Mr. Cain-
I have long wished I could hear a pair of Abbys. Is there anyone who carries them in Baltimore or Washington?
I did not see any dealers listed on the website. I'd be happy to even know of anyone here who bought them in the BaltoWash area and would let me hear them in exchange for their 6-pack of choice...
GnD
I have long wished I could hear a pair of Abbys. Is there anyone who carries them in Baltimore or Washington?
I did not see any dealers listed on the website. I'd be happy to even know of anyone here who bought them in the BaltoWash area and would let me hear them in exchange for their 6-pack of choice...
GnD
Buschhorn
Coredump:
Damping the CC on the MKII design was a little bit of trial and error, and in my case was done totally by ear. Futhermore the break-in period of Fostex is legendary, so it's a long time 'til you're sure you're listening to the right thing.
Anyway, I'll have to pull the driver to quantify it.
Coredump:
Damping the CC on the MKII design was a little bit of trial and error, and in my case was done totally by ear. Futhermore the break-in period of Fostex is legendary, so it's a long time 'til you're sure you're listening to the right thing.
Anyway, I'll have to pull the driver to quantify it.
Re: Buschhorn
Chris,
so I noticed. ;-)
I made a "felt belt" around the driver (just glued some felt to the inside of the cabinet), as the drivers suffered from some bad reflections. As a result, I had to remove some wool as it started to sound over-damped. Tricky business.
Don't bother, I'll keep fiddling. Thanks anyway.
Best regards,
Oliver
Chris,
so I noticed. ;-)
I made a "felt belt" around the driver (just glued some felt to the inside of the cabinet), as the drivers suffered from some bad reflections. As a result, I had to remove some wool as it started to sound over-damped. Tricky business.
Don't bother, I'll keep fiddling. Thanks anyway.
Best regards,
Oliver
Re: Re: Buschhorn
My felt was recycled from old speaker boxes (courtesy of Dave/Planet10) and was approx 1/2" thick. I recall lining the side walls of the CC, and either 2 or 3 rather irregularly stuffed layers along the back wall.
FWIW, I'd consider the configuration of the CC on this particular enclosure in need of serious design. No doubt other DIY'ers have concluded the same, and perhaps could post their findings ( on another thread)
coredump said:Chris,
so I noticed. ;-)
I made a "felt belt" around the driver (just glued some felt to the inside of the cabinet), as the drivers suffered from some bad reflections. As a result, I had to remove some wool as it started to sound over-damped. Tricky business.
Don't bother, I'll keep fiddling. Thanks anyway.
Best regards,
Oliver
My felt was recycled from old speaker boxes (courtesy of Dave/Planet10) and was approx 1/2" thick. I recall lining the side walls of the CC, and either 2 or 3 rather irregularly stuffed layers along the back wall.
FWIW, I'd consider the configuration of the CC on this particular enclosure in need of serious design. No doubt other DIY'ers have concluded the same, and perhaps could post their findings ( on another thread)
I also built a pair of clones a while back and will give a little info as I know it. I am almost certain that Terry uses Alder for his cabinets or the baffles anyway. Alder is a very very soft (hard)wood and could probably be replaced with American Cherry if you have trouble sourcing it. I was told the upper portion of the cabinet, above the driver, is filled. The lower portion is unfilled. I lined mine with asphalt. I did not use a circular baffle as Terry did but did make a rectangular baffle with rounded edges.
And now the props to Terry. I am absolutely in love with these little TQWT's. They are used in my all tube system and excel at music based on female vocals, jazz, stringed instruments.... If I was not a DIY guy or professional woodworker I would have purchased these from Terry and they would be worth every cent spent.
c.
And now the props to Terry. I am absolutely in love with these little TQWT's. They are used in my all tube system and excel at music based on female vocals, jazz, stringed instruments.... If I was not a DIY guy or professional woodworker I would have purchased these from Terry and they would be worth every cent spent.
c.
