CDA 9887, Imprint Tuned Center Channel

[aworldcollision 10+ year member]

Thought this may be interesting to somebody. The 6 channels of the 9887 are full range. This means that after running a 3 way active system, if only using one subwoofer, the 6th output can be mounted in the center and Imprint tuned. The only downside has been that you need to run a bass knob for your subwoofer since your center channel and sub will be tied together.

This will give you the ability to maintain a higher SPL while keeping your highs and mids balanced since there can be, after all, 50% more drivers to share the load.

Stereo seperation is fine. I found no shrinking front stage problem. Tonality is perfect. Obviously the front stage is solid.

With all center speakers it is important to keep driver types unifmor as well as sensitivy considerations. Otherise you'll get varying responses at different output levels.

I installed a five inch, a five inch+3.5 inch +tweet, and now have two 3.5's installed. These are dome mids and sound great but will lack low-end response that you would get from a cone driver like the 5 inch.

This was/is an experiment that is successful enough that I figure it may be useful to others. I'd like to hear other experiences.

Remember that Audyssey is a hometheater tuning prgram. I believe that the Alpine has the same version just teaked a bit to tie the two subs together for car audio.

Click to read more...

 

[Buck 5,000+ posts]

who is dis

 

[James Bang 5,000+ posts]

who is dis

stfu. doesn't matter.

 

[aworldcollision 10+ year member]

who is dis

umm...

stfu. doesn't matter.

I'm going to go with his answer

Howdy James.

 

[James Bang 5,000+ posts]

Is it a TRUE center channel though? I'm thinking it just might be l/r summed..

 

[aworldcollision 10+ year member]

Here's an image. Two CDM 88's driven at 8 ohms by a Sinfoni 150.2x. I figure about 350 watts to the center to make a nice and easy, laid back sound.

Considering the position, the five inch may have been the better to take care of beaming issues caused by drivers pointed at ankles. If SPL were my goal, I would have kept a center mounted tweeter. As it is, these are the pooridge in the middle

Each driver, except the sub, is pushed by a matching amp providing about 170 watts RMS to each driver.

 

[aworldcollision 10+ year member]

Is it a TRUE center channel though? I'm thinking it just might be l/r summed..

I wish I could say. Honestly, I do believe this to be the same processing as the home theater version but I can't tell. Audyssey is great for keeping secrets.

I hooked this up this way thinking it must be a L/R summed signal that would have the programmed repsonse applied to it but it seems to be more intuitive than simple pro-logic 2. If it is a simple summed signal it has to be seperately summed from the right sub to apply seperate time allignment (I know, I was just spelling it out for everyone else)

I think that's wrong, though. The staging is really too perfect. The balance is not just aall right, all center then all left. There are subtle variations as dynamic as the music itself. I don't know how the logarithms work but I feel it is just a realligned 5.1 program rerouted for car use. I'm worried about using my sub controls for fear of blowing the center but in reality, it seems to have measured for that as well.

I wish I knew how it works but since it works, I've not tried to fix it

 

[psychoacoustics 10+ year member]

so i an run my epicenter off of the sub channel? hmmmmmmmm

thanks im gonna have to experiment ill respond this weekend

 

[aworldcollision 10+ year member]

so i an run my epicenter off of the sub channel? hmmmmmmmm
thanks im gonna have to experiment ill respond this weekend

epicenter? why would you do that except to serve as the opposite of the bass knob and have a center control knob...nevermind. May be a great idea. The epicenter hooks to the left and right, though, correct? Make sure it is just the left sub output so that time alligment isn't nullified.

You will be the second person to try it and I'm sure you'll like it.

 

[psychoacoustics 10+ year member]

well its just a toy to see if it helps with bass race might not work ????

or i might use it to run another 4 channel for the other 2 component sets for when the doors are open at a show

how doe sit not have a lp xover though? i ran my 3way and didnt use the xovers in my sub amp with out getting hf through it?

i will test this out with my rta this weekend and a few sets of rca to phono adapters

can you please explain how you found this or what made you think of it ?

