Guest fscott Posted May 7, 2009 Report Share Posted May 7, 2009 Finally got around to installing the crossovers and hooking up the one midrange and tweeter I have to test them out. The midrange sounds good, but the tweeter has very little output, and I hear a slight bit of intermittent "rattling" like something may be lose. The output is so low that the "rattling" is about the same volume so its difficult to say if it's rattling or even static I don't know. The tweeter's resistance is 2.0. This tweeter has the original aluminum leads and at the moment it is wired with reverse polarity (the yellow terminal is going to the negative side). Would that be the issue? I didn't want to disconnect the leads since they're apparently difficult to hook back up. They've been on there since the speakers were new.I purchased a used dome tweeter but its not here yet so I can't make comparison. But the output really is very very low. Wires all have good connections. Link to comment Share on other sites More sharing options...
genek Posted May 7, 2009 Report Share Posted May 7, 2009 Finally got around to installing the crossovers and hooking up the one midrange and tweeter I have to test them out. The midrange sounds good, but the tweeter has very little output, and I hear a slight bit of intermittent "rattling" like something may be lose. The output is so low that the "rattling" is about the same volume so its difficult to say if it's rattling or even static I don't know. The tweeter's resistance is 2.0. This tweeter has the original aluminum leads and at the moment it is wired with reverse polarity (the yellow terminal is going to the negative side). Would that be the issue?Crossed leads is normal, and while 2.0 DCR seems a bit low, I've seen perfectly good tweeters measure as low as 2.5; depending on what meter you have, you could be venturing into the inaccuracy zone. The rattling suggests that there might be a voicecoil problem.How low is low? Under normal conditions it is often necessary to use a stethescope or a cardboard tube from a roll of toilet paper or paper towels to distinguish tweeter output from the rest of the system. Link to comment Share on other sites More sharing options...
Guest fscott Posted May 7, 2009 Report Share Posted May 7, 2009 A stethoscope? Well I'd say that's within the ballpark then. The rattling is what's really concerning... Link to comment Share on other sites More sharing options...
RoyC Posted May 7, 2009 Report Share Posted May 7, 2009 How low is low?That old orange dome used in the AR-3 and 2ax was indeed a low 1.9 or 2 ohms DCR!Roy Link to comment Share on other sites More sharing options...
Guest fscott Posted May 9, 2009 Report Share Posted May 9, 2009 I determined that hooking up an amp with just the mid and tweeter and then pushing more power is hard on the amp and speakers. I decided that the "rattling" was actually clipping from the amp. So no more push the volume to the wall without all the components installed scenarios! Anyway...I received the other dome tweeter today so I was able to compare them. The new tweeter has louder output. I tested the speakers by hooking up to the rear terminals and directly to the front terminals. In both cases the new tweeter was noticeably louder.The new tweeter also tests right at 2.0 DRC. However, the aluminum leads on the new tweeter do look better. Would "cleaner" leads possibly contribute to the tweeter having more output even though I tested their resistances at the lead ends and both were 2.0? Link to comment Share on other sites More sharing options...
Guest fscott Posted May 9, 2009 Report Share Posted May 9, 2009 One additional thing - not sure if this helps...Since the tweeters are both now connected to the terminals I didn't want to take them off so I tried some resistance measurements.I measured the resistance on the terminals for each tweeter. With the tweet pot at full volume: The louder tweet measured 9.0 ohms and the other tweeter was 1.7 ohms.With the tweet pot off:Both were at 0 ohms or near zero.In both cases the mid pot didn't affect the resistance whether it was full on or off.Like I said, not sure if that would give a clue into whether there is something wrong or not. Link to comment Share on other sites More sharing options...
RoyC Posted May 9, 2009 Report Share Posted May 9, 2009 If both tweeters have the same dcr there should not be that kind of discrepancy. Check your crossover components and wiring.Roy Link to comment Share on other sites More sharing options...
Guest fscott Posted May 10, 2009 Report Share Posted May 10, 2009 Well I just disconnected a lead from each tweeter and tested the output directly. The new tweet is still significantly louder - in fact it's how I originally thought the first tweeter should have sounded, and thus causing me to create this topic. So even though their DRC is nearly the same, (tested again 2.2 and 2.0), the output is significantly different. Lesson be learned I guess, DRC isn't the only significant variable.And with the tweets out of the loop, the little experiment I did above, now shows identical numbers. Why in the world one tweet would cause such strange readings even though their DRC is the same is beyond my pay scale. Link to comment Share on other sites More sharing options...
RoyC Posted May 10, 2009 Report Share Posted May 10, 2009 Well I just disconnected a lead from each tweeter and tested the output directly. The new tweet is still significantly louder - in fact it's how I originally thought the first tweeter should have sounded, and thus causing me to create this topic. So even though their DRC is nearly the same, (tested again 2.2 and 2.0), the output is significantly different. Lesson be learned I guess, DRC isn't the only significant variable.And with the tweets out of the loop, the little experiment I did above, now shows identical numbers. Why in the world one tweet would cause such strange readings even though their DRC is the same is beyond my pay scale.You may be dealing with 2 different issues...Inconsistent output/response is not an uncommon problem among the old tweeters. There are some folks in denial about this issue, but it is real. On the other hand, a .2ohm difference in dcr is insignificant, so it is unlikely the tweeter caused your crazy meter readings.Roy Link to comment Share on other sites More sharing options...
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