Prosound 1600 amplifier repair

[Wayne Phillips]

This branded amplifier from a well known electronics store came to me for repair.

The fault trying to power up said the owner?

Well on opening it for a quick look I noticed the inrush circuit was missing a inrush ntc to slow the mass inrush voltage.
What they seem to of done here was to add a cap across the relay that is also connected to the primary side of the transformer ie..as the mains power is applied ii feeds one part of the winding then after a second or so the relay clicks over and the cap is to smooth the spark.

Poor idea..so a I have fitted a better inrush device and the amp is back working again.

 

[shrtrnd]

I hope you added a 're-engineering fee' to the final bill.
Good work.

 

[Wayne Phillips]

I hope you added a 're-engineering fee' to the final bill.
Good work.

Yes..the odd think is, why was it such a poor design in the first place?

 

[Harald Kapp]

It's mostly about money saved. Even pennies add up when you sell in masses.

 

[Wayne Phillips]

Just to make folks buy more electronic items when it fails..

 

[Wayne Phillips]

Even the amplifier stage could of done with more devices to cope with meant to be 500w at 4 ohms!

 

[Subaru]

Got a prosound 1600 amp,and the two power needles don't work and the sound is only coming on of one side?what can be done.

 

[kellys_eye]

Got a prosound 1600 amp,and the two power needles don't work and the sound is only coming on of one side?what can be done.

What would you LIKE to be done?

 

[Subaru]

What would you LIKE to be done?

I WOULD LIKE TO TRY AND REPAIR IT

 

[kellys_eye]

Find the workshop manual for it. Post a link to it and/or the schematic for the amplifier.

 

[Dataman]

Hi All
just joined the forum.
anyone got a schematic for this amp?
I‘ve been asked to repair one of these.

 

[Martaine2005]

Hi All
just joined the forum.
anyone got a schematic for this amp?
I‘ve been asked to repair one of these.

Very doubtful one exists, unless someone reverse engineered it and drew one.
But again, doubtful as it’s a cheap Maplin amp.
You might get more help by describing the amps problem.

Martin

 

[Dataman]

Hi Martin
Thanks for the advice. I should receive it over the weekend & will then be able to give a more accurate description of the fault. Pete.

 

[Dataman]

Seems to be the same problem Wayne Phillips experienced a while back, as above.
On power up it’s a 50/50 chance it takes out my 16amp trip. Once successfully powered up, the amp seems to operate without issues. It even sounds better than I was expecting. At this point I have not fully load tested for any significant time period yet.
Wayne, you say “I have fitted a better inrush device and the amp is back working again”
Did you just fit an ntc device in series on the primary side of the transformer?
Regards