Infinity RS 2.5

 I’m glad to hear this news. Your explanation now makes perfect sense. The only way the the rear tweeters could play but not the front, was burned out tweeters. Fuses are much cheaper. Enjoy! You have some good speakers. 

@keyd1 - Excellent news! Enjoy the speakers. They are special.....

Hi, I found out what was going on with my 2.5's. I switched out the fuses which looked fine but were not. I put new fuses in and I the the rreqr and front tweeters work fine. I guess neither the front or rear were working. I am very happy about this. Thanks for your advice though. I have learned a few things.

This iPhone. Sorry for the typos.

Thanks. Actually I was to by the guy who refoamed the woofers that they were jumpered and they'veare. A thin wire to see. That's too bad. But thanks. I was hoping that may be explain the front tweeters not working. But no. There is only four screws in the tweeters. I will yakenthem outlet when I have some time. Getting mess up at my job. Have to pass a high level tof st in three weeks. Studying like crazy. Normally I would drop everything for this but cannot with this. I will message you again when I get them out. Thanks a lot!

If you are using a single amplifier, you need to run a jumper cable between each of the red (hot +) and each of the black (ground - ) binding posts.

From amplifier + terminal  -> red binding post on speaker-> other red binding post on speaker

From amplifier - terminal  -> black binding post on speaker -> other black post

The lower set of speaker terminals is for the woofers. The upper set is for the mid-range and tweeters.

Is this what your speakers look like?

http://www.infinity-classics.de/models/Reference-series-1+b-2-10+A+B-1981-86/Reference-Standard-2.5/RS2.5-11.jpg

http://www.infinity-classics.de/models/Reference-series-1+b-2-10+A+B-1981-86/Reference-Standard-2.5/RS2.5-3.jpg

If you hear rear EMITS, and front EMIMs and Woofers, the terminals must be jumpered together.

I know. I find that really strange too. I was just reading on one of the forums. Just new to this. Someone said, and it appears in the literature that using a single amplifier the speakers terminals  should jumpered. Mine are not. Do you think that could have anything to do with one tweeter not working on each side? Is this true, and important? Still doesn't make sense to me but thought I would ask. Thanks.

It is very strange that this is the case with both speakers, as the tweeters are all the same, and the front and rear tweeters are wired in parallel. 

Thanks. Yes, in both speakers. The tweeter should be as loud in the front as the back. Correct? On both speakers. There is no sound from the front ont tweeters. Left or right side. I will get in there and look. Not something I can do today though.

They are easy to R&R. You can check for loose connections without an ohmmeter. Is this problem in both speakers?

Here here is my guide to 1980s Infinity EMIT tweeters:

490125 is the rectangular EMIT with the thick magnet structure. 490126 is the same except for a round faceplate. Later versions of 490125 were labled 902-5086. Later versions of 490126 were labled 902-5023.

490123 is the rectangular EMIT with the thin magnet structure. As above, 490124 is the thin magnet structure with a round faceplate. Later versions of 490123 were labeled 902-2252. Later versions of 490124 were labeled 902-3082.

All of the diaphragms are the same, and thus interchangeable. The EMITs are easy to take apart (some Google work will show you how). Thus, when looking for replacement EMITs, look for a good looking diaphragm at a good price.

Hi, thanks for the quick response. Sorry for the typo. The front ones are not radiating, clearly. The rear tweeters definitely are very well. I am a bit of an amateur when tit comes to that. I don't have a volt ohm
meter either. I will have to pick one up. Are they fairly straightforward to loosen and take out and put in? Just don't want to run into problems putting them back in. Thanks. Appreciate it.

Both tweeters are supposed to radiate. Here is a schematic of the 2.5s

http://www.infinity-classics.de/technik/manuals/RS_2.5_technical_sheet.pdf

Loosen the front tweeter mounting screws and make sure the wiring isn’t loose. If it’s not that, check the disconnected tweeter with an ohmmeter - it should be between 3.2 and 3.8 ohms. If it is open, it is dead. If you need a new one, replacement tweeters are fairly plentiful on eBay.