $5.30 ea. from Madisound, and considered this last tweek to be indispensible. Madisound could help you calculate the value to try in the 168. I am not much for math, but I could look for the formula they gave me, and try to calculate it. I was told that the .25mH inductor would cause a vary gradual roll off, (flattening) starting at 500Hz.
Rooms vary, and peoples tastes vary. One person might like more bass, while another might like less, etc.
I never had a speaker where positioning would effect the sound so much. For example, at some point, one more inch closer to the wall can add a whole bunch of bass all of a sudden. Or, you can go in the opposite direction. If you find a place were the speaker position, listening position, toe in/toe out make magic, mark the floor with masking tape or something. You may find something that works better latter, but at least you can come back to it if other positions don't work as well.
These have been my experiences. I am happy with mine.
Sincerely,
Benjamin
I have a pair of Fostex 208 sigma/T90A BIB's. They did not start "warming up" as soon as my Fostex 166 pipes did, but once they finally started breaking in, they started to sound tons better each time I played them, for a long time.
I cut a pair of pieces of masonite into a "banner" shape, and suspended them diagonally with the wider end at the top, into the second half of the horn (the back chamber). If you hang it so that it does not touch the inner sides of the cab, it seems to act as a resonator, and absorb some of the upper mid-range sound.
Finally, I ended up putting a 0.25mH coil in series with each 208. They cost $5.30 ea. from Madisound, and considered this last tweek to be indispensible. Madisound could help you calculate the value to try in the 168. I am not much for math, but I could look for the formula they gave me, and try to calculate it. I was told that the .25mH inductor would cause a vary gradual roll off, (flattening) starting at 500Hz.
Rooms vary, and peoples tastes vary. One person might like more bass, while another might like less, etc.
I never had a speaker where positioning would effect the sound so much. For example, at some point, one more inch closer to the wall can add a whole bunch of bass all of a sudden. Or, you can go in the opposite direction. If you find a place were the speaker position, listening position, toe in/toe out make magic, mark the floor with masking tape or something. You may find something that works better latter, but at least you can come back to it if other positions don't work as well.
These have been my experiences. I am happy with mine.
Sincerely,
Benjamin
nikolas812 said:
I have to agree that tight positioning of the BIB in the corner though part of the concept was not satisfactory. I've tried this repeatedly and had the same impression.
About that break in of long hours, it can be speeded up if you are not averse to handling your new speakers. One idea is to run them in a sealed and damped box around the clock at full volume with pink noise or white noise. Pink is recommended as I recall. But for me I just tuned a radio to off frequency and let them blast inside a sealed box. Someone said an unused refrigerator works best. So out in a garage or someplace with an old radio at full volume stretched the surround. The noise will actually move the cone rapidly back and forth. This is a method of speeding up break in.
As a hobbyists these sorts of things get developed with familiarity with the components. Admittedly, I started doing these things myself with inexpensive speakers, so it's your call.