custom center from polk parts question

selkec

I hope this is not a stupid question but I got the idea after running into polk parts on ebay from the rti12. I was thinking how cool it would be to build a massave center with the drivers to better match the rtia9's. I think the csia6 is just too small. Im in the bigger the better camp.

Does this sound stupid. Has anyone done it. The parts kit on ebay is enough drivers for 2 towers so I was thinking lets put in four 7" for bass, two of the mids and the tweeter. This would be massave I know but I like massave.

What are your thoughts?

ROHfan

Not a stupid question at all. In fact, I have some Monitor 10s that I had a crazy idea about taking out the woofers and tweeters from one cabinet and installing them into a center channel cabinet so it could match my SDA 2As when watching movies. Doing it this way I wouldn't have to worry about crossover components since it's already done and the drivers would be the same, I think. I'd just have to play with sealing and insulating the cabinet.

Different crossovers and drivers would yield a sound that wouldn't match your rti's, IMO, and that's the most important aspect of choosing a center channel. Let us know how you make out if you go for it.

falconcry72

The best option is to just use another RTiA9, upright, as a center. It's always best to use a 3rd identical tower, but often that's not possible because of space constraints.

I'd say your second best option is to run dual CSiA6's. One above and one below the screen.

If you're set on making something custom, be sure you use the same quantity of the same types of drivers, the same crossovers, and the same internal cabinet volume of an existing speaker... otherwise you're just guessing.

selkec

Yeah. I dont have space to get another tower. I could lay it on its side but then the tweeter is to one side. I thought about dual csia6's but dont want to go that route. I would really like a true matching center with same drivers. The csia6 needs a bigger brother with the 7" bass drivers in it

I sold my csia6 in thoughts of changing over to the LS6 speakers from av123/gr research and now have the x-voce flipped over to seal up the open baffle and it actually blends just fine. I dont even notice it not being matching at all. I just want my speakers to match is only reason I wanted to try something different.

falconcry72

selkec wrote: »

Yeah. I dont have space to get another tower. I could lay it on its side but then the tweeter is to one side. I thought about dual csia6's but dont want to go that route. I would really like a true matching center with same drivers. The csia6 needs a bigger brother with the 7" bass drivers in it

I sold my csia6 in thoughts of changing over to the LS6 speakers from av123/gr research and now have the x-voce flipped over to seal up the open baffle and it actually blends just fine. I dont even notice it not being matching at all. I just want my speakers to match is only reason I wanted to try something different.

Ok have it your way. Here's how you do it:

- buy a 3rd a9
- remove the drivers, guts, and front face
- create a new front face for new component placement (tweeter in middle, flanked by mids, 2 subs on one side, a sub and the port on the other side).
- reassemble components

This way, you'd be keeping the exact internal volume, crossover specs, and driver compliments that the polk engineers worked so hard to achieve, you'd just be rearranging them for a horizontal orientation.

You could also do it with an a7 if the a9 is too big for your space.

selkec

Thats actually a good idea. I think I would do the rtia7 so the subs would not be an odd number

falconcry72

I wouldn't worry about the subs being uneven, that port puts out a good amount of bass, plus bass is hard to localized anyway. With the a7, either the midrange driver or tweeter would have to be off center, which would be more noticeable than uneven subs. Plus the midrange on the a7 is different. Go a9 if you have the space, but either one would be sweet.

Keep us posted with lots of pics if you do this!

Toolfan66

selkec wrote: »

Thats actually a good idea. I think I would do the rtia7 so the subs would not be an odd number

I have wanted to do that for some time now..

VR3

Hmm...

I am pretty sure you would have to do some crossover adjustments to compensate for the horizontal versus vertical orientation. When you have two drivers side by side doing the same frequency there will be issues.

Toolfan66

VR3 wrote: »

Hmm...

I am pretty sure you would have to do some crossover adjustments to compensate for the horizontal versus vertical orientation. When you have two drivers side by side doing the same frequency there will be issues.

Maybe, but I doubt it would be very noticeable..

