diysmartdeep21 said:
Maybe it will be stable, maybe it won't. While the PSU has something to do with this, it will mainly depend on what chip you use to build it with, what components you use, how you wire it and what loudspeakers you connect it to.
2*22 volts is not really enough to get you 60 watts. Something like 2*28 is more likely to produce what you need.
Supply caps looks completely enough.
Rune
PS. Texas is a part of this forum where slightly offensive posts get moved. look here:Texas
diysmartdeep21 said:
You want to drive big woofers, so you should not compromise on the PSU.
You would be better using a 2x22v to 2x24v trafo at around 400VA.
Anyway, besides this, you are making lots of questions while the answer for most are on the datasheet, and you can also search the forum.
And I'm not Mr. Tube.
well RUNEBIVRIN well actually I wan to use the LM4780 chip so and as 22-0-22 volts are the output from the transformer then after rectification it goes to arround 31.68volts and this will be given to the chip
so I think this is much better and stable operating voltage for the LM4780 and if we use about 28-0-28 then after rectification it goes to 40.32 and with peak to peak it will go to 80.64 V which is very very close to the max voltage so ive chosen 32volts at the chip input so that it matches the requirement...
Thank you very much
so I think this is much better and stable operating voltage for the LM4780 and if we use about 28-0-28 then after rectification it goes to 40.32 and with peak to peak it will go to 80.64 V which is very very close to the max voltage so ive chosen 32volts at the chip input so that it matches the requirement...
Thank you very much
Either work your way backwards from the desired power or forward from available transformers.
If you want 60W in 8ohms you'll need +-35V. If you use the standard single rectifier bridge, you'll need (35+1.5)/sqrt(2) = 25VAC. Of course you'll need 2*25V.
The chip is spec'd for this, so should be OK with sufficient cooling. You might want to look into paralleling the two amplifiers in the chip for better low impedance handling.
If what you have is a 2*22V 120VA transformer, by all means use it. You'll get +-30VDC, which will give you 45W output. There won't be an audible difference. If you want to run continously on full power you need one transformer per channel, as it will draw around 90W/channel then.
Rune
If you want 60W in 8ohms you'll need +-35V. If you use the standard single rectifier bridge, you'll need (35+1.5)/sqrt(2) = 25VAC. Of course you'll need 2*25V.
The chip is spec'd for this, so should be OK with sufficient cooling. You might want to look into paralleling the two amplifiers in the chip for better low impedance handling.
If what you have is a 2*22V 120VA transformer, by all means use it. You'll get +-30VDC, which will give you 45W output. There won't be an audible difference. If you want to run continously on full power you need one transformer per channel, as it will draw around 90W/channel then.
Rune
Without getting into an argument about how an oversized VA transformer may sound better, 120VA will be fine for 22-0-22 one channel, just about barely adequate for two channels if you don't crank it. A good rule of thumb is transformer VA = 2x amp power. As 22-0-22 will give you 45W.........
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.