I have to think what to use as a front panel to have it nice, and what for the rest, top and side panels.
I did not try it to drive 2 ohm load in real life, but simulation shows this will be to much for two output pairs only. This really difficult question, some loudspeakers can dip as low as 2 ohm, but I don't have anything similar to try. This amplifier uses (in my case) PS regulator with overcurrent protection and, probably, will trip it if drove to hard on such load.
This is not so. This is an amp capable to drive 8 ohm to a bit more than 100 W, and almost double power on 4 ohm, and in some extend 3 ohm.
Your logic is a bit twisted. Let say, this amp can drive 8 ohm and able 4 ohm too. Because it can drive 4 ohm it should be able to drive 2 ohm, and as it is able to drive 2 ohm it should be able to drive 1 ohm, and so on.
What you mean, not current crippled?? This amp has an electronic fuse and thus it is current limited. It is not welding machine.
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Note I started my post with
My 8ohms capable amplifiers must be able to drive a 4r0 dummy/test load to near the maximum output voltage that is available into my rated 8ohms load.
I use the same criteria as posted in another Thread today.
16r/8r/4r and expect the power to be 60W/100W/180W
I do not expect an 8ohms rated amplifier to drive a 2ohms load.
I do expect a 4ohms rated amplifier to drive a 2ohms load.
That 3times power (180W/60W) going from 16r (double the rated load) to 4r(half the rated load) was my "old" standard for acceptable current delivery.
Having read R.Cordell, who recommends 180% of maximum rated power into half rated load impedance, I now adopt his standard for current delivery. It is slightly more onerous than the 3times rule.
Look at that 60/100/180. It too shows that 180% into half rated load.
To get to that 180%, the output current must be delivered with the output voltage dropping no more than 0.46dBV That is not an easy target to meet. (I regularly get -0.5dBV to -0.6dBV tested to half rated load).
But it does prove that the amplifier is capable of delivering current without the output voltage collapsing. If it can't deliver current then it is current crippled. Most chip amps fall into "current crippled" category.
I also look at the current delivery into 1/3rd rated load, but limited to a very short test period (two to ten seconds is sufficient). - it raises heatsink temperature a lot if sustained. I expect the amplifier to not enter any protection mode while delivering current into 1/3rd rated load.
I also build 8ohms capable amplifiers. I don't have any 4ohms speakers, except in my car.
My 8ohms capable amplifiers must be able to drive a 4r0 dummy/test load to near the maximum output voltage that is available into my rated 8ohms load.
I use the same criteria as posted in another Thread today.
16r/8r/4r and expect the power to be 60W/100W/180W
I do not expect an 8ohms rated amplifier to drive a 2ohms load.
I do expect a 4ohms rated amplifier to drive a 2ohms load.
That 3times power (180W/60W) going from 16r (double the rated load) to 4r(half the rated load) was my "old" standard for acceptable current delivery.
Having read R.Cordell, who recommends 180% of maximum rated power into half rated load impedance, I now adopt his standard for current delivery. It is slightly more onerous than the 3times rule.
Look at that 60/100/180. It too shows that 180% into half rated load.
To get to that 180%, the output current must be delivered with the output voltage dropping no more than 0.46dBV That is not an easy target to meet. (I regularly get -0.5dBV to -0.6dBV tested to half rated load).
But it does prove that the amplifier is capable of delivering current without the output voltage collapsing. If it can't deliver current then it is current crippled. Most chip amps fall into "current crippled" category.
I also look at the current delivery into 1/3rd rated load, but limited to a very short test period (two to ten seconds is sufficient). - it raises heatsink temperature a lot if sustained. I expect the amplifier to not enter any protection mode while delivering current into 1/3rd rated load.
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Hi there, I'm interested in 100W boards. How much is it to ship it to Florida?
Thank you,
Vlad.
Use 10 mm round stick and wind 13 winds of 1 mm or 1.2 mm wire.
If the power amp is going to be powered with no PS regulator than use 2x36 AC secondary winding, if PS regulator used, use 2x40 V AC.