BuickMike's audio install thread

[BuickMike]

I am going somewhat old school with this since I'll be using crap that I have laying around.

I started mocking up stuff for the audio system. I had grandiose plans at first, but have scaled way back. Here is what I’ve done so far:

My headunit is an Eclipse 5303. It is super clean, but I hear noise from the servo on the CD player in the speakers when changing tracks and that bothers me. I may need to ditch it for something else if I can't fix that.

I’m using an old school Kenwood 5 band EQ / crossover. This is the 2nd gen one with the switchable display.

I had big plans to use my CDT 6.5's and incoporate some kick panels, but I decided to get lazy and just mount my Focal 136K polykevlar 5.25’s in the factory door locations.

 

[BuickMike]

I played around with the tweeters in different locations and found that mounting them under the dash in the corners and angled them towards the center. The driver’s side tweeter is a little shrouded, but I think it is acceptable.

 

[BuickMike]

I used Boston Acoustics plate speakers as rear fill. I just made adapter plates for them out of masonite to make them fit.

 

[BuickMike]

Here are the amps that I have:

Orion Xtreme 500.4 and an Orion XTR Pro 1000.

 

[BuickMike]

So this is where I'm at a point where I haven't made a final decision yet and need some input.

I temporarily hooked up my Orion Xtreme 500.4 with the front channels on all 4 speakers and bridged the rear channels to test the sub. The rear speakers were way louder, so I unhooked them for the moment. The imaging with the Focals is really impressive. Anything mono sounds like it comes right out of the center of the dash.

I hooked up my JBL 1000GTi in a 2 cu ft ported box facing backwards. It was LOUD. The sub wasn’t even being pushed that hard. The JBL is tight and clean, but just doesn’t sound very natural in the trunk like it does in a hatchback.

I then tried one RF Audiophile 10” in a 1.2 cu ft box ported at 35hz (this is the 1st gen, so you have to go ported) and it sounded real musical and clean. Looks like I’ll go that route.

--My initial idea was to go isobaric on 2 of these, but porting a .6 cu ft box at 35hz is pretty much impossible with a decent size port. I have enough room to put both of them in if I want.

So then I had an idea about the rear speakers. Instead of putting them on their own channels and turning down the gains, why not make them surround sound? Ever hear of left plus right and left minus extraction? If you take some rear speakers, connect the + terminals normally to the same channels as your front speakers, but tie the – terminals between the speakers together, they only play signals that either come out of one channel or the other. So I tried this, but added about 120 ohms resistance to the ground that connects them to quiet them down. All I can say is wow! This really opened up the soundstage. It does not sound processed or unnatural at all. BTW, you can run a wire from the connected rear speaker – side and connect it to the + terminal of a center channel speaker and connect the – terminal of the center channel speaker to either – speaker terminal on the amp. The center will only play mono signals.

I’m pretty content with this setup, so I’m thinking that I may just use one amp, but I'm still up in the air on the sub. Here are my ptions:
1. Bridge the rear channels to a single RF 10" Audiophile, however that is to many watts (250) for it to handle. I can aways turn the gain down though. I could make
an enclosure on the left rear of the trunk because I want to keep my spare, or put it at the front and face it backwards.

2. Run two 10" audiophiles facing backwards. The amp puts out 67watts RMS to each channel, and these subs are only rated at 75watts RMS, so perfect.

3. Run both amps. Put the Bostons on the rear channels of the 500.4 and run the 1000 (250W @ 4 ohms) o my JBL and just make it stupid loud.

4. Same as above, but go infinite baffle wit the JBL.

Thoughts? I'm kind of leaning towards option 2.

