x-over caps on infinity column 2's

[loose ends]

Bill Watkins Sr. designed over 40 woofers. I didn't say they were the dual voice coil woofers. Those were designed for a specific purpose. A cabinet using one woofer. If you read the white paper posts you will see Watkins woofers that are identical to the woofers in the column II's. He even makes mention of what the black coating is. Same black magnets, same black frames, same paper cones. Wouldn't the same effect be obtained using 2 seperate drivers with different, seperate impedance voice coils in a sealed cabinet. This would certainly combat any rolloff and you can extend the range of the woofers. The dual voice coils, and I may, be mistaken, were designed for a cabinet with a single 12" driver with 4 ohm impedance. With a single voice coil trying to get below 40htz the driver would drop below 2 ohms and already being less than effecient speakers this would cook many amplifiers. Bill solved this problem by overlaying one voice coil over the other each using their own inductors and caps.

 

[Dave1027]

I have a pair that I can use some info for while you got yours apart. I need to know how the woofers and tweeters are wired. The tweeters are piezo and the woofers are actually Watkins. I need to know if the bottom woofer is wired out of phase. I used Dayton caps from Parts Express. I find them not as harsh as the Solens. I got these with all the drivers and the crossovers in a cardboard box. Cabinets are great and they even have the glass tops. I know I have one bad tweeter and can't find a replacement so I will have to change something.

Thanks

Column IIs are 3-ways. That means the midrange should be wire out of phase from the woofer and tweeter. If it was a 2-way then you simply wire them out of phase. I don't think the woofers should be out of phase with each other. That would kill the bass.

I am wondering how Infinity got away with putting only 2 caps in a 3-way speaker? Those are classic speakers btw. I love em.

 

[Dave1027]

I'm taking a slightly different approach with the recap of my Column II's.
For the 12.5 cap I'll be using 2- 6.2 uf Dayton caps:
and one Dayton .10 film and foil bypass cap:
For the 3.5 I'll use a Dayton 3.3uf:
and a .22 film & film bypass cap:

I've had great results in the past using a F&F bypass caps.

I commend your effort but if you read those caps with a meter you may find some of these values won't be that close. Certainly not close enough to worry about a .1 uf. You may already be over the value then add another .1 uf for nothing.

 

[jonathanb]

infinity 2 caps

Dave, i swear to god,i have Heresy's and JBL L150a's,and JBL 4411 studio monitors and the infinity's sound better to me than all of them!

 

[Rod G-6000]

I just pulled my drivers and nothing is wired out of phase.
The + (solid red) go to the + of each woofer
The - (red w/blk stripe) to the - of each woofer

The mids are not wired out of phase either.
Remember, the piezo tweets are not part of the crossover network and read "open" on a DMM

Thanks Rod,please post.. because if this guy had my woofers in the wrong spot he may have also mixed up the wires.If they are out of phase that would mean the front woofer would be going out while the lower woofer is going in,kind of equalizing the pressure in the cabinet? weird....missing my top glass so i went to leows and put some 12/12 inch marble floor tiles on top of mine.Still waiting for solens but Commander Cody's greatest hits still sounds good even with old caps.."my pappy said son,youre gonna drive me to drinkin' if you dont stop divin' that hot... ROD.. lincoln"...

 

[goat67]

Bill Watkins Sr. designed over 40 woofers. I didn't say they were the dual voice coil woofers. Those were designed for a specific purpose. A cabinet using one woofer. If you read the white paper posts you will see Watkins woofers that are identical to the woofers in the column II's. He even makes mention of what the black coating is. Same black magnets, same black frames, same paper cones. Wouldn't the same effect be obtained using 2 seperate drivers with different, seperate impedance voice coils in a sealed cabinet. This would certainly combat any rolloff and you can extend the range of the woofers. The dual voice coils, and I may, be mistaken, were designed for a cabinet with a single 12" driver with 4 ohm impedance. With a single voice coil trying to get below 40htz the driver would drop below 2 ohms and already being less than effecient speakers this would cook many amplifiers. Bill solved this problem by overlaying one voice coil over the other each using their own inductors and caps.

We seem to have a disagreement on what is a Watkins woofer I was referring to his dual voice coil design. Reading the specs the Column II's use 2 25 CM drivers and the Quantum series uses a single 30 CM driver so not identical....

Yes I am sure he was working at Infinity at the time of the Column IIs did he design the woofers I have no idea.

Wouldn't the same effect be obtained using 2 seperate drivers with different, seperate impedance voice coils in a sealed cabinet.

I see your point here can someone post a crossover schematic... I would be interested in comparing this to the Quantum schematics.
Something that comes to mind is that this would require that one woofer would be 4 ohms and the other 2 ohms... or maybe 8 ohms and 4 ohms....

BTW I have a pair of the 2000 IIs another speaker from this era.

 

[jonathanb]

column 2's

thanks Rod,guess mine are wired right.anybody interested in a pair of JBL L150A's?
too big for where the column's were, and will be, sitting.

