Yamaha NS-690 I, Wood discoloration, help?

[Pleyades]

Hello everyone

I have a pair of Yamaha NS-690 I, they have a decoloration in the shape of the front dust cover, I thought it was somethig related with the age and exposition to the light but I've been checking the same speakers on ebay and noticed they have the same issue than mine, does somebody have any advice in how to solve this issue?, I've been checking on google something about mineral oil and beewax I also asked a local carpenter about it and he said something about sandpaper all the body of each speaker but I thinks it's a little extreme, I'm worried abou it because I want to keep the original color because I have a Yamaha amp (CA-1000 III) and if the color change I will have to sandpaper the amp wood top cover too to match the color, by the way I made a test in the top right left of the speaker put in some drops of mineral oil in the clear area but it does not made any change, any suggestions?

 

[Refugee]

Stain makes it darker - oxalic acid (wood bleach) makes it lighter. If there is a clear finish over the wood neither will work well without sanding. you could also mask the dark parts and try some spray lacquer to darken up the light areas and then spray the whole front. Spray lacquer always darkens slightly and there are some colors available - not like paint but like a tinting. Wood finishing is always an experiment for me so take it with a grain of salt. The cabinets can always be fully sanded and redone if your experiments go wrong so if it is really bothering you - try.
In my experience, I have always succeeded but not always on the first try and sometimes it takes more than one method.
Good luck!

 

[amr2]

Light darkens natural wood. It's something normal. If you leave it without grids, over time the color will even out.

 

[Nashou66]

Light darkens natural wood. It's something normal. If you leave it without grids, over time the color will even out.

Yep do this .

Nashou

 

[ignoramustot]

I have a similar issue of grille-shadow on my light-coloured pair of NS-670 ... but I'm not sure if sunlight is going to help with what appears to be a coffee cup stain on the top of one, courtesy of one of the possibly many previous owners... Does sunlight (UV) exposure potentially weaken the driver cones or their surrounds? Where I am down here in Australia, our sunlight tends to have serious UV kick and is a killer for speaker drivers with foam surrounds...