8" Hall of Fame

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interesting, the problem I have with whizzers is they really cloud up the mid range.
I can clean that up but putting a grain or two behind the whizzer which works great unless you get crazy with the volume and shake it out.

Since the classic doesn't have a whizzer I'll probably go with those.
That said I did just picked up a pair of Pioneer 8" with a whizzer so I'm anxious to see how they sound.
 
Thanks for the charts Freddi. I love the Pioneer driver. My 15 year old son enjoys them every day. Don't you also have charts for the TB 1808 and the Beta 12lta too? I wonder if we can compare them all together?

As for the 12lta vs the TB 1808, I hooked up the 12lta and sat it on top of the same subwoofer and in the same spot as the 1808 to compare them. The 12lta is more efficient by far. I had to turn up the sub (both gain and frequency) to blend. It sounds great! This just reinforced how much I enjoy the 12lta. It's a wonderful driver. The sound is effortless and just sounds more alive than anything I've heard before.

Since the 12lta is on an open baffle and the 1808 is in a sealed box, my next comparison will be to put both drivers on an OB and compare. This will take a few weeks for me to build the baffles. I am not sure if I am smitten by the OB sound (or lack of sound) or the driver. At the moment, the victory goes to the 12lta.

The 12lta needs a good sub to keep up. The small Infinity is being pushed more than it was when mated with the 1808.

During my listening I noticed how realistic the piano and sax sounded on the 12lta. Also, you can really turn the volume up without any distortion. The driver is very efficient.

Sorry for the poor quality picture.

Zilla
 

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I had a friend who heard my AN10 stamped frame in a 70 liter/41H tuned (too low) reflex - he gestured to throw it out the window.... :D

AN10 did sound good in the original Karlson K15 cabinet - that improved balance, and reduced cone excursion. A smaller K-coupler than K15 for 12LTA could be built and 12LTA has a pleasant tone in K12 but K12 is a bit small for the weak 12LTA motor.

re:12LTA - all I have without loading and testing is a comparison some years back between it and the first model B102 - just on-axis in the old EV Aristocrat
An externally hosted image should be here but it was not working when we last tested it.


here's another typical Eminence (coaxial) speaker with similar moving mass to 12LTA, larger diameter aluminum coil. Both have similar sensitivity - I think there's a subjective difference - maybe the motor is stronger on the one on the right -?:)
An externally hosted image should be here but it was not working when we last tested it.
 
Sorry I was just giving my thoughts re the thread title and opening post for an 8" driver. Edit: Doh, just finally noticing it's an old thread and I was speaking out loud with regards to the first post. Me needs more sleep and a new brain lol... Carry on :)
 
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frugal-phile™
Joined 2001
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There is. Oil can resonance in polepiece cavity is eliminated (with phase plug, not as strong and up an octave with just the cap removed, and the phase plug pushes side to side resonance structures up by more than an octave and improve HF dispersion.

And also note that newer 12LTA have a much smaller whizzer than older ones. Mine are old (but i have treated a set of newere ones), i suspect Jeff’s will be of the older vintage as well.

dave
 
There is. Oil can resonance in polepiece cavity is eliminated (with phase plug, not as strong and up an octave with just the cap removed, and the phase plug pushes side to side resonance structures up by more than an octave and improve HF dispersion.

And also note that newer 12LTA have a much smaller whizzer than older ones. Mine are old (but i have treated a set of newere ones), i suspect Jeff’s will be of the older vintage as well.

dave
thanks for the response dave

ok. what diameter is the hole created by the removal of the dust cap in the 12lta? or what size must the diameter of pole plug be?
 
frugal-phile™
Joined 2001
Paid Member
ok. what diameter is the hole created by the removal of the dust cap in the 12lta? or what size must the diameter of pole plug be?

About 2”. I have used PVC plumbing pipe, i can’t remember whether it was 2” ID or 1.75” ID as quick & nasty phase plugs (install a thin wafer of wood at one end to affix attachment screws to.

Beta12LTAeN-Nat-wOrange.jpg


This is the newer driver. I expect the smaller whizzer would have better top end, but one would be relying on the main cone to go higher, and any whizzer resonances would be pushed higher. From size alone i’d estimate that if the old one starts rolling off at 5 kHz the smaller whizzer might reach to 8-10kHz?

dave
 
About 2”. I have used PVC plumbing pipe, i can’t remember whether it was 2” ID or 1.75” ID as quick & nasty phase plugs (install a thin wafer of wood at one end to affix attachment screws to.

Beta12LTAeN-Nat-wOrange.jpg


This is the newer driver. I expect the smaller whizzer would have better top end, but one would be relying on the main cone to go higher, and any whizzer resonances would be pushed higher. From size alone i’d estimate that if the old one starts rolling off at 5 kHz the smaller whizzer might reach to 8-10kHz?

dave

thanks.

someone on another forum mentioned using wooden chicken egg & 2 screws on the bottom for phase plug. found some w/ 1.75" outer diameter on fleabay so they might work.
 
Ideally the gap between phase plugs and the coils is as small as possible. With diy plugs you usually err on th eside of alittle too much to keep the plugs from rubbing on the moving coil (definitly audible)

dave

if 2 screws are put in the base of the phase plug & the plug width is as wide as possible, but not touching the coil, then the proper fitment is achieved by trial & error?

this sounds kind of hokey to me. it seems that a phase plug might slip off center & scrape the coil.

what about omitting the plug altogether or use a different more linear dust cap?
 
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