Greetings,

I'm a huge fan of FM synthesis. It's really interesting whenever I learn more about Yamaha's history and songs that were recorded using FM synthesis.
I have been a Reface DX owner for almost two years now.

The most popular thread in this subforum is a Reface DX feature request thread.
Some of the suggestions, while awesome, would be cost/time prohibitive to implement.
Ultimately the question becomes, "Is it worth doing?".

I do have a request that would be worth doing both for Yamaha and Reface DX owners. I'm speaking of LFO sync.
I'd like to claim that LFO sync is a feature on every single previous Yamaha DX synth, but that would be disingenuous of me, the DX9 does not have that feature.
I can say with confidence however, that every 4 operator and 6 operator FM syth released by Yamaha after the DX9 does in fact have that feature.
Until we get to the Reface DX.

Why Is LFO sync important to the architecture?

From the DX 100 and DX 21 Manual:

"The beginning of the LFO cycle is normally synchronized with key-on timing. This parameter lets you turn this synchronization ON or OFF.
All operators are affected simultaneously. When this parameter is ON, the LFO cycle will always begin from the peak of a positive half-cycle (90 degrees phase angle) when a key is played. This produces a clear, consistent attack on all notes.
When the LFO KEY SYNC is OFF, the LFO cycle starts from a random point when a key is played.
This is an ideal setting when the LFO is being used to create natural-sounding chorus or phasing effects."

In short it allows for consistent rhythmic pulses on key presses.

A company might be willing to grant a feature request, but then the question is, "where do we stop?".
It threatens to become a slippery slope, and at the bottom of that slope is a large pile of features that every customer wants.
There are certainly other features the Reface DX lacks that most other DX models have. Many of them are performance controls.
In my experience, there are usually work arounds like external midi controllers.

I can't quantify the value of adding LFO sync. But I can certainly show it's not useless.
There's what Howard Massey calls "far and away the most inconsequential of all the edit parameters",
Oscillator Sync. You would be hard pressed to find someone who is clamoring for that feature.
Ironically it's present on the DX9 when LFO sync is not.

I'd love 128 patch memory locations, polyphonic portamento, delay effects synced to tempo, etc. but I know those can all be worked around and will not impact the sound my DX can produce. LFO sync there's no work around/replacement that I have found.

Features aside, Yamaha can be proud that the Reface DX sounds as good as its predecessors, because it does.
The Reface DX however, falls a little short of allowing for some of the sounds that can be created on previous 4 operator synth models such as the DX100, DX21, and DX11.
I believe patching in LFO sync can rectify this.

I realize that this isn't a trivial change, and there are significant costs involved. I had a long list of suggestions on how Yamaha could implement this with the minimum level of effort, but instead I'll just trust Yamaha to do what it does best.

Thank you for your time