Sexy Brazilian device!
Freddi ,
You are totally right about that , the sharper slope and lower crossover point would make the compression driver sound much louder ..... I used to have these Selenium D220ti drivers on a third order passive crossover at 2khz and it was raucous and ear-raping LOUD! Eek!
It required "padding" because it was outrunning my big 4-way horn system by 6db! (and that system uses good sized EV mid-horns that are 2 feet deep loaded with highly efficient 10" EV drivers) ...
The Selenium is remarkably loud and a smooth performer for being a small compression driver that you can buy for $50 , it truly is a great deal ...
The 1st order passive crossover with a very high crossover point was intentional to knock down the Selenium's lower range in an effort to get it to integrate with this Karlflex .... I could also go with the 12db per octave slope as you suggested or even the 18db slope at 2khz but it would require quite a bit of attenuation set up that way ................. As it is arranged right now it is still a few decibels too hot with this Selenium.
Listening to it and other compression drivers that i set up this way i have to say that i like the sound of the gently rising response and the shallow filter curves, they just sound very natural to me, my ears also really appreciate the lack of shout and squawk (the harsh weirdness often heard in a compression driver's lower range is gone) and you cannot beat the simplicity of this, not to mention great transient response....................
The impedance curve of the system will be higher between 700hz and 10k (measured at about 10ohms to 16ohms through that frequency range with the transformer driven Frankenpiezo which uses the same 2uf poly cap and an 8ohm transformer tap for a load) but i don't mind.....
I am sure i could get fancy and use more components to flatten the impedance response while maintaining a similar frequency/amplitude curve but that will be something for me to revisit in the future if i decide that I want to get really serious about crossover networks ... ...
Freddi ,
You are totally right about that , the sharper slope and lower crossover point would make the compression driver sound much louder ..... I used to have these Selenium D220ti drivers on a third order passive crossover at 2khz and it was raucous and ear-raping LOUD! Eek!
It required "padding" because it was outrunning my big 4-way horn system by 6db! (and that system uses good sized EV mid-horns that are 2 feet deep loaded with highly efficient 10" EV drivers) ...The Selenium is remarkably loud and a smooth performer for being a small compression driver that you can buy for $50 , it truly is a great deal ...
The 1st order passive crossover with a very high crossover point was intentional to knock down the Selenium's lower range in an effort to get it to integrate with this Karlflex .... I could also go with the 12db per octave slope as you suggested or even the 18db slope at 2khz but it would require quite a bit of attenuation set up that way ................. As it is arranged right now it is still a few decibels too hot with this Selenium.
Listening to it and other compression drivers that i set up this way i have to say that i like the sound of the gently rising response and the shallow filter curves, they just sound very natural to me, my ears also really appreciate the lack of shout and squawk (the harsh weirdness often heard in a compression driver's lower range is gone) and you cannot beat the simplicity of this, not to mention great transient response....................
The impedance curve of the system will be higher between 700hz and 10k (measured at about 10ohms to 16ohms through that frequency range with the transformer driven Frankenpiezo which uses the same 2uf poly cap and an 8ohm transformer tap for a load) but i don't mind.....
I am sure i could get fancy and use more components to flatten the impedance response while maintaining a similar frequency/amplitude curve but that will be something for me to revisit in the future if i decide that I want to get really serious about crossover networks ... ...
Last edited:
I've got a 12pe32 in a K12 and that's hot enough so running a K-tube with compression driver is ok - maybe a bit bright. I once ran the little tube on top of a JBL 4638 cabinet which has two 15" woofers in parallel and that combo wasn't lacking much if at all. Have you found an elevation which you prefer with your Karlflex? Sometime I should use the 2035 woofers out of those 4638 for K. Subjectively, a 5.3" long K-tube seems to have nice dispersion even up close and off axis - the vertical window seems good as I've put one up on a 48" tall K-slotted 18" woofer cabinet. I'm pretty sure the upper octave beamwidth narrows and its not strictly CD - they're a nice way to do treble if the crossover can be kept high enough.
