First of all the meters are superfluous. Even peak meters lag a great deal. But the way to read yours is 0dB is 100 watts. Every 3dB up or down is twice or half the power. +6dB and 200 watts is just wrong. Sorry, but it is. +3dB is 200 watts. So your meters aren't even right. Like I said, superfluous. -10dB is 10 watts, at least they got that right.
You may wonder how it is that a 70 watt amp has 100W and 200W. This is because of all the different ways we measure power. If you look at your spec page https://www.technics.com/us/products/grand-class/stereo-integrated-amplifier-su-g700.html#specs you will see FTC output power with 70 and 140 watts at 8 and 4 ohms. Its that FTC thing we're concerned with. Amplifiers can put out really high power for a short time- peak power. They get hot being played loud and heat lowers their power output. FTC came along and said no more bragging peak power, you can only say what the amp can do continuously, and after being warmed up.
This is all important stuff to know because most guys just look at the number without really understanding what goes into that number. In reality you play your music at whatever level sounds good. The amp clips or doesn't, gets hot and shuts down or doesn't. If you can play it loud enough to be happy, it still sounds okay, its not getting too hot- and the meters aren't pegged a lot- then don't sweat it.
Its only if you're running it into clipping a lot- the meters are pegged a lot- that you would worry. In that case the answer is not more power. Your speakers are too inefficient. Because of the fact power doubles every 3dB then to go only 6dB louder you're going to need at least a 300 watt amp. The better answer is much more efficient speakers. Anything 95dB or higher and you'll have plenty of volume and no power worries at all.
You may wonder how it is that a 70 watt amp has 100W and 200W. This is because of all the different ways we measure power. If you look at your spec page https://www.technics.com/us/products/grand-class/stereo-integrated-amplifier-su-g700.html#specs you will see FTC output power with 70 and 140 watts at 8 and 4 ohms. Its that FTC thing we're concerned with. Amplifiers can put out really high power for a short time- peak power. They get hot being played loud and heat lowers their power output. FTC came along and said no more bragging peak power, you can only say what the amp can do continuously, and after being warmed up.
This is all important stuff to know because most guys just look at the number without really understanding what goes into that number. In reality you play your music at whatever level sounds good. The amp clips or doesn't, gets hot and shuts down or doesn't. If you can play it loud enough to be happy, it still sounds okay, its not getting too hot- and the meters aren't pegged a lot- then don't sweat it.
Its only if you're running it into clipping a lot- the meters are pegged a lot- that you would worry. In that case the answer is not more power. Your speakers are too inefficient. Because of the fact power doubles every 3dB then to go only 6dB louder you're going to need at least a 300 watt amp. The better answer is much more efficient speakers. Anything 95dB or higher and you'll have plenty of volume and no power worries at all.
