MK5 stereo install advice

[Greg Roles]

Boston S60 splits in the rears...



Dynamat city, with emphasis on the fronts and sub, as these are amp driven... incidently the sound deadener sheet on the passenger rear had fallen off and was a dried crumpled heap in the bottom of the door.

[Mr ©harisma]

Ha it's Boston city, good to see ha.

With Dynamat it usually works better in large sheets. Leave it whole and cut around what you don't need.

How are you going to trim the box?

[Greg Roles]

Front fascia will be matching carpet ( once I get a notion as to where to get a piece...), the top is covered by the rear right parcel shelf support, and the bottom I'm leaving "open" as I'm storing my mini compressor below there. All I have is a can for flat tyres now!

I hear you on the dynamat, the rears are running from the deck and will get the massive 18 watts RMS the 9887 pumps out. Add to that they'll be spared the bass via the deck, I don't expect a lot of resonance from the rear doors.

Fronts are a different matter, and I have a lot of dynamat left just for the front doors, and the boot panels once I get it working. The front Pro's, will get 187 rms watts from the Soundstream, as they are 3 ohm. I expect a lot more resonance there! Any advice where you'd crossover the mids and sub?

Added 500mL to the box volume today, so as near i can approximate with garbage bags filled with water, I've got the desired 8.5L. Spent today making sure it's air tight, solid, and painted all the mdf just in case it gets wet.

[Greg Roles]

OK, well my amp is wired up and the sub is powered, and performing quite nicely for a "rough" gain/sub level setup. Still playing with the crossover in the Alpine, but seems that 80Hz with a 12db rolloff on the doors and 6db on the sub is sounding pretty nice. Hard to make a system suit everything from Techno to U2 to FM radio, but I guess I can store several Eq curves and swap to suit. What do you legend audio types do?

So far only have the rear door Boston's in, running from the deck, once I get the Pro's into the front doors in the next several days, I hope to do some more fine tuning. Without a lot of exploration in the boot, it seems the only "rattle" is the boot vent system, on the passenger side behind the carpet ( below my sub setup ). This is doing what it has done in previous cars, and the rubber flaps are buzzing after every kick. Can't hear it in the drivers seat, but with the boot open it's very obvious. Apart from that I can only make the outer door handles rattle, pretty happy with the lack of rattling overall !

The downside is my sub fascia looks friggen horrible, and is nowhere near the right shape. Is airtight and doing the job nicely for a little 8", but I'm so ashamed I don't even want to post a pic!

Version #2 fascia will be next on the list!

Also after some ideas for some nice sub bars to protect the speaker, as it's on top of the "box, and a stock 8" grill from Jaycar isn't "deep" enough.

[benno]

Greg how do you find it without the mid range drivers in the front doors and the bass driver back by your thigh?

I have a pair of Herts splits I want to chuck in but I'm wondering about this... and how much of an issue is speaker depth for the 6.5"?

Any tips for door trim removal?

[Greg Roles]

You won't believe it mate, but I've yet to finish the front door installs. Driuver and tweeter into passenger, but still have to pass the wire through to the door. Yet to do drivers side. Hope to get it done in the next week or sa, as I'm hoping to start a new job, and at first my spare time will be minimal.

Doors come off easy, grab handle outer levers off, torx in the handle and two at the bottom, then clips around the base and sides, disconnect window and speakers, and unhook door opener. Just take your time and be careful.

I'll update the thread and answer your question once I have them installed and powered!

[benno]

Doors come off easy, grab handle outer levers off, torx in the handle and two at the bottom, then clips around the base and sides, disconnect window and speakers, and unhook door opener. Just take your time and be careful.
!

Can you elaborate on this at all? I'm struggling with the passenger side at the moment. I think I can see how the drivers side goes.

I can't get the trim around the grab handle off, and I presume there's some fixings in there.

Also, the door handle?

[Greg Roles]

Well a big thanks to Benno, who has motivated me to flippin finish my stereo install. Too many projects on the go at the moment, but seems to always be the way, so I just got stuck into it.

So a big thanks mate!

I did run thick wires right to the speaker, and actually found going through the door wire shrouds relatively easy, there was certainly plenty of room, and even a nice gap in the metal down the bottom.

So today all I've left to do is hook up the crossovers in the front, then it's tuning time.

I sent the following e-mail direct to Boston Acoustics, who are exceptional in their response time, but the reply does confuse me a little. Perhaps some of you guys can explain it to me.

My e-mail: ******************************************

I've just finished installing some Pro60's in the front, some S60's rear, and a nice G108 sub in a VW hatchback. The sub is in the recommended 8.5L sealed enclosure runing 2 ohm.
Fronts and sub amplified, with plenty of headroom in the amp, an old US Soundstream VGA 500.4. Sadly I don't have the clever Q of a Boston amp, but can adjust the Hawkins control in both Hz and boost if necessary.

