Troubleshoot Magni 3

arunlouie

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Hello All,

Hope all are safe!

I am looking for help on how to troubleshoot a problem in Magni preamp. I got this from US and never checked. Dropped the adapter there as it was 110v. Now with new adapter to matched 14v I see the power light is on but no sound. All components inside is intact (no burning anything).

Please guide me on how to troubleshoot.

PS: I have limited knowledge on how to use multimeter.
 

stefan

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Maybe the smps doesn't provide enough amps? I replaced a 1.5 amp Casio keyboard PSU with a local made 2 amp unit and the keyboard kept cutting out, got an original one yesterday and works perfectly. I suggest you get a mean well PSU either 12 or 15 volt highly reliable and have minimum of 3 years warranty, you can adjust the voltage accordingly.
 

arunlouie

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Voltage mentioned in the adapter was 14v 1.5amps,. After so much search got 14v adapter and it doesn't works. Multimeter shows close 14v (13.8v). I have a decent multimeter, so I believe the reading is correct.

If power is the issue, is there a way to check? Or Can someone help to lend magni adapter in Chennai just for a day. If it works I shall buy original one.
 

vizeta

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As per the pictures of the Back panel of the product, it requires 14V AC (not DC). The manufacturer website also suggests to use 14/15V 1500 ma AC power adapter and the AC to DC conversion circuit is inside the unit.

Ideally, if the AC injected to the unit is simply converted to DC, 14volt DC should also work. I am not sure if the circuitry inside needed AC power before converting it to different voltages (for example another transformer). In that case, I would advise you to not inject DC power to the unit, as it might damage the parts inside.

The safest way to check it with a 12-14volt transformer (>1500 ma rating) and test the unit with it.
 

arunlouie

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As per the pictures of the Back panel of the product, it requires 14V AC (not DC). The manufacturer website also suggests to use 14/15V 1500 ma AC power adapter and the AC to DC conversion circuit is inside the unit.

Ideally, if the AC injected to the unit is simply converted to DC, 14volt DC should also work. I am not sure if the circuitry inside needed AC power before converting it to different voltages (for example another transformer). In that case, I would advise you to not inject DC power to the unit, as it might damage the parts inside.

The safest way to check it with a 12-14volt transformer (>1500 ma rating) and test the unit with it.
Thanks for pointing out. You might be right. Here is the pic.
 

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arunlouie

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Found an old adapter with trafo inside. Checked the units came out 14.5v and 3 amp direct from the trafo? Attached pics. Will this be good? Connect direct from trafo?
 

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raghupb

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Just write to Schiit and ask them.
They are very responsive and will understand your predicament.
Cheers,
Raghu
 

arunlouie

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I finally connected the transformer directly to the amp. It worked. Currently I am listening to it. Thanks vizeta and others!! Much appreciated!

One simple information missed took many days to get it fixed.
 

vizeta

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I finally connected the transformer directly to the amp. It worked. Currently I am listening to it. Thanks vizeta and others!! Much appreciated!

One simple information missed took many days to get it fixed.
I am glad that your amp is working fine. I would still suggest you to confirm if the transformer is providing enough current to the amp. If current rating is of the transformer is low, you will not get optimum performance (specially when driving your headphone).

Can you please share how you measured the current rating of the transformer (MM is in series when a load is connected or its shorted). the 2nd method is not the right way to determine the current capacity. Please refer this

Also please check the transformer's O/P voltage when it is connected to the Amp. We need to see output voltage drop when Amp is being utilised. (drop should not be more than 10%)
 

arunlouie

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Yes I will do that. I understand how to check the current.. But creating right load need to see how to do. Also for voltage drop I already thought of this, but not sure how to mimic to do the measurement.
 
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