 

[psychoacoustics 10+ year member]

oh and ill check if its left right or L+r too

 

[aworldcollision 10+ year member]

I can't for the life of me think why you would have more than one setof comps.

As far as lowpass settings, imprint reads the mechanical noises that are indicative of driver limitations and sets the limits to that. I truly believed that when I hooked up dome mids with an effective range of 300-7k. I also had about 600 watts RMS to them

That's my hesitation with the epicenter. Honestly, if you don't try to trick Imprint too much it will do the job. Remebering your equipments' limitations is one thing, outright challenging yourself to fail is another. If you have pasive crossovers, I don't see a problem with hooking anything up, period. SinceI've hooked up the full scope of possibilities, I know it can be done.

I truly believe this is the road to SQL...in speite of my feelings for that phrase, its impossible to hit these SPL numbers with no distortion to...what? The tweeters. If SPL is yourneed plus you'd like some SQ, I suggest a center channel to take some stress off of your let and right tweeter. Surprisingly, you won't lose any spaciousnessthat stereo provides as long as you are carefull about driver placement and vehicle acoustics.

I didn't find this, I thoughtit up while considering the JBL MS-8 problem. I don't believe that I'll ever have the drive to RTA each dip and peak to exhaustion. I'm an auto-tune man. However, stereo just doesn't work in a car. So I figured that a sub channel will be mono anyway, just like a center channel, so whynot see what Imprint would do with the tuning. I was using a 5 inch peerless I got from PE for 10 since it was a lost cause anyway. It sounds great.

I spent the next few days running Imprint a dozen times with a dozen speaker configurations. I won't say Ichose the one with the best sound a I believe I could do better but my insall isn't complete and using Imprint to fix a bad install IS WRONG! Yu'll get no bass and low output.

Hint: lways run Imprint on the first position. Then hit the results button. The ruslts will give you a basic FR plot but won't be able to apply spacial averaging. IOW, run the first position, run the results. With that graph, fix driver phase, gains....then, witha much better ida of shortcomings run the full test. You'll be happy

 

[psychoacoustics 10+ year member]

cool

well imagination is the key

i have hlcds and 7" mids in pods and no passive xovers just active

so i dont need a cernter but........i have the previous setup still installed not being used kicker 6.5' ss comps all around but they arent on and of course i wont power them during critical listening just when the doors are open at a show to keep up with 8k of power going to the woofers

im kinda new to the imprint ive only used mine 3 times ? so im trying to learn as much as it as possible funny how you can trick it

the epicenter is just a test might dump it if it dont work

 

[aworldcollision 10+ year member]

http://www.diymobileaudio.com/forum/member-product-reviews/22136-alpine-cda-9887-imprint-kit-ktx-100eq.html

There are alot of Imprint tricks in this thread. Most noteably important is to reduce gains before running Imprint (by about half) then turn them back up after Imprint is ran. Audyssey attempt to be conservative but that's not really our style.

I honestly don't know what will/can happen when it comes to 8k of power to subs...I'd think you'd have some imaging problems

I wouldn't worry about running the drivers active as Imprint will respect the crossovers you set as well as testing for mechanical limitations. Imprint doesn't care what you set your sub crossovers at, it will change them.

 

[aworldcollision 10+ year member]

cool
well imagination is the key

i have hlcds and 7" mids in pods and no passive xovers just active

so i dont need a cernter but........i have the previous setup still installed not being used kicker 6.5' ss comps all around but they arent on and of course i wont power them during critical listening just when the doors are open at a show to keep up with 8k of power going to the woofers

im kinda new to the imprint ive only used mine 3 times ? so im trying to learn as much as it as possible funny how you can trick it

the epicenter is just a test might dump it if it dont work

did you try it?

I am probably going to go back with a five inch center as I prefer the dynamics. Its tough giving up the richness of the domes, though. If I get kickpanels installed this weekend I'll keep domes in..

just checking on progress...