Hi all!
I would ask if someone knows a way to calculate lfo rate value for a fixed bpm (i mean for example 1/4 note value for 120 bpm). AH of course the phatty is not synced with an external midi clock, otherwise it is simple using CCs. I mean when we are using the phatty’s internal clock. Any suggestion?
thanks in advance!
I am not sure I understand you correctly, but I’ll give it a try …
I assume you are referring to “lfo rate” in terms of a bpm value.
The ‘beat’ in a ‘BPM’ value stands for a quarter note, from what I understand. Of course it can be a dotted quarter too (f.ex in a 6/8 time signature), but I have never seen it being used in that way.
So if you have 120 BPM, we are talking about 120 quarter notes per minute (in a 4/4 time signature that means 120/4=30 bars).
In your example - 1/4-note value for 120 bpm - the LFO rate would be 120 bpm.
If you have 1/16 note value in 100 bpm, the LFO rate would be (100 beats) / (4 quarters) x (16 notes) = 400 bpm.
Or 100 beats x (16 notes /4 beats) = 400 bpm.
1/8 note value in 140 bpm:
140 x (8/4) = 140 x 2 = 280 bpm
Correct me - someone - if you don’t think this is correct.
Thansk for the answere!
Well, what i want to do is to calculate the precision value of the rate knob to have the lfo sync to, let’s say, a quarter note, of an arbitrary bpm.
Now to do that i have to find it manually or by using the tap tempo, but it will never be very accurate. So, there is a way to calculate a precise value between 0-4095 (precision mode range) that will give exactly an lfo rate of 1/4 note of an arbitrary bpm? Hope this makes sense!
Ok, so you want to know the precision value.
Then I guess you have to know how the precision value relates to the lfo bpm value. And hope that it is linear.
Also, I don’t know if there is a ‘global’ relation between these values or if it differs from phatty to phatty due to RAC.
Mayby someone else can answer to that? I’m interested too!
If I remember correct, the Phatty’s LFO is digital. So no RAC here. Correct me if I’m wrong.
Plus I think the control is not linear, provided the range of frequencies.
it’s not linear… if you really want to do this your best bet is to use a frequency counter and a spreadsheet… set a precision value, read the LFO frequency using the frequency counter, then you have one data point. Repeat for evenly-spaced increments of precision value (values 0, 64, 128, 192, 256 etc. would mean taking 64 readings)… then you can plot a graph, and perhaps derive a formula which you can use to calculate the target precision value for a given frequency.
Lastly of course you need to relate frequency to BPM, as Assar explained how to do.
Or, there’s MIDI Sync.. 
Any reason you dont want to use the midi sync feature? The LFO will then reset in time with a midi clock signal… So the rate will be quantized instead of continuous when you turn the knob.
Hi Amos, thanks for answere! Do you know a program or a plugin that could be used as a frequency counter?