Monitor Series 2 m4 vs S20s

JonathanRichardson

So I had a pair of S55's as my mains in my apartment and now my house has a built in shelf entertainment center that doesn't fit the towers. I still have the my S30 and will most likely purchase a pair of S20's to use as mains.

That said, I picked up a pair of monitor Series 2 m4's a few years ago off Craigslist for $50 to use as satellite speakers, but are now currently running as my mains. They don't sound horrible by any stretch, but the sound seems a bit washy, almost what i would describe as out of phase, or poor imaging.

This leaves me questioning two variables, are these speakers just crappy, is my room/cabinet throwing stuff off, or is it a combination of both.

Anyone want to weigh in on what the impact of the replacement of S20's might do for me from these

pkquat

Sorry I am not directly familiar with the S20's or the M4 Series 2. I am pretty sure the M4 series 2 is the "M4s" in the schematic section and it uses the M1500 tweeter. It is the rectangular tweeter with the horizontal bar in front of it. I don't think there is a drop in replacement for than model tweeter, although it may be possible to rebuild the crossover to use a later RD0-198 tweeter if the tweeter base plate mounting pattern is the same. It appears the main inductor, L1, is the same between the M4s and M4.6.

The schematics are here: https://forum.polkaudio.com/discussion/38755/polk-audio-speaker-wiring-schematics-more-all-models-except-sda

I do have some model M4A's and they have good imaging. It could be that the capacitors or resistor in the crossover have started to fail, or possibly someone had them apart and something is connected out of phase. I would check that first. There is also a chance one of the tweeters is starting to go bad.

I believe the MW is the 6502. This driver is used in many vintage models and sounds great. I am not sure how they will match with the S series speakers as far as sound. I think they do ok for the timbre match. I don't think the M1500 is a great tweeter, but I think it should be ok. The square plate "triforce" tweeter used in the M4A is not a "great" tweeter, but I would call it very good in its paring with the speaker. It is not an smooth and detailed as the peerless tweeters, or the later RD0-198, but it is still detailed and easy to listen to for extended periods. I would hope the M1500 would be close to that.

cfrizz

Welcome to Club Polk. I would bet that it's the cabinet, speakers don't belong inside of them, they need room and space to let the tunes out.