Rick Shultz built a TL with a non-linear taper with good results...
http://www.t-linespeakers.org/projects/exolinear/curve.html
Another fellow developed a TL with a reverse exponential taper -- he was going to try to get a patent, but finally just put it into the DIY community.
dave
http://www.t-linespeakers.org/projects/exolinear/curve.html
An externally hosted image should be here but it was not working when we last tested it.
Another fellow developed a TL with a reverse exponential taper -- he was going to try to get a patent, but finally just put it into the DIY community.
dave
Re: Re: TQWP with Circular Section ?
The taper (increase in diameter with length) would be linear, but the cross-sectional area A=(pi)*r^2 would be quadratic with length. (Seems weird to me too, but the math don't lie.)
Should be able to sim it in MJK's sections worksheet, approximating a quadratic profile by using many different linear sections?
cheesehead
planet10 said:
The taper (increase in diameter with length) would be linear, but the cross-sectional area A=(pi)*r^2 would be quadratic with length. (Seems weird to me too, but the math don't lie.)
Should be able to sim it in MJK's sections worksheet, approximating a quadratic profile by using many different linear sections?
cheesehead
Greets!
AFAIK the worksheets (WS) are only using the cross sectional areas (CSA) at each end and the length to define a conical expansion of whatever its 'M' factor (taper ratio) turns out to be, so doesn't matter what CSA shape you input, ergo if you build a very high aspect ratio cab WRT width/depth, the sim won't be as accurate above the cab's compression BW.
Of course if you want to define a specific 'M' factor with 'x' BW, such as exponential (M = 1), then SL and length become the variables and the 'sections' WS will need to be used.
GM
AFAIK the worksheets (WS) are only using the cross sectional areas (CSA) at each end and the length to define a conical expansion of whatever its 'M' factor (taper ratio) turns out to be, so doesn't matter what CSA shape you input, ergo if you build a very high aspect ratio cab WRT width/depth, the sim won't be as accurate above the cab's compression BW.
Of course if you want to define a specific 'M' factor with 'x' BW, such as exponential (M = 1), then SL and length become the variables and the 'sections' WS will need to be used.
GM
Re: Re: Re: TQWP with Circular Section ?
I think you're mistaken about a rectangular cross-section being different than a circular cross-section.
circular:
A = pi*r^2 -- quadratic.
rectangular:
A = x * y -- linear?
Since the ratio of x:y stays constant because of the linear taper,
x = k*y where k = x/y
so:
A = (k*y)*y = k*y^2 -- quadratic as well.
Since MJKs worksheets just consider CSA w/rt to taper, it doesn't know whether you're using a circular or rectangular shape. However, the taper ratio is different.
--
Danny
cheesehead said:
I think you're mistaken about a rectangular cross-section being different than a circular cross-section.
circular:
A = pi*r^2 -- quadratic.
rectangular:
A = x * y -- linear?
Since the ratio of x:y stays constant because of the linear taper,
x = k*y where k = x/y
so:
A = (k*y)*y = k*y^2 -- quadratic as well.
Since MJKs worksheets just consider CSA w/rt to taper, it doesn't know whether you're using a circular or rectangular shape. However, the taper ratio is different.
--
Danny
I think we're saying the same thing, just not reading the same thing...
In most cases, when you're changing the cross-sectional area of a speaker, only one dimension is changing. Say, rectangular baffle and triagonal side. Let h be the distance from the top of the "pipe", with a cross-sectional area (CSA) of zero at the top, then
x = constant (the baffle is the same width throughout)
y = c * h (the width of the side is linear with the distance from the top)
CSA = x * y = c * x * h linear with distance from the top
For a cylindrical pipe where the radius is linear with the distance from the top,
r = c * h
Then,
CSA = pi * (c * h)^2 = pi * c^2 *h^2 quadratic with distance from the top
You could get the same thing by building a square pyramid...
In any case, I think you could use MJK's sections program, and enter a number of sections with linear increase in CSA but increasing "taper" to approximate a quadratic increase in CSA.
