Running Image Dynamics CTX65CS Active (Power Handling)

[StinkPiece]

Greetings!

If you don't feel like reading all of this, I've emphasized my main concerns in bold.

I have been looking for a budget-friendly set of components for a while and have finally pulled the trigger on the CTX65CS system. I saved enough money on them to allow me to start looking at amps a bit earlier than expected.

My current setup is:

Kenwood KIV-700

Polk Audio db651s coaxials in front and rear

Kicker ZX750.1

RE Audio SE12D4

I've started to deaden the doors but I still plan on doing more. I also have some deadened roof flashings cut to seal the big holes in the doors -- I've heard that this goes a long way in improving midbass performance, so I'm looking forward to finishing that project.

I'll try to keep this brief because I have a tendency of rambling on for too long. What I am curious about is, should I decide to buy a four channel amp for the sole purpose of running my front components, how much power should I be looking for per channel to run the system optimally? I haven't completely decided on whether or not it will be worth it in my case but since going active is highly recommended by many people and on many forums, I want to at least give it some thought.

Prior to considering the option, I had looked at some four channel amps that could be bridged to provide enough power at 4 ohms. Most of what I saw was right about 200W RMS x2 at 4 ohms. Unfortunately, my current budget is rather limited so the brands that I've looked at have been Cadence and MB Quart, for the most part. I'm not sure how truthful those ratings are, though.

Would someone new to car audio benefit from going active? I know a thing or two about this stuff but I'd be willing to bet that, as far as knowledge and experience of the active users on here go, I'd be somewhere around the 15th percentile. I can use my ear well enough to get my EQ and crossovers to sound good enough, though they probably don't utilize the true potential of the gear. Having said that, this would be a good opportunity to learn some new tuning techniques. On the other hand, I'm worried that having so many different things to toy around with would leave me constantly tweaking settings, for better or for worse.

One final question on the subject: As far as wiring this setup goes, is using RCA splitters to run the front preamp outs into both front and rear inputs the typical thing to do? I don't want to lose my fader control on the head unit so this seems like the best way to get the signal into all channels. As I think more about this, it is probably a stupid question but I'd feel at ease having an answer from more experienced people. My car (2003 Pontiac Vibe GT) isn't very big but it's open enough that I want to keep the rear fill present enough to make listening enjoyable for those passengers. If I go with a four channel amp just to power the component system, that leaves my rear speakers on head unit power (roughly 22W RMS).

I'll try to wrap this up now. I sincerely apologize if this has been covered before; after a long time digging around for answers, I hadn't seen anyone mention what the power handling of the woofers and tweeters in the CTX65CS set are when going active. I don't want to buy an amp that has way more power than needed but, on the same token, I don't want to waste money on an amp that doesn't cut it. I'm open to suggestions on which amps to consider. I'd like to keep the cost under $200-$250, if at all possible (and I'm completely fine with buying used). I'll be keeping an eye on the classifieds but having a rough idea of what wattage to look for will be a great help!

Thanks a lot, guys!

Best,

Justin

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[Gregulate 10+ year member]

I'm kind of new to this stuff, myself, but as far as amps, check Ebay. I got a 4 ch 60wpc amp for

As for how much to power them, I believe that's subjective. You probably won't run them rated at their specified RMS since you don't want to run your amps at full gain, so I'd say somewhere between like 50 - 75 RMS should work. I have some power hungry HT speakers at my house that call for up to 250 watts and I give them a max of 60. I think it all depends on how loud you get.

 

[Why So Cereal? 5,000+ posts]

Power to run per channel...I'd say look for about 50rms per channel maybe 75 but I doubt you'll tell a difference between the 2 audibly. Its reallly your choice as to how much power you run though. I know my Pioneer TS D1720C set has been known to run actively with 150w to each channel. I run 125 to the midbasses alone, if those IDs are built as well as i keep hearing, then I think they'll take a good bit of power as long as youre not clipping em.

As far as being new and going active....why not?? experience is life's best teacher. It gives you a chance to really learn your system and how to make it sound the best, but of course it will be more work than simply dropping the speakers in and riding. I say go for it! keep in mind though, that unless youre running a 6 channel amp, you will only be able to amp the front stage since you'll need a channel per mid and one per tweet. this may be what youre going for though.

 

[keep_hope_alive Premium Member]

Sundown SAX 100.4D amps give you flexible active crossovers built-in, and decent power. tweeters need much less power than woofers simply due to the difference in sensitivity and the sensitivity of our ears.

yes, a Y-adapter is fine for feeding all four inputs from two front outputs.

 

[StinkPiece]

Thanks for the suggestions, guys. The more I think about it, the more I'm interested in going active. Had I known that I would end up going this route, I probably would have given more consideration to buying the woofers and tweeters separately. It's no big deal, though; I've read enough positive things about the ID set that I'm still excited about the purchase.

