RMC OPT-01 subsonic filter module for Roland GR-55

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The RMC OPT-01 is a 6-channel subsonic filter module that installs in the Roland GR-55 to eliminate the subsonic over-sensitivity in that unit.

Please note this unit is specifically designed for use with PIEZO pickup systems.  The GK pickups are not piezo and suffer from a different type of interference.   

All international orders are shipped FedEx International Priority and delivery takes just a few days.

Please note, International Order shipping fees do not include import duties or taxes.  
Please speak to local resources to determine import tax rates and information.

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  • 5
    Subsonic filter RMC

    Posted by Alvin on 6th Jan 2022

    Thank you so much. Received package quickly and was easy to install. Keep up the great work.

  • 5

    Posted by Carey L Thaldorf on 29th Nov 2021

    Great service.

  • 5
    RMC OPT-1 Subsonic Filter

    Posted by Marc Cooper on 12th Oct 2021

    AMAZING! a game changer... anyone who has a Roland GR-55 needs to get this; the improvements are SO significant! Richard McClish did a sorely needed fix to the GR-55.

  • 5
    RMC OPT-01

    Posted by Bobby Long on 5th Jul 2021

    This turned the GR-55 from a novelty to a usable pedal

  • 5
    Fast ship. Easy install I would recommend This !

    Posted by Denny C on 31st May 2021

    Fast ship. Easy install I would recommend This ! I have a Godin peizo style. And a GK2 Fender GK ready Strat. I have gigged by being the keyboardist with this. You have to meticulously dial it in on the GR 55.

  • 5
    RMC OPT-01 MK2 FIlter/Buffer

    Posted by The Splitz on 7th May 2021

    The Splitz wish to thanks for the smooth dealing on the OPT-01 MK2. The gen2 buffer has made a world of difference in tracking, especially when running 2 Gr-55's in tandem !

  • 5
    RMC OPT-01

    Posted by Dana Rasch on 28th Sep 2020

    Does what it's supposed to do.
    As a professional jazz guitarist, I found the GR 55 to have such significant tracking challenges that I couldn't consider it much more than an $800.00 toy. The OPT-01 actually makes this Synth usable., and the tracking is reliable enough to gig, or even record with. Roland should have worked out a deal to have this pre-installed instead of giving unwary purchasers the idea that their pick-ups might be installed incorrectly, or that they needed to work with the sensitivity , or worse....that their technique could be the problem.
    all of which occurred when talking with their support. They obviously don't mind wasting people's time in order to profit off of people.
    The installation was not too difficult and they provide a page and some YT links on how to do it, as well as some tweaking advise.
    I was also very impressed at how quickly this item got to me. Thanks for a great product !

  • 5
    Subsonic filter

    Posted by Stephen Russell on 14th May 2020

    This is not a magic bullet, but it definitely improves tracking. I'm surprised roland don't mention it as a retro fit. Very pleased, this ain't t cheap, but where tracking is paramount..........yes!!

  • 5

    Posted by The Judge on 28th Mar 2020

    I've had a Roland Guitar synth for some years and decided to spend some money on the GR55. It is vastly improved over the old models but there are some sounds which just will not play. I found the OPT-1 on line and bought it, had it shipped from the USA (Sweetwater Music..thanks guys). The Price is £210 $, plus $50 for postage. (Fedex and in the UK inside four days.) Then got stung for another £44-50 by the UK customs. It's expensive when you start adding everything up but the bottom line is that it works. It's not perfect but it makes playing the GR55 "awkward sounds" a hell of a lot better. Tracking is greatly improved on the pianos and the saxophones and it's easy to install but you need to be careful removing the ribbon wire connectors and make sure you don't carry a static charge when you do it. Don't hack at it with a knife, tease it loose with your fingers it only takes a little while. Just be careful you put insulating tape over the circuit board to avoid shorts against the metal casing of the GR55 as the provided velcro pad is too small to provide 100% protection. I use an Ibanez guitar retro fitted with the GK 3 pickup. The first rule is. SET YOUR OWN GUITAR UP PROPERLY AND IT WILL PAY DIVIDENDS. Also you need to experiment with the string sensitivity in the GR55. None of my settings are over 27 and many are lower than that. Was it worth it? Yes. Now to midi it to the older synth.......