Spendor S100 crossover question

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Hello dears,
thsi is my first post, and first of all please accept my apologizes for my poor english
I own Spendor S100 which seem to work fine. Woofres, midranges and tweeters work. Yesterday, just for couriosity, I took some measerements with a simple digital tester. While testing, the spekers were obviously disconnected from the amplifier
I try to test the continuty between + and - binding post, there is no continuity for the tweeters nor for the midranges, while woofers only show continuity. If I try to read impedance between + and - binding posts, the result is the same: no value for tweeter and midranges. Woofers show impedance of 7.8 ohm.
So I opened the back of the speakers to read impedance at the OUT side of crossovers. Here both tweeters shows 5.8 ohm both midranges 1.8 ohm (woofers show again 7.8 ohm). I have almost no technical knowledge, but I think that values taken measuring at the out side are not those seen by the amplifier

Is this behavoiur normal? Are values correct?
Please help me understand :)


I attach a picture to help me better explain



Thank you so much
Mauro - Turin - Italy
 

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I see bipolar caps there, so I assume that they may dry out over time. I have a pair of those Spendors as well, I would want to check those caps after all these years. Would those be low ESR caps when new ?They are bipolar as I see . My speakers seems to short some of the high frequencies. Bought them second hand and do not know how the have been handled :confused:
 
Welcome to the forum!

To measure the dc resistance of the various drivers with a multimeter you must disconnect them from the crossover. Remember that the dc resistance of a driver will be less than its nominal impedance.

You say your speakers are working fine, so I would leave well enough alone.

They say that curiosity killed the cat! :)

P.S. I should emphasise that your 'digital tester' measures the dc resistance of the driver and not its impedance (opposition to ac).
 
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I see bipolar caps there, so I assume that they may dry out over time. I have a pair of those Spendors as well, I would want to check those caps after all these years. Would those be low ESR caps when new ?They are bipolar as I see . My speakers seems to short some of the high frequencies. Bought them second hand and do not know how the have been handled :confused:

Hi
Those Bennic bipolar caps are in the woofer section
I too bought my S100 second hand (previous owner was the original first one) some years ago and I wrote Spendor asking about ageing of crossover components: they kindly replied that caps in this apllication are not stressed and they'd last forever
 
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