Cerwin Vega speaker help needed

[desertrat748]

Just found the VSW12 rebuild kit, it is a 4-ohm w/2" 2-layer voice coil. I think the L121-4 is 8 ohm w/1.5" 4-layer voice coil, very different performance I would think

I don’t know but I checked dc resistance on both of them and I matched them. Heck I am going to pull the other one out and see. I think you are going to be okay with the 8 ohm L121-4. Whatever you get, match them as a pair.

 

[cimchazz1]

Hey, now we're havin fun!!!! I think that's most of the restoration instructions, or a darn good start. That's a lot of new info posted on late '70's/early 80's HED U123, U321, and 1230, more than I've been able to find before, thanks DR!!! I actually have an L121-4 I got from Skywatcher, but it has ribs in the cone, so hard to find a match. I might just end up with one ribbed and one not. Those cones are hard to find I think

 

[cimchazz1]

Thanks a lot for checking the wire colors, you're right, never thought to followcup from the pots. BTW, the pots sometimes have date codes stamped on the back too, just like in guitars. I'm using my phone now, so can't really tell what your pots say, I'll look later on. It's 2:30am here in MI.

 

[desertrat748]

I don’t know but I checked dc resistance on both of them and I matched them. Heck I am going to pull the other one out and see. I think you are going to be okay with the 8 ohm L121-4. Whatever you get, match them as a pair.

I see a L 121-4 being sold and dc resistance is shown at 5.1 ohms.

 

[Skywatcher]

View attachment 1519344

One of the woofers. Looks like a replacement maybe? Vsw-12 looks like August 17 78 or 79? Maybe? Cabinet has a clear date of 1-31-1980. The tag on the back used to say 1980 before it faded. I’m thinking maybe the other one was stamped December ‘79 but I can’t remember that clearly anymore and it has fallen off a long time ago.

The VSW-12 has a 2"voice coil and can handle a lot more power. I might have a couple of bare frames around here. I'll have a look.

 

[Skywatcher]

Hey, now we're havin fun!!!! I think that's most of the restoration instructions, or a darn good start. That's a lot of new info posted on late '70's/early 80's HED U123, U321, and 1230, more than I've been able to find before, thanks DR!!! I actually have an L121-4 I got from Skywatcher, but it has ribs in the cone, so hard to find a match. I might just end up with one ribbed and one not. Those cones are hard to find I think

Look what I found in my "stash". I have one complete VSW-12 that needs rebuilt, dated March 09 1981). The spider is soft and sagging. But I can replace just the spider and surround, and that water stain is no big deal. I can lightly coat it to re-bind the fibers, and stain it black keeping the original "sound". And since it is original, I can find a very close match to the cone weight and composition for the other frame. It looks like a non-pressed pulp cone. Take a look at the surround. The top layer of foam is gone (I peeled it off) and the 2nd layer is a very tough type of material (I can't tear it), much like a cloth, but doesn't look like cloth. The bad part is I can no longer find that type of surround but will use the modern dual-layer all foam surrounds. Plus I can match the voice coil for the other bare VSW-12 frame (Dated April 12 1996). These have an extended pole for longer excursion too. PM me if you might be interested in them. And we can trade back the L121-4 towards these.

 

[7whales7]

If you want to "clean up the sound " you may want to consider changing the Capacitors in the crossovers, they have some years on them.

 

[desertrat748]

Now we are having fun! Thanks for the clarification SkyWatcher. I’m getting forgetful. Clearly the voice coil is larger on the VSW.

Cim, keep up the good work and now that you have your tweeters on the way, match up a pair of woofers! You’re going to be enjoying the music soon!

PS. What are the midranges in your cabinets ??

 

[Skywatcher]

If you want to "clean up the sound " you may want to consider changing the Capacitors in the crossovers, they have some years on them.

These have film capacitors (10%), so they don't degrade the way electrolytic capacitors do. Better quality (5% or 2%) film caps might make a small improvement though. And they're not all that expensive for, say Clarity caps. The shape and physical size is what you need to watch for. The way the crossovers are designed, you'll have to go the "make it fit" route. so they fit back through the cutout. Soldering while in the cabinet can be a real pain too.

 

[desertrat748]

These have film capacitors (10%), so they don't degrade the way electrolytic capacitors do. Better quality (5% or 2%) film caps might make a small improvement though. And they're not all that expensive for, say Clarity caps. The shape and physical size is what you need to watch for. The way the crossovers are designed, you'll have to go the "make it fit" route. so they fit back through the cutout. Soldering while in the cabinet can be a real pain too.

^ This. I haven’t had any problem or loss of high end with mine. Nor my younger brother who liked mine so much he bought a pair.

I don’t think it’s worth the time or expense if, if they are producing a decent high end. If one is clearly not the same as the other; time to check it out. Otherwise, let a sleeping dog be.

