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Diaphragm for Roland KC500 KC550 Speaker D-420

Part Number:D-420ROL
Diaphragm for Roland KC500 KC550 Speaker D-420
SS Audio Roland Speaker Diaphragm D-420SWR
Diaphragm for Roland KC500 KC550 Speaker D-420
Your Price:$16.95
List Price:$24.00
You Save:$7.05


In Stock

Quantity Pricing

  • 2 - 3
  • $16.00
  • 4+
  • $15.00
Roland Speaker Diaphragm Part # D-420ROL
Roland Diaphragm
  • Roland Speaker Diaphragm Part # D-420ROL
  • Voice coil: 1" (25mm)
  • Diameter: 1-3/4" (45mm)
  • Length: 2-7/8" (72mm)
  • Impedance: 8 ohm, DCR: 7 ohm
  • Phenolic dome with copper voice coil on Nomex former.
  • Our most popular replacement diaphragm!
  • Fits most Roland models including:

    Roland: KC-500 KC500 KC 500, KC-550, KC550, KC 550, and many more!

    Please check your model and style before ordering to be sure you are getting the correct speaker diaphragm.
Roland Diaphragm   
4 Stars
Cheap fix for blown tweeter horn
I bought a used KC550 last week and thought it sounded great. Got it home and found a funny sound when I used it with a Hammond XK3 and digital piano. Pulled the horn and sure enough, though it was producing sound, it was not as clear as I knew it should be. I got online and found Simply Speakers was selling the diaphragm for $16.95 and decided to give it a try. The unit arrived this week and I went to install it in the horn. Unfortunately is is not a simple installation. I have a shop and tools but had to create a wider opening in the plastic horn base to accommodate the two connections. Roland had each connection, positive and common on opposite sides of the plastic horn. Once I created the opening in the horn, I only had to make a jumper for the common connection from the amplifier. I tested it and it works great! Just a warning though, that this is not a simple fix for non tech types. Response from Simply Speakers: You have the newer version with the terminals 180 degrees apart. Normally we replace the entire driver for these, but very glad to hear you were able make the new part work.
Did you find this helpful?  1 of 1 Found Helpful
Reviewed by:  from Pennsylvania. on 5/27/2016
5 Stars
Review tweeter voice coil.
Item works perfectly. Had to file one tab to fit the push connector but not a problem. Thanks.
Did you find this helpful? 
Reviewed by:  from Lompoc Ca. on 11/26/2015


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