I have built an M2 using a pair of Meanwell LRS units per side and it works great. There is an active thread on the upcoming F5m also using these supplies. A bigger amp like Stasis, Honey Badger or similar 100W+ amp might require a +/-48V supply and with a 4 ohm load we're up to a peak current of 12A per rail. This is available via SMPS and I can both afford it and lift it!
I have two questions:
1. Is it OK to just turn on a high current SMPS from cold and dump 10s of amps of inrush current into the downstream components? Is it deleterious to the health of the SMPS and/or downstream components (am I worrying over nothing?).
2. If it is not OK, then it appears there a need for a something to go between the SMPS unit and the amp boards, perhaps enabling the addition of some local capacitor reservoir for those who feel it beneficial. It would be great if there could be a sanctified version of a soft start board for these applications.
One of the potential advantages of the SMPS is that it can be cheap and although expensive solutions exist with soft start, speaker protection etc., this choice negates the cost benefit. And as Nelson Pass has astutely noted; we're cheap.
😉
Maybe if you take the store soft start circuit and put the SMPS output across AC1 and AC2 and the load across XFR1 &2, leave D2 & D3 open, short D1 & D4 and choose appropriate high current /. voltage versions of the relay and capacitor maybe it does the right thing, but I really don't don't know.
As a cut & paste artist / solder slinger I am aware that I don't know what I don't know, but it appears that this simple (?) module capable of options for different voltages and current and bipolar supplies would be of wide utility given the increasing number of SMPS based audio toys.
I have two questions:
1. Is it OK to just turn on a high current SMPS from cold and dump 10s of amps of inrush current into the downstream components? Is it deleterious to the health of the SMPS and/or downstream components (am I worrying over nothing?).
2. If it is not OK, then it appears there a need for a something to go between the SMPS unit and the amp boards, perhaps enabling the addition of some local capacitor reservoir for those who feel it beneficial. It would be great if there could be a sanctified version of a soft start board for these applications.
One of the potential advantages of the SMPS is that it can be cheap and although expensive solutions exist with soft start, speaker protection etc., this choice negates the cost benefit. And as Nelson Pass has astutely noted; we're cheap.
😉
Maybe if you take the store soft start circuit and put the SMPS output across AC1 and AC2 and the load across XFR1 &2, leave D2 & D3 open, short D1 & D4 and choose appropriate high current /. voltage versions of the relay and capacitor maybe it does the right thing, but I really don't don't know.
As a cut & paste artist / solder slinger I am aware that I don't know what I don't know, but it appears that this simple (?) module capable of options for different voltages and current and bipolar supplies would be of wide utility given the increasing number of SMPS based audio toys.
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Hello BeardyWan! Were you able to find or resolve anything about it?, I am researching this, trying to find a soft start for an SMPS source, at the input it only has an NTC Thermistor mf72 1.5d25" 1.5 OHM 20% 10A 27.5MM as protection or soft start, but this is still not enough for the circuit , since it is delicate and fails at some startup; then it will be necessary to add some limiter to the circuit at the secondary input or output towards the source output capacitors, but I am in doubt about what to do, the circuit that I need to protect is quite large. basic and unstable at startup
I resolved that I do not know enough to pioneer a solution to this question. Instead I have swallowed the pill and am building something using a more traditional PSU.
cheers
cheers
I wonder if the store’s vfet relay might be a solution. It was meant to get rid of thump on start up and such. https://diyaudiostore.com/products/nelsons-psu-filter
The Meanwell series has a soft start built in. If your inrush is greater than the PSU's capability (about 117% of rated load with a 115VAC input, slightly higher if running on 230VAC), then the Meanwell will go into "hiccup" mode for a short period. All should be fine afterward, and no downstream components will be over-stressed. Pops and clicks might be heard though during the "hiccup" period.
See: https://www.meanwell.com/productPdf.aspx?i=411&pdf=TFJTLTEwMC00OC1ycHQucGRm&a=2
See: https://www.meanwell.com/productPdf.aspx?i=411&pdf=TFJTLTEwMC00OC1ycHQucGRm&a=2
