Eltax Century 200 - Speaker & Wiring Query

[Damselfish]

Hi All,

Hoping you can help me out. Have done a quick search on this but to no avail so here goes.

I have recently been given a pair of Eltax Century 200 floor standing speakers. 3-way ported config. 80w RMS @ 8Ohm.

When i plugged them in i found that both tweeters have blown. 🙁 .... no wonder they were being given away!

Also, one has significantly less bottom end, hmmm. The woofers seem to be okay, as does the capacitor between the top woofer and the tweeter - tested with a multimeter

I'd love your opinion on the following please?

1. Is it worth me sourcing replacement tweeters or would i be better off scavenging them for working parts? No idea if these units are any good or not.

2. Why would i be getting less bass from one of the units?

3. Having pulled the drivers out to inspect, the exiting blown tweeters don't have + or - on the terminals - does it matter which way they are connected (other than potential phase issues - although led to believe this would be nominal for tweeters)

Below is a wiring diagram I've put together (apologies for my poor drawing skills - hope it makes some kind of sense!) - hopefully that will help make some sense of the config / wiring.

S1 & S3 = Woofers
S2 =Tweeter

If any other info would be useful then please let me know - newb to speaker electronics / wiring here 🙂

Look forward to hearing from you, and thanks in advance.

Tim

P.s. Looks like someone had been in there before me so can't vouch for whether the wiring is how it should be
P.p.s I'm usually on the mixing desk, not poking about in stereo speakers so please be gentle and excuse my ignorance 🙂

 

[AllenB]

The woofers are in series. Try moving the cones with your hand to feel for resistance. Measure the coil resistance of each.

does it matter which way they are connected (other than potential phase issues - although led to believe this would be nominal for tweeters)

Either way will function. One way will likely sound better.

 

[Damselfish]

Thanks Allen

Cones of the woofers feel fine and the same across all 4, not loose, not crunchy/scratchy in any way

Measured the resistance and got the following results - see pics - does that seem about right?

Gonna be a case of using my ears on the tweeters - although if I can't sort the bass mismatch between the two boxes it may not be economical to do so.

 

[AllenB]

Those two woofers look fairly close, but it’s still possible to have a shorted coil turn with little difference in resistance.

 

[planet10]

Eltax Century 200 floor standing speakers. 3-way ported config

IK havbe redrawn the XO in a more conventional manner. Woofers are wired out-of-phase so no bass is expected. Tweeter XO is a nominal 9kHz.

It is a 2-way MTM. From what i see i’d guess these are "white van" speakers. XO is only a single cap, and at a strangely high frequency. I bet the enclosiure is unbraved thin chipboard?

dave

 

[Damselfish]

Those two woofers look fairly close, but it’s still possible to have a shorted coil turn with little difference in resistance.

Thanks Allen, they are working, just when wired into the cab i get a big difference in the bass response from that side.

 

[Damselfish]

@planet10

Those are the boxes in question.

Thanks for putting the wiring diagram together, way clearer than my scribble 🙂

Sorry for ignorance but what is "MTM" and "white van" speakers ? The enclosure is indeed unbraved thin chipboard 🙂

Is the lack of bass issue on that enclosure likely to be the out of phase woofers then? If so, do i solve by reversing the connections on the lower woofer?

To be fair, i've not yet traced the wiring in the second enclosure which has the bass end as i think it should sound, i.e. full range, so entirely possible the enclosure with the issue is just wired up slightly backwards! 🙂

 

[Damselfish]

Update: So swapped the connectors over on the lower woofer and i now have full bass response from both enclosures.

Thanks for the heads up on the phase issue @planet10, that's sorted it. 🙂

Just got to source some replacement tweeters now and they'll be back to fully working.

Thanks gain for your help, completely invaluable!

 

[planet10]

"MTM" and "white van" speakers

Midbass-Tweeter-Midbass. "White van speakers” are really cheap loudspeakers sold out of the back of vans (often white).

Given the first order XO all drivers should be wired in the same phase.

If you want to play and learn, brace the box, add a new baffle over the old one, get the drivers as close as possible. If the tweeters are indeed blown, you will neednew ones, and work out an XO.

I expect they could be made WAY better.

dave

 

[Damselfish]

Thanks Dave, that makes sense. Never heard the term white van speakers before - every day's a school day!

I'll source some new tweeters and see how i get on, like the idea of using these to play and learn and try to improve on them.

Thanks again for all the help.

Tim