"this" plus a pair of good tapped horn subwoofer should be fun for a home system
"this" plus a pair of good tapped horn subwoofer should be fun for a home system
Last edited:
SOUND LASERS !!!! pew pew pew!! (sci-fi laser noises)
HAHAHA I LOVE IT !!
The awesome marketing of the 50s and 60s ... Wonderful stuff !!
The selling points listed in this ad are kind of interesting too, a few of them give me something to think about ..
I haven't experimented with the Karflex at different heights yet , but i did experiment with different angles on the Selenium's slotted K-tube ...... 45 degrees seemed to be too high of an angle, so i ended up tilting it to around 30 degrees and that worked well, dispersion around the room is good enough at this angle and the sound quality is excellent
Your four 15s in stacked K-cabs would be a fun setup for sure! Any idea what the T/S parameters are on those 2035 drivers? .
Freddi , The array seen in your following post , are those Metro T-15s?
P.S.
I am taking some pictures of this K-tube and my other horns & lenses that i have used with the Selenium today , i will post them this evening or tomorrow ..
I've got a 12pe32 in a K12 and that's hot enough so running a K-tube with compression driver is ok - maybe a bit bright. I once ran the little tube on top of a JBL 4638 cabinet which has two 15" woofers in parallel and that combo wasn't lacking much if at all. Have you found an elevation which you prefer with your Karlflex? Sometime I should use the 2035 woofers out of those 4638 for K. Subjectively, a 5.3" long K-tube seems to have nice dispersion even up close and off axis - the vertical window seems good as I've put one up on a 48" tall K-slotted 18" woofer cabinet. I'm pretty sure the upper octave beamwidth narrows and its not strictly CD - they're a nice way to do treble if the crossover can be kept high enough.
"this" plus a pair of good tapped horn subwoofer should be fun for a home system
HAHAHA I LOVE IT !!
The awesome marketing of the 50s and 60s ... Wonderful stuff !!
The selling points listed in this ad are kind of interesting too, a few of them give me something to think about ..
I haven't experimented with the Karflex at different heights yet , but i did experiment with different angles on the Selenium's slotted K-tube ...... 45 degrees seemed to be too high of an angle, so i ended up tilting it to around 30 degrees and that worked well, dispersion around the room is good enough at this angle and the sound quality is excellent
Your four 15s in stacked K-cabs would be a fun setup for sure! Any idea what the T/S parameters are on those 2035 drivers? .
Freddi , The array seen in your following post , are those Metro T-15s?
P.S.
I am taking some pictures of this K-tube and my other horns & lenses that i have used with the Selenium today , i will post them this evening or tomorrow ..
Last edited:
that's the early 1980's I think - Mrs. Karlson apparently handed out licenses like stock was handed out in "The Producers"
here's a pretty tube and driver - so I know some try the technique - assume this is a field coil compression driver (?)
AUDIOPHILE FIELD-COIL SPEAKERS | Wolf von Langa
in the range where they are suitable - I would agree with his statement
"Now I’m almost convinced: Horns were yesterday…"
http://www.kilimanjaro-series.com/news/a2000-karlson-tube.html
that tube is somewhat longer than the one made by Transylvania Power Company - "THE TUBE" was about 5.3" long
and had a 2 degree downwards sidewall taper - some think that's for better pull off the mold - Walter Alan Zintz said
it was done in accordance with the theory in Karlson's 1951 "Acoustic Transducers" patent
here's a pretty tube and driver - so I know some try the technique - assume this is a field coil compression driver (?)
