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Speaker terminal polarity

I just unpacked my Cary 300B-SE mono blocks after being in storage for over 15 years.  Both speaker outputs (on each amp) look identical (not color coded) and neither is labeled + or -. I tried a continuity test against the amp chassis and both terminals read the same. How do I determine + from -?  Does it matter as long as I have each amp wired to its corresponding speaker the same way?

I must have asked this question when I got the amps 17 years ago, but can't locate the thread.  Standing by with red and black sharpie pens if necessary.

jamesddurkin
oldhvymec
5,101 posts
 
ALL of his stuff is the same way that I have. Smart actually. Yea warm those up and give them a good listen... 15 years is a long time, ay..
Keep a close eye for a FEW days ay.. Sniff and look for oil leaks, not kidding, Carys are like old Harleys, they will leak oil, LOL twice for me.
They use that same 560uf  X ??? VAC for the filter caps..

I got mad at the dog at first.. Got a quick pat on the head.. oil, no dog piss, heart attack time.. 

Enjoy..
speakermaster
738 posts
 
On an old cary amp the base of the post is colored red or black it is not marked in the usual fashion look closely you will see it.
ecscott482's avatar
ecscott482
44 posts
 
Place a 1.5 volt battery across the speaker inputs. 
If the speaker cone moves out, label the positive battery side connected to the speaker +   

If it move in, then label it - 

Do the same for the other speaker.


jimofmaine's avatar
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jimofmaine
40 posts
 
I'd suggest to judge correct polarity by ear. Do a simple listening test: 1) connect your speakers up to your amp. Play a track with vocals. 2) Then ON ONE SPEAKER only, switch the positive and negative wires and listen again. The wire orientation that sounds the most focused, voice in between your two speakers, is the correct polarity, regardless of what colors or what you think is +, -.

barryaudiophile
57 posts
 
Your question about absolute polarity is important.  In an ideal world a recorded kick drum when hit will cause the air to move toward the listener.  This will happen if phase integrity is maintained throughout the audio chain.  The audible effect is call the Wood Effect. Look it up on google.
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