how to upgrade amplifier for more power?

[DigiSoft]

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?

[bob91343]

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.

[DigiSoft]

Originally Posted by bob91343

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.

But is it possible to increase output power without increasing 30V rail?

[wahab]

Originally Posted by DigiSoft

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.)....

[bob91343]

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?

[DigiSoft]

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 ?

[bob91343]

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.

[trd1587]

So In conclusion....The 30v Rail doesn't remove the clics and pops on an old 78 RPM Thermoplastic?

[bob91343]

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.

[DigiSoft]

It uses +30 0 -30 V so is it possible that it is around 50W?