CPC 664 sound problems

[Fer]

Hi there,


I have a lovely 664 that has the 'white noise' sound problem.  I see that this has been covered before and replacement of the AY chip is recommended.


Am I right in thinking that is has to be a specific model, not the 'A' version that you get in the Spectrums?


I'm struggling to find a replacement, so does anyone know of a good source?  Also, as my soldering is terrible, does anyone on here provide a service for this kind a work?


Thanks all, great site

[VincentGR]

Is white noise permanent?

[arnoldemu]

internal speaker only or also on stereo sound output?

If it's only speaker then that may be broken.

[Fer]

Thanks for the replies


It tends to play white noise instead of the usual square wave noises, but not always.  Some game tunes sound more like quiet popping sounds instead.


The delete beep is white noise.


Tried through headphones, but it's the same I'm afraid ...

[Bryce]

Hi Fer,
    that definitely sounds (no pun intended) like your AY is faulty. Luckily they are readily and cheaply available. Remove the old one, install a socket and replace the AY.

Bryce.

[VincentGR]

I have an issue with white noise too and I did a post for that.
I replaced my AY but there no results, mine does that on my 6128 while loading 128k games 

[Audronic]

@Fer


Does the volume control alter the volume of the white Noise ?


Ray

[Fer]

Hi, yes the volume control does alter the volume.  It's as if everything is normal except the computer is playing the wrong sounds.

[Fer]

It sounds like a very similar problem to this ..
Not sure they managed to fix it or not


http://www.cpcwiki.eu/forum/hardware-related/cpc-6128-sound-problems/


Thanks again all

[Audronic]

@Fer


I could not find a Circuit of the Sound/Tape for the 664 BUT i have a circuit for a 6128.
I hope that this is the same.
Just short out the sound input at the point shown with a 10 Microfarad capacitor to ground an see if the noise goes away.
if it does not then the following Amplifier requires replacement ?
Good luck


Ray

[Fer]

Thanks for that Audronic,  I'll get someone better than me with electronics to have a look

[BluesBrothers]

I'm in UK and can have a look at that for you mate

[Fer]

Thanks mate.  I've been rather busy and only got as far as getting a NOS chip.  I may take you up on that offer if still possible in a couple of weeks