Ross Systems H-218CD speakers anybody? Mine are missing tweeters.

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Well, so far things are going smoothly :)

As of
I think you already have: *these* ;)

Fact is, Eminence is a *huge* OEM manufacturer on demand, they build whatever Customer orders, which can be *anything*
Besides that, and I personally think is an "extra", definitely not the main money maker at all, I guess they take a hard long look at their most popular products and make a few extra for "over the counter" sales.
Legends in my view are "civilian versions" of what they make by the truckload for Fender, Peavey, Crate, and 1000 others, and the "Greek" ones (Alpha/Beta/Gamma/Delta) an end user version of whatbthey make in bulk for PA manufacturers.
So if you look at your midrange speakers and find resemblance to "User" version Beta-something they probably *are* from that series.
On customer orders they could have been made in 2/4/8/16/32 ohm, painted pink or glitter metallic blue or whatever, using a dozen different cones, a dozen voice coils and so on, so don´t discard them just because they don´t *exactly* match one of the retail versions.
Plus: IF Eminence supplied the woofers, why not the rest?

My curiosity is mostly about the efficiency and frequency response of the driver. I guess i could measure it if it comes to that. I mean, in case some day i want a better treble solution, it would give me a target to shoot for.

I'm just about set up for speaker measurement though.
 
I'm just about set up for speaker measurement though.

I'd be interested in knowing what you are able to get for a response out of your fairly inexpensive pair.

You have me contemplating what service I should do with my set. I totally agree with the new caps as we all know how well they tend to age. I just don't know how much time I have to do stuff on mine but you sure are giving me an itch to do something. How is progress on speaker #2?
 
I scored a pair of these last friday for $0 and have been looking for info.
One works but has replacement mid range and no tophat. Piezo is Powerline.
Other has "exploded" transformer with bits stuck on woofer magnets and open circuit compression driver. Lack of information is frustrating and great to find info here. Original mid works and has black cone and brown cap (pushed in).
 

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Just added pictures of woofer. My crossovers look different and there is a single tweeter. I have seen one other picture like mine and it was called a 218 HL.
 

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Hey Coit, It is unfortunate there is so little information about these products out there. I too have scoured the web trying to find something of value. Yours are definitely different beasts than what I have with two piezo horns. According to usedprice.com yours were made around 1992 making yours newer than the h-218cd's.

Blown bits of transformer almost sounds like they plugged it into an electrical outlet...

I hope you are able to make yours return back to their youth. Or at least make something useful out of them. I am sure there is some reason you took on the daunting task of claiming them as yours. Good luck to you, and, have fun.
 
Thankyou for the quick reply. A friend is moving to Tasmania and had these in his shed. I couldn't get there quick enough. I will post more as things get done.
The mono and biamp wiring is a bit confusing. It's an inductor that's blown. It's labelled L2.
 

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You must have some plan for such "tiny" speakers. If there is anything I can help you with, let me know. Do your woofers and mids have a grey label on the magnet near the electrical connections with a code that starts with 67-xxxx?

Also I have to say that is a cool very vintage looking tweeter you have. Looks like they, in your revision, removed the painfully metallic sounding piezo horns.

Definitely an update with your crossover as well, mine have iron core inductor coils, and I see some of yours are air core.
 
Yes, bottom line: 67-8950-G or 61
top line I think: 180371 8ohm
I was thinking of putting Selenium compression drivers on treble horns.
Replacement mid sounds good. I don't think we have to worry about lack of bass!
I think he was penny pinching to reduce costs,eg: crossover boards can be used for your setup- still has 2 HF outs; place for T1 (never installed on mine).
Also neither of mine has any bracing, which will be installed.
Finally, I have no idea what I'm going to do with them. I've got a old iron 600W amp p.c. hooked up to one and keep sneaking the volume up.
Thanks
 
You can contact Eminence and ask what might be a good replacement part for your setup. They suggested a Sigma Pro 18a-2 for my woofer as I have one going a bit wonky. I haven't done anything about it yet... I am not sure if I want to spend that much on a single replacement woofer for a vintage set of speakers... as replacing the two speakers in one would cost more than what I paid for the two hurricanes. Sadly they have no re-cone kit for me.

Eric's shared photos are here:

Ross Systems H-218CD - Google Photos

Truthfully he would be best to ask about taking the cover off the back of the mid horn. You can read his post earlier about how he did it. Sounded rather painful to me as he described it in the post. As I recall it was well glued. So, good luck on that one! I think Eminence made the mid horn as a custom job, as it is a four ohm speaker, but sure resembles an Eminence product.
 
You mentioned yours are poorly braced. I was actually surprised at how well mine are braced. They make a nice solid higher pitched tone when rapped on the sides than other speakers I have had. In fact I have a set of Wharfedale monitors that are as light as a feather, rattle their front grill, and sound tubby with extra artifacts thrown in there when rapped on with the grill off. So I am not really concerned about them when I see a water bottle or other random stuff fly across the stage.
 
Thanks again for the reply. I got the mid cover off easily by running a sharp knife around the join (once I figured out where the join was).
I had another look at the old compression driver. When I stuck a battery on it, it buzzed. I installed it the working box and all the scratchy harsh treble is gone.
The sound is very good.
You blew me away when you said Eminence recommended Sigma Pro's. I have 2 18A's here that are virtually brand new that I've been trying to find a use for.
They are 1st gen. The woofers in the working box are good as far as I can tell.
More power might be a different matter.
The box sounds good without bracing, but I will add some for my peace of mind. If you needed mids the Alpha 6C's would be spot on I reckon.
 
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I think I disagree with the Sigma Pro's. They have such a short linear excursion they aren't able to reproduce lower frequencies very well at any volume. The H215cd's are reportedly to have a response of 37Hz to 18.5kHz +/- 4dB. The H218's should outperform that spec, I would think. But even with two Sigma Pro's in tandem I just don't see how they could. Perhaps someone could explain this to me. I do like the response of the Sigma Pro's from 100Hz to 300Hz. I do expect this system would need some rather sensitive woofers, as was mentioned earlier the goal was volume not fidelity. So, I get the dual 18's, and the compression mounted mid driver.
 
They are 8" mids, not 6". Also from what I can see they are 8ohm, not 4.
Dumb me.
My Sigma 18A's are in fairly large vented boxes and they really kick the bass out.
I have a sub design for them that's 3dB down at 38Hz, but I agree for low bass I would pick another Eminence driver.
 
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Really? 3dB down at 38Hz? Do you have a huge cut below that or do you keep the power levels to them very low? In their design ideas they suggest to keep power below 400 watts, and use a 24dB per octave high pass at 40Hz if I recall correctly to prevent over-excursion.

I thought the mids were an 8, but that is just a guess from looking at them. Are you sure they are 8ohm? Mine are definitely 4ohms.

If I do need to do something about this one woofer, I expect I will replace them all to keep things consistent. And, I may not even use an Eminence product as a replacement. We will see.
 
I was trying to read the faded label and thought I could see an 8. I agree, 4ohm would make more sense.
I wasn't saying my speakers are 3dB Down at 38Hz. It says that on attached plan from Jobst Audio- found on Speakerplans forum I think.
At present I have them pulled apart cleaning and painting. I will get one going with original mid and see what it sounds like.
Eventually will get 2 new mids and compression drivers. Will most probably tri-amp; not sure yet.
 

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