Hello to all
I have a fully functional soundstream goliath xxx6500 amplifier.
My question is pure curiosity.
We know very well that this is an amplifier that has a good yield at 16volt, much less at 12 volts.
Unfortunately, in my car I have a 12volt power supply system and I do not foresee the installation of 14 or 16 volt batteries (not even a larger alternator).
Generally, the amp is fine, but I would like to know if there is a safe and proven way to modify this amplifier to make it good even at 12volt.
I can say with certainty that he uses a regulated type power supply and the regulation is maintained by R41-42-44-45 resistors that reach the pwm card.
Logically, I think a higher rail voltage is needed to make this amplifier better (in fact, I think that's what actually happens when you connect this to 14 or 16volt).
This PWM card is very special, because it manages the power transformers separately from the service transformer (the smallest), in fact, has 2 separate PWMs (2 x TL494) and also for the service transformer a regulated type power supply is adopted.
The fact of having 2 separate PWMs allows me to make changes to the rail voltages without affecting in the least all the other service voltages.
I believe that gradually increasing the value of the resistors we could obtain a higher (even slightly) rail voltage that allows us to obtain results superior to HUMAN battery voltages.
I've also attached link for amplifier schematic download here:
LANZAR OPTI4000D SCH Service Manual download, schematics, eeprom, repair info for electronics experts
Is for a lanzar opti4000 that use the same board.
What do you think?
I have a fully functional soundstream goliath xxx6500 amplifier.
My question is pure curiosity.
We know very well that this is an amplifier that has a good yield at 16volt, much less at 12 volts.
Unfortunately, in my car I have a 12volt power supply system and I do not foresee the installation of 14 or 16 volt batteries (not even a larger alternator).
Generally, the amp is fine, but I would like to know if there is a safe and proven way to modify this amplifier to make it good even at 12volt.
I can say with certainty that he uses a regulated type power supply and the regulation is maintained by R41-42-44-45 resistors that reach the pwm card.
Logically, I think a higher rail voltage is needed to make this amplifier better (in fact, I think that's what actually happens when you connect this to 14 or 16volt).
This PWM card is very special, because it manages the power transformers separately from the service transformer (the smallest), in fact, has 2 separate PWMs (2 x TL494) and also for the service transformer a regulated type power supply is adopted.
The fact of having 2 separate PWMs allows me to make changes to the rail voltages without affecting in the least all the other service voltages.
I believe that gradually increasing the value of the resistors we could obtain a higher (even slightly) rail voltage that allows us to obtain results superior to HUMAN battery voltages.
I've also attached link for amplifier schematic download here:
LANZAR OPTI4000D SCH Service Manual download, schematics, eeprom, repair info for electronics experts
Is for a lanzar opti4000 that use the same board.
What do you think?
This has a switch mode power supply and at 12 volts will draw more current from your battery as it tries to produce the high voltages required by the output stage. At 18volts, it is pretty close to the limit for the power supply specification as it is rated for up to 14volts supply.
I suspect it does not perform as well on 12volts because of voltage drop in the supply cables from the battery supplying it.
I suspect it does not perform as well on 12volts because of voltage drop in the supply cables from the battery supplying it.
Whatever it is the reason of the low yield at 12volt, it is a known thing that this amplifier makes a lot more to 16volt, in fact its maximum power is declared to 16volt, while 12 volts sleeps.
My main suspicion falls on the rail, which is "xxxV" to 16Volt of battery, while at 12 volts of battery the rail drops a lot (probably).
I had brought feedback resistors of the power supply circuit into play, because in the past, I've already done some experiments on other amplifiers that worked the same way, and gradually increasing those same resistors, I got a higher rail, just for fear of causing damage and for security reasons, I restored everything to normal and avoided making further experiments.
