I have car amplifier that uses TIP2955 + TIP3055 for one channel.
It has 30V DC power supply.
Is it somehow possible to put parallel transistors to TIP2955 + TIP3055 and get more power? Or I also must increase the voltage?
It has 30V DC power supply.
Is it somehow possible to put parallel transistors to TIP2955 + TIP3055 and get more power? Or I also must increase the voltage?
Parallel transistors will increase the current handling of the output stage. But you still need enough current to drive them, and enough heat sink to cool them. And you need a bigger power supply to operate them. It's a major redesign.
I wouldn't bother. Get or build a more powerful amplifier if that's what you want.
I wouldn't bother. Get or build a more powerful amplifier if that's what you want.
But is it possible to increase output power without increasing 30V rail?
No, whatever the case, you ll be stuck with the power
supply limited power, whether you use same voltage and lower
impedance speaker or raise the supply voltage...
If it s a car amp, better to find another one, they are cheap
when used ( i did found a pionner gm2200 for 15 euros.)....
If you don't increase the voltage you are relying on more current to get higher output power. If you want more current you must use a lower speaker impedance; the amplifier is probably designed for 8 Ohms so you will need to load it with, say, 4 Ohms to get more power. But it might deliver that much as it stands.
I will explain about power and voltage. If you have a 30 Volt power supply, single ended, that is 15 volts either side of zero at the speaker. The transistors have some voltage drop, let's say one volt, so you have 14 volts either side of zero. So the highest peak of sine wave you can drive is 14 volts peak, or about 10 volts rms. With 10 volts rms you square that and divide by speaker impedance; that gives about 12 Watts into 8 Ohms, or 24 Watts into 4 Ohms.
Paralleling transistors won't change Ohm's law. The output power is limited by the rail voltage and the current the transistors can handle. If you have 10 Volts into 8 Ohms you are asking the transistors to pass about 1.25A rms (combined) or say 1.7 A peak.
Do you follow my explanation?
I will explain about power and voltage. If you have a 30 Volt power supply, single ended, that is 15 volts either side of zero at the speaker. The transistors have some voltage drop, let's say one volt, so you have 14 volts either side of zero. So the highest peak of sine wave you can drive is 14 volts peak, or about 10 volts rms. With 10 volts rms you square that and divide by speaker impedance; that gives about 12 Watts into 8 Ohms, or 24 Watts into 4 Ohms.
Paralleling transistors won't change Ohm's law. The output power is limited by the rail voltage and the current the transistors can handle. If you have 10 Volts into 8 Ohms you are asking the transistors to pass about 1.25A rms (combined) or say 1.7 A peak.
Do you follow my explanation?
So the maximum that I can get from 30V is 30W amplifier?
Because TIP2955 + TIP3055 makes 30W amplifier right?
This amp is really big and heavy and it says it is 2 x 100W. It also have converter 12 to 30V. So this amp is actually 2 x 30W and not 2 x 100W?
Then how they make 4x50W in car CD player and I have that big amp that only delivers 2x30W with that many components ?
Because TIP2955 + TIP3055 makes 30W amplifier right?
This amp is really big and heavy and it says it is 2 x 100W. It also have converter 12 to 30V. So this amp is actually 2 x 30W and not 2 x 100W?
Then how they make 4x50W in car CD player and I have that big amp that only delivers 2x30W with that many components ?
It depends on how it's specified and designed. With a single 30V supply you can get 12 Watts into 8 Ohms and 24 Watts into 4 Ohms if I am figuring it correctly. If you connect two 4 Ohm speakers it's possible to get twice that, with a 2 Ohm load, or 48 Watts.
I don't know what you have there. Maybe it has two 30 Volt supplies, one negative and one positive. If so, you are working with 60 Volts and will get four times the power, nearly 50 Watts into 8 Ohms. Or 100 Watts into 4 Ohms.
I may have screwed up these calculations. I just came in from the living room where I am working on my setup, and my hands hurt and I am mentally exhausted from all the dumb things I had to do. I used an old Kenwood receiver just for its phono preamplifier so I can now use two turntables without a special switch. Then I had problems with the head shell and had to heat the mounting to correct a set the plastic took over the years that caused one channel to fail. Then I lost the ball at the base of the turntable bearing. By the time I found that, I had records all over the floor and was losing patience with the job. Once everything started to work I had to listen to a few old 78 rpm records to enjoy the system.
