according to the late Wayne Green (Karlson Associates vice-president until ~1956), the 15 inch cabinet Karlson prototype was finished in the summer of 1951. A writeup titled “A New Approach In Loudspeaker Enclosures” appeared in the September 1952 issue of Audio Engineering Magazine and K15 appeared at the Hotel New Yorker Audio Fair of fall 1952. I have a full size blueprint of the first Karlson 12/”Karlsonette” dated 1954. K8 must have been ready for 1955. Karlson enclosures and their derivatives can be great. Use the slotted tube HF waveguide too.
I used this stacking arrangement in a set I built for a bass player. The speakers are K15 with JBL e140 drivers. With a little wattage, the results in studio were bone crushing and face peeling awesome. Have you tried them stacked mouth to mouth?
FWIW, the larger K15 cabinets sounded pretty bad on their sides. Not sure why precisely. Smaller Karlsons and Karlson derivatives might be better.
You may want to take a look at BBC slots, as well as the related Elliptoflex and RJ 'lemon' type cabinets.
You bet. Been listening for little over an hour and am very happy with the results. Even on the floor/carpet the bass is solid and well defined. The entire presentation is full and balanced. I have a few nits to pick, but those are only in comparison to multi-way speakers costing a lot more money. The Vifa FR again prove themselves as tiny giants and an amazing value.
Tomorrow I will do some room placement and height trials. As they are now, the room is completely filled with a wide stage. The most obvious shortcoming is what I perceive as some "cupping" in the mid-range. It sounds like something that can be adjusted by modifying the shape/curve of the wings. Don't think I would like anything absorbent on the inside of the wings, but I will experiment.
So I agree with X, very big, clean and dynamic sound far beyond what would be expected from $40 worth of drivers and ~$6 of foam board.
As mentioned by Freddi, going to a two way with the slotted tube HF waveguide could probably get to that last very feathery top end that the Vifas can't quite reach.
[/url][/IMG]
Tomorrow I will do some room placement and height trials. As they are now, the room is completely filled with a wide stage. The most obvious shortcoming is what I perceive as some "cupping" in the mid-range. It sounds like something that can be adjusted by modifying the shape/curve of the wings. Don't think I would like anything absorbent on the inside of the wings, but I will experiment.
So I agree with X, very big, clean and dynamic sound far beyond what would be expected from $40 worth of drivers and ~$6 of foam board.
As mentioned by Freddi, going to a two way with the slotted tube HF waveguide could probably get to that last very feathery top end that the Vifas can't quite reach.
Last edited:
I will have to try it sometime, I get the feeling the enhancement is more than 2x?
I just looked up the e140 - wow, Qts of 0.17! That is a powerful motor. 100dB. What's not to like? Must have really kicked some butt in a K15.
Last edited:
The LM3886 spec sheet says 100 W max. The MR series implementation is reported to output close to 68 W into 8 ohms. Even with the big Sunflower 8" design only attenuation is necessary. The only reason I started with them is I had the SF/MR system running for quick reference. It's not a good match as you need some pretty good multi-way speakers to even hear the quality of those amps.
Karlson pamphlet - from the X15 era (~1965)
btw - Acoustic Control's 115BK based on the Transylvania Power Co. product (which was based on X15) is a nice coupler and would be useful for midbass - or maybe some fullrange setups. I've been trying for some years to get info on the KHYBOE guts or Ernst Beck's BC-1 but to no avail yet.
