AVS Forum banner
1 - 12 of 12 Posts

·
Registered
Joined
·
17,407 Posts
Discussion Starter · #1 ·
I have an Atlantic Technology 8200 system.


A couple of days ago, I was running REW sweeps on each of my speakers checking to see what differences could be found between them that could be minimized by the individual adjustment switches behind each speaker.


In doing the REW sweeps on one of the 8200LRs, I found that the frequency response above 4.33khz took a nose dive .


The crossovers are at 450hz and 3khz. I'm not familiar with what to look for if the crossover or the tweeter has gone bad, but I'd think that if it was the tweeter, the dropoff would begin at 3khz and not 4.33khz. I understand that crossovers are not brick walls but don't know if the filter slopes could explain the higher frequency drop offs. So I need someone to tell me if this sounds like a tweeter problem or a crossover.


The other possibility (after giving this a couple of days thought may be more likely) is that its one of these "acoustic optimization controls" could have gone bad.


Here's from the Atlantic Technology website.


A 3-position High Frequency Energy switch (changes the tilt of the tweeters response, not simply how loudly the tweeter plays). This allows much improved matching of the speaker's response to different room environments. Whether you have an acoustically live (highly reflective) or dead (highly absorptive) room, you can correct for varying acoustics. (Note: adjusting this switch in all three positions had no effect on the response curve)

A Location Selector switch shelves up both the upper midrange and the high frequency output to compensate for being located behind a perforated screen or theater curtains, providing unrestricted detail at the listening position. (Note: adjusting this switch did affect the response curve below the problem area)

A Boundary Compensation control adjusts for placing the speakers in custom cabinets or directly adjacent to a TV delivering open and natural sound.(Note: adjusting this switch did affect the response curve below the problem area)


I can pretty much rule out the boundary compensation control and the location selector as these appears to affect output below the problem area.


I'm suspect of the tweeter, the crossover and the 3 position high energy switch.


Its entirely probably that this speaker was defective from when I bought it 4 years ago and I just discovered it. Its used as a rear surround so its not like it was that noticable.


Would anyone like to make a suggestion as to what's the problem?


By the way, it weighs 53lbs so I'd prefer not to ship it back for repairs. Its more likely that it'd get damaged in shipment then I'd have to deal with that.


Thanks in advance.
 

·
Registered
Joined
·
2,227 Posts
Have you switched the speaker location to one of the other channels? That would rule some stuff out.
 

·
Registered
Joined
·
17,407 Posts
Discussion Starter · #3 ·
Thanks for responding.


I did test it with another amp channel which played fine with the other LR speaker. (these are used in the rear surround position). So I was able to eliminate the amplifier and wiring from being possible causes.
 

·
Registered
Joined
·
2,115 Posts
The problem sounds like it is with only one speaker and not the other.


Sorry if this sounds dumb, but swap the speakers and see if the problem follows the speaker.


By this, I mean pick them up and physically swap them.


If the problem follows the speaker--and you didn't swap the wires during the speaker swap--you know the problem is with the speaker.


If the problem followed the speaker, but you did swap the wires, swap them back. This can rule out all electronics outside the speaker.


If the problem did not follow the speaker when you swapped them and if you had swapped the wires during the move, you need to swap the wires back, to rule out all the electronics outside the speaker box.


If the problem did not follow the speaker and did not follow the wire swap, the problem is location related--a room mode problem perhaps.


Sounds dumb maybe, but you need to be certain that the speaker is to blame, and this is done by ruling out all other possibilities--move something and see if the problem follows. These are clues to help you narrow it down.


Let us know what happens.
 

·
Registered
Joined
·
2,245 Posts
As the "tilt" switch has no effect, than it, or what is connected to it ,is the problem. Look inside. It could be as simple as a fast-on has fallen off lug. More than that, you are in the realm of electronic troubleshooting. You are too far away to drop in. Sorry.
 

·
Registered
Joined
·
3,937 Posts
A more of a simple answer may be the tweeter is bad. Play some music with a good bit of treble and see if anything is coming out of the tweeter. Put your ear right up to the tweeter and find out what's coming out.
 

