In the old computers of yesteryear, the idea was to protect the computer's bits at the expense of the power supply. Likewise one would think to protect the speaker at the expense of the amplifier - which has presumably faulted anyway.
The "knows what to and what not to do under all possible listening conditions" problem is certainly an interesting one. It's a bit like a compressor / expander - the audio envelope circuit cant know what's coming in time, so it's going to be a bit late to respond. Here not only that, but you have to figure out what's honestly a valid output. No wonder some designs are so elaborate.
The "knows what to and what not to do under all possible listening conditions" problem is certainly an interesting one. It's a bit like a compressor / expander - the audio envelope circuit cant know what's coming in time, so it's going to be a bit late to respond. Here not only that, but you have to figure out what's honestly a valid output. No wonder some designs are so elaborate.
Your sure right about that. At 33,000uF that little 5" would probably blow.
I was meaning to suggest something more like 6 to 8,000 uF.
When I said "no phase shift", I meant 'realistically' little in the audio-band.
One of the amazing things about today's high quality AtoD > DtoA technology is that you can insert a 'micro delay'
into the main signal path, thereby creating 'pre-emptive intelligence' into things like compressors & limiters. (no over-shooting)
But you only get clean clipping on a capacitively coupled amp (at low frequency) if the pole frequency formed by the cap and speaker is lower than all of the rest of them. Power supply filter, bootstrap (if applicable), feedback cap, input coupling cap. If you use smaller values, you need to push the rest of the low frequency poles up too. You may wind up more low frequency phase shift (or roll off) than you want.
Its the same reasoning which drives 10 to 20,000 uF being the right number for the power supply cap (Even on DC coupled amps). You want the poles staggered, and roll off dominated by the input coupling cap. This also serves to minimize power-up transients. Things charge in the proper order.
Yes, that sort-of follows the logic of removing TIM by progressively increasing the bandwidth of
each 'section' in an amplifier.
However, I don't believe in/endorse ever listening to clipping & distortion >
that's why I use a very high power amp. with 'anti-clip' and tons of headroom.
I think you may be unnecessarily complicating the use of AC coupling.
each 'section' in an amplifier.
However, I don't believe in/endorse ever listening to clipping & distortion >
that's why I use a very high power amp. with 'anti-clip' and tons of headroom.
I think you may be unnecessarily complicating the use of AC coupling.
The circuit https://www.diyaudio.com/community/threads/protection.391839/post-7428567 demonstrates exceptional performance and serves as an ideal complement to a fast-blow 6.3A fuse in this specific application, whichever is triggered first. Its effectiveness in safeguarding your output devices is highly probable. Unlike a fuse, which might not offer comprehensive protection in all scenarios due to its limited overdrive-only rating, this circuit is meticulously engineered to comprehensively address potential issues. False activations are a rarity within this setup. Any activation that does occur would likely play a pivotal role in upholding the integrity of your output devices. This dual-layer protection strategy is anticipated to operate exceedingly well. It's important to note that this analysis assumes the presence of two output transistors per side, within the +/-50VDC ±10% rails.
"Likely play...".
"anticipated to operate exceedingly well."
Am I to infer that all you have done is simulated this design, and that you have not actually built and tested this protection circuit for real?
If that is the case, then how on earth can you honestly expect anyone to trust the protection of their speakers and system to some undocumented over-complicated unproven circuit off the internet?
Ant.
Someone could built it and test it - and then decide if he wants to use it. I’ve built and tested protection systems as complicated as this. Just the “DC detect, and open the relay” parts are quite simple and reliable.
This is an amp with a comprehensive protection system. It was used to test the protection system, prior to implementing it in a much larger amp (still in development). Only a small portion of it is “amplifier”. Doesn’t need all of it working, to protect speakers from DC. In addition, it has power supply sequencing and fault detect, fan control, and 4 stages of temperature protection (Different features kick in as it gets hotter, ultimately shutting down entirely at 90C).
This is an amp with a comprehensive protection system. It was used to test the protection system, prior to implementing it in a much larger amp (still in development). Only a small portion of it is “amplifier”. Doesn’t need all of it working, to protect speakers from DC. In addition, it has power supply sequencing and fault detect, fan control, and 4 stages of temperature protection (Different features kick in as it gets hotter, ultimately shutting down entirely at 90C).
Attachments
Thanks for your interest. Some of my ideas are revolutionary and sometimes abstract for purposes of reasoning and generalization , some are more aimed at industry experts so that when you buy an audio product from your favorite brand, it may have those modification built in for a better experience for you. Not all ideas are good, time also does play a role in evaluating whether it is a good idea. Check out this video
More performance charts of the intermediate protection.
https://www.digikey.com/en/products/detail/epcos-tdk-electronics/B59052D1070A040/11201191
https://www.digikey.com/en/products/detail/epcos-tdk-electronics/B59052D1070A040/11201191