Will I get more dB if I use 2- FOSI M01 sub amps to power the 2 voice coils in a dual coil subwoofer?
If the coils fed by one amp were wired in parallel, they would see the same voltage as they would if each had its own (identical) amp. So in that case no noticeable increase in dB. That is assuming the amp has sufficient ability to deliver current to two coils at the same time, anyway; if the amp were inadequate (for the coil/power) then sharing the load between two amps might see a fairly minor increase in dB, and possibly reduced distortion, less overheating etc.
If the coils fed by one amp were wired in series (e.g. perhaps the amp can't cope with low/parallel impedences) then yes, changing to one amp per coil would much more noticeably increase dB. The total power would be four times the original (one-amp+series-coils) configuration.
Though note that the increase in dB with an increase in power doesn't follow a 1:1 relationship. Four times the power would actually only get you +6dB.
EDIT: though note that there might be practical problems with using dual amps, like getting the signals matching and perfectly in time; I haven't used bluetooth for this purpose but that would likely be a lot more tricky than if you're using the RCA input.
If the coils fed by one amp were wired in series (e.g. perhaps the amp can't cope with low/parallel impedences) then yes, changing to one amp per coil would much more noticeably increase dB. The total power would be four times the original (one-amp+series-coils) configuration.
Though note that the increase in dB with an increase in power doesn't follow a 1:1 relationship. Four times the power would actually only get you +6dB.
EDIT: though note that there might be practical problems with using dual amps, like getting the signals matching and perfectly in time; I haven't used bluetooth for this purpose but that would likely be a lot more tricky than if you're using the RCA input.
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EDIT: though note that there might be practical problems with using dual amps, like getting the signals matching and perfectly in time; I haven't used bluetooth for this purpose but that would likely be a lot more tricky than if you're using the RCA input.
Agreed.
Agreed.
Depends on what the impedance of the voice coils are.
The FOSI M01 24volt 4.5amp power supply current limits at 4 ohms.
It's ~75 watts at 8 ohms, but only 110w@4, less than +3dB gain (150 watts).
Don't know if the capacitors in the amp are rated for 36 volts, or how good the heat sink.
You may get more power with a 36volt voltage power supply than two amplifiers with 8 ohm coils.
The chip can put out ~80 watts into 3 ohms with a 24volt PSU, ~180 watts with a 36volt PSU.
More than +3dB.
Art
normal 4 layer voice coils are run in series inside the coil.
DVC is a market gimmick which puts taps to the coil layers.
Or simply puts taps at 2 layers.
You dont "get" more power from low impedance you " Use" more power
To put the same voltage to a lower impedance.
For more power you need more voltage.
If the amplifier has more voltage. You simply need more current depending on Impedance.
Basic ohms law.
For " DVC" just run series like a normal 4 layer.
Whatever power is needed, buy a amp that is that powerful.
4 ohms is already bad enough, yet alone marketing gimmicks from the 70's
Which would make 2 ohms some imaginary benefit.
The speaker will only move so far forward and back till it reaches distortion.
Max SPL is well defined. Making it suck up more current to do so isn't beneficial
Long story short, no 2 amps wont help SPL
and No 2 or 4 ohms wont change SPL.
Its a single speaker and the voltage limit before distortion is the same.
How much power that is wasted or not wasted wont change the SPL either.
You add more cone area to gain higher SPL, Or use 2x speakers not 1
Making the load more difficult to drive. Does not get more power.
It uses more power.
DVC is a market gimmick which puts taps to the coil layers.
Or simply puts taps at 2 layers.
You dont "get" more power from low impedance you " Use" more power
To put the same voltage to a lower impedance.
For more power you need more voltage.
If the amplifier has more voltage. You simply need more current depending on Impedance.
Basic ohms law.
For " DVC" just run series like a normal 4 layer.
Whatever power is needed, buy a amp that is that powerful.
4 ohms is already bad enough, yet alone marketing gimmicks from the 70's
Which would make 2 ohms some imaginary benefit.
The speaker will only move so far forward and back till it reaches distortion.
Max SPL is well defined. Making it suck up more current to do so isn't beneficial
Long story short, no 2 amps wont help SPL
and No 2 or 4 ohms wont change SPL.
Its a single speaker and the voltage limit before distortion is the same.
How much power that is wasted or not wasted wont change the SPL either.
You add more cone area to gain higher SPL, Or use 2x speakers not 1
Making the load more difficult to drive. Does not get more power.
It uses more power.