Sound level problem

[cobra]

Hey guys
My name is Franz, I live in Switzerland. I've been following you for a few years but I've never written anything, due to my little experience.
I write because I also have a problem.
I have an M100, it worked till end of July. Back from vacation a set of tones feels very weak (on all drawbars)
The tones are from 49 to 91.
I tried to change the 12AX7 tube but to no avail.
Do you have any ideas?
Thank you
p.S. sorry for my bad English

[enor]

So all the frequencies below 49 have normal volume?

Are all remaining notes playing in their normal range, or does the entire organ appear to have dropped down an octave?

[cobra]

Hi Henor
Thanks for answer.
Yes, all notes below 49 have normal volume.See the attached picture the yellow painted notes sound normal, all the others very weak
No, It seems all notes playing in their normal range.

[enor]

Frequency 49 thru 91 are the frequencies which have capacitor based band pass filters on the tone generator; the lower ones have simpler filters. Sometimes when you start the organ you can get a "false start" where the organ spins an octave too slowly. This makes the capacitor filtered ones drop considerably in volume because the notes, being an octave too low, get taken away by their own filters. But if this was your problem, all notes would be an octave too low, and your vibrato-chorus would sound weirdly slow.

Such a false start is a very common occurance, especially if the organ has been parked for a while and maybe not oiled in a while either. And since ALL notes 49 and up are affected by your problem, I really can't think of another cause ... Double check! Sometimes it's not obvious to an inexperienced ear that the thing is running slow; but once you've heard it once you'll immediately recognize it afterwards; it is a very characteristic sound

[cobra]

Yes, the M100 was stopped for about 3-4 months during the summer.
When I resumed it last month, the starter made a few turns and stopped when I started. So I started the vibrato scanner by turning by hand the synchronous motor.
I still oiled the generator and ran it all day and it's been 3 weeks but with no positive results.
Should I change the starter motor? What else can I do?
Yeah, probably the notes that feel good are one octave lower, you're right.

[enor]

Start problems are very rarely due to a motor fault. The most common causes are (in order of probability):
1 Sluggish generator due to oil starvation
2 Stuck bendix gear in the generator (on the main shaft, the gear that the start motor is supposed to engage to when activated. this gear is supposed to be able to slide freely back and forth on the shaft)
3 Faulty Run switch (yes, the RUN switch, not the start switch)
4 Faulty Start switch
5 (Bad motor) - I've put this one in parenthesis, because it's the only one out of the above that I've never actually encountered so far.

[tmccann]

Frequency 49 thru 91 are the frequencies which have capacitor based band pass filters on the tone generator; the lower ones have simpler filters. Sometimes when you start the organ you can get a "false start" where the organ spins an octave too slowly. This makes the capacitor filtered ones drop considerably in volume because the notes, being an octave too low, get taken away by their own filters. But if this was your problem, all notes would be an octave too low, and your vibrato-chorus would sound weirdly slow.

Such a false start is a very common occurance, especially if the organ has been parked for a while and maybe not oiled in a while either. And since ALL notes 49 and up are affected by your problem, I really can't think of another cause ... Double check! Sometimes it's not obvious to an inexperienced ear that the thing is running slow; but once you've heard it once you'll immediately recognize it afterwards; it is a very characteristic sound

The experience on here and the free advice is tremendous. I have had this issue before with the low speed start, knew the symptom, but not the cause. Thanks!

[johwin61]

Is your run motor still OK?

I had problems starting my A100. It was almost impossible to sync it at 50Hz. Sometimes it synced at half speed. It was caused by one of the two run motor coils being bad. When checking the motor coils with an ohm-meter it measured open circuit. It was really difficult to start the organ with just one of the two run motor coils. Most of the times it started at half speed or not at all.

I repaired the run motor, by changing the coils to new ones. I have 2 more new coils as spares, if that can help you.

But first check that the TG is properly oiled and turning freely!

[cobra]

Hi guys, problem SOLVED!!
It was my fault. I always started the hammond everytime with Run and then START for a few seconds. It always worked, but after the holidays it didn't.
Enor you helped me a lot with this sentence: Sometimes when you start the organ you can get a "false start" where the organ spins an octave too slowly.
Yes! My Start-Procedure was WRONG!
I went to read the manual. Push the "start" switch up and hold it for approximately eight seconds.While still holding the "start" switch, push th "run" switch upward to its "on" position. Hold the "start" switch about four seconds longer and then release it.
This worked for me.
Yes, I'm stupid I know. 😥

[enor]

Well, at least it was an easy fix ;)