Speaker terminals - lugs
 

Speaker Relay Lug Size

Still looking at the 2205 speaker relay trying to decide how to wrap up Part-1 of the project. I've removed the new relay after installing it several days ago in order to measure the lugs with calipers. Here's a look at the old and new lug sizes:

OLD : 0.206" wide x 0.03" thick
NEW: 0.186" wide x 0.02" think (note thinner metal here)

The original quick connect non-insulated female terminals are 0.225" wide INSIDE where they slip over the lugs. I figure that what you all mean by "squeezing" is applying force to the SIDES with pliers, and not to squeeze them top-to-bottom. Will be checking that out today. Here is a pic of how much of a mismatch the new lugs are:


http://home.comcast.net/~mc_audio/MC..._terminals.jpg
Old quick connect non-insulated speaker relay terminals compared to NEW relay lugs.


Here is what McIntosh Service Dept. has to say about it:

"Thank you for your inquiry regarding the replacement speaker relay for
your MC2205. Yes, the relay lugs are now smaller which requires us to
squeeze the terminals to ensure a proper connection. The relay
manufacturer had changed the dimensions of the lugs roughly 10 years
ago; this change was approved by our engineering department. Since this
time, we have replaced many of these relays and have not had any issues
with reliability or performance using this method. If you are still
concerned with this connection method and also concerned with signal
path, you could eliminate the mechanical connection by removing the
push-on terminals and solder directly to the lugs. Either method is
acceptable.

I hope that you find this information helpful and that you enjoy your
MC2205 for many years to come."


There are still three options:

1) Squeeze the terminals to grip tighter.
2) Remove the terminals and parallel solder to lugs.
3) Remove and solder the correct terminals for the new lug size and thickness.

-Gregory

McIntosh owner for over 30 years.
--

A quick note to report that squeezing the speaker relay quick connect terminals from the sides will DAMAGE the terminals.. causing them to fold in half along the centerline. NOT RECOMMENDED!!

-Gregory

Have you solved the issue with the relay terminals ? I would take the relay to a local parts house and have them match the size. Some RadioShacks still have a good supply of terminal lugs. It is a common lug and should be easy to find. I WOULD NOT SQUEEZE THE ORIGINALS, YOU NEED ALL THE CONTACT AREA FOR CURRENT TRANSFER

Yes.. the problem has been solved since last summer. I used calipers to measure the lugs and from that, determind what size to order. The correct terminals for the NEW relay are: Noninsulated Female Quick Disconnect 0.187 x 0.020

They come in single or double-crimp barrel. Forget RadShak, order from McMaster Carr who stock Molex. Their shipping and service are excellent! The link to FQD Noninsulated is: McMaster-Carr


-Gregory