page 1 http://imageshack.us/a/img14/5118/pg1u.jpg
page 2 http://imageshack.us/a/img541/7396/pg2o.jpg
page 3 http://imageshack.us/a/img716/9353/pg3cp.jpg
page 4 http://imageshack.us/a/img841/4263/pg4dj.jpg
page 5 http://imageshack.us/a/img22/6506/pg5q.jpg
page 6 http://imageshack.us/a/img577/2305/pg6k.jpg
page 7 http://imageshack.us/a/img26/8236/pg7hq.jpg
page 8 http://imageshack.us/a/img198/8089/pg8wr.jpg
Nice K15 ad
http://img208.imageshack.us/img208/332/axthekarlson.jpg
btw - Acoustic Control's 115BK based on the Transylvania Power Co. product (which was based on X15) is a nice coupler and would be useful for midbass - or maybe some fullrange setups. I've been trying for some years to get info on the KHYBOE guts or Ernst Beck's BC-1 but to no avail yet.
page 1 http://imageshack.us/a/img14/5118/pg1u.jpg
page 2 http://imageshack.us/a/img541/7396/pg2o.jpg
page 3 http://imageshack.us/a/img716/9353/pg3cp.jpg
page 4 http://imageshack.us/a/img841/4263/pg4dj.jpg
page 5 http://imageshack.us/a/img22/6506/pg5q.jpg
page 6 http://imageshack.us/a/img577/2305/pg6k.jpg
page 7 http://imageshack.us/a/img26/8236/pg7hq.jpg
page 8 http://imageshack.us/a/img198/8089/pg8wr.jpg
Nice K15 ad
http://img208.imageshack.us/img208/332/axthekarlson.jpg
Last edited:
Hi bcmbob,
Sounds like you build a winner.I wonder how this would sound like a little larger w/ an MTM driver set? I also like your amplifier (Post #293), do you have the layout documented somewhere?
Regards,
Out of curiosity I'm putting the TC9FD specs in an old program I have - Winspeakerz. I have never heard them in a traditional box but had planned to do so for comparison. Have some 1/2' MDF and X's Nautuless makes me wonder how they would sound non-horn loaded -sealed and/or BR. Hope that doesn't get me kicked out of the club.
The amp chassis is the result of a failed attempt to circulate the FEs to a few folks for audition. It's posted here.
IIRC, I think a plain sealed box at 5 liters might do the trick but you will only get about ~150 Hz bass. A bass reflex (gasp) will get to 55 Hz, as will a MLTL which has more controlled cone movement and tighter bass. You may get kicked out of the "We don't need no stinking bass rephlexes" club if you attempt on though.
The Nautiloss speaker is very easy to build and sounds great if you are looking for a clean mid/high speaker as the top end to a FAST.
The Nautiloss speaker is very easy to build and sounds great if you are looking for a clean mid/high speaker as the top end to a FAST.
OUCH !! 
That leaves me with only one option - sealed- cause TL is still a form of horn loading from my understanding. There is nothing to compare with the economy and flexibility of foam core projects, but I still want to hear the "unmentionable". I'll post my results over on the Parts Express Speaker Forum - there are some folks over there who still have open minds.
That leaves me with only one option - sealed- cause TL is still a form of horn loading from my understanding. There is nothing to compare with the economy and flexibility of foam core projects, but I still want to hear the "unmentionable". I'll post my results over on the Parts Express Speaker Forum - there are some folks over there who still have open minds.
Last edited:
A TL is simply a length of duct/pipe that supports a resonant mode (a wave) and enhances certain frequencies. If it is open ended, it supports a quarter-wave mode so the line can be much shorter for a corresponding deeper bass frequency. A closed ended one supports half-wave as the lowest mode so it is twice as long for the same frequency. Naturally, sealed ones do not have any sound output other than through the driver cone so they are less efficient as open ended ones which basically channel some of the back output outside. There are also other differences like odd/even harmonics that one or the other doesn't support - so they inherently sound different. But if the sealed TL does its job by absorbing all the different harmonics and reflections, then you should not hear this coloration.
That's very interesting. When I saw your new design and comments yesterday the first thing that came to mind was getting a few more FC panels and making a long straight shaft at that 3' length just to hear only the front of the Vifa. Would that be useful? - just suck up all the energy from the back. I wasn't considering any practical application - just a test rig for a couple $.
Last edited: