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[Martin_1962]

Any problems with running CD Changer, H/U to amp and a speaker cable next to each other.

Or with power supply and speaker cable.


Thanks

[Jay w]

ive never had an issue, although i do try and ensure that power leads are shielded.....bit extreme i know

[Dave DND]

Keep main power feed to amplifier away from the low level inputs, output speaker cables not so important.

if running an aftermarket amp, the prefferred method is RCA and any signal cables down one side of the car and the heavy power cable down the other. This will eliminate RF interference from the power cable reaching the amp or low level signal inputs.

But the most important thing is your earth location - it must be good!

[Martin_1962]

I am planning power down the L/H side (following my fridge/charging wire and multivalve wires), low level from H/U following the CD changer on the R/H side.

The amp will be mounted at an angle vertically behind a rear seat in the dead space between the seat backs and the tank.

How big does the cable need to be - 80w RMS per channel 2 channel?

Will be driven at about 40w maximum.

The speaker cables will be returning up the cill areas to the front doors.

[Martin_1962]

Earth - chassis earth OK?

[Dave DND]

Not sure where Fuel pump is in the Omega, just make sure signal cables avoid it if possible, otherwise your cable runs sound ok.

As thats quite a large amp, I would advise a minimum of 4 gauge power cable for live and earth - remembering to use grommets and fuses where necessary.

Earth cable needs to be as short as possible, and screwed into a fresh bright shiny hole in the floor chassis, ideally where the floor meets the suspension turret in the boot, as there are fewer voltage losses here between welded panels and seam sealant.

If you fancy a laugh, and you want to see how others have got it wrong, take a look at this link of some of the customers that have turned up on our doorstep !!

http://www.dndservices.co.uk/htmls/flash_htmls/blackmuseum.htm

[Kevin Wood]

I am planning power down the L/H side (following my fridge/charging wire and multivalve wires), low level from H/U following the CD changer on the R/H side.

This is exactly what I did and it works fine. LHS is the obvious way to route power cable and putting the signals down the RHS keeps them away from this and the rest of the car electrics.

How big does the cable need to be - 80w RMS per channel 2 channel?
Will be driven at about 40w maximum.

Probably 30 amp although you'll get away with smaller. Just make sure it's fused at what the cable is rated at, at the battery.

Earth - chassis earth OK?

Yep. Just connect it to the nearest earth point or make a new one. Parcel shelf sounds favourite.

Kevin

[Martin_1962]

Not sure where Fuel pump is in the Omega, just make sure signal cables avoid it if possible, otherwise your cable runs sound ok.

As thats quite a large amp, I would advise a minimum of 4 gauge power cable for live and earth - remembering to use grommets and fuses where necessary.

Earth cable needs to be as short as possible, and screwed into a fresh bright shiny hole in the floor chassis, ideally where the floor meets the suspension turret in the boot, as there are fewer voltage losses here between welded panels and seam sealant.

If you fancy a laugh, and you want to see how others have got it wrong, take a look at this link of some of the customers that have turned up on our doorstep !!

http://www.dndservices.co.uk/htmls/flash_htmls/blackmuseum.htm

I have seen this - scarey!

I have got a FOC amp, not good but if it sounds bad I can replace it.

Speakers - I am fitting Infinity 605CS, I had them in the blue 2.0CD as an original was burnt out. They cost me enough so I am reusing them!!

Just need to find the manual for the MD unit as I need a trigger wire for the amp.

No room behind the H/U - got a connects2 adaptor and I tried to fit an instruction and lead less Autoleads traffic master adaptor, (bought for a fraction of cost).

Not sure what to do about the back doors

[Dave DND]

If you are using a cheapie amp, you can get away with an 8 gauge fitting kit, but use a 4 gauge kit with a good quality amp. If, as suggested, you use a 30amp cable, then you will have a large heating element throughout the length of the car, and you will see from my weblink what this can do!

Do not use the parcel shelf for an earth, as the voltage loss through the extra welded joints will give interference issues.

A trip to your local audio shop for an amp fitting kit would be advised, as it will come with all the necessary connectors and fuseholders that will be of the correct rating for your installation.

[Kevin Wood]

Make sure the cable is fused appropriately at the battery and whatever cable you use, the worst that can happen is that the fuse will blow. If the power ratings are honest and the amp is 50% efficient you have 26 amps draw at continuous full output.

I found most fitting kits to be too short for the Omega as you'll need 7 metres give or take a little to get from the battery to the boot. I found plenty of 5 metre kits for sale but finding anything longer was a challenge in the usual Hafords type places, and their cable sold by the metre was insane prices, although pretty.

In the end I bought the cable and fuseholder, connectors, etc. from Here http://wwww.vehicle-wiring-products.co.uk/. Not as blingy but better value.

Kevin

[Martin_1962]

If you are using a cheapie amp, you can get away with an 8 gauge fitting kit, but use a 4 gauge kit with a good quality amp. If, as suggested, you use a 30amp cable, then you will have a large heating element throughout the length of the car, and you will see from my weblink what this can do!

Do not use the parcel shelf for an earth, as the voltage loss through the extra welded joints will give interference issues.

A trip to your local audio shop for an amp fitting kit would be advised, as it will come with all the necessary connectors and fuseholders that will be of the correct rating for your installation.

Cheap - I got it off freecycle

I'll check maplins again for cables next weekend.

There are some earthing points near

[Martin_1962]

Make sure the cable is fused appropriately at the battery and whatever cable you use, the worst that can happen is that the fuse will blow. If the power ratings are honest and the amp is 50% efficient you have 26 amps draw at continuous full output.

I found most fitting kits to be too short for the Omega as you'll need 7 metres give or take a little to get from the battery to the boot. I found plenty of 5 metre kits for sale but finding anything longer was a challenge in the usual Hafords type places, and their cable sold by the metre was insane prices, although pretty.

In the end I bought the cable and fuseholder, connectors, etc. from Here http://wwww.vehicle-wiring-products.co.uk/. Not as blingy but better value.

Kevin

Bit of a pain as I threaded a load through in 2006 fridge/charger, multivalve solenoid, gas level and the LPG earth. Earth points will be hunted for.

[Kevin Wood]

Sounds like your sill covers are going to be getting fairly busy

I found Maplin had a pretty poor range of vehicle cable. Ended up buying 6mm² thinwall automotive from VWP at under a quid a metre, IIRC. Rated at 50 amps. Reasonably compact if you're trying to thread it through tight areas too.

Got a Maxi-blade fuse holder with fuse to go by the battery too.

Kevin

[Martin_1962]

Amp won't take much over 3mm in its terminals, so I'll go for that and fuse accordingly.

[Marks DTM Calib]

80W RMS is about 120W peek.

Assuming 70ish percent efficiency in the audio stage gets you to 170W and then the DC-DC will be about 90% efficient (if its a good one) which gives about 190W input for 80W RMS ouput.

This assumes a reasonable class AB output stage (which car audio rarely is) so its pretty worst case (as it should be).

So times 2 for both channels gives 380W input at peek points.

Assume a 12V supply as there will be some volt drop across the cable and because there is a DC-DC in the equation which will just up the current drawn at lower volts.

This gives 31A worst case....

For this I would be looking at a 38A fuse (slow blow) or 42A breaker (type 2).....and cable to suit!