B Run

I'm the last person who knows how to pull off something like that, but if you (or anyone) figured it out or made one i'd be first in line to buy it!

cincycat13

It's a shame pix didnt make it thru the forum upgrade...one memeber built a center from an RTA15

http://www.polkaudio.com/forums/showthread.php?100007-RTA-15tl-or-crossover-and-drivers&highlight=rta15+center

there is a nice link to a diy center project in the thread.

http://www.hometheaterhifi.com/volume_8_3/diy-13-audax-center-channel-speaker-9-2001.html

selkec

VR3 wrote: »

Hmm...

I am pretty sure you would have to do some crossover adjustments to compensate for the horizontal versus vertical orientation. When you have two drivers side by side doing the same frequency there will be issues.

What speakers would be side by side if doing only 2 sub drivers out of the a7? Polk needs to make a bigger center. Klipsch, paradigm and many companies do it. For what its worth my x-voce is in another league than the csia6 I sold to get it. I just want a matching center with some punch to it. I think the a6 is lacking in the lower end

VR3

I was under the impression a A9 was being used

michael1947

Wouldn't 2 csi 6's or a6's work just as well as one big home made box...and the cross overs and interior volume is already calculated. If you ran 2 centers would you split the speaker wire from the amp. I am doing this now and trying a pair of modded lsi 7's as a center and it sounds pretty nice but will likely go back to 2 centers of some kind or another. I may even go back to some old Klipsch centers, I have a pair and I don't have their model numbers they are a part of my old KG system with 1 horn and 2 5.25's each and I'm considering them because of their 93db efficiency where in my simple thinking I figure I will get more center volume with the same level settings. I'm using modded SDA-SRS's as fronts and I always seem to be monkeying around with centers....:redface:

selkec

michael1947 wrote: »

Wouldn't 2 csi 6's or a6's work just as well as one big home made box...and the cross overs and interior volume is already calculated. If you ran 2 centers would you split the speaker wire from the amp. I am doing this now and trying a pair of modded lsi 7's as a center and it sounds pretty nice but will likely go back to 2 centers of some kind or another. I may even go back to some old Klipsch centers, I have a pair and I don't have their model numbers they are a part of my old KG system with 1 horn and 2 5.25's each and I'm considering them because of their 93db efficiency where in my simple thinking I figure I will get more center volume with the same level settings. I'm using modded SDA-SRS's as fronts and I always seem to be monkeying around with centers....:redface:

If you split the speaker wire from the amp then that is wiring it parallel and the amp would see a 4 ohm load instead. I also thought about doing dual a6's but I would use 2 seperate channels off of an amp. I hear people saying using 2 centers side by side would cause comb filtering. I know nothing about combfiltering though.

But it still comes back to not loudness but the lack of punch I find in the a6. My x-voce has very much punch. I want this sound in a polk box. SO polk needs to make a bigger center with bigger or more drivers

teamjhertz

I would stay away from the kit on eBay. It appears that it uses a different tweeter and another brand crossover than the RTi12.

On another note. Could you give some more impressions on the X-Voce vs the CSiA6? I have a CSi5 and was looking to build the
x-Voce and either the X-statik or X-MTM from the leftover AV123 stock that GR Research has.

Thanks

selkec

teamjhertz wrote: »

I would stay away from the kit on eBay. It appears that it uses a different tweeter and another brand crossover than the RTi12.

On another note. Could you give some more impressions on the X-Voce vs the CSiA6? I have a CSi5 and was looking to build the
x-Voce and either the X-statik or X-MTM from the leftover AV123 stock that GR Research has.



Thanks

The x-voce seems to have a big soundstage. There is less sibilence. you know the ssssss sound. That drives me crazy. It is clean sounding and had so much more punch/impact. It has so much more punch you can feel gun shots from movies in your chest. I cant really describe it, but it was a huge step up from the csia6.

teamjhertz

Thanks that sounds like exactly what I am looking for.

I was thinking about your idea and actually called Polk to see if they had components in stock and they did. The prices were kind of high. My idea was the following: RTi12 tweeter/mids/crossover and a pair of the RTi10 woofers. This way there would be a even number of woofers and the cabinet size would not have to be quite as large as a RTi12.