If you can find one, the Roland EV-7. Nice long throw like the FC7, has a 10K pot that is required by Kurzweil and the plug is tip/sleeve is Kurzweil compatible, not backwards like the Yamaha. Con, it is expensive and hard to find. The EV-5 is a POS.....

Delaware Dave,

Thanks. I'll check it out if I can find one.
Guitar Center might have it.

Ugh.
It's turning in to the Radio Shack of the MI industry.
All the money is in accessories, sticks, picks, kazoos, mini keys.

A may have to just order a bunch from Sweetwater and send back what I don't keep.

John

Edited for spelling

Another alternative is the Boss FV 500L. It is compatible. The only con (for me) is the throw isn't as long as either the FC7 nor the EV7.

http://www.bossus.com/products/fv-500h_500l/

Be sure it is the 500L (low impedence) required by Kurz and not the 500H.

Hi,

Please read this as well:

http://kurzweil.com/knowledgebase/forte ... llers/428/

I'm using two Yamaha FC7’s on my Forte.. The FC7 is built like a tank.. I have one from 1987 that's still working fine! I've stopped using Yamaha kit after their CP250 back in 2006. I rewired them to suit Roland's standard (tip is wiper) this also happens to be the same as Kurweil's standard. The modified FC7s work very smoothly on the Nord Ne373 and NS2 and on Roland's RD700SX/GX, RD800 and on Roland's Juno Di and on Midi Solutions cc box. They work quite well on the Forte but I'm not convinced the Forte has a proper log law audio taper translator. None of the modes available on the Forte really gives a nice smooth volume transition.

I suppose it might be the FC7 pot resistance value doesn't suit the Forte's cc input so well, or that Kurweil use a log pot?

Ahh.. Just read the Kurzweil requirements linked in the post above! That's interesting.. So Kurzweil state that the FC7 has a log law (audio taper) pot. I must test this out, because if it's right then Roland's expression pedals will be the same. Ie not work smoothly on the Kurzweil. Simply because the rewired FC7 does work very well on Roland's gear.

Here are the results of my tests:-
Aside from the ring/tip switch over, both the Roland EV5 and the Yamaha FC7 swell pedals have linear pots. The EV5 has a 10K pot and the FC7 has a 50K pot. Both are also clearly marked with the symbol B denoting that linear track. The input impedance of the Kurzweil’s CC pedal circuit is low enough to load the 50K linear pot so it makes the FC7’s pedal response appear logarithmic (all the action appears squeezed up towards the toe down position).

Replacing the FC7’s pot with a 10KB equivalent is not trivial. The pot is specially made to suit the pedal’s design. It is a miniature pot, with a case that’s 16mm in diameter, a 5mm diameter shaft with a D type flat, a 7mm diameter threaded shank and location dowel that is specifically oriented to correctly engaged the pedal sweep with the pot’s resistance range. The pot’s resistance track has a 90degree / quarter turn full range sweep. Space is at a premium inside the FC7’s case so replacing it with anything else is fraught. Luckily I had an old mod wheel assembly from a DX7 with a physically similar 10KB pot that had the right quarter turn sweep range. Even with this it was not that easy to fit it.

Having replaced the pot the FC7 now works much more smoothly over its entire range on the Forte.

Conclusion: Modifying the FC7 is not something to consider unless you can get the right 10KB pot! Although the FC7 with just the switched ring/tip connections, isn't perfect, it does work reasonably well.

I ended up getting the Boss FV-500L.
It's big and a bit heavy but it's very solid.
Being able to adjust the the clutch is a huge bonus as it keeps
the accidental kick flops from happening.

John

This is an oft had debate and it's still not possible to get a universally accepted answer. Last year I paid my tech guy considerably more than the FC-7 cost to take one apart and try to find out about replacing the 50k pot with a 10k one. Having measured the responses and looked at the midi data, he reported that if you swap the wiring on the plug of the FC-7 then to all intents and purposes it has the same response as a pedal with a 10k pot. I have to say that I have found this to be the case in practise as well. It plays very smoothly and seems very linear to my thinking. I have slightly modified the scale to 102% and taken 2 off the value in the zone settings. I think that has been necessary due to the messing around the guy did with the pedal which involved drilling out the mounting so it may not have gone back quite in the right place. I love how the pedal feels though and don't feel the response is squeezed up one end as the previous poster says. I guess it's down to individual preference and the confidence you have in it.

The issue I had with the FC7 (others have also reported it) is that occasionally it would send the PC3 into restart upon touching the pedal. I was at a gig and it started doing it. In between sets I disconnected everything from the PC3 except the FC7. As soon as I touched the pedal the PC3 would recycle. So I bought another FC7 and the new pedal did the same thing. It did it with or without the ashby adapter. Then it would work for a gig or two then start the recycling process. I contacted Jean about the issued and he advised using an expression pedal with a 10k pot. I purchased the Roland EV7 because kit was 10k, didn't require an Ashby adapter and had a long throw like the FC7. I've been using that pedal for 3 years and never had the restart experience. I went back to the FC7 and within a couple of gigs the restart issue reappeared, both with the old FC7 and the new FC7 so I have had to abandon the use of that pedal.