In most cases, when you're changing the cross-sectional area of a speaker, only one dimension is changing. Say, rectangular baffle and triagonal side. Let h be the distance from the top of the "pipe", with a cross-sectional area (CSA) of zero at the top, then
x = constant (the baffle is the same width throughout)
y = c * h (the width of the side is linear with the distance from the top)
CSA = x * y = c * x * h linear with distance from the top
For a cylindrical pipe where the radius is linear with the distance from the top,
r = c * h
Then,
CSA = pi * (c * h)^2 = pi * c^2 *h^2 quadratic with distance from the top
You could get the same thing by building a square pyramid...
In any case, I think you could use MJK's sections program, and enter a number of sections with linear increase in CSA but increasing "taper" to approximate a quadratic increase in CSA.
This is from page 18 of MJK's TL Alignment Tables.
I read this to mean that a cross-sectional area at any point X along the line length is predictable by equation. Any deviation from the original rate of change would make this impossible. Never mind that in practice, a stepped transition doesn't make much difference.)
ensen.
Hello,
I finally finished my Clabby. See the attached picture. They sound great! I may have a chance to compare them with the real Abby at the Hi-Fi Montreal Festival in april. Usually there is a room with the Abby and I always spend a lot of time in it.
I decided to ignore a bit all the calculation I did with MJK sheets and also take into accound the dimensions of the real Abby. It is a compromise between both design.
Just for fun, I tried to use a BSC and it completely destroyed the mid-range. Basically I was using a very similar version of the BSC used by MJK for his FE164 project.
I am now using them with a pair of ASL wave-8. Honessly I prefer this match over my Pass Zen V4. I will probably build the first version of the Zen (apprently better for full-range speaker?) or maybe the Zen Lite is better?
Anyway, I will have to do some experiementation.
Nothing special in these speakers: FE167E, silver-plated copper wire with teflon insulation, high quality binding post (but not the cardas), 5/8'' MDF, African Mahogany veneer finished with danish oil.
BTW, please start a different subject if this is not to discuss about the Abby, thx.
I finally finished my Clabby. See the attached picture. They sound great! I may have a chance to compare them with the real Abby at the Hi-Fi Montreal Festival in april. Usually there is a room with the Abby and I always spend a lot of time in it.
I decided to ignore a bit all the calculation I did with MJK sheets and also take into accound the dimensions of the real Abby. It is a compromise between both design.
Just for fun, I tried to use a BSC and it completely destroyed the mid-range. Basically I was using a very similar version of the BSC used by MJK for his FE164 project.
I am now using them with a pair of ASL wave-8. Honessly I prefer this match over my Pass Zen V4. I will probably build the first version of the Zen (apprently better for full-range speaker?) or maybe the Zen Lite is better?
Anyway, I will have to do some experiementation.
Nothing special in these speakers: FE167E, silver-plated copper wire with teflon insulation, high quality binding post (but not the cardas), 5/8'' MDF, African Mahogany veneer finished with danish oil.
BTW, please start a different subject if this is not to discuss about the Abby, thx.
Attachments
"Clabby"....
They look good Francois.
I too am looking at building something like this. My nephew has the TL/Voight bug. His Dad gave him 2 pairs of DCM TF 250's and he loves em and wanted to "hotrod" them. I suggested that a completely new speaker might be just as easy (He still wants to mod them in addition to building some others).
I have always like TLs and have heard a few. When I stumbled across the Voight pipes on the Internet I was intriqued.
Email me if you would allow a couple in depth questions.
nanook
They look good Francois.
I too am looking at building something like this. My nephew has the TL/Voight bug. His Dad gave him 2 pairs of DCM TF 250's and he loves em and wanted to "hotrod" them. I suggested that a completely new speaker might be just as easy (He still wants to mod them in addition to building some others).
I have always like TLs and have heard a few. When I stumbled across the Voight pipes on the Internet I was intriqued.
Email me if you would allow a couple in depth questions.
nanook
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