Searching for old driver info..

[DigitalJunkie]

Hello all,

I've a pair of 3-way speakers that I've been using for a couple years now,they were originally built by my father back in 1983-ish (~21 years old.) They've suffered a bit of wear and tear over the years,and I replaced the rotted foam surrounds on the woofers a few years ago.

I'm wondering if anyone can tell me a bit out the drivers used?
The driver lineup is:

Tweeter- Peerless KO10DT (I really like this tweeter.)
Midrange- Phillips/Becker AD5060SQ8
Woofer- Phillips/Becker AD10240W8

I found the tweeter in an older Madisound catalog,under a different model # (It sure looked identical,and specs seemed correct) but I think maybe this tweeter isn't being made anymore?

I havn't been adle to dig up anything on the Mid/Woofer..
Any help would be great! Thanks!

[kelticwizard]

Can't help with the mid. But here is the woofer, which the main cabinet will be devoted to:

Re=6.3
Fs=25 Hz
Vas=.127 cu meter
Qes=0.35
Qms=3.2
Sd=0.0315 sq meter
Pe=70 watts
Xmax=0.0043
Le=.001 Henrys
Diameter=10 inches
Mms=0.04433 kilogram
Bl=11.1 Tm
Sensitivity=89.5 @ 1M/1W
Qts=0.3155
?Accel?=252.5
Frame=Steel
Cone=Paper
Surround=Foam

[kelticwizard]

And here is a nice link to help with those conversions. I guessed at the units. All were Metric except the diameter, which was in inches.
http://www.onlineconversion.com/

[kelticwizard]

Don't look now, but that exact midrange is still for sale at Addison Electronics of Canada. It cost $14. I don't know if that is American or Canadian. The way the dollar is falling, it might not make much difference.

Page 13 of their catalogue:
http://www.addison-electronique.com/.../Section-A.pdf

[Jonathan Bright]

Hello Digital Junkie' the tweeter and mid were marketed in Australia some years ago.

My data for the mid is as follows.
Freq range 180 c/s to 10 k although some of their material suggests 12,500 c/s
The resonance is 210.
Sensitivity is 90 db/w/mtr
Power handling is 40 w rms with a cross over of 500 and 4,500 cycles, these were 1st order slopes. One local factory design used an elliptical filter at 600c/s.
They were available in 4 and 8 ohm versions and the 8 after the Sq indicates yours are "8's". The "Sq" stands for "squawker" which some people used for mids.

KO 10 DT is a one inch dome.
Max input 10 watts sine way above 1500 c/s
Sensitivity is 92 db/w/mtr/
Resonsance is 1,000c/s
Rf range 1,500 to 20,000
air gap induction 15,000 gauss (1.5 Wb/m2)

That's just read off a couple of factory data sheets I've got.
I too like that tweeter but like many domes it may profit from a 3db notch filter at about 13k Hz.

[DigitalJunkie]

Wow! Thanks guys!

It's nice to finally know what the power ratings of the drivers are,a bit lower than I expected,but seems about right..
I was correct in my notion that they were a tad low on the efficiency side.. (The tweeters and mids have L-pads to adjust the levels down to match the woofers.) They do like a bit of power,but even my 8wpc tube amp will get them up to bedroom-rocking volumes.
I'm also kinda suprised that the power handling seems to be lower than I had thought....They seem to hanle alot more than "only" 70W.
I seem to recall the tweeter being rated at 100Wmax @4khz X-over point with a 12dB (2nd order) slope..I think it dropped to 50W max @ 2khz.

Crossovers are all 12dB/2nd order.. I'm unsure of the crossover points,but I do have a schematic with all the component values,so I can figure it out..

Cool! Thanks again!

[DigitalJunkie]

(DOH! darn post-edit time limit got me..)
Hopefully you can mentally paste this into the above post so it makes sense..
--
It's nice to finally know the power ratings of the drivers,but I'm also kinda suprised that the power handling seems to be lower than I had thought....They seem to handle alot more than "only" 70W...
My father said he had cranked them on 200W amps and they still sounded great,....untill the tweeters blew.
Dad had made a few pairs of these speakers up (this pair were the "prototypes") and sold them to friends and stuff way back when. (~20+ years ago,when Vance Dickason had a shop here in Portland,guess he and Dad were kinda pals.)
He said a couple people blew thier tweeters out running them up to like 200W,so he added tweeter fuses when replacing thier tweeters.So,I figure aslong as I don't melt the tweeter fuses I should be OK with cranking the volume up..