I have two of these amps I just bought because I'm thinking about tackling RE the dlm card in these amps. Anyhow, I'm not likely to get working on them until this winter, but my understanding is the power supply is very loosely regulated. In fact, SS said they were unregulated, but we know that there have to be some limits in place. Like I said, I haven't spent any time working with it yet, but my guess is that there is a upper rail voltage limit and the duty cycle runs at max until it approaches the upper limit, then it decreased duty cycle to keep the rail voltage in check. It seems a lot of "unregulated" amps seem to function somewhat similar to what I describe, and it means more input voltage equals more rail voltage until it approaches the limit where the pwm reduced duty cycle.
The point is, a power supply designed similar to what I describe is not going to respond as you are wanting to feedback changes. You need a ps that is very tightly regulated in order to be able to make useful changes just in feedback. Meaning if a switcher has a target voltage of +/-50v on the rails and the xformer turn ratio is such that with 12v supply and 24% duty cycle your trails are in range. Many car audio amps controllers have a range of 0-49% duty cycle. Obviously this is hypothetical, in such a case you would be able to move the rails quite a bit with only feedback changes. In the case of an amp with very loose regulation which I believe these SS amps to be, the only way to get those same results is going to be to add a few turns on the secondaries of the power transformers.
Personally I've also wondered why the manufacturer chose to not just wind the transformers for 12-14v from the get go. My guess on that is two fold - at 16v input your are probably close to the upper limits of many components in the amp and the thought may be that it will only get run at 16v for competition level use, in which case it doesn't have to be able to run for an unlimited amount of time at or near design limits. My other thought is just that it's too much current for the smps to reliably run with 12v supply.
I'm curious what you come up with, so keep us posted!
Thanks,
Jason
The point is, a power supply designed similar to what I describe is not going to respond as you are wanting to feedback changes. You need a ps that is very tightly regulated in order to be able to make useful changes just in feedback. Meaning if a switcher has a target voltage of +/-50v on the rails and the xformer turn ratio is such that with 12v supply and 24% duty cycle your trails are in range. Many car audio amps controllers have a range of 0-49% duty cycle. Obviously this is hypothetical, in such a case you would be able to move the rails quite a bit with only feedback changes. In the case of an amp with very loose regulation which I believe these SS amps to be, the only way to get those same results is going to be to add a few turns on the secondaries of the power transformers.
Personally I've also wondered why the manufacturer chose to not just wind the transformers for 12-14v from the get go. My guess on that is two fold - at 16v input your are probably close to the upper limits of many components in the amp and the thought may be that it will only get run at 16v for competition level use, in which case it doesn't have to be able to run for an unlimited amount of time at or near design limits. My other thought is just that it's too much current for the smps to reliably run with 12v supply.
I'm curious what you come up with, so keep us posted!
Thanks,
Jason
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What's the difference in 12v and 16v power?
If the power supply is reaching full duty cycle at 12v before making the desired power, you will have to add secondary windings.
It may be easier to reduce the rail voltage and use a lower impedance load.
As was stated above, reliability may suffer if the amp is asked to produce more power for extended periods of time.
If the power supply is reaching full duty cycle at 12v before making the desired power, you will have to add secondary windings.
It may be easier to reduce the rail voltage and use a lower impedance load.
As was stated above, reliability may suffer if the amp is asked to produce more power for extended periods of time.
Perry, if I recall correctly the amp does about 4kw rms at normal ~13.5v input. At 16v they will reliably hit or exceed their 6.5kW Rms that they were rated for. It seems that somewhere on the internet I saw it dynoed to show the difference. It was "designed" to run on up to 16v, but I think it's highly unlikely that the manufacturer meant for them to be run like that for everyday use.
I have a pair of ppi pdx-10ks from the same erra and probably the same oem. They to are rated up to 16v input. Those ones don't have a dlm card though, so I'm getting lots of boards to reverse this winter ��
I have a pair of ppi pdx-10ks from the same erra and probably the same oem. They to are rated up to 16v input. Those ones don't have a dlm card though, so I'm getting lots of boards to reverse this winter ��
You're probably looking at 800+ amps of current to get that power at 12v. Even if the batteries can supply it, it will take the alternator much longer to return that energy to the batteries and pretty soon, you're operating at even less than 12v. It doesn't seem practical without a significant upgrade to the electrical system.
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