 

[rag231]

how is the sound of the sub getting into your car. I like the idea and choice of your rear speakers but you will blow the cones of those speakers when you push your subs hard. If you didnt have your rear fill speakers in, your subs would probably act a little differently, those holes flow air, faster than the sound trying to go thru your back seat. I had to completely eliminate rear fill speakers with my first option. Originally they were infinite baffle speakers until I went with the JL Audio flat subs (13tW5). My back seat top portion has been hollowed out and basically is a fake cover, the box is removable from inside the car, it slides into the trunk area. No trunk bar removal or trunk rattle. Very solid, very heavy box tho. Then I was able to keep rear fill speakers alive back there, but then I deleted them again. I didnt feel that they were needed. Love the Focals, I am on the hunt for a pair.

 

[BuickMike]

I've had several subs in this car over the years and had rear deck speakers. Ive always thought that I could be pushing them artificially, but have never caused any damage. If I have to I can isolate the rear deck speakers by making small enclosures for them. I don't have that rubberized mat anymore between the trunk and the seat. Plenty of sound gets in. I unloaded 6 cans of Boom Mat spray in the trunk and keep the bar spring isolated with some ruber tubing around them. No rattles at all. Not even outside.

 

[BuickMike]

I'm still debating on my amp setup. The 1000 is overkill and I don't want to take up all the real estate that it takes up. I am probably just going to go with the 500.4, but tonight I'm going to test my Xtant 404M. If the 404M can hang, then I will use that and save the Orions for another project. Here is the box I made. It is 1.2 cubic feet per side ported at 36hz. It is rear facing and I made it with 3/4" MDF. I don't have a table saw, but clamping a 4ft level on the wood and using my circular saw worked fantastic.

 

[BuickMike]

Here it is with the Orion mounted and the Audiophile subs in:

And I put it in the trunk to see how it looks and sounds. It fits well and sounds really good. Lots of bass considering each sub is only getting 50w RMS.

Once I figure out the amp situation I will start to do the finishing work.

 

[BuickMike]

Well, I'm ditching the Orion for the Xtant 404M. The Xtant is almost as loud, but just sounds more natural to me. Both amps are clean, but there were some harsh tones associated with certain frequencies that went away with the Xtant.

 

[Blazer406]

any updates?

I'm wanting to put some sound in my '87 GN without cutting anything up.

I have some old school Oz Audio separates, 2 old alpine 10's, 2 old school alpine amps (3552 ans 3554) and an old Soundstream D200 amp. I also have a bad ass HK CX-01 Crossover.

I'd like to replace my CSII door speakers, dash speakers, and rear deck speakers and install sub(s) in the trunk.... (possibly isobaric (7th order band pass?) taking up as little space as possible, easily removable, and ports extending through the back deck.

I already installed a newer Pioneer headunit (nothing too fancy) with bluetooth and hands free mic for cell phone connecting.

 

[BuickMike]

Sorry, I guess I abandoned this thread. Here is the rest:

Starting to carpet the trunk. I laid out jute padding and made a template for the floor. Then I cut the carpet to that template and used upholstery glue to put it together.

Carpeting the box:

So I used chipboard to make covers for the spare tire, left side, and amp wiring. Then I just carpeted that. It turned out good:

The Focals are super clean and the tweeter position worked out amazing! Seriously one of the better front sound stages I've heard. Using the resistors to quiet down the rear fill got it just right.

The subs sound a bit boomy and resonate really now, but are not punchy. My brother-in-law helped me clean it up a bit by experimenting. We put them in reverse phase to help with time alignment issues and also baffled the rear of the trunk as well as the spare tire cover. I'm going to maybe try cutting a port in the rear deck at some point and will also consider putting something with more midbass capabilities in the rear deck. I liked it better when I had 6x9's back there years ago. It is missing a bit in the midbass area.

 

[hawkfan]

Nice Xtant amp! You don't see those anymore. I also like your tweeter positioning. It keeps the tweets close to the mids, but aimed as if they were in kicks. Great idea. I'm working on my own install:

Pioneer DEH-80prs
JBL MS-52c no rear fill for now
Infinity Perfect 12.1D (already had it laying around, may change this)
Kenwood excelon xr900-5

My goal is to have a lightweight, efficient system with good imaging and SQ. I couldn't take the 3.5 and 6x9s anymore.

