Power From Head Unit

[Guest docter fox]

i have just bought a cd head unit (car radio) from france, all the instructions are in french so im having trouble translating but i dont normally read then anyway

 

back to the point... it claims to have a 4x45 watt output so has 8 terminals to attach the speakers to via a clip thingy

 

as cd's are only played in stereo (2way), if i were to link the 4 wires from the right side (2 positive and 2 negative) to one speaker, and do the same with the left, would this give me a theoretical 2x90 watts power output? or would it just go bang? thought id check before trying, to be safe

 

dont know if that made any sense but thanks for any help

 

The Docter

[Dave R]

got a make and model number for it ?

maybe a google search if its a well known brand will bring up something

[Guest salty_monk]

You can't join the 2 channels in together otherwise it'll go bang! They also go bang if you accidentally earth them out - I've done it!

[Guest docter fox]

glad i checked

its big in france but not anywhere else, iv found a website and with the help of google translator il get ther eventually

 

is there any crossover type thing i could get that would connect them or should i just stick with connecting it directly?

[Guest Mr Pid]

Yeah you can get crossovers for fiting speakers, these also help if your fitting tweeters in instead of piggy backing of your main speakers. You can also get crossovers which filter out certain frequencies depending on how you like your music to sound.

 

To make a speaker sound good you ideally want about 2/3 of the speakers total power output going into it. It really depends on the quality of speaker on how good your music will sound, not the head unit (to a certain extent of course).

 

Stu

[Guest docter fox]

i bought a couple of floor standing speakers to fit (get to fitting later)

they have 3 speakers in each and are 150 watts RMS each theyv got crossovers inside so basically i just need 2 provide the input to the speakers through 2 wires as you would normally connect one speaker

 

is ther a crossover type thing that can connect 2 inputs into one (only seen them the other way round) if not is there any way of doing it without an amp?

 

dont know how loud it would be connected straight to the head unit as i havnt got that working yet

 

how loud does a stereo have to be before you can hear it reasonably while driving?

[Guest Tim Norman]

I have found that anything over about 40mph and you can't tell quality sound from crap sound coming from your speakers.

[Guest Mr Pid]

Are they house speakers? They will work if they are but the sound will be much better from proper car speakers. Check Ebay as there are usually loads cheap as chips on there.

 

I had a 120w amp in my car, which blew so i had to fit the only one i had left which was 400w, only just managed to squeeze it in the boot! It is proper loud though!

 

I dont ever remember seeing a gadget which combines two positives.

 

Stu

[Guest docter fox]

i got 6 speakers off ebay a while ago, 2 woofer, 2 mid range and 2 tweeters that can take a total of 700 watts RMS and was going to fit them but realised that with an amp i would have even less boot space and when i saw these although they are pretty big i thought about things carefully but when i heard them i couldnt resist

 

plus i can now find a way of incorporating the 2 subs into my home cinema surround system

 

i tried the speakers with about 2x40 watts and they will be loud enough for a small car, they sound a lot better than some of the sound systems iv heard with more power so it'l do for now i suppose. I took them up to 2x80 and that made the whole car vibrate so i can only imagine what they would be like if i got an amp to take em to 2x150watts

 

il stick with using 2 of the outputs at 45 each and just have a couple of wires somewhere that i could connect to my stereo system when im in the garage

 

Mr Pid

 

400 watts! bet thats loud when your sat so close to the speakers

what speaker set up have you got?

 

do many people hace stereos fitted?

 

if you also connected up the radio what type of aerial and where did you mount it?

[IanS]

Hi Fi power is a bit of a con. The only true way to measure power is continuous RMS with sine excitation. BUT by taking instantanious peak power you get more impressive numbers.

 

When I built my first Hi Fi 35 years ago a genuine 30 watts was very loud in a car.

 

Since then 30 watts appears to be got out of a 9V battery that then lasts for days, something has gone wrong with chemistry and maths in these add prone days.

 

You can get devices to add the power from 2 sources, they are called transformers with 2 primaries and a single secondary. Unfortunatly the price of one to do the job you want will be high as very few firms now make wide bandwith audio transformers and what you want is probably now a made to order device.

 

Also modern speakers are small and handle the power by turning most of it to heat not sound.

 

Time to get off my high horse.

[Guest Dredd]

Can you wire the speaker output to headphone sockets? It seems a better deal to wera headphones rather than let the sound drift out of the car and annoy the neighbours

[Guest docter fox]

not sure id like headphones all the time but i may see if i can wire up the rear speakers to a couple of sets of headphones and use the fader to put it either front or back.

 

Thanks for the suggestion