• Disclaimer: This Vendor's Forum is a paid-for commercial area. Unlike the rest of diyAudio, the Vendor has complete control of what may or may not be posted in this forum. If you wish to discuss technical matters outside the bounds of what is permitted by the Vendor, please use the non-commercial areas of diyAudio to do so.

Switched Mode Power Supplies (SMPS)

Status
Not open for further replies.
Jump to Latest
#364
thomaspf said:
I finished a Faraday cage for one of my SMPS800R and experimented with an additional ferrite core.
Click to expand...

Speaking of ferrite cores, might it be worthwhile to put the kind used on RCA interconnect cables on each set of +/- wires feeding an amp module?

Cristi, might you consider adding Farday cages or offering them as an option?

From what I've read there are few situations where they wouldn't be recommended.

Also, I think that most of us intend to use these inside a case with front or back panel power switch, so maybe it should be standard to have no power switch or IEC connector (this is for mains power, right?).

Thanks
 
Last edited:
#365
SoldierAnt: the aux. output can provide up to 500mA each rail, do not exceed this current otherwise the fuses which protect the aux section will burn. 500mA is more than enough for any preamplifier stage or aux. circuitry. the negative aux. output can be left floating if is not used. does not require any load and is useless to waste power by adding any resistor.

Noah: the type of ferrite cores which you mention are widely used as common mode choke on many interconnect cables. they can reduce the EMI by few dB if they are properly sized and installed.
To use a faraday cage, a shielded case for the power supply, the board must be redesigned, according to the case size and shape. one of the next power supplies at which i'm working at right now, will include such case. the radiated EMI decreases exponentially with the distance from the source, so, by placing an unshielded power supply further away few inches could lead to same result as by using a completely shielded one, next to the amplifier. also, the signal cables routing and GND connection can have a major effect.
I repeat, the SMPS800R, which is the only power supply which has the IEC connector on board, was designed to be used with the TA3020v3d amplifier, as a very compact unit, where all the space should be used at maximum.
 
#366
Cristi said:
one of the next power supplies at which i'm working at right now, will include such case.
Click to expand...

What will be its power output and when will it be available?

Cristi said:
I repeat, the SMPS800R, which is the only power supply which has the IEC connector on board, was designed to be used with the TA3020v3d amplifier, as a very compact unit, where all the space should be used at maximum.
Click to expand...

sorry, I missed it the first time
 
#367
Shielded Power supply

Cristi said:
To use a faraday cage, a shielded case for the power supply, the board must be redesigned, according to the case size and shape. one of the next power supplies at which i'm working at right now, will include such case. the radiated EMI decreases exponentially with the distance from the source, so, by placing an unshielded power supply further away few inches could lead to same result as by using a completely shielded one, next to the amplifier. also, the signal cables routing and GND connection can have a major effect.
Click to expand...

This is very exciting. Any more data on size and output. I migth wait for this instead on pushing further down the path of building the cages for the SMPS800R.

Cheers

Thomas
 
#368
noah katz said:
Cristi, might you consider adding Farday cages or offering them as an option?

From what I've read there are few situations where they wouldn't be recommended.
Click to expand...

For what it's worth, I've never experienced any interference problems with the 300 and 500 watt Connex supplies I've used. And that's with the SMPS sitting only a centimeter away from the amplifier unit.

A built-in Faraday cage would add bulk, and make the SMPS harder to install. If you think a cage would help in your situation, it might be easier to get some mesh and roll your own. 😉
 
#369
SoldierAnt76 said:
A built-in Faraday cage would add bulk, and make the SMPS harder to install. If you think a cage would help in your situation, it might be easier to get some mesh and roll your own. 😉
Click to expand...

i agree with you, that's why i haven't used them with the current power supplies yet. the source of noise is very often not easy to found and is easier to believe that the noise could come from the power supply, instead of inspecting further the circuit wiring and layout. a signal cable routed close to the power supply transformer, or a shielded signal cable with GND connected at both ends, a GND loop, or any other incorrect routing can be the cause of the noise.
 
#370
I am simply looking at the supply rails of the amplifier board and see exactly the same ~100 Khz ripple I see at the output of the SMPS800R. There is noting else that generates a ~100 Khz ripple like this.

Adding the cage does reduce that ripple quite a bit.

Have you decided on the output power and dimensions of the caged suppply you are building?

Cheers

Thomas
 
#371
Cristi,

Depending on the size of the heat sink you offer with the A1000SMPS, it might not fit in my case.

What are its dimensions?

Also what are the dimensions of the heat slab, and does it protrude beyond the 120 mm dimension?

If I need to make a custom one, what should its fin area be?

Also please the dimensions of your speaker protector.

Thanks
 
Last edited:
#373
Hi Christi,

I sent an email with this question through your website, but I thought this might be a useful question for anyone else doing what I'm doing.

I bought an SDS-470 kit from Class D Audio. Note: there's very little info about this board on the website, but, with 4 ohm speakers, it does 600 WPC stereo, and 800 Watts bridged.

The kit came with a linear power supply, which works great. But I'm interested in trying a SMPS to hopefully lower the power consumption (i.e. make the overall amp more efficient). Also, I'd like to save on size and weight. I'm using this amp in stereo mode now; but if the SMPS gets the power consumption down enough (and sounds as good or better than the linear PS), then I intend to get another SDS-470 and run them both bridged (i.e. monoblocks).

Tom (of Class D Audio) said the PS voltage needs to be +/- 65 to 68 Volts.

He suggested the SMPS800R. I was wondering what your (or anyone else's) thoughts are on this unit versus the A1000SMPS. Why might I choose one over the other?

Soon as I figure out which one I should get, and confirm that the output voltage can be made as described above, I'm all set to order! 🙂

Thanks!
 
Status
Not open for further replies.
Top Bottom