Upgrading SL1000 tweeters

mrcircle

Hi all,

I've been enjoying the heck out of my Monitor 10s after having Westmassguy rebuild the crossovers (thanks again, David!) and performing all the upgrades he recommended. So much so that I'm now planning to do the same with a pair of Monitor 7s.

The 7s have SL1000 tweeters, which I know should be upgraded. The question is, with what? If I understand correctly, the SL1000 tweeter is the same size as the original Peerless tweeter but electrically the same as the SL2000/RDO-194.

After reading through numerous threads here, it seems that if I want to go with the RDO-194 (or RDO-198, as I did with the 10s) I'll need to alter the mounting hole in the baffle. Is there any reason not to use Peerless tweets instead, if I can find a working pair?

I know this has probably been done to death already but I have found a lot of conflicting information and wanted to see if the Polk brain trust could give me a definitive answer.

Many thanks,
Michael

Faustin

I would check the current values of one of your 7's crossovers and compare it to the schematics to see if the Peerless will work. I don't think there were any differences between the c/o's from the Peerless to the silver faced SL1000, other than perhaps fused vs polyswitch and a minor change in the resistor. I am sure others will chime in.

pkquat

I really need to write this stuff down, or list / pdf should be created for this. As I recall, the MW is different as well as the crossover between the peerless version. I think the crossover should follow the 7B_orig schematic which is why the 194 is recommend as the replacement.

I know some people have found peerless tweeters or used the Midwest Audio peerless knock off, got the correct MW, and rebuilt the crossover to match original 7's.

westmassguy

Michael, the RD-0194-1 is the correct replacement tweeter for the SL1000. The recess in the front baffle must be modified, or the lip on the back of the plastic escutcheon can be removed and the 194 surface mounted.
The SL3000/TL Modification can be done on them, unless they're really oddball.

mrcircle

Thanks, guys. I'll take westmassguy's word as gospel here. Guess I'll figure out how to rout out the opening to make room for the replacement tweeters when the time comes. (I'll be in touch about the crossovers then, too).

Cheers,
Michael

xschop

To properly sink the RD-0194 to baffle depth requires a 0.135" channel widening that encompasses the factory tweeter baffle area.

mrcircle

Good to know, xschop. I've got a good friend with a pro wood shop I'll be calling on when the time comes.

xschop

And at least a depth of 0.275" to allow for a decent thickness gasket.
IMO the 194 is not worth the hassle as the SQ is just ok. Better than SL1000 for sure.