AUDIOPHILE FIELD-COIL SPEAKERS | Wolf von Langa
in the range where they are suitable - I would agree with his statement
"Now I’m almost convinced: Horns were yesterday…"
http://www.kilimanjaro-series.com/news/a2000-karlson-tube.html
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
that tube is somewhat longer than the one made by Transylvania Power Company - "THE TUBE" was about 5.3" long
and had a 2 degree downwards sidewall taper - some think that's for better pull off the mold - Walter Alan Zintz said
it was done in accordance with the theory in Karlson's 1951 "Acoustic Transducers" patent
Last edited:
re:2035H - its not as heavy duty as a 2226 but think its a very good woofer for hifi - (had one in a near-copy of Karlson's X15)
I'll plug it into TB46's K's hornresp model soon
2035H fs - 48, qts - 0.34, qms - 5, qes - 0.36, vas - 140.5, Pe - 400, Le 0.25 mH, Sd - 0.088, BL - 16.6, mms - 85g
does your Selenium compression driver have ferrofluid? - a reasonably flat input Z is good for running with just a capacitor highpass -
a swamping resistor across the driver can help with regular drivers
I'll plug it into TB46's K's hornresp model soon
2035H fs - 48, qts - 0.34, qms - 5, qes - 0.36, vas - 140.5, Pe - 400, Le 0.25 mH, Sd - 0.088, BL - 16.6, mms - 85g
does your Selenium compression driver have ferrofluid? - a reasonably flat input Z is good for running with just a capacitor highpass -
a swamping resistor across the driver can help with regular drivers
Last edited:
tb46's cabinet from post 1188 with JBL's 2035H 2pi, 39v - which will just about hit xmax - if Le is crazy low at 0.25mH, then lays not much above Re over a lot of the range
how close do rooms with flimsy modern 2x4 sheetrock walls and thin particleboard floors come close to 1pi conditions ?
how close do rooms with flimsy modern 2x4 sheetrock walls and thin particleboard floors come close to 1pi conditions ?
Post #1745
Hi freddi,
You find the wildest things.
Going by the description on the website, the horn driver has a 2" opening, and that makes the k-tube about 2"O.D. x 14" long.
I tried to scale it in Picture Publisher using a driver opening of about 13.5" as a starting point. There are rulers horizontally and vertically in the screen print, and guide dots on 1" centers. Also, looking closely at the base of the tube, this may be a rolled product?
Regards,
Hi freddi,
You find the wildest things.
Going by the description on the website, the horn driver has a 2" opening, and that makes the k-tube about 2"O.D. x 14" long.
I tried to scale it in Picture Publisher using a driver opening of about 13.5" as a starting point. There are rulers horizontally and vertically in the screen print, and guide dots on 1" centers. Also, looking closely at the base of the tube, this may be a rolled product?
Regards,
Attachments
Last edited:
it may well be rolled - interesting machining ability to vary the slots so precisely - - Transylvania Power Company allegedly made a 2" format tube and probably around 11" length - I made that size with 2" pvc but didn't have a 2" driver to properly energize the thing. Seems like it would have narrow dispersion at high frequencies when viewed straight down the tube - there is energy propagated at right angles to the tube's long axis.
imo - K-tube used properly have a very nice sound
imo - K-tube used properly have a very nice sound
Does this make us tube snobs now?
Freddi ,
Those audiophile slotted K-tubes from your post #1745 are gorgeous!
I really like the way they are angled downward and long enough to reach down to the level of the driver below it improving coherence, seems like smart design ...
That JBL 2035 looks really good ! More motor strength than an Eminence Kappalite 3015LF-4 , and lower voicecoil inductance per ohm as well !! It is not as strong as your 15" B&C models but still very useful
I don't believe it uses ferrofluid .... I was considering a swamping resistor across the driver , at least to electrically damp the Selenium near it's resonance to help protect it ..
Freddi ,
Those audiophile slotted K-tubes from your post #1745 are gorgeous!
I really like the way they are angled downward and long enough to reach down to the level of the driver below it improving coherence, seems like smart design ...
That JBL 2035 looks really good ! More motor strength than an Eminence Kappalite 3015LF-4 , and lower voicecoil inductance per ohm as well !! It is not as strong as your 15" B&C models but still very useful
I don't believe it uses ferrofluid .... I was considering a swamping resistor across the driver , at least to electrically damp the Selenium near it's resonance to help protect it
..
Pictures as promised
I love this driver , but it looks like their decal printer was having a bad day when they made this one (i bought these back in 2010)
and here are a few different horns and a Dayton waveguide or lens along with the cardboard slotted k-tube (which i really like because it sounds great!) .... I tried my best to match the contour of the Transylvania Power Company tubes , but i know it is not quite exactly right , i may try again ...
