Expression Pedal Issue (static) on Allen 632-3D

[SoBeMisha]

Hi Everyone: I've been enjoying my new old organ and most everything seems to be working perfectly. There is one issue that just started--there is static sound and some popping when I use the expression pedal for the Swell/Pedal. It feels like it has less tension than the other two pedals--maybe something is loose. Has anyone experienced this? Any ideas as to the problem and/or solution? Thank you!

[myorgan]

SoBeMisha,

What you describe is fairly common with the ADC organs, but I've never heard of it on a MOS organ before. I'll wait until others can weigh in who have more expertise than I. John (jbird604) is not presently available--gallavanting around the world--but others should be able to help in his absence.

Michael

[Admin]

As the MOS series expression pedals are entirely opto/mechanical with a mechanical shutter controlling the amount of light falling on a photoresistor, it is not likely for them to produce pops and static. More likely the mechanical motion of the pedal is being transmitted to loose nearby wires or connections.

The tension on the expression pedal is adjustable via a screw on the pedal. Again, this adjustment should have no affect on the problem described as it merely adjusts the mechanical friction of the mechanism and has no relation to the audio signal.

[myorgan]

As the MOS series expression pedals are entirely opto/mechanical with a mechanical shutter controlling the amount of light falling on a photoresistor, it is not likely for them to produce pops and static. More likely the mechanical motion of the pedal is being transmitted to loose nearby wires or connections.

Thank you, Admin. I knew it was different, but didn't know how to describe it well. Yours is a perfect description. I should also mention the pops and cracks on the later Allen organs were generally restricted to the Crescendo shoe only.

Michael

[SoBeMisha]

Thank you for the replies everyone. I'm going to try and find time today to take a close look on the inside. I did wonder if perhaps there might be loose wires nearby the pedal. I'll let you know if I find anything.

[SoBeMisha]

Found the issue! One of my used Alesis Nonverbs was faulty--I noticed static on one while making an adjustment. So, switched it out and not more static.

[myorgan]

Found the issue! One of my used Alesis Nonverbs was faulty--I noticed static on one while making an adjustment. So, switched it out and not more static.

SoBeMisha,

Thank you for the follow-up information. I guess that goes to show we really need to check and isolate all devices in a chain before making a determination!

Your issue sounded like the scratchy channel I have on one of my organs. I was thinking connections, etc., but it turned out to be a faulty antiphonal relay--connected to the antiphonal relay, and all is well (if a bit softer) again. I had been blaming the trem units, amplifier channels (and even had an amplifier re-built to the tune of approximately $1,000!=-O). Oh, well--live and learn.

Thanks again for sharing the resolution.

Michael