I don't plan on amping my rear speakers yet so having a 4 channel amp dedicated to the front stage isn't a major setback. I'm happy with my Kicker sub amp and my head unit drives the Polk Audios that I have in there right now pretty well. The thought had crossed my mind to get a four channel amp and run two channels for the fronts (passive crossover) and bridge the other two as a replacement sub amp. Having some motivation to go active has convinced me otherwise, which is nice, since the ZX750.1 goes well with my RE Audio 12" sub.

I'll definitely check out the Sundown amp that keep_hope_alive mentioned. It looks like it may be out of my initial budget but I won't rule it out, even if it means waiting a few extra weeks. I suppose there's no use in skimping on an amp, at this point, since it looks like I'll be using it as the crossover.

---

Does anyone know of a good reference for how to properly setup a power distribution block? I wired my ZX750.1 under my passenger seat with a 4 gauge kit so I am probably going to pull that out and relocate it to the trunk with whatever amp I add to the setup. I'd like to use 2 gauge wire (or should I go 0/1?) but the old wiring can still be useful for connecting the sub to the distribution block. I've done some browsing around the web and haven't seen anything that puts my mind at ease (particularly when it comes to placing the in-line fuses). I'm comfortable with doing the install but I would rather not get electrocuted or short out my system in the process. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

A recommendation for a good block would be very much appreciated, as well. I'd technically only need 2 outputs since I don't want to push my alternator too hard with another amp. It's rated for 80 amps, I believe. I'm not sure if having three amps pulling from it would pose a problem but I'll see how having two amps in my system works out. I doubt that I'll feel the need to amp the rears, anyway.

I appreciate all of the help you guys have been kind enough to offer. It's making my decisions easier and I feel confident that I'll be happy with whatever setup I end up with. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[groundpound4200 5,000+ posts]

I run my Image Dynamics OEMs (which are pretty similar) off a Sundown SAX 125.2 and they handle it just fine. I'm actually looking into their 2 ohm CX2 mids to run more power to the mids. Going active is not that hard and once you figure out what the speakers like for frequency response in the car it's a breeze.

 

[DukeNut 10+ year member]

be sure to do the big 3 wire upgrade also

 

[zako 10+ year member]

Do you have T/S parameters for the mids? One way to find out what's the limit of their mechanical power handling, is load the parameters in WinISD and start a project. (There is no option for IB, I usually just specify a 1.5 to 2cu ft sealed box to approximate a door, should be good enough IMO). In the filter section apply a high pass filter you need to use, e.g. 3rd order high pass filter at 80Hz. Now switch to cone excursion graph and start adding wattage in the signal tab below until the maximum cone excursion of the driver reaches the one way xmax of the driver in milometers (if specs give peak to peak xmax number, divide it by two). The number in the signal tab is the maximum amount of power that the speaker will take while still playing in it's "SQ range". There is no point to have more power, because the excursion beyond that number will produce highly distorted sound. You will be surprised how little power most drivers need to get there.. a lot will take 60-80watts tops under this criteria. However, note than most amps are rated at 14.4V these days which is the voltage that they probably won't see under normal car operations.. so if you need your amp to be able to run 70-80watts of power under number conditions, an amplifier rated for 100watts RMS at 14.4V would be approximately the upper limit of you need.

 

[zako 10+ year member]

as wiring this setup goes, is using RCA splitters to run the front preamp outs into both front and rear inputs the typical thing to do? I don't want to lose my fader control on the head unit so this seems like the best way to get the signal into all channels. As I think more about this, it is probably a stupid question but I'd feel at ease having an answer from more experienced people. My car (2003 Pontiac Vibe GT) isn't very big but it's open enough that I want to keep the rear fill present enough to make listening enjoyable for those passengers. If I go with a four channel amp just to power the component system, that leaves my rear speakers on head unit power (roughly 22W RMS).

I don't know what's the best way to do it, but Y splitter should be fine. I personally do not use a Y splitter. So my front pre-amp connects to the amplifier and then to the tweeters (with a capacitor inline to act as a crossover). My rear pre-amp connects to the other 2 channels on the same amplifier and then those channels power the woofers. The reason I did it this way so I were able to apply time alignment from my Kenwood head unit to tweeters and woofers independently from each other. This was one of the two motivations for me two switch to active (the other was to match levels better). Being able to time align each driver individually made a pretty big difference in SQ compared to the results with TA applied to passive component sets, and I haven't even tried to more "formal" ways of tuning TA yet (using pink noise, etc).

So my "fader control" is now just a level control between tweeters and woofers, but I prefer to leave it at middle position, and tune amplifier gains instead. This means that I can't adjust my rear speaker volume from head unit, but that's not a big loss because I have run out of amp channels after installing front speakers and sub..