I'm about to start tuning it, and wondered if you could suggest a good starting point for the HPF out of my Alpine 9887, specifically to aim for non localised bass from the rear.

I was thinking somewhere 70-100Hz for the sub at 6bd rolloff, same setting for the rears at 12db, and perhaps 10Hz overlap in the fronts at 12/24db. Component setups, F / R at -2db tweets. The front tweets are in the A-pillar so perhaps -4db?

************************************************** ****
here's the reply, but it's the GAP that has me confused...

Hello Greg,

I would set the interiors to a HPF of 125 Hz, the sub at about 90-100 Hz or lower depending on your style of music. Set your tweeter to 0Db for best sound and S/Q. If you want your bass to drag set the sub to a higher octave (24) if you want it fast and punch set it to (12db). Thank you taking pride in S/Q, I do not see that too much anymore.



Why the gap between mids and sub????

[Greg Roles]

[Greg Roles]

Wiring is even better now you wire nazi's...



Amp hardly ever get's warm, but so too has it only been powering the sub a bit...

[benno]

Nice.

So you put your 6.5" driver in the stocko plastic ring as well? It seems pretty decent to me with a bit of dynamat added, and it seals properly in the door card.

That gap between mids/sub seems odd to me... maybe he got the numbers backwards? I.e 125 hz for the sub and 90-100 for the splits?

You don't live in Toowong/Auchenflower do you? I've seen a grey GT TDI with roof racks around there...

[Greg Roles]

The stock plastic ring is solid enough for me, I bolted mine back in as well as silastic, and as you say a little dynamat and it's plenty good enough. That and the fact I just want to finish this install!!

My only concern with the high mount tweets is that they will be too "harsh". Also, given they are flush, will throw the focus down according to an interesting article on acoustic centres I read on the soundstream site. Several interesting articles on there, and I took the guys advice about "porting" the parcel shelf to let more bass into the cabin, and cut the inner edge off the parcelshelf, where the fold line is.

With the boot shut there's a finger width gap along the parcel shelf which I think will do the job nicely. I didn't notice much more, if any road noise withthe parcel entirely out, so I don't see any issue.

I will only own up to working at Toowong if I haven't cut you off, flipped you the bird, or whistled at your girlie.

[benno]

My only concern with the high mount tweets is that they will be too "harsh". Also, given they are flush, will throw the focus down according to an interesting article on acoustic centres I read on the soundstream site. Several interesting articles on there,

Hmmm just DLd a few articles. I'd kinda like to experiment with position of the tweeters etc, but I'm not sure I can be bothered. I wonder if new tweeter trim panels are available?

I will only own up to working at Toowong if I haven't cut you off, flipped you the bird, or whistled at your girlie.

Nah but you were parked just around the corner from my sisters place

[Mr ©harisma]

You only really need to try the tweeter mounting in about 4 places:
- High in the kick panels
- Near the woofer on the door
- At the base of the A pillar
- At the section where the windscreen meets the dash

Try those places at different angles wit blu tac and see how you like it. If you mount it down low, be sure not to attenuate the tweeter.

[Greg Roles]

Well it's all done, and in, and all I can say is WOW. The teewts in the A pillar, on zero db gives a nice high, slightly up front sound stage, even without time alignment. Leave em where they are Benno!

Ran just the F/R mids over the weekend while the new fascia for the sub was allowed to dry, and I experimented getting the gains just right with absolutely no effect or equaliser, and the sound was good even then. With a rock Eq curve and some Apline MX effect, the mid bass kick and top end response was just awesome. It's a bit "bright" in the mid upper somewhere, but I picked up a simple DB meter today from Jaycar, and have a pink noise CD coming, so I will be able to work out a nice even eq setting and tune by taste from there.

As for the little G1008 8" woofer, I just can't believe the bass kick that is coming out of it, spent a lot of time working out my poorly described VGA amp, and I had the input voltage setting too high for the Alpine preouts. Now it's back to <4V the response is just amazing. Whilst it doesn't go quite as low as a 12" in a big box, I have to say that it's performing down to around 40Hz, and with a bit of boost at about 40Hz as recommended by Boston, it's just superb. At a 12db rolloff it's a very tight kick. I'm amazed a little woofer can sound this good. It's not rattling the rear vision mirror like a big 12" does, but I'm sure feeling the bass through my ribs, and even at 80Hz hpf it's quite non localised. I set the mids at 125Hz rear and 100Hz front for now, and it is a pretty darn good sound for a rough tune. Much tweaking to come.

Again a big thanks to Benno, for getting me motivated to do the last 20% to complete the install. I've one rattle in the rear passenger door trim, but apart from that she sounds tight as a drum. Very happy!

The best news is I still have a spare 250RMS sub channel going to waste, so adding a second G1008 would be all too easy....