Ardour and Hydrogen sync

Hi! I’m having trouble with sync.

The bright green JACK button is lit in the top left of ardour in my session. The song is one in which I’ve derived the tempo by using shift-drag to align bars with the kick drum on the “1” in the drum track, and the resulting weirdo tempo is 149.803. If I go to start of session, and press play, both ardour and hydrogen will do exactly that. (Well, Hydrogen can be coaxed into starting on cue). Hydrogen has stored 120 as the tempo for its drum program, but it quickly picks on to my weirdo tempo, and displays 149.80 after this happens. Things sound great and synchronized for bars 1 - 4.

However, although as far as I can tell visually that Ardour’s wave forms are aligned with bars, Hydrogen lags, and after 18 bars sounds as if it’s 180% out of phase. After 36 bars, it has lagged so far behind that the snares of both programs are aligned again.

In session/properties, I see that Ardour is the JACK Time master. In hydrogen, the “J.TRANS” button is lit, the “J.MASTER” is not. Hydrogen is in song mode. I’ve experimented with reversing the above to make Hydrogen the master, but then I get even worse results.

Can anyone advise? Until now, I’ve had good luck with sync between these two programs as far as I can tell. What’s new is the fact that I’ve used shift-drag to align Ardour’s bars to beats if that’s of any relevance. Thanks!

I noticed some release notes for Hydrogen 1.0.1:

Fixed jack transport tempo drift when using non-integer bpm values

I have 1.0.0-rc1 and a non-integer bpm.

Maybe this will be useful to someone else.

This isn’t a solution directly, but you could try using DrumGizmo. (start – DrumGizmo Wiki) That way you’ll have a drum machine that works inside of Ardour, without sync issues. I use it. It’s actively maintained and they even have an IRC channel for support.

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