I don't know what you have there. Maybe it has two 30 Volt supplies, one negative and one positive. If so, you are working with 60 Volts and will get four times the power, nearly 50 Watts into 8 Ohms. Or 100 Watts into 4 Ohms.
I may have screwed up these calculations. I just came in from the living room where I am working on my setup, and my hands hurt and I am mentally exhausted from all the dumb things I had to do. I used an old Kenwood receiver just for its phono preamplifier so I can now use two turntables without a special switch. Then I had problems with the head shell and had to heat the mounting to correct a set the plastic took over the years that caused one channel to fail. Then I lost the ball at the base of the turntable bearing. By the time I found that, I had records all over the floor and was losing patience with the job. Once everything started to work I had to listen to a few old 78 rpm records to enjoy the system.
So In conclusion....The 30v Rail doesn't remove the clics and pops on an old 78 RPM Thermoplastic?
Oy don't get me started on this. I think the head shell is nylon. It's a Grado arm and while it works well I think it's a terrible design from a maintenance viewpoint. I am considering returning it but I can't find the receipt from 1958.
yes, it should be close to 50W/8ohm , say 40W..
But remember that the power supply is implemented to
provide this power, so if you want to increase the audio output
power, you ll have to increase the supply power capability as well.
All in all , it doesn t worth it...
Ok but I see designs with 30V +- but with two pairs of TIP3055/TIP2955.
What is better with two pair then one pair of this transistors. The voltage is +-30V in both cases.
What is better with two pair then one pair of this transistors. The voltage is +-30V in both cases.
Adding a second pair will increase the reliabilty by a good margin,and as, it s a better implementation that also allow higher peak currents, provided the supply caps are big enough.
Generaly, they are no more than 3300 to 4700uF...
Well, it will increase by a watt or two, as the losses through
the transistors and their emitter resistors will be slightly less
with two pairs of power devices..
Main advantage will be a better reliability of the power amps.
There are a couple of ways to state the power output. First the RMS measurement
and in your amp it is probably ~ 30w RMS. 30w rms is ~50w peak or ~100w peak to peak. Saying the amp is 100w peak to peak makes you think you are geting a lot more than saying you are geting a 30W amp but it's the same. This assumes you
are running 8 ohm speakers. When you go to 4 ohm speakers you get almost 2X the
power. But no you can't modify your amp for higher power you would need a power
supply section with more current and voltage. Then need to add more or stronger output devices and maby a couple of more changes.
and in your amp it is probably ~ 30w RMS. 30w rms is ~50w peak or ~100w peak to peak. Saying the amp is 100w peak to peak makes you think you are geting a lot more than saying you are geting a 30W amp but it's the same. This assumes you
are running 8 ohm speakers. When you go to 4 ohm speakers you get almost 2X the
power. But no you can't modify your amp for higher power you would need a power
supply section with more current and voltage. Then need to add more or stronger output devices and maby a couple of more changes.
Yes I was thinking about that. And lets say I success increase the voltage to about 50V. But then I am not sure what will happen to the amplifier. Does the components are meant for that voltage. Maybe I'll need to change resistors in power amp? I don't know.
car amp?
If it is a car amp you are trying to upgrade, they are often specified at 1 ohm output, which doesn't require much power supply voltage to get rediculous watts, but leaves you very few choices of quality speakers at that impedence. If it a house current driven amp, and you have spare heat sinks laying around (I do) look at the thread about the DPS-400 on the switching power supply forum to replace your power supply with something modern and tiny that would produce 50V rails. Look at your capacitor voltages if they need upgrade, and expect to have to replace your predrivers transistors with something like TIP41C and TIP42C to stand the higher voltage. If your predriver circuitry is SOT package, use your extra heat sink to start over and build a new amp from one of the designs on this forum.
If it is a car amp you are trying to upgrade, they are often specified at 1 ohm output, which doesn't require much power supply voltage to get rediculous watts, but leaves you very few choices of quality speakers at that impedence. If it a house current driven amp, and you have spare heat sinks laying around (I do) look at the thread about the DPS-400 on the switching power supply forum to replace your power supply with something modern and tiny that would produce 50V rails. Look at your capacitor voltages if they need upgrade, and expect to have to replace your predrivers transistors with something like TIP41C and TIP42C to stand the higher voltage. If your predriver circuitry is SOT package, use your extra heat sink to start over and build a new amp from one of the designs on this forum.
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