LD DSP45K bridge mode - seeing 1/2 impedance?
I'm using a DSP45K in bridge mode to move 1100W 4ohm subwoofer.
I just want to know if electrically is seeing a 2ohm resistence or a 4ohm resistance.
As it's 4 channels amp. And, in bridge mode, 1 and 2 outputs are sent through +1-2 poles on 1 conector.
Or each of the 4 channels are working seeing a 4ohm resistance?
I link the manual:
https://adamhall.s3.amazonaws.com/m...ems_Bedienungsanleitung_EN_DE_FR_ES_PL_IT.pdf
thanks a lot for your help
I'm using a DSP45K in bridge mode to move 1100W 4ohm subwoofer.
I just want to know if electrically is seeing a 2ohm resistence or a 4ohm resistance.
As it's 4 channels amp. And, in bridge mode, 1 and 2 outputs are sent through +1-2 poles on 1 conector.
Or each of the 4 channels are working seeing a 4ohm resistance?
I link the manual:
https://adamhall.s3.amazonaws.com/m...ems_Bedienungsanleitung_EN_DE_FR_ES_PL_IT.pdf
thanks a lot for your help
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Is this a DVC sub or a single voice coil?
When a 4ohm voice coil is connected to a bridged 2ch amp each channel of that amp "see's" 1/2 of that load or 2ohms.
If you have a DVC sub and each coil is connected to it's own bridged amplifer pair that is fine, but if the sub has a single voice coil you can only connect it to a single bridged pair, you cannot connect both bridged pair to the same voice coil... that essentially shorts the amp outputs together which is very bad... may cause the amp to self destruct.
When a 4ohm voice coil is connected to a bridged 2ch amp each channel of that amp "see's" 1/2 of that load or 2ohms.
If you have a DVC sub and each coil is connected to it's own bridged amplifer pair that is fine, but if the sub has a single voice coil you can only connect it to a single bridged pair, you cannot connect both bridged pair to the same voice coil... that essentially shorts the amp outputs together which is very bad... may cause the amp to self destruct.
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When you bridge an amplifier, each half sees half of the load impedance. So if you bridge into 8ohm, you get the power output from both channels seeing 4ohm.
In my opinion, it would be better stop using the amplifier in bridged mode. It's 2400w/ch when bridged into 4ohm, or 1200w/ch into 4ohm not bridged. This is because the amplifier doesn't like to drive 2ohm - there is less power there than at 2.7ohm, which indicates the amplifier is running out of current capability. It will also become very hot if you push the volume.
The difference between 2400w and 1200w is 3dB, but the amplifier is having to work very hard when producing 2400w, and the speaker is also going to show signs of power compression, so you might find you only get 1 or 2dB more output long-term.
When it comes to running 2ohm, test it! Pick a really warm day, put the amplifier in the sun, and turn it up. If the amplifier runs fine at high power, then fair enough, keep it running at 4ohm bridged (2ohm on each channel). Many amplifiers will shut down under that treatment, and if yours does that, it's time to go back to 4ohm on each channel.
Chris
In my opinion, it would be better stop using the amplifier in bridged mode. It's 2400w/ch when bridged into 4ohm, or 1200w/ch into 4ohm not bridged. This is because the amplifier doesn't like to drive 2ohm - there is less power there than at 2.7ohm, which indicates the amplifier is running out of current capability. It will also become very hot if you push the volume.
The difference between 2400w and 1200w is 3dB, but the amplifier is having to work very hard when producing 2400w, and the speaker is also going to show signs of power compression, so you might find you only get 1 or 2dB more output long-term.
When it comes to running 2ohm, test it! Pick a really warm day, put the amplifier in the sun, and turn it up. If the amplifier runs fine at high power, then fair enough, keep it running at 4ohm bridged (2ohm on each channel). Many amplifiers will shut down under that treatment, and if yours does that, it's time to go back to 4ohm on each channel.
Chris
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