15" midrange???

[borus]

I have this pioneer 15" driver that test like it's a midrange. Testing shows the woofer hits 62DB at 20Hz but 113DB at 1200Hz. This thing is backwards. It climes steadily up to 1200Hz then drops like a rock. It would seem normal if it was a 6" driver but even then I would think the lows would have more power. The driver finally gets into the high 80's DB at 250Hz.

I know I have read some ware in the past

that some of that high frequency energy can be looped to enhance the low end but I can't find the info. I may be thinking of low frequency energy enhancing the highend in a tweeter circuit but I seem to remember It could be used both ways or in reverse. Anyone know about this? Or any other Ideas to get some use out of this driver. The pioneer was a "AS" box (sealed)

Any help here? Thanks Borus

 

[mhardy6647]

1) Does it have an accordion-edge surround? If so, it might be an MI driver with a high Fs and very limited LF response. Did you measure Fs?
http://sound.westhost.com/tsp.htm

2) I have an EV SP12B that essentially performs as a midrange driver. Why?, I hear you ask. It is probably suffering from a malady known in the trade as "crap in the gap"; there is either crud in the gap that is interfering with the travel of the VC/former in the gap and/or the VC/former are distorted (probably from over-powering) and are themselves binding in the gap. The cone has very little excursion but the VC is still operating. The net effect is a 12" twin cone driver that sounds like an old-fashioned 4" tweeter.

Just my knee-jerk thoughts on the matter, you see.

 

[bowtie427ss]

I have this pioneer 15" driver that test like it's a midrange. Testing shows the woofer hits 62DB at 20Hz but 113DB at 1200Hz. This thing is backwards. It climes steadily up to 1200Hz then drops like a rock. It would seem normal if it was a 6" driver but even then I would think the lows would have more power. The driver finally gets into the high 80's DB at 250Hz.

Are you testing the driver in a box, or in free space?

 

[djnagle]

It might also be just old. Sometimes you can let it play for a day or two and get it loosened up a bit.

 

[ROSSO]

Two more cents: Ditto above. Sounds like a sound reinforcement or musical instrument speaker - designed to play loud but not particularly low. 15" dosen't necessarily mean it'll do sub 40 hz. Can you find the model number in one of the free on-line bass-box modeling programs? That could help predict what it should do in an enclosure.

 

[Stuart Pedaso]

You could mount two of 'em vertically in a box with a tweeter between for an MTM arrangement.

You'll just need BIG driver at the bottom to handle the bass ... :scratch2:

 

[dumptruck]

find that model number and/or take a pic - there's too many possibilities.

 

[borus]

Update

This woofer is outside its box. It has an accordion-edge surround. It came out of an old pioneer CS-63 earlier than the DX series loudspeakers. I do not know how long they sat idol. The model # of the woofer is PW382-1. 15" with alnico magnet. I believe this was pioneer's top model in 1968. I know they are the best built Japanese speakers I have ever opened. 1" plywood walls. The crossover is well made. Maybe not the best components but well thought out. See Pics

 

[RayW]

How are you testing the speaker? If you just have the driver itself in freespace and you're doing a sine sweep or something similar then you're not going to get any low end. You'll get cancellation from front to back very high up. Mount it in a box (which will skew the result toward the box tuning but will give an idea of what the driver can do) or in a baffle to see what the low end looks like.