My softstart to control AC input, 300VA toroid will trip my mcb. However I don't understand your softstart terminology on mute pin (on LM3886 ?)
gadut - don't want to start an argument - really - really - honest. 
, but I purposely avoid the soft start with the MyRefs as, to my understanding, the power-up glitches are handled sufficiently by the on board protection system in the MR design. I have one for a 27,000 uF X 8 cap bank with dual 500VA transformers on a discrete build, but haven't had any problems even when it's not in the circuit. What's your reasoning - just curious.
, but I purposely avoid the soft start with the MyRefs as, to my understanding, the power-up glitches are handled sufficiently by the on board protection system in the MR design. I have one for a 27,000 uF X 8 cap bank with dual 500VA transformers on a discrete build, but haven't had any problems even when it's not in the circuit. What's your reasoning - just curious.
gadut - don't want to start an argument - really - really - honest.
I'm not trying to make any argument actually, it's just a new thing to me
basically I want to avoid additional circuit, but the only reason that I use that softstart kit is to avoid mcb trip (tripping) - hopefully you get what I mean. previously every time I turn it on, pitzzzzz and my mcb trip, and it's so annoying.My house is 1300VA, but mcb trip with MP 300VA. I never tried to turn on my aragon2004, because i've tested on my friend's house @2200VA and his mcb also trip because of my aragon, eventhough not all time. I don't want to compare my mains with your mains, the company that produce the electricity are in different league
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The inrush current to the transformer and the mains supply caps can trip breakers regardless of the amp / circuit using the supply.
A CL60 inline with the transformer is a simple cheap alternative.
A better (but more expensive) alternative is SMPS... The new ones are VERY good and will equal a traditional linear power supply.
A CL60 inline with the transformer is a simple cheap alternative.
A better (but more expensive) alternative is SMPS... The new ones are VERY good and will equal a traditional linear power supply.
There are several advantages to the zener soft start. First, its a soft start so thats nice. I had a lot of turn on pops when I lived in Rhode Island and my circuit was a little different. Now even with a 400va toroid and 60000uf of capacitance I dont have an issue where I would need soft start. Nevertheless it would have been nice in Rhode Island.
Second, its only one more part so thats cheap and easy.
Third, as quoted from Nat Semi "If the mute pin is sourcing less than 0.5 mA, the nonlinear attenuation curve may induce crossover distortion or signal clipping." Maybe we should be looking at using much lower value resistors in the mute pin circuit!
So in section 4, page 15 of this document
AN-898 you will find a discussion on the mute pin. It also pertains to the performance of SPIKE. Getting the mute pin operating properly, not just operating, looks like it could be a performance enhancer
Apex uses this in his amps. Let me find a link... HERE
He uses a 10k resistor plus zener still but I'm just thinking that maybe the current sourced by the Mute pin could be messed with for better sound. I know Danielwritesbac has experimented with this and used a trimmer as a variable resistor instead of a regular resistor in this position and I think Nanook did too but I cant recall for sure.
So if you look at Apex' circuit you can see that the amp is not allowed to begin producing ANY sound at all until the rails are up to 16V in which case its not going to pop. And Bob is right for that for the most part the soft start is negligible on this amp because of built in protections but it seems that a zener/resistor combo could be an improvement.
I guess if you are tripping breakers a CL60 is, to me anyway, a better solution than spending 30 bucks on an ebay soft start. Didnt know til I wrote all this stuff that you needed soft start because you were tripping breakers. I guess I dont even think about that CL60 in my amp, its such a no brainer that it always goes in. So I hadnt considered your inrush current.
I suppose I could also shuddup and leave the posts as photos!
Second, its only one more part so thats cheap and easy.
Third, as quoted from Nat Semi "If the mute pin is sourcing less than 0.5 mA, the nonlinear attenuation curve may induce crossover distortion or signal clipping." Maybe we should be looking at using much lower value resistors in the mute pin circuit!
So in section 4, page 15 of this document
AN-898 you will find a discussion on the mute pin. It also pertains to the performance of SPIKE. Getting the mute pin operating properly, not just operating, looks like it could be a performance enhancer
Apex uses this in his amps. Let me find a link... HERE
He uses a 10k resistor plus zener still but I'm just thinking that maybe the current sourced by the Mute pin could be messed with for better sound. I know Danielwritesbac has experimented with this and used a trimmer as a variable resistor instead of a regular resistor in this position and I think Nanook did too but I cant recall for sure.
So if you look at Apex' circuit you can see that the amp is not allowed to begin producing ANY sound at all until the rails are up to 16V in which case its not going to pop. And Bob is right for that for the most part the soft start is negligible on this amp because of built in protections but it seems that a zener/resistor combo could be an improvement.
I guess if you are tripping breakers a CL60 is, to me anyway, a better solution than spending 30 bucks on an ebay soft start. Didnt know til I wrote all this stuff that you needed soft start because you were tripping breakers. I guess I dont even think about that CL60 in my amp, its such a no brainer that it always goes in. So I hadnt considered your inrush current.
I suppose I could also shuddup and leave the posts as photos!
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I was wondering why people were suggesting using the mute function as a soft start
They had me scratching my head there for a bit
I bought Musical Fidelity's V-PSU to power my V-DAC, V-LPS and my diy dual chip C-Moy headphone amp. Turns out it is based around an SMPS
Musical Fidelity even fitted a larger version inside their new M1 PWR power amp.
When designed specifically for audio and well filtered, it seems they can be very good.
I thought I could hear footsteps approaching - you and Andrew must wear the same shoe brand. I'll just comment that as few components as possible - whether they be signal or power - between the music source and the speaker is simply my personal preference. If the system doesn't need it, I don't want it.
But as Mr. T often reminds us, personal and equipment safety is at the core of everything. The distinction between those two functions is certainly correct and of course should be taken into consideration.
I'll just comment that as few components as possible - whether they be signal or power - between the music source and the speaker is simply my personal preference. If the system doesn't need it, I don't want it.But as Mr. T often reminds us, personal and equipment safety is at the core of everything. The distinction between those two functions is certainly correct and of course should be taken into consideration.
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Youre right Andrew and I wasnt thinking of those that wouldnt differentiate between soft start and a turn on delay which I was using interchangeably as I was really getting at the benefit of both in that they both will get rid of that turn on THUMP.
I did differentiate at the end of my post when I realized the guy I was responding to was talking about needing it for inrush current which just hasnt been an issue for me so that problem that a soft start solves wasnt at the forefront of my thoughts or response.
I did differentiate at the end of my post when I realized the guy I was responding to was talking about needing it for inrush current which just hasnt been an issue for me so that problem that a soft start solves wasnt at the forefront of my thoughts or response.
Post some then!
As Andrew T would no doubt say, safety first - second and last.
No idea what kind of footwear he favours Bob, but if I had to guess, I'd say safety boots
I got really excited when I saw the update email in my inbox. So here's a dang picture of my soon-to-be-finished chipamp, an audiosector.com kit with single transformer, PCBs almost complete, just waiting for the time to finish drilling the holes for heatsink mounting on the other aluminum plates so the enclosure can be completed.
I hadn't cut aluminum stock before this. Quite a bit of fun, and I almost have my drilled holes with a 0.5mm tolerance (the bottom of the enclosure is visible..). I'll post photos when I'm done.
More photos, please. And yes, my climbing shoes and old Brooks saddle are all on my "workbench".