I recently found another pedal that is 10k, Kurzweil wiring compatible and has a long throw, but is expensive. It is the pedal designed for the Crumar Mojo.

http://www.crumar.it/?a=page&p=accessories#p27

The issue I had with the FC7 (others have also reported it) is that occasionally it would send the PC3 into restart upon touching the pedal. I was at a gig and it started doing it. In between sets I disconnected everything from the PC3 except the FC7. As soon as I touched the pedal the PC3 would recycle.

Wow! That's a bit of a nightmare. Live with flaky kit is absolutely a no no! Using my two 50k standard FC7’s with switched ring/tip on the Forte hasn't produced a full on system restart. Thank God! But I have noticed that later into a gig, typically during the second set, sometimes the pedal response can get more extreme. That is more like the Forte is starting to interpret the pedal's output as more logarithmic rather than linear.

My view of this is it's quite likely these sorts of 'side effects' may happen because the pedal as it stands is outside Kurzweil's spec'd requirements. I'd guess the firmware is not as defensively programmed as it might be to handle these problems, hence causing the restart.

It's a bit like expecting a Midi Solutions box to work with a Nord.. Neither properly support the Midi electrical standard. Nord doesn't run it's midi out at 5v and Midi Solutions expect to be able to power their boxes with the 5v normally available at the midi in. Gotcha!

Trouble is there isn't a universal pedal standard! Mind you even if there was there'd still be someone tying to beat it!

I see no reason why Kurzweil should not be able to accept a range of expression pedal pot values from 10k to 50k, either log or linear. 10k pots are extremely hard to find with a long sweep and they are expensive. The only two I found that meet the spec AND provide a long throw are the Roland EV7 (NLA) and Crumar's long throw pedal. There are a sizable number of 10k pedals on the market but the throw is too short to properly control organ playing. The Boss FV-500L is certainly solid and works but the throw is too short to properly control organ (IMO). The nicest one is the Yamaha FC-7, nice long throw, built like a tank and can be obtained for under $40 new but unfortunately has a 50k pot that my PC3 doesn't seem to like at all. The Yamaha reverse wiring issue is a non-issue; I built an adapter in under 10 minutes for it. The real issue is the pot and how the Kurz responds to that pot. Jean mentioned something to me regarding the math, stating ".. the system was devised to work with a 10kΩ pot, not a 50kΩ. So in effect you have changed one of the variables in the 'equation' so the results will be unpredictable to an extent ..". Also, I'm assuming (maybe wrongly) that since you are dealing with voltage (5V) with an expression pedal that this can add to the unpredictability given variable electrical conditions. The problem that I mentioned above never happens at home/studio where the electric is stable, only when I'm doing a gig where electricity and electrical wiring can be unpredictable and apparently compounds the issue. The Roland 10k pedal has never created a restart of the PC3 either at home/studio or at a gig. One minor issue with the EV-7 is that although I get a linear response, the pedal maxes at 122, i.e. it won't go the full 127. I went into Control Setup #126 and set add = 5, so the pedal's response is now 5-127. For each setup I have to remember to add 5 to each layer's CPEDAL menu.

The electric characteristics of the Kurzweil input are fixed, unfortunately these interfere with the correct interpretation of the FC7. But all could be remedied by a pedal setup routine. This program would be part of the Kurweil's tool box. It would provide a calibration service that take the user through the pedal's full range of ADC readings and assign zero to the lowest reading and 127 to the highest. It would also provide for the selection of an offset table to flatten out log tapers. Most digital synth pot reading ADC's are at least 8 bit, so the translation from 256 levels to 127, even when the 256 levels are not all present (due to limited pedal range) or a bit wonky (due to non linear effects caused the pot or the interface) should be fairly good.

This calibration would ensure your pedal gave the maximum range in as near linear spread possible. I think M Audio's midi keyboards provide a similar pedal calibration routine.

The reset caused by combination of FC7 and glitchy power, is interesting.. Putting 2 + 2 together and making 5! I wonder if the lack of the correct load (10k) is allowing electrical noise at the ADC input or at least into the system's circuit board? Adding a decoupling capacitor to the FC7's pot of say 0.1uf from wiper to shield might help.

If you want to use a Yamaha FC7 pedal with a Kurz, polarity issues aside, all you really need to do is apply Thevenin's Law and put a 12K resistor in parallel with the pot to give it an effective overall resistance of 10K.

Forget about trying to find and swap out pots. This is a simple mod where adding a parallel resistance to the external circuit gives the thevenized circuit an effective total resistance of 10K ohms.

This is determined by the equation 10K = 1/(50k)+ 1/(x)

Solving for x gives x=12K

Here's the circuit diagram assuming the Tip, Ring and Sleeve connections are compatible with the Kurz.

Actually I'm kind of amazed I've never seen anyone offer this solution before. Any 1st year electronics student could do this.

Gary

Ehm!... The modding solution Gary proposed is fine, and the 12K is also fine, but the correct equation is
1/(10K)=1/(50K)+1/x

Actually, we're both wrong.

The correct equation is

Formula:
Rtotal = R1×R2/(R1+R2)

Where Rtotal is ~10K, R1 = 50K and R2 = X

Sorry about that. Old age and calculators have softened my brain

Gary