This tube's cardboard is actually thicker than it looks in the picture, but to stiffen it further i can brush on a glue that will soak into the paper then i would paint them as well ... This was just a fun experiment though and if i really wanted something more permanent i would buy some strong plastic pipe with 1" inner diameter.
I love this driver , but it looks like their decal printer was having a bad day when they made this one
(i bought these back in 2010)
An externally hosted image should be here but it was not working when we last tested it.
and here are a few different horns and a Dayton waveguide or lens along with the cardboard slotted k-tube (which i really like because it sounds great!) .... I tried my best to match the contour of the Transylvania Power Company tubes , but i know it is not quite exactly right , i may try again ...
An externally hosted image should be here but it was not working when we last tested it.
This tube's cardboard is actually thicker than it looks in the picture, but to stiffen it further i can brush on a glue that will soak into the paper then i would paint them as well ... This was just a fun experiment though and if i really wanted something more permanent i would buy some strong plastic pipe with 1" inner diameter.
Last edited:
great looking K-tube - how did you generate the curve and cut it so precisely? when I made some out of 1" pvc, I kept mucking wih elliipses on a printer to get one which left a 1/8" starting gap and ~5.5" half ellipse length -what glues would make it more rigid/better damped? - I've got a big pair of white EV horns never used - think they want 1.4" driver and are 60x40 - Selenium has made some real good drivers - their slot loaded tweeters were great for the money
Last edited:
Freddi ,
I had a very long piece of this tubing so i cut a few pieces off and went about it trial & error style... I did end up wasting a few 6" lengths before getting the shape of the cut right ... I was just eyeballing it , nothing fancy ...
For glue i was just thinking about thinning out some wood glue and brushing that on a few times til it soaks in ... It would be an experiment ...
I have never tried the Selenium slot loaded tweeters but these compression drivers sure are great ...
I did make some simple 42" tall TL tower cabs loaded with Selenium 8W4P drivers a while back for a friend (after trying those same drivers in a few other cabs yielding unsatisfactory results) i was highly impressed with how well they worked in the TL (QWP) cabinets!
Tilted
TB46 ,
I have not directly A/B tested them against each other ....
My impressions are that they both do sound very good crossed over in this same manner ...
The HR60 is about 100 times larger!
(i am not even really exaggerating if you take into account the depth of the EV horn) so the Transylvanian K-tube definitely wins in the compact/portability department but the tube won't have the gain and consistent dispersion that this big CD horn has ...
In regards to dispersion in listening tests i have noticed that the tube is a little hotter directly on-axis (as in looking down the tube) but once i got the angle right that issue became much less apparent for some reason, and i could then walk around the room enjoying enough consistency in the high end to be very happy with it.... This is a great affordable and easy-to-make combination if you are trying to integrate with a midrange driver that has legit 1w/1m spl ratings in the high 90s (in the upper midrange) and especially if you prefer the sound of a rising response....
The same driver & cap on the EV HR60 has a response that is not nearly as rising or hyped due to the response tilt of the CD horn design, it ends up being closer to flat, and that was precisely the reason why i decided to try the 2uf series poly cap on the D220ti in the first place.... It turned out that the 6db per octave slope almost perfectly compensated for the CD tilt !
TB46 ,
I have not directly A/B tested them against each other ....
My impressions are that they both do sound very good crossed over in this same manner ...
The HR60 is about 100 times larger!
(i am not even really exaggerating if you take into account the depth of the EV horn) so the Transylvanian K-tube definitely wins in the compact/portability department but the tube won't have the gain and consistent dispersion that this big CD horn has ... In regards to dispersion in listening tests i have noticed that the tube is a little hotter directly on-axis (as in looking down the tube) but once i got the angle right that issue became much less apparent for some reason, and i could then walk around the room enjoying enough consistency in the high end to be very happy with it.... This is a great affordable and easy-to-make combination if you are trying to integrate with a midrange driver that has legit 1w/1m spl ratings in the high 90s (in the upper midrange) and especially if you prefer the sound of a rising response....
