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Replacement woofer suggestions for Cerwin Vega U 123 ?

PR Audio said:
The tweeter is nice, but only 91dB in a high efficiency speaker, it should be at least 93dB. But, since the speaker has L-Pads for Tweeter and Mid, you might get away with using the ones you have. Is there a sealed box inside the enclosure for the mid? If so, what is the volume for the mid enclosure?

If the mid has no independent enclosure, you could use the Pioneer mid and behind it put a PVC 40 DWV 8" Dia. Cap, as to make an enclosure for the mid. Attach it to the inside of the cabinet with Liquid Nails LN-2000 or other Heavy Duty construction adhesive. Line the inside and outside of the cap with damping material. Or use one of these foam baffles, and make it easy. You will only loose 0.1 cu.ft. of space inside the speaker enclosure, which is not a big deal in this case.
Click to expand...
PR , thanks much for helping me out with this . Btw, the mid speaker I have is not pioneer, it's a 5-1/4" Alesis linked below . These are the mids and tweets I have .
Pioneer 3/4" cloth tweeter 2000hz-20k http://www.parts-express.com/pioneer-add64-56f-3-4-cloth-dome-tweeter--270-045
Alesis 5-1/4 poly cone 73hz-4500hz http://www.parts-express.com/alesis-5-1-4-poly-cone-woofer--299-160
And I also have 4 of these, (new) , they seem good but unfortunately they are 4 ohm http://www.parts-express.com/alesis-1-shielded-soft-dome-tweeter--279-140

Looking at the U123 Spec , the crossover points are 1250hz and 6500hz , and the 5-1/4" Alesis mids I've got only spec up to 4500hz , I would have a low spot from 4500hz to 6500hz ???
Should I try to change to the crossover point down to 4K ? (The pioneer tweeter I have specs from 2k-20k) Looks like a 7uF , a 1/5 uF and another cap underneath that . Any help is appreciated
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U123_crossover.jpg
 
I though you had a pair of PIO 4.5" Full Range drivers...Anyways, if the lowest XO freq. is 1250 Hz you don't need a separate enclosure for the mid, as it is only working from 1250 Hz to 6500 Hz. As you mentioned the Alesis only goes up to 4500 Hz, and we don't know how clean it is up there, as there is no graphs. Since your tweeter has the ability (doesn't mean it will be clean there) to play as low as 2000 Hz, and your Alesis mid probably starts to break up at around 3800 Hz, I would make my high XO point 3500 Hz; there is a "safety area" for the mid to tweeter XO freq.

This horn tweeter by Pyle and this more economic tweeter PE private label, are closer to what the CV U-123 had installed at the factory. This 5" Pyle Midbass Driver would be a good replacement for the original ones.

Looking at the way the enclosure is built, and having the components for a 2-Way 1250 Hz XO and L-Pads. Have you given any thought to building a 2-Way horn speaker? An E-Wave? I'm no expert on E-Waves, lots of people here are. You might get away with using this compression driver with this horn lens. Leave the XO freq. at 1250 Hz, and use the L-Pad to bring down the horn SPL to match the woofer. You could use this Pyle PDS221 Compression Driver, which can play down to 800 Hz, with a Dayton H6512 Horn or less expensive PRV WG23-25, depends on the minimum opening size you can do.
 
PR Audio said:
I though you had a pair of PIO 4.5" Full Range drivers...Anyways, if the lowest XO freq. is 1250 Hz you don't need a separate enclosure for the mid, as it is only working from 1250 Hz to 6500 Hz. As you mentioned the Alesis only goes up to 4500 Hz, and we don't know how clean it is up there, as there is no graphs. Since your tweeter has the ability (doesn't mean it will be clean there) to play as low as 2000 Hz, and your Alesis mid probably starts to break up at around 3800 Hz, I would make my high XO point 3500 Hz; there is a "safety area" for the mid to tweeter XO freq.

This horn tweeter by Pyle and this more economic tweeter PE private label, are closer to what the CV U-123 had installed at the factory. This 5" Pyle Midbass Driver would be a good replacement for the original ones.

