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Cerwin Vega speaker help needed

On the A/B speaker thing. I think you misread what I said. If you have the A speakers connected and playing, then (leaving the A button alone) press the button to activate the B speakers, on some receivers/amplifiers the A speakers will go out. On these receivers, when using both A and B, they are run in series, and with the B terminals connected to nothing, you have an open circuit and that's why the A speakers go off. I've run across this many times, and stand by what I posted.
On the dust caps, Assuming you're not swapping caps of significantly different weight which would effect the t/s parameters, I also stand by my statement that they won't change the sound, especially in this case where we're talking such a small difference. Could test equipment measure some slight difference? Possibly. But test equipment can measure individual atoms these days. I will admit I don't know everything, so if you have any info to the contrary, I'm happy to be schooled any time.
On amps. The Bogen HTA-250A runs 250 watts rms, less than 0.5% total harmonic distortion from 20 to 20,000Hz. Before you say anything, I'll agree that those basic specs don't entirely tell the story of how an amp will sound. I was just putting out there that many people looking to put a system together, might consider commercial or pro amplifiers. We can't all afford Krell. I picked up those Bogens for $100 including a ton of other stuff. So basically for nothing, I have a system with a solid 250 watts per channel. My Biamp 650 is 325 per channel and cost almost nothing. And those amps sound GOOD!
My "best sounding" system, to me anyway, is Nad driving JBL's. I'm really really happy with it. And if I was going to study the timbrel differences between violins or something, that's what I would use. But when people come over and see monster Cerwin Vegas, they want to hear Molly Hatchet pounding them to the bone. For that, you need watts. And commercial/pro amps deliver those, sound great, and can be found for really cheap. I'm on a budget here as many are.
 
Fired one of the 1230's up today to do a "side by side" with the Optimess speakers. Didn't sound completely terrible, but not as good as the real CV. Could hardly hear those "mids" working. Tweets were more "canned" sounding. And woofers were "different", not as much low bass.maybe, and too present at some mid frequencies. Still need to find out what correct mids should be?
Also wondering if I should attempt to refoam my W121 myself with a signal generator phone app. (the local guys want $30-$55/speaker, and at least 1 removes the dust cap). I'm pretty handy with repairing stuff, since everything I own is old and requires maintenance (including me).
 
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cimchazz1 said:
Fired one of the 1230's up today to do a "side by side" with the Optimess speakers. Didn't sound completely terrible, but not as good as the real CV. Could hardly hear those "mids" working. Tweets were more "canned" sounding. And woofers were "different", not as much low bass.maybe, and too present at some mid frequencies. Still need to find out what correct mids should be?
Also wondering if I should attempt to refoam my W121 myself with a signal generator phone app. (the local guys want $30-$55/speaker, and at least 1 removes the dust cap). I'm pretty handy with repairing stuff, since everything I own is old and requires maintenance (including me).
Click to expand...
Ever replace a car gasket? Spent some slow patient time scraping the surface clean? If you can do that, you should be able to do this.
I use a mp3 player, 30Hz tone file I made in Audacity and a lepy 2020a amp. Never pulled a dust cap. I did do a CV 10" that had a messed up voice coil I needed to use clothes pins on, other than that it's mostly about patience.
 
Thanks, I can be VERY patient if it saves me 100 bucks! I've changed many gaskets and rebuilt many engines. Actually, the surfaces are clean and scraped. I might want to clean the cone edges a little better with something.
 
All depends on the situation. Different speakers, different glues... Best tool for cleaning up the speaker baskets on my Advents was a flat head screw driver.
My brother had really screwed up his Cerwins I refoamed so I don't know how it is with Cerwins, but the best tool I've found for cleaning the cones is an Xacto knife.
31NZJNZaYqL._SX342_.jpg
 
