I was looking at a 2nd hand KR 103 to buy. If while playing notes the damper pedal is pressed all sound is muted. Is there a function switch or something that needs swiching on to get it to work? The owner is a school.... no one there knows how it works.

First you need to make sure that the keyboard is programmed to accept the DP-10 as factory default and then that the DP-10 is working perfectly. There is a case where the DP-10 action switch is activated directly, in this case the sustain does not stop and you need to change the micro switch of the DP-10 pedal. It has already happened to me and I replace it by adapting another micro because Roland does not support you and wants you to buy another DP-10.

I know nothing about music, and I don't play piano, but I have played with these when they first came out. I was manager of a public hall and a shop brought a load of them for demonstration. It sounds like an Effects setting and I know that is one called 'Leslie', which if I remember correctly is the effect of a speaker spinning in a speaker enclosure.

Here is your manual

http://www.synthmanuals.com/manuals/roland/kr-3500/owners_manual/kr-3500_om.pdf

Service Manual and a link to Roland, to ask them direct.
Roland KR-3500 Service Manual, Analog Alley Manualswww.analogalley.com > osccart > product_info
Product: Roland Digital Intelligent Piano, model KR-3500. Service Manual , First Edition. Contains/Contents: specifications location of controls

Support - Manual Archive - Rolandwww.roland.com > support > manual_archive
HP-3500S Owner's Manual · HP-3800 Owner's ... KR-1070 Owner's Manual · KR-117 Owner's ... KR-4500 Owner's Manual · KR-4700 Owner's Manual · KR-4700 ...


Roland USA
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US
Phone: 323-890-3700
Fax: 323-721-4875

Thre is a sustain pedal jack next to the foot switch jack. The pedals used are different. The foot switch is a latching switch, the sustain pedal is a momentary.

Is this the correct sustain pedal for this unit? It sounds like it should be a momentary button type. I would look into that. Some have a push to work type of switch and some use momentary. If it is, I would open that pedal and clean the switch with contact cleaner, as it appears to be sticking.

every sustain pedal got different polarity.. normally just go to global setting on your keyboard and change damper polarity setting to plus or minus (select which one work with your sustain padle).

1.Make sure you are plugged in to DAMPER (not FC1 or FC2) 2. Check to see if the notes STOP sustaining when you PRESS the pedal. If that is the case, first try turning off the Roland with the pedal plugged in and restarting with the pedal pressed down. 3. Press the EDIT button and scroll to Damper Polarity. See if it's set to Standard or Reverse. 4. If problem persists after all that, try holding the pedal jack into the Roland at different angles and then try the same with where the cable connects to the pedal. At that point, you can either attempt to repair the pedal or get another one.
Hope this helps, Stewart

Have a look in your manual at the sections on Note Repeat and Time Division.NOTE REPEAT] – Holding this button while
striking a pad causes the pad to retrigger at a
rate based on the current Tempo and Time
Division settings. The Note Repeat feature can
be synced to an internal or external MIDI Clock
source. [NOTE REPEAT] can function as a
latching or momentary button
19. [TIME DIVISION] – This button is used to specify
the rate of the Note Repeat and Arpeggiator
features. When [TIME DIVISION] is activated,
you can press one of the 8 switches to specify a
time division. [TIME DIVISION] can function as a
momentary or toggle button.
Please note that while [TIME DIVISION] is active,
the 8 assignable buttons will not function as MIDI
CC or Program Change switches until [TIME
DIVISION] has been de-activated.
20. [ARP ON/OFF] – This button enables and The manuals and updates can be downloaded here:http://www.akaipro.com/mpk49 Please let me know if this helps.

There are two types of damper pedal switches, on that is closed until you press it, and one that closes when your press it. It sounds like your Casio is expecting one type and your Roland pedal is the other type. A quick way to test this is to plug a guitar cable into the Casio pedal input and see if the keyboard sustains. If it does, then your Casio requires an "normally closed" switch.

Some pedals have a small switch near the cord or even on the bottom of the pedal that will reverse the switching operation (BOSS pedals, a division of Roland, have this feature). If you can find that, then change the switch position and you should be OK.

If not, and you feel like digging into your pedal, you could take the bottom off of the pedal and check out the switch itself. Many pedals use a switch that can be used either way. The clue will be on the switch itself. If there is an extra tab on the switch that is unused, then switch the wire that is furthest away from that tab to that tab. This will probably involve soldering, but it is nearly impossible to damage anything.
If moving the wire that is furthest away does not do anything, then try putting that wire back and switching the other one.

If your pedal does NOT have an extra tab, you're SOL, unless you want to buy a replacement switch (unsure of make). If this is the case, you are probably better off getting a different damper pedal - preferably one that is marketed as "universal"

Sell the pedal and get a digitech, or convert it into a looper pedal.

what is make and model? I have owned several keyboards, with 2 of them Korgs in which I would connect a damper pedal. I noticed that when I help down the pedal, after so too much input within the cpu of the keyboard, it would 'short-circuit' and sound like I had played an 'off-key'

If you have been using the damper pedal, and even if you release a little on up on it, but not all the way, the 'off-keys' will still sound. I must always make sure the pedal is placed in a position that my leverage action of my foot will completely 'release' the overtones still being processed by the keyboard (whether they're audible or not)