Looking at the way the enclosure is built, and having the components for a 2-Way 1250 Hz XO and L-Pads. Have you given any thought to building a 2-Way horn speaker? An E-Wave? I'm no expert on E-Waves, lots of people here are. You might get away with using this compression driver with this horn lens. Leave the XO freq. at 1250 Hz, and use the L-Pad to bring down the horn SPL to match the woofer. You could use this Pyle PDS221 Compression Driver, which can play down to 800 Hz, with a Dayton H6512 Horn or less expensive PRV WG23-25, depends on the minimum opening size you can do.
Click to expand...
yes I have the 4-1/2" pioneers also. i'd just have to make a spacer adapter, they are a little too small for the opening. I noticed in another thread you suggested a few other 5-1/4" mids...if you think the ones i have aren't very good then what do you think about other 5-1/4" mids. I'm not concerned with keeping these original, just want to get them to sound good for out in my shop. Thanks again sir ! I appreciate it.
 
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There is plenty of 5-1/4" mids for your application. Depends on what you want to do. Seems to me you want to repurpose the U123's and keep their same layout while using the same enclosure and crossover. If that is what you want, none of the components you have at hand, except for maybe the tweeters will work properly. Already mentioned which horn tweeters are a good alternative and not expensive, as for 5-1/4" or 5" mid you could go with the Pyle I mentioned or one of the following:

+ Tymphany FSL-0512R01-08

+ FaitalPro 5FE100

+ Goldwood GM65/8
 
PR Audio said:
There is plenty of 5-1/4" mids for your application. Depends on what you want to do. Seems to me you want to repurpose the U123's and keep their same layout while using the same enclosure and crossover. If that is what you want, none of the components you have at hand, except for maybe the tweeters will work properly.
Click to expand...
I have a pair of Dayton Audio ST305-8 12" at hand, the ones you recommended... They won't work ??? ...lol Thanks anyway for the help.
 
Unless i'm down there vvv playing, mixing, recording , I have nowhere else in the house with a decent system to just enjoy music...haven't had a listening space in a long time. I'm using an RME UFX at 24/48 , Seventh Circle Audio pres , N72 neve clones , A12 API c84 and J99 John Hardy pre's. But I spend my off time out in the shop working on my dirt bikes, wood working and TIG welding, it's 25'x25'x10'ceilings ...I've recently put a system out there from some stuff given to me , budget 301 bose an old Fisher and now a Yaqin MS-30L I just bought. I found these U123's and they seemed interesting to tinker with.
I got the Daytons you recommended https://www.parts-express.com/dayton-audio-st305-8-12-series-ii-woofer--295-120
Yes, I like to tinker with things, repurpose. I know basic electronics from my time in the Army , I don't rebuild/build speakers or crossovers ...so i'm on here asking ...because I'm
interested, and this seemed like a good forum .
Also found a pair of these crosovers , they say EMB CX-10 , Low: 20hz-500hz , Mid: 500hz-3. 5khz High: 4. 5khz-20khz 600 watts rms .
More useless stuff ?
Thanks again .
StudioYamahas.jpg
 
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I believe you can repurpose the existing crossovers. The Yaqin is a nice amp, don't go into the tube forum, next thing you'll know is that you are following instructions on how to make it better. The U123 will match nicely with the Yaqin amp. Have you decided what to do with the mids? Nice home studio.
 
Decided i'm just gonna try the Pyle mids , and also try each of what i've got, I've got a few different 5-1/4" mids here (ordered a set of those Pyle mids you mentioned)
they seem like they'd be the best fit .I guess i'll have to try each of them and see how it sounds. They are a little small for the 5" opening , I can fab something though.
I'm going to try the Alesis M1 4ohm tweeters I've got, they were supposed to be pretty good ...i'll also try the pioneer tweeters I have .
I've got some 4 ohm 100w resistors to series with the 4 ohm Alesis M1 tweets . They M1's all read 7.9-8.1 ohm resistance on a Fluke 12 , I can't measure their impedance.
The Dayton 12's arrived https://www.parts-express.com/dayton-audio-st305-8-12-series-ii-woofer--295-120

