A Karlson builder is looking for an improvement over the Eminence Sigma which has ~130g mms. I had a pair of Eminence 18s made in the 1990's with 103g mms and qts=0.25. AA Craaft made an 18" IIRC with 77 grams mms. The game for his 18" K-coupler is to try to get the lowest moving mass together with a strong motor. Peavey offers 122g mms but their published spec of qes is near 0.5 (too high) plus it may be worse than that in reality. Without going to a custom build, is there anything which will beat the Sigma in regards to lower mass and good motor for this application?
EV DL18X has a QTS of .34, total moving mass .069 kg.
The EVM-18B Series II has a QTS of .36, probably similar total moving mass.
The original EV 18-B was probably lighter in the voice coil department.
The 18-B is a pretty "poppy" 18.
Freddi,
I remembered another unusually light 18" used in a TOA 480SC, a three way speaker with a 1" exit mid horn and a small tweeter. The cone seemed to be quite compliant, (soft)but I have no TS parameters or even the cone model number.
Looks like the acoustic crossover is around 800 Hz, pretty high for an 18.
The speaker sounds pretty good, if you could get the horn up to ear level, not so easy with a 100 lb all in one cab.
Did a fair amount of listening to it at a friend's house, and was surprised to find it was an 18", I had never seen a commercial 18" cross to a small 1" horn before.
Art
Attachments
It is an odd and disquieting thing that some speaker systems (like resonant BR) seem to "optimize" on drivers which don't seem right in other respects. Like having excessive mass to their cones or not the strongest motors possible.
I think the Karlson (and OB) do not have these aberrant inclination. Sure liked mine.... back in 1956.
Ben
I think the Karlson (and OB) do not have these aberrant inclination. Sure liked mine.... back in 1956.
Ben
Last edited:
I've got an empty 18" coupler which to try an EV - Art - do you know if MacKenzie's recone assemblies including the voicecoil are accurate reproductions?
An externally hosted image should be here but it was not working when we last tested it.
No experience with MacKenzie.
My only experience with non-OEM recones were JBLs using Waldom parts, not only were they 3dB less sensitive, they sounded like crap.
With the high cost of recones, I'd just look for a decent old EV18-B, there were tons made.
Check Minneapolis St.Paul Craigslist, just between me and my brother, we had 30 or 40.
Bill Batson, a reconer at Metro Sound & Lighting in St.Paul might know where to find one.
By the way, I have a pair of 8" Jensen Wizzer cones in Karlsons that you really should have, I'd trade for some raw woofers if you are interested.
Art
I don't know what a WT3 report is.
The only way I know to tell if a driver is "good" is to do an A/B test with a known good one, hard enough to do with new stuff, much harder with decades old drivers.
its difficult to get more than 1mm peak to peak at loud levels in my room with EV18B and it reaches a K-tube so transients sound "fast"
An externally hosted image should be here but it was not working when we last tested it.
Hi Freddi: Would you post the dimensions and "K" curve for the 18-inch Karlson you pictured? I'd like to construct one for my EV -18 reconned driver. I've not WT-3ed them yet. ....Michael
I don't have a drawing anymore but will get some dims - I think the wings are P=1/Q=1.7 up to a point then that's extended with a de-Q-ing slit- you could go with the Gauss 5181 K18 plans which has a bit more front and rear chamber. 18's will work in the regular Karlson K15
Cetec-Gauss 5181
http://img72.imageshack.us/img72/825/gaussbracing.jpg
here's a 5181 build - the guy was happy
http://gainclone.com/karlsonforum/index.php?topic=42.0
Cetec-Gauss 5181
http://img72.imageshack.us/img72/825/gaussbracing.jpg
here's a 5181 build - the guy was happy
http://gainclone.com/karlsonforum/index.php?topic=42.0
Last edited:
Hi Y'all,
Somewhere freddi talked about a 42" high Karlson slot for an 18". Going of that, and the picture from Post #6 I end up w/ the rough front view dimensions in the attached .pdf. If freddi can find the overall dimensions, and some of the internals, maybe we can make a drawing of his tall 18" Karlson.
Regards,
Somewhere freddi talked about a 42" high Karlson slot for an 18". Going of that, and the picture from Post #6 I end up w/ the rough front view dimensions in the attached .pdf. If freddi can find the overall dimensions, and some of the internals, maybe we can make a drawing of his tall 18" Karlson.
Regards,
hey tb46 - I'll try to dig it out of my mess - have not felt well after bp hit 240/110
here's some pix if not any useful dims - it probably would make a good 15" coupler - the main aperture came from a 2-variable calculator with "p=1", "q=1.7" then the aperture was extended to the top, narrowing to a point. My long distance friend who built it did a curved reflector at the top. The vent could be either center or both panels butted to form two side gap vents.
A High Aspect 18/15 coupler (Page 1) / Karlson / Fullrangedriver Forum
here's some pix if not any useful dims - it probably would make a good 15" coupler - the main aperture came from a 2-variable calculator with "p=1", "q=1.7" then the aperture was extended to the top, narrowing to a point. My long distance friend who built it did a curved reflector at the top. The vent could be either center or both panels butted to form two side gap vents.
A High Aspect 18/15 coupler (Page 1) / Karlson / Fullrangedriver Forum
Hi freddi,
Thanks for the additional link, especially the interior pictures. My main interest is in learning AkAbak as it applies to the Karlson aperture (xrk971 has pointed me in the right direction, but, owing to time restraints as well as being "conceptually challenged", I'm nowehere near yet).
Don't worry about this, get that HBP taking care of.
Regards,
Thanks for the additional link, especially the interior pictures. My main interest is in learning AkAbak as it applies to the Karlson aperture (xrk971 has pointed me in the right direction, but, owing to time restraints as well as being "conceptually challenged", I'm nowehere near yet).
Don't worry about this, get that HBP taking care of.
Regards,
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.