2nd OSC always out of tune, help!

[Giuseppe]

hello to all,
i have a problem with 2nd oscillator tune on my LP SE, but i don't know if this is a real problem or it is only in my mind (it's my first analog synth!).
Ok, let's go to explain what it happen: i select preset calibration (preset #00), set the osc2 level to maximum and play a note on the keyboard.
Now i can hear that the 2nd osc is not in tune respect to the 1st one, it's slightly over.
So, to reach the unison i have to adjust the frequency of the 2nd OSC rotating the potentiometer to the left (until in precision mode i have a value of 2023, while it should be 2048, corresponding at the center of the potentiometer).
I've tried to tune my LP several times since i bought it (used), but even after calibration, 2nd osc is never in tune.

Today, after some months that i didn't turn on my LP, after warm up of about 45 min, i noticed that autotune mode was not be able to reach the value of 60.00 at C3, it stopped at about 59.75. So i decided to calibrate pitch wheel, 2nd osc, and all notes range. After tuning procedure all ok about 1st OSC, but not the 2nd.

So, have my LP some problem on 2nd osc, or it's a normal behaviour?
Can someone verify if have same problem or not?
I have to send my LP to service lab (warranty is about to expire, grr)?

Thank you for help, Giuseppe.

[Dannymon]

I have the same problem....is this problem present on all LPs or is it just a few???............Everytime I'm going to use the LP, I have to leave on for about 30 minutes until the oscillators heat up, then the oscillators are back in tune. Is there a way around this?

[Amos]

Danny, if everything is in tune after a 30-minute warm-up, then your LP is working perfectly. Please note that the Note Calibration instructions ask you to leave your LP turned on for at least 30 minutes before running the calibration. That's how long it takes for the unit to reach thermal equilibrium, which is required for correct tuning. The instrument is alive; the oscillator tuning depends on temperature... there's no way to use this analog VCO design and not have to deal with temperature-dependent tuning one way or another. It is a part of the basic physics at work within the components.

So, if you leave your LP on for 30 minutes and the oscillators aren't in tune, it's a problem... if you first turn on the synth and the oscillators are out of tune, but they converge on (and remain in) correct tuning, that's analog!

Your LP is just reminding you to take it slow and enjoy life. In my studio, I turn on the analog synths first... then the computer... then I make myself some tea and sort out what I am going to do, maybe audition some samples... and by the time I'm ready to use the analog synths, they are ready to go.

Cheers,

Amos

[Dannymon]

Hi Amos, Thanks for your reply...I kind of knew that you had to allow the oscillators to heat up, but somehow I thought that with the Auto-tune feature turned on, this wouldn't be an issue because the tuning system would tune the oscillators even right after turning on the LP. Would this be possible?

On a side note.....you are right about taking life slow....good advise. lol

Thanks

[Voltor07]

I usually surf the web while waiting for my LP to warm up. It's a good way to find inspiration for whatever I need inspiration for.

[dlearyus]

i NEVER surf the web on my DAW....16 hour reloads aren't fun at all ;)

Cheers ;)

DL

[Amos]

somehow I thought that with the Auto-tune feature turned on, this wouldn't be an issue because the tuning system would tune the oscillators even right after turning on the LP.

Auto-tune will tune oscillator 1 to be in tune faster than it takes the whole synth to warm up, but in order for both oscillators to track in unison across the whole range of the synth, it needs to be at its full running temperature.

[Dannymon]

Ohh I see....Now it makes sense.....Thanks Amos

[goldphinga]

Ive got an LP tribute, and OSC 2 doesnt seem to accurately remember the stored detune value. Any ideas whats going on? Osc 2 always seems more out of tune than the stored value if that makes sense!

Any ideas?

[praxisaxis]

The second oscillator is subject to variations in tuning exactly the same way as the first. The way to deal with it is to let the instrument warm up (about 10-30 mins), then manually tune the oscillator using the osc 2 pitch variable (on the front panel). If you save your patch at that stage, then it will be in tune next time you load it, given that you allow the synth to warm up.

Having said that, both oscillators have minute fluctuations in pitch between uses, warm or not. If you're not keen this sort of thing, you should stick with digital synths, and stay away from analogue synths (and acoustic instruments).