Amp to power ratio?

[eyedee]

I have just bought a 2 x 8" sub box, and a pair of Kenwood 6.5" Dual Mags. I have a set of 5 x 7 JBL's in the rears at the moment and I am trying to decide which amplifier type I should buy to power them all? My system comprises of:

2 x 8" 200Watt (100Watt x 2) Sub Box
2 x 6.5" Kenwood Dual Mags rated as 220Watts each
x x 5 x JBL rated at 55 Watts each
Sony Headunit with dedicated SUB out, Front Aux and Rear Aux
1.0 Farad Capacitor

I would like to purchase just one amp to power them all and would like to get as much low bass out of the subs as possible, which I think is best done by 'bridging' the signals as MONO - what do you all think? Which Amp type should I be searching for and how should I bridge the channels to get the best out of my subs?

All advice very much welcomed! :D

[babz_audio]

what subs are they?

you would be better ff getting a 4 channel amp to power the 2 subs and rear speakers and then get your headunit to power up your front speakers...abit of fiddling around with amp settings and you will be able to listen to it mellow and loud without giving a bad signal to your fronts...

[eyedee]

Hi mate,

The subs are from a company called D-Class who deal mainly in manufacturing and supplying speakers to clubs, pubs, gigs etc. But they make a small selection of well priced in car subs on the side.

Ive ran my front components off an amplifier at the rear o my car for years and never suffered any loss of signal or interferance before? In fact, the only time I did suffer interferance it was when the front speakers were hooked up to a kenwood CD head unit in a Reanult Megane back in the 90's!

I dont think a stereo would provide enough power to make full use of the front speakers without an amplifier.

You any good at bridging amps? Theres about 3 or 4 methods and I dont know which is best?!?

Cheers :wave

[shaunwil]

Power readings are always a bit of a gamble anyway. It all depends on how much you want to spend. I have a DLS A4 Ultimate sat in the cupboard i may be looking at selling for the right price. They are £850 new, looking for at least £350. Its only 4 x 50w rms but is absolutely massive and extremely powerful, will easily run what you are looking at.

Will help towards the uprated injectors and fuel pump going in next week !

Shaun

[eyedee]

Had a search online and it does look like a cracking amp! Its a bit out of my price range unfortunately, as I just had mu engine rebuilt. :( It does look nice tho... hmm

[eyedee]

Would anyone know if its possible to run 2 x subs, off of a single SUB specific MONO output, from a head unit via a single 500W channel amplifier?

The amp accepts positive and negative auxilary inputs (although the headunit only offers a single aux output to use) and outputs a single left and right speaker connection.

Anyone any ideas how I could get the two subs running off of the single output and via the amp as outlined above? :confused:

[FD3SNuttah]

ou can do it mate, its not difficult. what you have to do is dedicate one channel to your subs and bridge them in parrallel but be warned you need a decent amp to do this otherwise your gonna have a smoke machine in your boot!!

Try looking at genesis amps,. at the factory they test the amp and provide you with a "true" figure of what it runs. Im pretty sure they do a five channel amp which can do everything you need it to do.

for reference look on the talkaudio forum (google it cos i cant remember the address) they are a clever bunch on there and can point you in the right direction pertaining to amp choice and trade offs maybe you can pick up something from thier for sale section.

if needs be i can draw a wiring diagram on how to wire your subs in parallel later on when i get home.. in the meantime you should check out 5 channel amps - look on car audio direct they seem to be the most competative on the net at the minute..

Personally i run two amps a mono block PG with 2 12" focal subs and a legacy four channel powering the four 6x9's two in the front doors -- (had to use an angle grinder for those bad boys lol) and two on the parcel shelf in my 323F.

One thing to remember is to get a DECENT wiring kit. the wires are often over looked and are the cause of failure in most car stereo systems, a good analogy is that the wires are the "viens" of your system.

[munkay]

its all a matter of ohmage when it comes to bridging 2 subs onto a mono amp,

any decent mono amp will run @ 2ohm or less (the lower the better)

usually in car subs are 4 ohm but you can get rather 2/4/6/8 ohm subs you can also get dvc (dual voice coil) subs which have 2 coils which make it more complicated,


most cheap subs run as single 4ohm

bridging 2 of these in parrallel will give you



1/4+1/4 =1/2 inversed = 2ohm resistance
bridging 2 in serial will give you 8ohms (not good)

[shaunwil]

You can run them in series as well, so that the ohm is added instead of devided. Have a look for any directed amps. I have a directed 600d, good for 600w rms at 1 ohm. Would run 3 x 12 dual coil subs happily. 2 subs where the best (with 2 coils in each sub), running at 1 ohm !

If you want it just for subs then go for a class d amp, they are very effiecent and powferful. They aren't made for higher range tones because they have less filters in them.

try these:

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&category=18796&item=5774964438&rd=1

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&category=18797&item=5774114029&rd=1

Shaun