 

[Skywatcher]

^ This. I haven’t had any problem or loss of high end with mine. Nor my younger brother who liked mine so much he bought a pair.

I don’t think it’s worth the time or expense if, if they are producing a decent high end. If one is clearly not the same as the other; time to check it out. Otherwise, let a sleeping dog be.

Agreed! My UT12R also have the stock film caps and they sound just fine. The only thing I did to them was change the tweeters out with some old Utah Alnico (Heppner) metal horn tweets, and put some Bob Crites titanium diaphragms in them. Now when I "crank it up", the harshness is gone and the highs sing so smoothly with no fatigue. So obviously the original film caps are performing perfectly fine. My 29P speakers will be getting the same treatment as soon as I find another set of tweets. Although they sound good now, they are a little harsh cranked up. They too have the stock film caps. The only "weakness" in the chain are those tweeter breakers. They do go bad on occasion, though usually from repeated "abuse".

 

[cimchazz1]

Look what I found in my "stash". I have one complete VSW-12 that needs rebuilt, dated March 09 1981). The spider is soft and sagging. But I can replace just the spider and surround, and that water stain is no big deal. I can lightly coat it to re-bind the fibers, and stain it black keeping the original "sound". And since it is original, I can find a very close match to the cone weight and composition for the other frame. It looks like a non-pressed pulp cone. Take a look at the surround. The top layer of foam is gone (I peeled it off) and the 2nd layer is a very tough type of material (I can't tear it), much like a cloth, but doesn't look like cloth. The bad part is I can no longer find that type of surround but will use the modern dual-layer all foam surrounds. Plus I can match the voice coil for the other bare VSW-12 frame (Dated April 12 1996). These have an extended pole for longer excursion too. PM me if you might be interested in them. And we can trade back the L121-4 towards these.

Boy, those have seen a few good partys I bet. I'll PM you. Thanks

 

[cimchazz1]

If you want to "clean up the sound " you may want to consider changing the Capacitors in the crossovers, they have some years on them.

If I DO need a cap or two, any suggestions for brand/type/value? I'll check them first, but pretty easy to just upgrade., too. I thought they actually looked to be in good condition. I did hook up one of the Radio Shack piezo tweeters to my Model 26 cab to try it and a thought a swarm of locusts were attacking!!

 

[cimchazz1]

^ This. I haven’t had any problem or loss of high end with mine. Nor my younger brother who liked mine so much he bought a pair.

I don’t think it’s worth the time or expense if, if they are producing a decent high end. If one is clearly not the same as the other; time to check it out. Otherwise, let a sleeping dog be.

There won't be any sleeping dogs around here after I get these going!

 

[cimchazz1]

Now we are having fun! Thanks for the clarification SkyWatcher. I’m getting forgetful. Clearly the voice coil is larger on the VSW.

Cim, keep up the good work and now that you have your tweeters on the way, match up a pair of woofers! You’re going to be enjoying the music soon!

PS. What are the midranges in your cabinets ??

BTW, (trying to catch up here on responses), my present mids are (of course) Optimus, (like everything else in these cabs). They are #40-1030, 40 wattRMS, 320-5000Hz freq resp, 88db sensitivity, 1" VC, 120oz. magnet, 8ohm.. Might be ok, actually, until I find a good price on the correct mids.

 

[cimchazz1]

View attachment 1519360

Can you take a pic of the back of the speaker box where the wire connects? Basically the back of the cross over?

My cross over.

Here's the back of mine....... (with "original" dust)

 

[cimchazz1]

Agreed! My UT12R also have the stock film caps and they sound just fine. The only thing I did to them was change the tweeters out with some old Utah Alnico (Heppner) metal horn tweets, and put some Bob Crites titanium diaphragms in them. Now when I "crank it up", the harshness is gone and the highs sing so smoothly with no fatigue. So obviously the original film caps are performing perfectly fine. My 29P speakers will be getting the same treatment as soon as I find another set of tweets. Although they sound good now, they are a little harsh cranked up. They too have the stock film caps. The only "weakness" in the chain are those tweeter breakers. They do go bad on occasion, though usually from repeated "abuse".

I think I'm gonna have to try a set of those Crites diaphragms soon!!! I'll bet that makes a HUGE difference.

 

[desertrat748]

Here's the back of mine....... (with "original" dust)

Look exactly like mine save the 123O on there. Maybe this was the model they sold on military bases? I don't think your mids (optimus) will be correct for the CVs. I guess give them a try first?

 

[cimchazz1]

DR, I agree. And these could be from a base possibly.

 

[cimchazz1]

So I measured across the screw holes on the woofer, I get about 4 5/8" (maybe 4 1/2?). Does this match the speakers you guys have? I don't want to get the wrong speakers, wondering if they are the 6" or something else?