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Well I did It! I managed to damage my phono pre-am (sigh)

So, I managed to damage my SimAudio Moon 110lp v2!

I am embarrassed to even be posting all this but whatever, perhaps someone could learn from my mistakes.

Recently I had made a post asking for feedback on Tube Phono Stages as I have been pondering about upgrading.

But I also wanted to see if I could perhaps squeeze out more performance out of the SimAudio and hence I also inquire about SUT's and what they can do.

One other aspect that I thought may improve the performance was getting a LPS.

So, I purchased the Ifi LPS as I had read good reviews of it (that unit is fine by that way). 

My SimAudio is 24vdc and I bought the Ifi 24v 2.5amp, thinking that would be the correct LPS.

It was delivered and I unplugged everything from the SimAudio.

The Ifi comes with different plug adapters but the default plug, plugged right in and I thought great, I won't have to use the adapters.

Plugged everything in and the SimAudio blue light came on but no sound!

Pugged the SimAudio back to its power adapter and all sounded fine.

Then I though, well maybe I do need to use one of the adapters and tried the correct one and same result, no sound. 

Went back to the default plug and then the blue light was flashing on the Sim and just a few seconds later, a puff of white smoke!

Unplugged everything immediately but knew right away the Sim was done for.

No other damage, the Ifi is fine and I will be returning that.

But my little SimAudio is no more.

Damn! I really liked that unit and was going to keep that around for a 2ndary system.

I feel horrible. At least it's not a terribly expensive unit but I just feel like crap about the situation.

Now for sure, I am going to have to get a new Phono Stage.

I just don't understand what went wrong, power wise, I thought for sure I was getting the correct unit.

Well, I'm just ranting here and getting it out as only you guys will understand.

Thanks for listening.

Jay 

 

jay73
jay73's avatar
jay73 OP
246 posts
 

@dover Hi, I know you can't say for sure because you don't have the equipment in front of you but are you saying that I probably should have used the white adapter, which the ifi did come with?

dover
2,496 posts
 

@jay73 

Hi - short answer is I don't know.

Couple of things -

I checked on fleabay and found LPS for the Moon 110 - its 24v 1amp max.

It is possible your ifi at 2.5amps may have supplied momentarily too much current on switch on. One thing to be aware of is never switch gear on and off and on again straightaway because on switch on you get an inrush, and power supply caps that have not fully discharged can be overcharged if the power is turned off and on too quickly in succession.

With regard to polarity - you could get a tech to check your original moon SMPS for voltage, current and polarity - would only take a few minutes. If you don't know a tech, try companies that provide PA equipment - they usually have techs to service their gear. Alternately your local hifi shop may have a list of techs you could use.

I would try a local tech first as it is probably the cheapest option. 

 

 

 

 

devinplombier
1,637 posts
 

@dover

It is the device, in this case the phono stage, that determines how much current flows into it. If the device is asking 500 mA from a PSU that's rated for 50 A, only 500 mA will flow. In other words, there is no way a PSU can damage a device by supplying it with too much current, unless it's asking for it. For instance, if the device that normally uses 500 mA develops an dead short, then the PSU will pump 50 A into it and fry it to a crisp; but that's the device's fault, not the PSU's.

 

troidelover1499
258 posts
 

Don't feel bad as I think everyone who has been at this for a while has had their fair share of stupid and unlucky moments.  We just have to live and learn and not make the same mistakes twice haha.

dover
2,496 posts
 

 

@devinplombier 

If the device is asking 500 mA from a PSU that's rated for 50 A, only 500 mA will flow. In other words, there is no way a PSU can damage a device by supplying it with too much current,

In theory that is true, but there are several exceptions. Remember he is switching from an SMPS to LPS. The internal regulators may have specific requirements.

My suspicion would be inrush current. Linear supplies often have large filter capacitors, which can cause a high inrush current upon startup. This can trip protection circuits or damage components in a device designed for a lower-demand SMPS.

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