The same driver & cap on the EV HR60 has a response that is not nearly as rising or hyped due to the response tilt of the CD horn design, it ends up being closer to flat, and that was precisely the reason why i decided to try the 2uf series poly cap on the D220ti in the first place.... It turned out that the 6db per octave slope almost perfectly compensated for the CD tilt !
Last edited:
EV HR60 v. K-tube
Hi MMJ,
Post #1756: "...the tube won't have the gain and consistent dispersion that this big CD horn has ...is a great affordable and easy-to-make combination..."
Thanks for the additional information.
I have a few Altec 511B horns on the shelf, and some of the old Altec 806a (?) drivers as well as the Selenium D220Ti (and some old JBL horn,I think. Too much stuff...). I don't have the time to set something up to make meaningfull comparisons, so I asked. I've always been partial towards the sound of these types of horns. I guess, today the waveguide is the thing to do for the home.
I see your reasoning for a simple crossover for a quick test; I like 3rd order crossovers for horns in general, also here is a quick reference to CD horn/waveguide EQ (you are probably aware of this, there is also a lot of stuff on audioheritage.com):
http://www.diyaudio.com/forums/mult...170m0-waveguide-experiment-4.html#post1378211
I have some fiberglass tube that are ~ 1.020"O.D. w/ a .030"nom. wall. Rough measurements confirm that the I.D. is about .960" to .963". I think that should be close enough for government work. Maybe I'll get around to butchering one of those.
Regards,
Hi MMJ,
Post #1756: "...the tube won't have the gain and consistent dispersion that this big CD horn has ...is a great affordable and easy-to-make combination..."
Thanks for the additional information.
I have a few Altec 511B horns on the shelf, and some of the old Altec 806a (?) drivers as well as the Selenium D220Ti (and some old JBL horn,I think. Too much stuff...). I don't have the time to set something up to make meaningfull comparisons, so I asked.
I've always been partial towards the sound of these types of horns. I guess, today the waveguide is the thing to do for the home.I see your reasoning for a simple crossover for a quick test; I like 3rd order crossovers for horns in general, also here is a quick reference to CD horn/waveguide EQ (you are probably aware of this, there is also a lot of stuff on audioheritage.com):
http://www.diyaudio.com/forums/mult...170m0-waveguide-experiment-4.html#post1378211
I have some fiberglass tube that are ~ 1.020"O.D. w/ a .030"nom. wall. Rough measurements confirm that the I.D. is about .960" to .963". I think that should be close enough for government work. Maybe I'll get around to butchering one of those.
Regards,
Hi there, update from Denmark. The Karlflex with multiple Freddi Stubs is taking form. But with everyday life intervening all the time, things progress in a somewhat slow pace And with this special design we are dealing with a quite different animal, so I'm very curious about this box and it's merits.
I have measured T/S for the 15LB100 and Le was 0,55 mH at 10k hz. When I simmed in Akabak the FR was up by 2db from 200 hz, comparred with the given specs, so yes I think it has sufficient output in the 1000-2000 hz. But in a near futuretime I'll have a more valid answer
View attachment The Box 15LB100.pdf
And with this special design we are dealing with a quite different animal, so I'm very curious about this box and it's merits. I have measured T/S for the 15LB100 and Le was 0,55 mH at 10k hz. When I simmed in Akabak the FR was up by 2db from 200 hz, comparred with the given specs, so yes I think it has sufficient output in the 1000-2000 hz. But in a near futuretime I'll have a more valid answer
View attachment The Box 15LB100.pdf
I've had to fill a tip w. epoxy - is the tube on the left 1"ID? how did you manage the taper on the other tube? - it must be close to Transylvania's "TheTube" which is ~5.3" long, 1"ID at the inlet and ~2 degree downwards taper sidewalls - the slot expansion might be a bit tight but don't really know
here's "The Tube" next to a schedule 40 1" pvc tube I made
Altec 511 cow bells make good old-school midrange horn for Klipsch-type setups
here's "The Tube" next to a schedule 40 1" pvc tube I made
Altec 511 cow bells make good old-school midrange horn for Klipsch-type setups
Last edited: