15 in full range drivers

Every example limps as the saying goes. But anyway, below is Paul Miller's measurements of the Lowther Almira which uses an eight inch DX3 driver supplemented by a supertweeter. I've never hear a "full range" driver which uses a whizzer cone to extend frequency response that didn't sound ragged. A 15in driver is going to be very compromised in the midrange - more than the Lowther driver.

The best sounding efficient loudspeaker I've personally heard is the Devore Fidelity 096. Expensive, but properly engineered to perform with low powered amplifiers.

I'm curious about the cabinet design... did you buy plans?

Bass reflect single port 43 in tall by 20 wide and 18 deep. 1-1/2 in thick walls.  Solid and heavy..

@zagorskia

I see this is a paper cone. Is there any coating on it? C37 lacquer

Used this on my untreated paper cone F-R. Figured I had nothing to loose as the breakups made it un-listenable. Had it shipped from Austria.

Put on 1 coat and still harsh. So took a chance and put on a second coat as Dieter recommended and sound was good. Subjectively, I think prefer it over Nextel as it is lighter in weight and more beautiful tone to it. Although I would had to hear side by side, before and after, to say for sure.

You can coat most anything with it. Except for tubes. Haven’t tried the C37 lacquer ear drops yet, haha. (that is a joke)

Evaporation is a problem and even though I stored it in its original container in the refrigerator, it still evaporated.

With certain music, (vocals) they are beautiful, but other music can be fatiguing.  Wife can only take them at lower volumes.

@zagorskia This is unavoidable if you do not have a crossover.

I know that a crossover is anathema to 'full range driver' users but its a fact due to something called Doppler Effect Distortion. In a nutshell, this is caused by bass notes on the diaphragm, so as the driver reproduces higher frequencies, they are being moving back and forth as the driver attempts to play the lows.

That is why woofers are used.

If you cross the driver over at 500Hz and use a woofer for 500Hz and down, you'll notice that at higher volume levels the 'full range driver' is considerably smoother and easier to listen to.

You may have noticed how beamy the speaker is at high frequencies- such that only one person can sit in the sweet spot to really hear the soundstage right. To get away from that you need a tweeter- and a crossover for it, keeping the highs for it out of the 'full range driver' so as to prevent combing effects (which come off as harshness).

IOW, 'full range drivers' are really extended range midrange drivers.

Do I go with new speakers or keep suffering?

If you continue to try to operate without crossovers, you will continue to suffer... you may have noticed I use quotes around 'full range driver' because there really is no such thing. To make them work right you need a woofer and a tweeter.