I'm probably wrong, but if you have an amp with higher power ratings then the highs you're hooking it up to, couldn't you just turn the gain down and it'd be giving it less power and all would be fine?
Replies (2)
ttocs on 12/28/2005 11:05:13
It is easier to blow a speaker from too little power, then it is with too much. You are correct that with proper adjustment(gain and volume) to hook an amp to with a higher power rating. If it says 500 watts that doesn't mean it has 500 watts comming out of it all the time.
swez on 12/28/2005 12:24:09
Agreed!
But there are some cases; like when a HU has a 4 volt output and the sub amp has a max input of 4 volts, the gains are already set to minimal sensitivity and will only amplify to the signal level the amp receives.
To get around that, we use an input attenuator. This device will drop the HU voltage the amp gets by a give amount, based on the resistor value. Attenuators are generally marked in units of dB reduction. They can be fixed or variable. (a light dimmer switch for example)
Example: A -3dB attenuator circuit will drop the HU voltage by 50%. Now, we have a 2 volt input signal and the amps power to subs will be decreased by half.
FYI: Small format speakers can have very high sensitivity ratings. A spec of 90 dB SPL @1 Watt/1 Meter is pretty common. This means with as little as 16 watts of input power, we get about 102dB from them. That's why many guys can run front and rear (full range) speakers off a good Aftermarket HU. (18-25 watts/channel are common)
Subs, on the other hand, tend to have lower sensitivity ratings in the mid- 80's dB SPL. (Yes, there are subs out there that are well over 90dB at 1w/1m. But that is not the norm). Here, it takes a bit more power (Watts) to get subs up to the same SPL levels. A sub with a sensitivity rating of say 85dB SPL @ 1w/1m, will need almost 80 watts of input power to hit that 102dB SPL. That's where a larger amp comes into play for our subs.
Finally, the key to a clean and potent sound system is having enough amping power at all times, to keep the amps from running in the heavy clipping mode. (high distortion) To accomplish this, we really have to map out a strategy in a logical and knowledgable way. It takes a bit of time to learn the steps, but it's not rocket science and CK forum has some very talented guys to walk folks through the steps.
Just read other postings and see how others have achieved their goals and follow their lead. The DIY section of this forum has lots of useful information to get you up to speed as well.
Swez
Replies (2)
ttocs on 12/28/2005 11:05:13
It is easier to blow a speaker from too little power, then it is with too much. You are correct that with proper adjustment(gain and volume) to hook an amp to with a higher power rating. If it says 500 watts that doesn't mean it has 500 watts comming out of it all the time.
swez on 12/28/2005 12:24:09
Agreed!
But there are some cases; like when a HU has a 4 volt output and the sub amp has a max input of 4 volts, the gains are already set to minimal sensitivity and will only amplify to the signal level the amp receives.
To get around that, we use an input attenuator. This device will drop the HU voltage the amp gets by a give amount, based on the resistor value. Attenuators are generally marked in units of dB reduction. They can be fixed or variable. (a light dimmer switch for example)
Example: A -3dB attenuator circuit will drop the HU voltage by 50%. Now, we have a 2 volt input signal and the amps power to subs will be decreased by half.
FYI: Small format speakers can have very high sensitivity ratings. A spec of 90 dB SPL @1 Watt/1 Meter is pretty common. This means with as little as 16 watts of input power, we get about 102dB from them. That's why many guys can run front and rear (full range) speakers off a good Aftermarket HU. (18-25 watts/channel are common)
Subs, on the other hand, tend to have lower sensitivity ratings in the mid- 80's dB SPL. (Yes, there are subs out there that are well over 90dB at 1w/1m. But that is not the norm). Here, it takes a bit more power (Watts) to get subs up to the same SPL levels. A sub with a sensitivity rating of say 85dB SPL @ 1w/1m, will need almost 80 watts of input power to hit that 102dB SPL. That's where a larger amp comes into play for our subs.
Finally, the key to a clean and potent sound system is having enough amping power at all times, to keep the amps from running in the heavy clipping mode. (high distortion) To accomplish this, we really have to map out a strategy in a logical and knowledgable way. It takes a bit of time to learn the steps, but it's not rocket science and CK forum has some very talented guys to walk folks through the steps.
Just read other postings and see how others have achieved their goals and follow their lead. The DIY section of this forum has lots of useful information to get you up to speed as well.
Swez
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