Usually denatured alcohol works well to soften up the foam/glue residue on the cone. Apply some alcohol and usually it just wipes off with a rag. The frame you can scrape with whatever works. You can also use a wire wheel on a dremel to really clean it up nice and shiny. (wear your safety glasses)
On centering the voice coil. I know a lot of people recommend and use a signal generator. I don't. I looked into this in depth once. Using a signal generator will move the cone up and down, and as you are adjusting the placement of the foam on the frame, this will help you verify that the coil is not rubbing in the gap. However, there is nothing in the physics of interaction between the two magnetic fields that "pushes" the coil to be centered in the gap. The magnetic interaction is only pushing that coil up and down, not sideways. Again, that method will only serve to verify the coil isn't rubbing. But, the coil could be 99% to one side and not rubbing. Under heavy load (max watts) any flex in the cone/spider or uneven weight distribution could cause that coil to rub. And over time, gravity will cause slight sag in the foam and spider. If you start out a hair from rubbing, over time you could get a rub. And obviously rotating a logo'd cerwin driver has the asthetic drawback. The way I do it is by feel. You can use a slower setting glue from the foam to frame. As the glue is starting to tack up, I'm pushing the cone up and down (like the signal generator would) I force it back and forth from 12 oclock to 6 oclock, from rubbing point to rubbing point, noting the foam/frame relationship at both rub points, then where the middle is. Then do the same with the 3 and 9 oclock positions. Keep doing that as the glue is setting. This gets the coil not only to be not rubbing, but also as centered in the gap as possible which is what you want. It's the difference between working, and done as best as possible for long term rub-free operation.
Now I know I'm going to get "No, your wrong, the signal centers the coil". If anyone has proof, I'm all ears. It would be in the physics, meaning the interaction between the lines of force of the magnetic fields. I've looked. Can't find anything to support this. And driver engineers spend a LOT of time studying the interaction of magnetic fields. (overhung, underhung, shorting rings, etc.) Think of it this way, if the magnetic fields centered the coil, you wouldn't need a spider.
Thankfully Cerwin woofers have a pretty big vc gap in relation to coil thickness. So there is a ton of slop to play with. Making them easy to refoam. Some JBL drivers on the other hand.... ugh! just a few thou.
If you rebuild engines, you can refoam! You go slow and careful not to ding your crank journal right? Same with this. Slow and careful. I use artist paint brushes to apply the glue to the cone edge. and also to the foam underside. The glue on the cone, leave it "out" from where the inside lip of foam goes a bit so you don't have any slop on the cone. On the foam, glue right to the lip. Having "glue to glue" ensures a great bond at the very edge of the cone where the stress (pull when the cone is farthest inwards) is. It's why good tile guys "backbutter" tiles. Also, before gluing the foam to the cone, you can put a bunch of bits of blue tape, with corners of the tape evenly spaced around the cone just a hair inside of where the inner lip of the foam goes. That way when you drop your foam on to glue it to the cone, you get the foam on evenly all around centered on the cone. Same thing if you have to do a dustcap. Measure down from the foam inner lip and get a circle of tape bits just outside of where the cap goes because once you glue it and plop it on, you can't move it without glue slop showing. I see a lot of repair jobs where the cap is clearly not in the middle. And of course, if you look at cerwins a lot, people don't pay attention to the indexing of the logo cap, so when you bolt in the woofer, the cap isn't straight.
I wanna hear that you ordered some foams now.... :)
 
Thanks CJ for the info on the refoaming. I think the signal generator (in the article I read) helps you know when you are centered by the variation in tone intensity. Of course I will not really understand how it helps until I try one myself. I already tried removing a dust cap on a CV to replace it with a smaller one to match another speaker I had, and that didn't come off very clean, but I used "Goof-Off" adhesive remover. Maybe the acetone of denatured alcohol would have worked better?
Anyhow, I have these 2 speakers now to learn on. Not too worried using them because full rebuild kits are easy to find for 50 bucks, but I would like to keep these original. Heck, if I can find someone local that will do it for $20, I would let them refoam. The 1st guy I called used to charge 20.
Now for the foams.....I was looking at the Simply Speakers, Springfield, or Parts Express. Just from the ads, I liked Springfields
 
cimchazz1 said:
Thanks CJ for the info on the refoaming. I think the signal generator (in the article I read) helps you know when you are centered by the variation in tone intensity. Of course I will not really understand how it helps until I try one myself. I already tried removing a dust cap on a CV to replace it with a smaller one to match another speaker I had, and that didn't come off very clean, but I used "Goof-Off" adhesive remover. Maybe the acetone of denatured alcohol would have worked better?
Anyhow, I have these 2 speakers now to learn on. Not too worried using them because full rebuild kits are easy to find for 50 bucks, but I would like to keep these original. Heck, if I can find someone local that will do it for $20, I would let them refoam. The 1st guy I called used to charge 20.
Now for the foams.....I was looking at the Simply Speakers, Springfield, or Parts Express. Just from the ads, I liked Springfields
Click to expand...
I like Springfield & Simply speakers
Used both many times...The Speaker exchange is good also but white PVA Glue from their kit, so it just depends on what glue you want to work with
 
Thanks, I will pick one from those 1st 2 (after I make a few more calls to see if I can find anyone experienced around Detroit area who repairs surrounds for $20 each). .
 
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Well, after 7 pages of discussion on 1230's, the yet unsolved mystery is which midrange drivers these came with that will fit in a 3 5/8" baffle hole and have a 4 1/2" spread across screw holes. :idea:
 
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Are you sure on those measurements? I looked at every picture of those speakers, and the mids look like the mids I have in several old cerwins, and they are larger than that. Can you put a picture of the front of your cabinets on here?
 
I just measured a mid from the AT series, 4 1/2 spread. So, we're getting closer! But all the older hed's I've seen have the larger mid with a large round flat metal flange.
 
I was wondering about that too, but what the heck these cabs be??? They have the correct outside measurements.
 

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Cerwin Junki said:
I just measured a mid from the AT series, 4 1/2 spread. So, we're getting closer! But all the older hed's I've seen have the larger mid with a large round flat metal flange.
Click to expand...
Butttttt, do the AT mids fit in the 3 5/8 baffle hole? And do the AT have the "keyhole" cutout for the HO5 tweeter?
 
I'll have the tweeters tomorrow so I will know for sure, The C5G wouldn't go thru the hole because of the triangle under the magnet
 
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