Axiom Home Page Forums General Discussion Technical Questions M80ti Crossover Problem (I think)

So I picked up a soundcraft mixer for some of the recording I do and decided to do an A/B comparison between it and a tube preamp that I've been using. Using the same signals to both preamps I drove one speaker with one and the other speaker with another.

What I immediately noticed was that one of the speakers had a punchier bass than the other and running specific audio tracks with extended low frequency showed an even greater difference. Out of curiosity, because my tube pre was literally kicking the soundcraft mixer's behind, I swapped the left and right channels.

Interestingly, the problem switched between the mixer and pre but not speakers. Thinking that it might be a problem with my stratos amp I switched channels at the amp, but the problem still persists in the same speaker.

Since all the drivers in the speaker work I really believe that the culprit here is the builtin crossover. Does anyone know where the crossover is located inside the m80ti speakers? I'm considering rebuilding it from new components to see what happens.

I believe it's directly behind the input jacks, but I've never actually looked.

You're right, I found pictures online which show that the crossover is directly behind as well. I'll take a look tomorrow to see if there' any obvious physical/electrical damage.

On a different note, I wonder if Axiom would be willing to upgrade my speakers with a newer crossover, for example I read somewhere that the original ti's don't even have a high pass filter on the tweeters.

You can buy a new crossover from them. I suspect that your info is wrong on the high pass filter, though.

Yeah, a tweeter would definitely need a HP filter or it would blow! I think you are mistaking the tweeter with the (midrange) woofers in regards to the lack of HP in the crossover on the ti's.

Rob, all the Axiom speakers have(and have always had)high-pass filters on the tweeters in their crossover networks.

In the case of the M3s that's all they have. Axiom wisely uses the mechanical roll off of the driver instead of a cross-over.

Sorry guys, I found the report (http://www.ninjasreview.com/forum/showth...-for-all-of-you) and it's the mid-range drivers that don't have a high pass filter and are allowed to just roll off.

I'm not entirely sure if it really is the crossover, but my cable lengths are the same to both speakers and since I've never played them extremely loud I can't imagine there being any damage to the drivers.

Perhaps I should call axiom directly.

Cable lengths wouldn't make any difference whatsoever. Did you put your ear up to all the drivers and make sure they're all working?

Yes, I've verified that all the drivers are working. The best way to describe what they sound like would be "muddy" and "hollow." Mind you, I was not aware of it until yesterday when I decided to A/B the preamp/mixer.

While the difference isn't extremely noticable it's evident when panning with the same material (mono signal) between the left and right channel.