What's Best Care for Piano Black Finish Speakers?

My wife has a high gloss finish Yamaha piano, and has followed these instructions for many years with great success:

"The best approach is the least aggressive approach."

High Polish Polyester Finishes:
• Everyday maintenance - lightly dampen cloth with water, carefully wipe piano and follow with dry cloth.

• Greasy Fingers & Dirt - lightly dampen cloth with dish water solution, carefully wipe piano and follow with dry cloth.

•Occasionally - use Yamaha’s Extra High Gloss Polish, do not spray near strings.

When cleaning, she first uses a feather duster to remove surface dust (since the dry dust is abrasive). A soft, clean cotton cloth is her cloth of choice, and she always uses straight strokes, not circular motions. For the "dish water solution" she uses a very light solution of of Ivory Liquid dishwashing liquid detergent and water. Applying the Yamaha Extra High Gloss Polish is something she does only once per year or so (this polish leaves very little to no residue).

My sugestion is similar to Rushton's.--Getting rid of the dry dust first---Then Glass Plus is as good as it gets. NO STREAKS.---Spray the soft cotton tee shirt; not the speaker.Turn the rag after doing one side to dry that side---This I find is much better than plain Windex. The tops are the only side where you have to worry about dry dust.You can blow that off with your breath.

I have used this product on my Definitive Piano black gloss caps to Kharma 3.1 speakers to the acrylic platform on my Basis turntable. Polish with "Zymol" which is made for clearcoat car finishes and will not scratch or leave swirl marks and actually removes them leaving the finish smooth to the point where dust does not settle and if it does can easily be removed. Plus it will bring back older finishes to near new and keep new finishes, well new . I put on a couple of coats maybe twice a year, cleaning between wax with a soft dry cloth or with windex for the flat surfaces where dust would settle.

I second George - Glass plus works great on my pioneer elite TV.