Yes... it is fine with or without input, or even while connecting and disconnecting.
I was worried the above discussion would be misinterpreted as a discussion on instability, but what we're talking about is not amplifier instability.
It's more of a discussion on the behaviour of the amplifier in a pretty distant corner case of extreme high frequency clipping. It's easy to replicate on a test bench with a dummy load and a generator, but in the real world, if you're clipping your amplifier that badly, then you're not running a powerful enough amp.
Even as such, there is no oscillation or sign of instability in the amp, it simply hangs onto the rail a little bit while it regains composure after a heavy clipping episode. At no point does it lose stability though. Still not desirable behaviour to be sure, but in these conditions your bigger problem is the severe clipping and not the tiny discontinuity caused by the rail sticking.
Cheers,
Owen
yeah sorry mate, when using the word instability, I thought carefully about it before leaving it there, but it was the best word for the job. I went on to specifically assign it to the conditions in the power supply and its trace at that point, but did worry someone might make that mistake that I was talking about stability in general.
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Will 22pF, or 18pF do the job.
20pF is an E24 range value and probably quite difficult to source.
20pF is an E24 range value and probably quite difficult to source.
Hi Andrew,
Yes, both 18 or 22 will be fine. Just make sure it's a tight tolerance mica or Teflon.
If you're targeting 100W then go for the 22pF but if you're getting closer to 200W then the 18pF would be the better bet.
Also, your package shipped out this morning with your kits and the extra fets, so you should see it in a couple of weeks.
Cheers,
Owen
Yes, both 18 or 22 will be fine. Just make sure it's a tight tolerance mica or Teflon.
If you're targeting 100W then go for the 22pF but if you're getting closer to 200W then the 18pF would be the better bet.
Also, your package shipped out this morning with your kits and the extra fets, so you should see it in a couple of weeks.
Cheers,
Owen
Just received my boards, thanks Owen! Wow... they are.. TINY! and this thing can output 400w? 😀
I would probably stop at 300W with a single pair of fets. If you run multiple parallel pairs, you could go much higher.
Cheers,
Owen
Cheers,
Owen
Hi,
I will play safe and aim for 100-120W 8Ohm. 300W and I'd be worried not getting the heat out of two TO-264.
I will play safe and aim for 100-120W 8Ohm. 300W and I'd be worried not getting the heat out of two TO-264.
Ah! not to worry guys, I only need 100w/channel.. I just looked at the class AB worksheet on the first page, goes up to 400w under 2ohms.. but talking about this maybe I can ask some extra advice? Roberto already gave me his opinion on it. I have 2 woofers per speaker, 4ohm min each. If I run them on parralel, I can save 2 boards/SMPS for extra channels in a HC setup. I will run 45/55v.
edit: I just ran a simulation on the woofer, dipole mode. Can't reach xmas with these amplifier settings, which is fine. I still reach 100db, with 50VA power at 20hz, and 210VA at 100hz with one driver. Should be fine for parralel?
edit: I just ran a simulation on the woofer, dipole mode. Can't reach xmas with these amplifier settings, which is fine. I still reach 100db, with 50VA power at 20hz, and 210VA at 100hz with one driver. Should be fine for parralel?
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big difference between having the power supply/overhead there and actually shooting to use it in a continuous manner. if going for that much I would probably play it safe and add another pair of fets
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try and monitor temp, you'll need some pretty serious mounting arrangements and good TIM. the fets can handle it, but its a matter of getting the heat out of them
bass amps see a lot more extended transients too, I presume we are talking bass here. its been covered in here as well, but the amp is ok with 4ohms, even 2ohms, but at those powers probably happier with 6-8ohms
Like lolo, I'll probably use less than 10W all the time. Heck, I think if I'll ever use more than 10W, I think my neighbours won't like me anymore. 😀
And I won't use it as sub amplifier, I'll power XTZ 93.23 with The Wire. I already have DIY active sub with Focal Audiom woofer.
As you mentioned TIM...what are you going to use?
And I won't use it as sub amplifier, I'll power XTZ 93.23 with The Wire. I already have DIY active sub with Focal Audiom woofer.
As you mentioned TIM...what are you going to use?
well I dont think either of you have anything to worry about, sure transients can be many times the continuous, but it would be some whacked out music that is 10W continuous but with 350W transients extended enough to take you out of the SOA if youve mounted well.
Keratherm Red 😀
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