Tantrum 600.4 & RSDc comp question

dako · Post by **dako** » Sun Sep 28, 2008 7:17 am

Hey Guys,

I'm torn between using a Tantrum 500.2 or a 600.4 on my front stage setup. The 500.2 is a no-brainer as far as setup goes, but I'm having a bit of trouble trying to figure out how I would bridge the 600.4 so I get a Left Channel and Right Channel. This is possible, right? I'm hoping to take advantage of getting 300 x 2 out of it, but I'm not quite sure how to route the RCA cables to it.

If I send the RCAs to the front channel, and set the Rear Channel input select to "F", this should work, right? My big question is, does the amp separate the stereo signal between the front and rear channels? (i.e. front channel would be left, rear channel would be right...) Or will I have to set up my RCA cables in a specific manner? (i.e. L channel of RCA going to front channel, R channel of RCA going to rear channel).

Any help would be greatly appreciated. I haven't mounted this thing up on my newly built amp rack yet, and I'd definitely like to get everything sorted out (that would be a first!) before I go drilling holes and what-not.

dako · Post by **dako** » Sun Sep 28, 2008 10:25 am

The more I think about it, I guess RCA splitters would be the way to go? Front would be Left Channel coming from the L RCA w/splitter, Rear would be Right Channel coming from the R RCA w/splitter. The amp could then be bridged for each channel. Am I taking crazy pills, or is this right?

Post by **smgreen20** » Sun Sep 28, 2008 2:15 pm

I don't know a whole lot about the Tantrum line, but if you were to bridge chs 1/2 together and chs 3/4 , then 1/2 would be the left and 3/4 would be the right.

All you would need to do is run the L/R RCAs to the front input. Rears needn't be used. Set the amp, if it has a mode select type switch, to 2 ch bridged operation.

Me-262 · Post by **Me-262** » Sun Sep 28, 2008 5:08 pm

Why not keep it simple and use the 500.2 as front stage ? I ran a pair of XS2500's (basically same amps) front & rear , you won't be dissapointed.

dako · Post by **dako** » Mon Sep 29, 2008 4:35 am

Man I'm dumb. I just realized that if I run another pair of RCAs back to the amp, I can run my comps active from the Alpine head unit.

HoseHead · Post by **HoseHead** » Mon Sep 29, 2008 6:17 am

RSD6.5cs driven by an HU amplifier??

Or do you mean swapping in the 600.4, dropping the 6.5cs passive Xover and using each 600.4 channel to drive a single speaker (mid or tweet) separately?

HH

Post by **stipud** » Mon Sep 29, 2008 6:57 am

HoseHead wrote:Or do you mean swapping in the 600.4, dropping the 6.5cs passive Xover and using each 600.4 channel to drive a single speaker (mid or tweet) separately?

Yep, that's "running active".

Your headunit would need to have to have a crossover good enough to do this... e.g. bandpass from 70Hz-2.5kHz for the midrange, and 2.5kHz+ for the tweeter.

dako · Post by **dako** » Mon Sep 29, 2008 9:14 am

I just read up on the CDA-9887 manual this morning and it looks like I'll be able to pull this off using the active x-over settings in the head unit and bypassing those on the 600.4. A set of RCAs will go to the front channel to run the mids, a set of RCAs will go to the rear channel to run the tweeters.

In 2.2 3-Way mode, the 9887 will run the following

Low: 20Hz to 200Hz (I'll set the x-over at 70Hz LP)
Mid: 20Hz to 20Khz (I'll set the x-over at 70Hz to 2.5kHz Band)
High: 20Hz to 20Khz (I'll set the x-over at 2.5kHz)

Looks like you can even adjust the x-over slopes from 6db all the way up to 24db.

Unless I'm missing something major, I think I should be able to pull this off with fairly decent results. The new amp rack I'm making should look pretty sweet with just a 1200.1 and a 600.4 sitting on it. Should be a lot less wiring clutter back there too since the passive x-overs will be out of the equation.

Post by **stipud** » Mon Sep 29, 2008 9:40 am

The 2.5kHz I used was just an example. You will want to play around with the settings and find out what sounds best in your install. This is part of what makes running active so good!

For example, this guy ran 2.5k on his mids, but left a gap and ran 4k and up on the tweeters, in order to avoid a shrill area around 3kHz in his install.
http://phoenixphorum.com/rsd-65cs-quest ... t6333.html

It seems that the little RSD tweeter doesn't like dropping too low, so I would say 3kHz or above would be best for it. Alternatively, since you are running active, you can change the tweeters out for something better at a later date. A set of larger Morel domes would match the sound very closely, but let you use a lower crossover frequency.

dako · Post by **dako** » Mon Sep 29, 2008 10:39 am

Cool. I really appreciate the info, not to mention getting some feedback kind of helps in the confidence department. Hopefully I can get this install wrapped up by the middle of next week so I can up some pics for you guys.