amp dilema

[desmond937]

but then the amp can support 75wRMS x 2 at 4ohm, written on the box, although is 4 channel amp. written there bridgeable also. should be able to pump this small 6.5" component speakers rite? cos i'm not using it to pump woofer. it'll be damn hot if i do so? hmm......cos i found this 4 channel amp i bought not utilize the 4 channel, the 2 channel connect to the back speakers did not utilize its power. i sit at the back rite, the sound from the back speakers is just giving some "add up" sound only.from back, the front speakers produce music noticeably than the rear. so i tot of bridge this 4 channel amp to 2 channel by just connect the component set at the front. hmm....then the rear just connect to the HU, make it got sound then can d.
did u guys all also never care bout the rear speakers? also just connect to the HU only?

btw, how do u guys add fan to an amp?

 

[kyheng]

But if you bridge the amp, your speakers power still higher than your amp..
Regarding to the sound on back, I think you have to increase the gain abit and see how.
Add fan, very simple, go to Low Yat plaza, buy a PC fan(12V), here is the tricky part, your amp have +ve, rem and ground/earth right? The Rem is +ve also, and the fan got 2 terminal +ve, -ve. So the +ve you can either connect to amp's +ve(run all the time) or Rem(when HU is on) then -ve to ground.

 

[Zenn]

i plan to just bridge this 4 channel amp, so i can get 75wRMS x 2 to power just the front new component set. the back speakers just connect straight from HU.

yes i support u 100% hehe, i prefer this way also, rear speakers should only give some rear fill ambience sound, most of the sound should come from the front.

 

[howiechoo]

4ch amp bridged for comp set not really hot la...and ii dun think any comp set can perform more than it's power rating..maybe just 65-70RMS it already distort? and also dun think he will turn so loud all the time..most probably 50-75% if he are cruising..if he SPL, then mah usually <2 hour..should be no prob at all.

 

[desmond937]

oh, so generally is not a problem to do so rite? hmm, then i can start to save money now to get a branded component set. hmm, the problem i'm concern is when i connect the back speakers, which give 50wRMS one, is a coaxials speakers, will however got not enough power to run this speakers. so worried the result come out even worst, cos back speakers give some noise due to not enough power from HU (45wx4). any comment? right now the back speakers also din give bass, maybe i cant hear it due to the sub from my boot, just hear it giving some vocal sound.

kyheng, thanks for teaching me to connect the fan, i want to arrange as much fan as can to put on top on the amp, hehe.....make it cool la. same connection for each fan rite?

 

[desmond937]

got a question again, i'm quite satisfy the tuning of my setup now, but then becos of the hissing sound, i like to decrease the amp gain, so this hissing sound will gone, hopefully. can i just turn the amp gain knob abit down and not adjusting the rest?

 

[kyheng]

Should be no problem..

 

[desmond937]

whats that gain for already? to increase signal if increase the gain? decrease signal means decrease quality of the sound d rite?

 

[kyheng]

Is the amp so called volume control.

 

[Zenn]

the gain is to compensate for the strength of signal from the HU, if Hu output is low (less than 4v) u will turn up the amp gain, if it is high (4v and above) can keep at minimum gain, but all depends la on the amp itself, some also cant take more than 2v.....hehe

 

[desmond937]

HU produce so little voltage? wat bout those HU that written 50w x 4? how many volt they produce?
mine is just 45w x 4, 5 years back liao lo......haha......dun wanna change new HU, scare thief la.

 

[kyheng]

Hello, you get the V(volt) and w(watt) words mixed up already. Like house eletronics, it state there 240V3000W, this is the spec for an oven

 

[desmond937]

kyheng, i know the difference between Volt and Watts, i just want to know like HU with 45watts x 4 gives how many volts? usually?

 

[kyheng]

Well, sorry, thought you don't know.... If your HU manual is still there, you can turn to almost last page, then you will see the overall specs. For Pioneer, normal range will be at 2.2V max, that's the max volume or almost max volume that you turn the HU will produce that power. SO if 50% then the voltage will be around 1.1V.

 

[desmond937]

wah, so little only, now only i know HU uses so little volt. if in this case, i think i cant lower the gain too much, else theres no sound produce rite?

if let say i bridged the 4 channel amp already, where should i connect the RCA? the front channel or rear? or each at both channel?and then if i bridge the 4 channel amp to support my component, my electronic XO rear channel will be useless already rite?cos i plan to connect the rear coaxials spk to HU. i still wonder how it sounds when bridge 4 channel to 2, then support the component. i guess i'm the only guy who did this to waste a 4 channel amp! sigh....any comment?

 

[desmond937]

today out of curiosity, i read my amp. manual again, to be suprise, written there "4ohm bridged mono, all channels driven = 75wRMS x 2". this means after bridged cannot play component speakers already lo is it?

 

[cacin]

Bro, I would suggest that you refer back to your amp manual. It should tell you how to achieve what you want/need.

If you bridged the 4ch amp, it means that it only can power 2 channel now. What you connect to the channel, I don't know. Depends on you la..

 

[desmond937]

so u mean even i bridged any 4 channel amp, so it became 2 channel, is not in mono rite? that means can use either component or woofer rite? pls clarify, need help. wanna plane my future upgrade la....:)

 

[Zenn]

kyheng, i know the difference between Volt and Watts, i just want to know like HU with 45watts x 4 gives how many volts? usually?

the 45Wx4 is the speaker output of the HU from its tiny inbuilt amp, usually around 12-15W rms only, so this concerns u if u are driving speaker direct from HU. if u are using amps (rca pre-out) then only u think of the volts which is the strength of the signal from your Hu to amp through the RCAs.

 

[Zenn]

wah, so little only, now only i know HU uses so little volt. if in this case, i think i cant lower the gain too much, else theres no sound produce rite?

if let say i bridged the 4 channel amp already, where should i connect the RCA? the front channel or rear? or each at both channel?and then if i bridge the 4 channel amp to support my component, my electronic XO rear channel will be useless already rite?cos i plan to connect the rear coaxials spk to HU. i still wonder how it sounds when bridge 4 channel to 2, then support the component. i guess i'm the only guy who did this to waste a 4 channel amp! sigh....any comment?

if u bridge the 4ch to become a 2ch, then the inputs depend on the amp manufacturer itself. some allow single pair rca input, some dont, then u have to use a pair of Y-cables, look like normal rca just it has one input & 2 outputs)

if your rears wont be powered by an amp then u dont need to connect anything to your e-cross rear output, leave it like that. when u bridge the 4ch into 2 theoretically u will get double the power so the sound in some cases will be much better, like more bass.