Stereo fitting / set up advice needed!?

[orangebooboobearcrew]

Hi,

We were lucky enough to be bought a new head unit for Xmas and I am just in the process of trying to fit this - albeit I have never done this before so kinda learning as I go...

The unit is a JVC KD-R701 and the instruction book states speaker output is 4 x 19W (RMS, Max is 50W) at 4ohms.

I want to get a decent quality of sound and wondered if anyone had any suggestions as to best set up. I was thinking about 2 x Infinity Kappa 4" (10cm) 42.9i full range speakers in the doors with a sub of c 500W RMS under the R&R bed, powered by a mono channel amp? Any ideas what this might sound like quality wise.

I am a bit limited for space in the back of the bus but as the head has 4 speaker outputs it would be also nice to be able to fit rear speakers as well (probably same Infinity speakers again). Could I do this so total set up would be 2 front speakers, 2 rears speakers + rear sub? If so, would I be best to run all speakers off an amp and how many channels would it need to be? Given that 19w doesn't sound like a lot of output, presume amp would be best option to get decent sound but then these speakers only rated at 50W RMS so would it be worth it?

Also, which round do you rate speakers at?; by that I mean if a sub is rated at 500W RMS, does the amp need to be rated at +500W RMS? Also, if the head output is 19W RMS, do the speakers need to be rated at +19W RMS?

Thanks for any help anyone can give...

Chris

[orangebooboobearcrew]

Do I take that as no one knows the answers to this one or just that no one cares ???

[j4jon]

Hi,

We were lucky enough to be bought a new head unit for Xmas and I am just in the process of trying to fit this - albeit I have never done this before so kinda learning as I go...

The unit is a JVC KD-R701 and the instruction book states speaker output is 4 x 19W (RMS, Max is 50W) at 4ohms.

I want to get a decent quality of sound and wondered if anyone had any suggestions as to best set up. I was thinking about 2 x Infinity Kappa 4" (10cm) 42.9i full range speakers in the doors with a sub of c 500W RMS under the R&R bed, powered by a mono channel amp? Any ideas what this might sound like quality wise.

I am a bit limited for space in the back of the bus but as the head has 4 speaker outputs it would be also nice to be able to fit rear speakers as well (probably same Infinity speakers again). Could I do this so total set up would be 2 front speakers, 2 rears speakers + rear sub? If so, would I be best to run all speakers off an amp and how many channels would it need to be? Given that 19w doesn't sound like a lot of output, presume amp would be best option to get decent sound but then these speakers only rated at 50W RMS so would it be worth it?

Also, which round do you rate speakers at?; by that I mean if a sub is rated at 500W RMS, does the amp need to be rated at +500W RMS? Also, if the head output is 19W RMS, do the speakers need to be rated at +19W RMS?

Thanks for any help anyone can give...

Chris

OK Lets see if we can help.
Yes your plan of 2 front, 2 rear and a sub would be fine. You will be fine to run the Kappa's direct from the head unit. I might be tempted to go for the 52.9s at least in the back as they are slightly larger and the T25 is a big space to fill. You will definitely need an amp to run the sub and depending on the sub and its rating depends on the amp you would need, either a mono or a dual channel amp that can be bridged to create a single channel, (unless you want to run two subs?)

As to which way round you rate the speakers. You don't want a much bigger amp than the speakers, for example don't buy a 1000w amp and then connect it to a 200w speaker as then you could blow the speaker. The same can be said of the other way round to so don't buy a 1000w speaker and try and run it on a 200w amp as you end up working the amp too hard and then it can clip and damage the speaker. A small difference is ok just don't get carried away.

If you buy some good speakers then you don't need huge power to create a decent sound and 19wrms for full range speakers should be fine for normal listening unless you are trying to win a sound off competition.

Hope that provides some help.

[CovKid]

I've done the same thing in two T25s and that was to mount two midrange speakers right up under the dash (made easier as I did it when dash was out) with tweeters on dash top. I get an amazing sound without even dealing with door speakers. Sounds nuts but it does work.

[orangebooboobearcrew]

Brill! thanks both for your answers - it's nice to know someone cares Sorry if I'm asking basic and simple questions but it's all a bit of a mystery to me but want to learn how to do it...

I've ordered the 42.9 Kappas now for the front door panels and hope to get them installed next weekend with a fair wind... Just gotta save up now for the amp and sub and will do that next...

As I am limited for space in the back as I said, gonna go just for a sub with amp, probably something around the 300 - 400 watts rms mark for sub output. So, if I got a sub with a 400w rms output, would a 500w rms amp be okay or could I get away with a 300w amp?

Cheers,

Chris

[j4jon]

You could get away with a 300w amp and it would be fine. Have you got a sub in mind? What size are you thinking of in the way of a sub 8", 10", 12"?

[orangebooboobearcrew]

Hi Jon,

Was thinking about a 10" sub as this will be the biggest I can fit in the space I have - not sure which one yet though...any suggestions?

Cheers,

Chris

[j4jon]

For a sub you could get something like a 10" JL which I've used before (and I'm not just saying that as it's my initials)
http://www.caraudiodirect.co.uk/jl-audio-10w0v2.html" onclick="window.open(this.href);return false;

And then to run it something like a mono block Alpine amp
http://www.caraudiodirect.co.uk/alpine-mrp-m352.html" onclick="window.open(this.href);return false;

That should give you good punchy bass. Are you aware that a sub should be installed in either a sealed box or a ported box?

[orangebooboobearcrew]

Cheers Jon,

Looks like a really good option and not mega pricey either (I used Car Audio Direct for the head unit and door speakers and they seem really good!)...thanks for your help with this.

I am aware that a sub needs to be housed in an enclosed space but was hoping by installing it in the front of our Blubird R&R bed plinthe, this would be sufficent with the space behind this acting as the 'enclosure'? This isn't totally sealed as there are small gaps at either end of the plinthe between the cabinets / bodywork - is this likely to cause any noticeable issue with sound / bass quality? (FYI - I also have under the bed currently (behind the plinthe) the 240v fuse box, on board water tank and secondary fusebox for leisure battery).

Cheers,

Chris F

[orangebooboobearcrew]

Also, I have seen various posts stating that as the doors on campers are designed to let water pass through - do the speakers need to be protected from this water and if so how do you do it - wrap them in polythene?

Ta,

Chris

[eatcustard]

Modern car speakers cones are made from plastic so are water proof

[_robin]

I've done the same thing in two T25s and that was to mount two midrange speakers right up under the dash (made easier as I did it when dash was out) with tweeters on dash top. I get an amazing sound without even dealing with door speakers. Sounds nuts but it does work.

That sounds interesting - got any pics?