Anyone played with one of these? Seems like a very cheap way to get a basic SE amp powered - even includes delayed B+
HIFI 250W Switch Power Supply DC300V@0.6A +12.6V@4A +6.3V4A For Tube Amplifier PSU|Operational Amplifier Chips| - AliExpress
HIFI 250W Switch Power Supply DC300V@0.6A +12.6V@4A +6.3V4A For Tube Amplifier PSU|Operational Amplifier Chips| - AliExpress
People often stay away from switchmode powersupplies because they can spit out a lot of HF noise. With Chinesium stuff it is even more of a gamble. Can be nice for experimentation though, especially at that price
FWIW I found a review of this module:
“Perfect packaging and fast shipment. Product : Voltage and current are perfect BUT... it's Noisy...Very noisy. I can hear many switch noises from this power supply in the loudspeakers. Finally I prefer classic power supply with transformers. 05 Mar 2021 03:51”
From: 250W Buis Eindversterker Buis Versterker Schakelende Voeding 300V0.6A 12.6V4A 6.3V4A Vertraging Open Circuit|Versterker| - AliExpress
Regards, Gerrit
“Perfect packaging and fast shipment. Product : Voltage and current are perfect BUT... it's Noisy...Very noisy. I can hear many switch noises from this power supply in the loudspeakers. Finally I prefer classic power supply with transformers. 05 Mar 2021 03:51”
From: 250W Buis Eindversterker Buis Versterker Schakelende Voeding 300V0.6A 12.6V4A 6.3V4A Vertraging Open Circuit|Versterker| - AliExpress
Regards, Gerrit
I wouldnt buy mains powered switchers from china, However that module looks well made. The designer knows his stuff. Lytics are likely to a price, but all in all not a bad product IMHO.
You can reduce the output noise with a 100uH 10uF external filter and a ferrite ring around the output wires.
You can reduce the output noise with a 100uH 10uF external filter and a ferrite ring around the output wires.
Unless I can see the schematic I’d be sceptic.
I’d like my smps to have active pfc, be isolated and also be performant (efficiency, ripple and noise).
You can always add filters but switching speed and other aspects are more ingrained in the design.
I’d like my smps to have active pfc, be isolated and also be performant (efficiency, ripple and noise).
You can always add filters but switching speed and other aspects are more ingrained in the design.
Perhaps do some google searching for forum threads - that psu has come up before.
It has no safety compliance for mains AC connection, so even though it looks as well built as any other mains AC supplied psu you take all the risk.
Just for diy use, I'd buy it for initial assessment, but it is a few $, and it preferably needs some bench testing to see how it manages cold heaters and B+ load changes. It also helps if you know smps and can assess how well the pcb is laid out and the parts it uses and the cooling requirement for your specific application - otherwise you throw the dice when you use it in any practical amp and have to then work through any issue that may arise (from thermal shutdown to smps control mode changes to ground loop noise).
It has no safety compliance for mains AC connection, so even though it looks as well built as any other mains AC supplied psu you take all the risk.
Just for diy use, I'd buy it for initial assessment, but it is a few $, and it preferably needs some bench testing to see how it manages cold heaters and B+ load changes. It also helps if you know smps and can assess how well the pcb is laid out and the parts it uses and the cooling requirement for your specific application - otherwise you throw the dice when you use it in any practical amp and have to then work through any issue that may arise (from thermal shutdown to smps control mode changes to ground loop noise).
I've ordered this one up to test. 250W will be derated to about 100W since I plan to cook it in a ventless chassis. It should work well for my Little Miracle design (10Wx2)
250W tube power amplifier tube amplifier switching power supply 300V0.6A 12.6V4A 6.3V4A delay open circuit|Amplifier| - AliExpress
250W tube power amplifier tube amplifier switching power supply 300V0.6A 12.6V4A 6.3V4A delay open circuit|Amplifier| - AliExpress
They can generate audio tones if you don't load them enough. Say 30% or more of full current. Looks OK.
It looks well built, nice walled off barrier strips, etc. I like the form factor of an aluminum tray sub-chassis, with all transistors facing outward then simply sinked to the tray. I can love that form factor for making any linear PCB based PS "module", filament module, Maida module, etc. I think I'll steal that form factor!
I just tried this PSU in my mini 6V6 SE amp (2 x 6V6 + 6SN7) . Had some problem with HV delayed start so reduced delay to 3-5 seconds by changing resistor on NE555. Now it works OK. No audible noises. No overheating (no fan required).
not anymore, i have built several of NP's ACA and noise did not seem to ba an issue, i would like to try smps on tubes also...
Here's a 600 Watt 0 to 250V up to 2.5 Amp bench supply with adjustable current limiting and meters for $2 !!! Looks like it works. Another one listed at $50
HOEFER SCIENTIFIC INSTRUMENTS PS 250/2.5 AMP TRANSPHOR/ELECTROPHORESIS DC POWER | eBay
Hoefer Scientific PS 250 2.5 Amp Transphor / Electrophoresis DC Power Supply | eBay
HOEFER SCIENTIFIC INSTRUMENTS PS 250/2.5 AMP TRANSPHOR/ELECTROPHORESIS DC POWER | eBay
Hoefer Scientific PS 250 2.5 Amp Transphor / Electrophoresis DC Power Supply | eBay
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I have decided the SMPS are so cheap they are worth testing and have ordered the same power supply for testing. I intend using the SMPS in a SE amplifier and will report back to this thread re noise and performance when it is going.
The SMPS should make the amplifiers lighter and maybe look cleaner with one less transformer.
Ken Kranz
It may be related to PSU protection circuit or even faulty protection circuit of my PSU only. The HV after 30 sec delay goes to 300VDC and immediately turns off in infinite loop. After delay disabled all works OK.
That probably means the PSU can't supply the inrush to a circuit with hot tubes. Personally, I'd rather have a fire than protection in an SMPS.
It is possible. I also tried to use another (smaller) switching PSU with same delay function (Tube Amplifier Switch Power Supply Board For Preamp Tube Radio AC95V-260V input | eBay) and it worked perfectly with no mods and no inrush issue with hot tubes. The only small issue with this one is that you have to connect both grounds (HV and Filament) together in order to avoid hum.