 

[Dave1027]

I just pulled my drivers and nothing is wired out of phase.
The + (solid red) go to the + of each woofer
The - (red w/blk stripe) to the - of each woofer

The mids are not wired out of phase either.
Remember, the piezo tweets are not part of the crossover network and read "open" on a DMM

I see. :scratch2: The piezos get the full range so that means the crossovers are basically 2 ways, woofers and mid. Well, conventional crossover design would normally have those to out of phase. To identify that you would not simply check wire color but would have to analyze the circuit. Then again, having the drivers not in proper phase may not be a big deal and who knows, it may be the way the designers intended.

 

[Rod G-6000]

thanks Rod,guess mine are wired right.anybody interested in a pair of JBL L150A's?

Not a problem.
No interest in the JBL's but you can send the Column II's.

 

[jonathanb]

column 2's

Rod, thanks for taking the time to pull your drivers,and i believe i speak for loose ends also
Jon

 

[loose ends]

Sorry I got sidelined for a while and Jonathanb I appreciate you speaking for me. I too am very thankful for everyone's help. After the refoam and cap replacement I only listened to mine once and that's when I found the bad tweet. I knew you can't test them with a meter so I just switched it and it was bad. So I've let them sit for about six months.

I need to reduce my collection quite a bit in the near future so I want to get these up and running so I can listen to them for a while.

What are you folks using to drive your column II's?

 

[Rod G-6000]

What are you folks using to drive your column II's?

I'm using a Kenwood Modwl Eleven III. 120 wpc.

http://www.audiokarma.org/forums/attachment.php?attachmentid=204426&d=1270580008

 

[Rod G-6000]

After the refoam and cap replacement I only listened to mine once and that's when I found the bad tweet. I knew you can't test them with a meter so I just switched it and it was bad. So I've let them sit for about six months.

You could try this piezo from PE for cheap $ :

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=270-011

You will need to enlarge the mounting hole from 2 1/2 to 3 1/16 though.

 

[loose ends]

Beautiful Kenwood. I have an extra Pioneer sx1010 and a Sansui 9090 that I may use if I wind up keeping these speakers. I also have 2 cheap piezos that I may try. Can't get to them this week but next week for sure.

 

[ohhwell]

I see. :scratch2: The piezos get the full range so that means the crossovers are basically 2 ways, woofers and mid. Well, conventional crossover design would normally have those to out of phase. To identify that you would not simply check wire color but would have to analyze the circuit. Then again, having the drivers not in proper phase may not be a big deal and who knows, it may be the way the designers intended.

I have a later pair of Collum IIs with the recessed fuse holder so can't speak for all but my tweeters have a 3.5uf Cap on them and are therefore crossed over. There is a 2.7 Ohm resister wired after the Pot to allow the Cap to do it's job. This is supported as well by infinity's Spec sheet listing the tweeter crossover point at 5khz. Piezzos can handle full range signal fine but get thant annoying spittle sound if there is no crossover.

The extra black stuff on one woofer would probably be added mass to "Mechanicaly" lower the upper frequency response. That's how they did it with the single woofer on the WLTC. I would imagine that if that is true, they should definately be the bottom firing woofer.

I posted a simple drawing I made of the crossover network a while back I think. I will try to upload my most recent sketch. Pay no attention to the polarity of the speakers as my pair were bastardized when I got them. Also, I don't have a meter that will measure inductance so no idea on the values of the coils on woofers and mids.

http://www.audiokarma.org/forums/attachment.php?attachmentid=234288&d=1286494314

 

[elnaldo]

How is is possible that nothing is out of phase with this xover? Am I missing something?

I'd swear that one driver should be out of phase.... It seems almost the same that my 3 ways xover... 2 coils and 2 caps, and my midrange and tweeter are phase reversed.....

Qb_technical_sheet.pdf

 

[jonathanb]

Big Solen caps

Hi guys,got the Solen caps today and installed them, a 3.3 (replaced 3.5) and a 12 (replaced a 12.5)...bass seems tighter and more clear with the woofers switched and the tweeters are crisp...mids nice and clear.i was suprized at the size of the caps!!! the 12 was the size of a quarter stick of dynamite,and the 3.3 's as big as root beer barrels.
thanks again for everybodys help
Jon

 

[cdfac]

whether or not you have to wire one of the drivers out of phase has to do with the order of the crossover, for one. it also has to do with the response of each driver at the crossover point. i think what infinity did was listen and/or measure and wire the phasing based upon what turned out best, as opposed to basing the decision on strict LRC filter theory.

 

[ohhwell]

How is is possible that nothing is out of phase with this xover? Am I missing something?

I put this disclaimer in my posting you referenced:

"Pay no attention to the polarity of the speakers as my pair were bastardized when I got them."

Someone else pulled the woofers and reported as to the coloring of the wires in relation to the terminals. Some day I will correlate that with my "Diagram"

 

[ohhwell]

Hi guys,got the Solen caps today and installed them, a 3.3 (replaced 3.5) and a 12 (replaced a 12.5)...bass seems tighter and more clear with the woofers switched and the tweeters are crisp...mids nice and clear.i was suprized at the size of the caps!!! the 12 was the size of a quarter stick of dynamite,and the 3.3 's as big as root beer barrels.
thanks again for everybodys help
Jon

Awsome. Thanks for the report on the sound. I am eager to get my pair working again. Even with non-stock woofers and mids, I am thinking they will do admirably on H/T duty.

I have a question though: With all of your stock drivers and piezzo tweeters, what is your impression of the soundstage and imaging on these?