 

[Nasty Wendy]

What you've done looks very nice and clean. I'd be extremely tempted to leave it exactly as you have it just because it is so clean and uncomplicated. If I were to make any changes what I'd attempt is to move the rear X seat braces to the front side of the metal seat backing and mount the Xtant on the back side of the box (the Xtant seems to be the thinner of the amps you have). I'd then put the the Orion amp on the front (trunk) side of the box. The ONLY reason I'd attempt this is because more speakers are blown because they are under powered than because they are over powered. I'd like to see you put more clean power on your subs. Your mids/highs seem like a dream so I wouldn't change anything there. Every installer has a way of seeing things a little bit differently than the next. I like everything you've done so far I'd just like to see you use that clean power you have. If you had ISO loaded those subs you would have padded their 75w power handling but thats where our thinking strays. I would have opted to make the subs handle more power and send them more power at the expense of the install not being as simple, clean, & uncomplicated. Sometimes I could use some restraint in that thinking because there is truly nothing wrong with how you've done it.

 

[BuickMike]

Thanks for the advice Clay! I was hoping you would chime in on this. My initial intention was to do an isobaric setup with the subs, but I got lazy. I actually had HUGE plans for the audio in this car and scaled way back. You are right about the subs being under powered. I was just thinking about that yesterday. I could devote the Xtant to the mids / highs and put the Orion on the subs...or...what if I devote the Xtant to the subs (bridge front channels to one and rear channels to the other) and mount my Lanzar Opti Drive Plus 50 on the side or in front of the box and run the mids / highs off that? That would give each sub 200w RMS and my Lanzar OptiDrive 50 is super clean. It was rebuilt / upgraded my Steve Mantz himself. Thoughts on that?

 

[Nasty Wendy]

Your subs are rated to handle a total of 150w rms for the pair. Because they are in a ported box you don't want to grossly over power them either. If it were a sealed box I'd say go for it. I have found that ISO loaded subs have more excursion but not as much as a sealed box so ISO would only give a little more power handling. Not sure I'd put over twice what the subs are rated for on them in the ported or ISO box. I'd have no problems putting 200-250wrms on the pair in the ported box but more than that and you may burn the voice coils to easily. Why not bridge the rear channels of the Xtant on the subs giving them 200wrms and run the mids/highs on the front channels of the Xtant since you like how that amp sounds better? Even if your subs are 4Ω you could series them to 8Ω and run the gain twice as high on the sub channels as the highs channels.

Amps are rated to give different power at different impedance loads but the truth is that they will deliver their full power to any load. The output capabilities of an amp is determined by how much current the transistors can produce. Reducing the impedance of the speakers does the same thing as increasing the input gain to the amp as far as producing power goes. Both of these methods tax the output transistors for more current which produces more power. Keeping the amp with a load that it is designed to operate under is important to protect the internal circuitry of the amp but it can be worked around as well. You are always safe going up in impedance and compensating by adding input gain within reason. Run that Xtant at 8Ω bridged and the gains twice as high as the gains on the mid/high channels. One amp and a simple clean install that sounds good to you.

 

[BuickMike]

I can run them in series bridged and see how it works out. Thanks!

 

[Shawn N]

The side seat panels are a perfect place to mount rear fill speakers instead of the rear deck.

 

[BuickMike]

Yeah, I thought of that, but didn't want to mess up my new panels.

 

[Heisenberg]

Yeah, I thought of that, but didn't want to mess up my new panels.

I grab old rear quarter panel filler panels from the boneyard - and save any decent re-usable seat material when I recover seats.
That way - I can build up sets of qtr panel trim panels on the cheap.
Especially if you are putting a speaker in there - it really doesn't leave or require much in the way of pleating.
And truth be told - the panel itself is nothing more than thin glorified cardboard / chipboard.
A buck 2.90 from - anywhere - which for me - is usually a dumpster. ( Or the back of any junkyard trunk qtr liner / spare tire board)
Template; cut - viola'