Print Page - CPC 664 sound problems

Title: CPC 664 sound problems
Post by: Fer on 08:38, 04 June 17

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 :)

Title: Re: CPC 664 sound problems
Post by: VincentGR on 19:57, 05 June 17

Is white noise permanent?

Title: Re: CPC 664 sound problems
Post by: arnoldemu on 20:22, 05 June 17

internal speaker only or also on stereo sound output?

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

Title: Re: CPC 664 sound problems
Post by: Fer on 12:45, 06 June 17

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 ...

Title: Re: CPC 664 sound problems
Post by: Bryce on 13:05, 06 June 17

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.

Title: Re: CPC 664 sound problems
Post by: VincentGR on 13:38, 06 June 17

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 :picard:

Title: Re: CPC 664 sound problems
Post by: Audronic on 13:47, 06 June 17

@Fer (http://www.cpcwiki.eu/forum/index.php?action=profile;u=2215)

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

Ray

Title: Re: CPC 664 sound problems
Post by: Fer on 15:25, 06 June 17

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

Title: Re: CPC 664 sound problems
Post by: Fer on 15:36, 06 June 17

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 :)

Title: Re: CPC 664 sound problems
Post by: Audronic on 23:59, 06 June 17

@Fer (http://www.cpcwiki.eu/forum/index.php?action=profile;u=2215)

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

Title: Re: CPC 664 sound problems
Post by: Fer on 07:41, 08 June 17

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

Title: Re: CPC 664 sound problems
Post by: BluesBrothers on 19:46, 08 August 17

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

Title: Re: CPC 664 sound problems
Post by: Fer on 19:42, 15 August 17

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 :)

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General Category => Technical Support - General => Topic started by: Fer on 08:38, 04 June 17