Alesis Reference monitor tweeters http://www.parts-express.com/alesis-1-shielded-soft-dome-tweeter--279-140
Pioneer tweeters http://www.parts-express.com/pioneer-add64-56f-3-4-cloth-dome-tweeter--270-045

Pyle Mids http://www.parts-express.com/pyle-pdmr5-5-sealed-back-midrange-speaker-driver--292-200
Alesis 5-1/4 mids I have PE# 299-160
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U123_cabs.jpg
 
The Alesis Tweeters along with the Pyle Mid and Dayton Woofer should work fine in the enclosure and with the existing XO.
 
All done. The Dayton 12's sound very good ! My MS-30L drives these things to concert levels ...and still clear (enough for out in the shop)
IMG_20160405_205139.jpg
 
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The Pyle's are still in there . One of the Pioneer tweeters in the pic above blew . I decided to try the Alesis tweeters with a 4 ohm resistor in series. They are neither too loud or too attenuated, they sound just about right with the 4 ohm resistor . I Haven't done anything with the crossover yet . I spent all Saturday prepping for a race and raced sunday.
Alesis Reference monitor tweeters http://www.parts-express.com/alesis-1-shielded-soft-dome-tweeter--279-140

My cheap phone distorts very easy------>

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CerwinAlesisTweets.jpg
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AlesTweets.jpg
 
Nice, enjoy them! If they sound right with the XO as is, you can tinker with it when there is time for that. What are you racing? Guess Moto X from some pics and the video.

BTW, as you, I'm fully aware that a video will never tell the whole truth about how a sound system sound's, but gives you an idea. Lots of detail, very nice highs, balanced, and apparently very spacious sound.
 
Been reading this thread, and PRAudio gave you some excellent advice along the way. He invested a lot of time in checking proper components for you, and I'll bet the end result is nice. One question for PRA. Would he not be better served by crossing the woofer at a lower frequency? Say, 500Hz or thereabout? My own experience (for it's worth) has led me to conclude that crossing so close to the mid range frequencies can cause the woof to become a bit nasal and honky. 'Course, these are shop speakers, so listening is not critical. Curious to what you think.

GeeDeeEmm
 
gdmoore28 said:
Would he not be better served by crossing the woofer at a lower frequency? Say, 500Hz or thereabout? My own experience (for it's worth) has led me to conclude that crossing so close to the mid range frequencies can cause the woof to become a bit nasal and honky.
Click to expand...

In my experience that happens when the crossover is providing insufficient attenuation as the driver naturally gains as frequency climbs as does it's impedance. Being 12" drivers, these will probably be 6dB up near 2kHz and with 2" coils they are likely 12 or 16 ohms at that point too.
 
I race in the Enduros and HareScramble series. I got 2nd in class last Sunday. Alot of carnage with all the recent rain ! The mids are closed back. They were a little too small for the opening so I cut the rings off the stock mids that were ripped and shot, then i welded them onto the new mids. Theres alot of reflective surfaces in the shop...not the best for sound but hey ...I think I need to build a better Crossover .
 
I'm amazed that that can be done without setting light to the paper gasket! It might be worth running some silicon sealant around the inside of the joint, to prevent any 'chuffing'.
 
J1mbo said:
I'm amazed that that can be done without setting light to the paper gasket! It might be worth running some silicon sealant around the inside of the joint, to prevent any 'chuffing'.
Click to expand...
;-) no , it doesn't even touch the paper. If you set the amperage right and get a very sharp tungsten in there real tight , it's welded before any heat spreads. I'm using 0.030" filler wire and blasting it very fast to control heat input. And the aluminum blocks it's resting on are there to wick away heat fast. I use Alum or copper backing wherever i need to control or confine the heat input. The little smoke u see is the paint inside the rim. U can see im immediately touching it to rotate it. I ran some sealant on the backside seam . Definitely a Frankenstein speaker ...haha
 
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