·
Registered
Joined
·
17,407 Posts
Discussion Starter · #7 ·
Passing Interest....I've already ruled out the electronics outside of the speaker (see post 3). And its definately not a null. Its definately the speaker ....meaning either the tweeter, crossover or associated switches.


tvgeek..I'll take another look at the wires coming out of the tilt switch and what they attach to. Its awfully tight in there and I don't honestly see how they put this thing together. Its almost like they put the speakers and crossover in place from the inside, then sealed the cabinet. ....crazy. Anyway, that's a good idea as I have a hunch that this has been this way from the very beginning and that could mean that a connector slipped off somewhere. Also might be worth checking voltages on the switch.


brandonnash....the tweeter sits between two mid range speakers. I can't tell what's coming from which. As I said in my first post the REW generated frequency response graph show a drop off at 4.33 khz while the crossover is at 3 khz. But you did get me thinking. If it was the tweeter, the dropoff would start below 3 khz so that the combination of the the mid and the tweeter would even out the response. This leads me back to the tilt switch and associated wiring and electronics.
 

·
Registered
Joined
·
3,937 Posts
Easy way of telling what's coming out of which driver is start with your ear next to the lower driver, in your case I am guessing the woofer and move your ear up to the tweeter. If the sound changes then you are probably ok. Just one thing to eliminate, and if that is the problem it should be a cheap fix. That's how I figured out my woofer was bad after taking a bad fall.
 

·
Registered
Joined
·
17,407 Posts
Discussion Starter · #9 ·
Figured it out....I think. (jim scratches head)


I found that the drivers do in fact mount from the outside (please stop laughing..lol). Made my way to the leads going to the tweater. They had voltage but no sound coming from the tweeter. Guess its a bad tweeter. Anything I'm missing?


Don't know if I should canabalize a tweeter from one of my other speakers that I'm not using. They're soft dome tweeters too.


The numbers on the back of the tweeter read Logic vifa 355-1811 DPB28. I imagine I can get one from Atlantic Technology but am going to look online from parts suppliers.
 

·
Registered
Joined
·
1,162 Posts

Quote:
Originally Posted by JimP /forum/post/16971343


Figured it out....I think. (jim scratches head)


I found that the drivers do in fact mount from the outside (please stop laughing..lol). Made my way to the leads going to the tweater. They had voltage but no sound coming from the tweeter. Guess its a bad tweeter. Anything I'm missing?


Don't know if I should canabalize a tweeter from one of my other speakers that I'm not using. They're soft dome tweeters too.


The numbers on the back of the tweeter read Logic vifa 355-1811 DPB28. I imagine I can get one from Atlantic Technology but am going to look online from parts suppliers.

The best thing you can do at this point is to swap the tweeters in the 2 speakers to see if the "bad" speaker does work properly with the tweeeter in the other speaker. This will guarantee that this is indeed the problem.
 

·
Registered
Joined
·
3,937 Posts

Quote:
Originally Posted by tsloms /forum/post/16971937


The best thing you can do at this point is to swap the tweeters in the 2 speakers to see if the "bad" speaker does work properly with the tweeeter in the other speaker. This will guarantee that this is indeed the problem.

Or if you don't want to go to that length of taking out a tweeter from another speaker you could always just unhook a woofer (only if it's easy to do so) and hook the wire to the woofer for just a few seconds to see if there's sound from those wires to the woofer. If so, the crossover is probably ok. Just contact Atlantic and they'll have a replacement. Glad it worked out for you and always remember, whatever's the most obvious problem is probably the problem. Glad it's something pretty easy to find. Figuring out if a crossover is bad gets a little more difficult.
 

·
Registered
Joined
·
17,407 Posts
Discussion Starter · #12 ·
Used one of the midrange drivers to verify that it was the tweeter. The mid put out sound when hooked up to the tweeter leads. This confirms that I have a bad tweeter.


Thanks guys.
 
1 - 12 of 12 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top