Couple of questions regarding front speaker change

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sotal
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Couple of questions regarding front speaker change

Post by sotal » Fri Mar 30, 2018 4:48 pm

I'm currently fitting a pair of JBL GTO628 speakers in the front doors of the Bongo.

I've fitted the drivers speaker and just wanted to check I'd done it right before proceeding with the passenger side.

I did the following:

Removed the old speaker, and removed it from the plastic pod it sits in.
Used the black plastic spacer that came with the speakers between the pod on the speaker to move the speaker away from the door.
Trimmed the raised lip off the door card.
Put the clear plastic protector back over the edge of the speaker.
Made a couple of wires with spade connectors on to patch between the socket and the speaker.

With it like this the door card nearly sits on properly, the bottom lug is in and the screws are in but the area around the speaker sits slightly proud. Does this matter? If so what is the fix?

Secondly which way round do the wires go? I read that you should be able to tell when you've got them right. I tried both ways but couldn't tell a huge difference. Both sounded OK, one had a bit more bass than the other (I think), so I went with that way.

I only have one fitted so far and I've left it on the factory wiring but it doesn't sound a great deal better than the factory ones which was a little disappointing.

I'm using a Double DIN JVC headunit KW-R600BT- which says it has 4x50w - is this enough? I do have an old 2ch 200W amp somewhere but didn't really want the hassle of fitting that.

Will it sound better when both are fitted?

Do I need to replace the wiring?

I also fitted the bitumen backed sound deadening material in the door as I went.
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Re: Couple of questions regarding front speaker change

Post by Winnie-bongo » Fri Mar 30, 2018 5:57 pm

I have fitted JVC speakers in mine, using the original plastic mounting pods which I trimmed flat after removing the original speakers. I didn't need to use a spacer ring or grille so have no clearance issues I have put pictures up on facebook (can't seem to load them on here). I added some dodo sound deadening which has insulating properties and fitted a Vibe C-ven 8" sub behind the drivers seat in place of the dickey seat.

https://m.facebook.com/groups/252905573 ... 1129500733
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Re: Couple of questions regarding front speaker change

Post by sotal » Sat Mar 31, 2018 7:39 pm

Both speakers fitted now and sound deadening fitted to the inside of the doors.

The speakers do sound better, I had to fiddle with the audio songs to make them sound better.

Switching it to low amplification instead of high amplification seemed to make them better.
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ever after.
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Re: Couple of questions regarding front speaker change

Post by ever after. » Sun Apr 01, 2018 10:04 pm

I'm getting around 3 different answers on what the RMS power of those speakers are, all of which are over 50W so they should sound better run through the amp.

What kind of sound deadening did you use and where did you put it exactly. I'm getting a lot of rattles since putting in new speakers :roll:
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Re: Couple of questions regarding front speaker change

Post by Winnie-bongo » Sun Apr 01, 2018 11:16 pm

I just realised the op is using the GTO628 which are 2ohm speakers not 4ohm like normal car audio speakers halving the impedance will make the amplifier work harder and produce more power and heat problem is your jvc kwr600bt is only designed to run 4 to 8 ohm loads. Running 2ohm loads could damage it and will invalidate the warranty I have had to tell a customer his pioneer wasn't covered by warranty as he was running 2ohm loads.
So you would be better off running them off an amplifier if your amp is 2ohm stable in my opinion.
Silent coat is decent sound deadening but I used the dodo liner because of its insulating qualities, have only lined the insides of the front doors and around the speakers so far.

https://www.google.co.uk/url?sa=t&sourc ... m5fMV6s0vg
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Re: Couple of questions regarding front speaker change

Post by sotal » Mon Apr 02, 2018 12:17 am

The Sound Deadening stuff I got was called:

10 Sheets Sound Vibration Deadening Proofing Coat Mat Car Insulation Silent 4mm

It was £15.95 delivered for 10 sheets (approx a4 sized) from ebay.


Slight correction, the JVC is a KW-SD70BT - I was lazy last time and just googled until I found one that looked the same!

However the specs for the KW-SD70BT still say 4ohms (https://www.manualslib.com/manual/76891 ... ml?page=30)

I've got to say I don't really understand the ohm part, could I just wire them together to make it 4ohms? I'd lose the fact that it was stereo though I guess. Why do they make these 2ohm speakers if headunits aren't meant for them?

I'll go up in the loft and find the amp tomorrow. I removed it from a car I had, but in all honesty it was probably around 17 years ago, so maybe junk by now!
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Re: Couple of questions regarding front speaker change

Post by sotal » Mon Apr 02, 2018 4:48 pm

Right, found the old amp in the loft. It is a Rally by Caliber 260W CA-2260. It also has in the box a decent power cable with fuse and some oxygen free speaker cable.

The specs I can find on the net seem to suggest it can deliver 2x65w at 2ohm. So I take it that really I need to use this to drive the speakers?

I've now idea how to set it up though so will be searching for any info!
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Re: Couple of questions regarding front speaker change

Post by sotal » Mon Apr 02, 2018 10:06 pm

I had a quick look today but couldn't really find a suitable place to mount the amp, it looks like the stereo has a pair of RCA outputs which can be selected between speakers or a sub via the menu, so it should be able to be wired up OK. The ideal place wiring wise would be up behind the glove box but I'm not sure how safe it is there or what the vent type thing is?

The only other possible place I can see is in the kitchen cupboard, but that means much longer wire runs.
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Re: Couple of questions regarding front speaker change

Post by ever after. » Mon Apr 02, 2018 10:58 pm

I put mine just to the right of the passenger footwell.
It was literally the only place I could fit it in my van where it wasn't in the way :lol:

ImageIMG_1887 by Sodium Streets, on Flickr
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Re: Couple of questions regarding front speaker change

Post by Winnie-bongo » Mon Apr 02, 2018 11:30 pm

I have found the Bongo a hard vehicle to find space for amps or sub, ending up replacing the dickey seat with the c-ven active sub.
Your first problem is where to mount the amp, you can put behind trim panels but have to allow room for air for cooling. If it has fins they need to go upwards to allow them to work. It took me while to work out I could put my sub behind the drivers seat by using frame of dickey seat so it would swivel up to allow the seat to tip back as normal, so take your time and think where it might go.
Once you have worked out where it will fit I will happily offer advice. Most importantly the earth wire has to be at least as big as the power cable if not bigger and bolted/screwed to a good clean earth. Don't use seat or seat belt mounting bolts there are quite a few captive nuts you can use for earthing under the dash.
RCA leads and remote switch on wires also have to be run but you might want to put a switch in the remote wire so you can switch the front amp off when parked up and just use the rears. I always recommend only using amps with the engine running.
The gain control is not a volume but to match amp to stereo, to high and distortion which will kill speakers, we will get into settings once you are up and running so set it just below half to start. You want crossover set on full and bass boost turned down to start off.
Power cable beads to have fuse by battery and you need to choose which battery you want it off, I have stereo on leisure and amp on starter battery. There are large grommets each side to go through.
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Re: Couple of questions regarding front speaker change

Post by sotal » Tue Apr 03, 2018 12:17 am

Yes finding a spot for it seems the hardest part. I don't really want it visible. I'm not really after loud music, just good quality sound.

It sounds nice enough at the moment, but I'm aware that it might be damaging the head unit slowly.

I'll have another look behind the glove box to see if it can fit there at all.

Will probably run it from the leisure battery but the switch sounds a good idea to knock it off when the engine is off.
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