McDSP Synth One TDM/RTAS difference

[Stig Eliassen]

I've demoed this synth using the TDM version, and today I decided to switch to RTAS. The timing accuracy sucks! Up to 41 ms late compared to the TDM version, and not consistent either.

Anyone else seen this?

[Eric Lambert]

Originally Posted by PT Lover

I've demoed this synth using the TDM version, and today I decided to switch to RTAS. The timing accuracy sucks! Up to 41 ms late compared to the TDM version, and not consistent either.

Anyone else seen this?

Delay compensation should make them the same. Something's not right.

[Stig Eliassen]

Delay compensation should make them the same. Something's not right.

Well, it doesn't. I made two stereo audio tracks where I, with ADC on, printed one RTAS version and one TDM version. TDM was nice and tight, but RTAS was late and sloppy.

I tried different things like toggle ADC on/off, duplicate the instrument track, de-activate/re-activate the instrument track. Nothing made it better.

[Stig Eliassen]

I've now tried importing a synth track (TDM) into a new session, and it sounds fine. Switch to RTAS - disaster.

Also tried with a new track in a new session. TDM is fine, RTAS is not.

I've contacted McDSP support.

[mcdsp]

Howdy everyone,

about the response from McDSP's Synth One TDM vs. RTAS version...

I assume you are talking about when you play a note, and see the actual audio output from the synth. If I am not understanding something correctly please let me know.

For said playing response - yep, TDM is pretty darn consistent (and fast!). RTAS - not as good - acknowledged. If you are using large buffer sizes (1024, 2048, ...) the 'note playing' part of the synth engine may get stalled - causing the performance you are observing.

There have been a few changes to Pro Tools since Synth One was released, and in particular in Pro Tools 8.0. There might be some new SDK features we could take advantage of, however that is not planned in our upcoming release. I can certainly put the request in the engineering queue for the next release.

But in general, what you have observed is why there is a TDM version in the first place - low latency and little CPU hit.

Thanks for checking out McDSP plug-ins!

Colin McDowell

[Stig Eliassen]

I assume you are talking about when you play a note, and see the actual audio output from the synth. If I am not understanding something correctly please let me know.

That is correct.

For said playing response - yep, TDM is pretty darn consistent (and fast!). RTAS - not as good - acknowledged. If you are using large buffer sizes (1024, 2048, ...) the 'note playing' part of the synth engine may get stalled - causing the performance you are observing.

I use a buffer size of 1024 for this session since it's so many VI's involved. I actually can't say how the synth performs with a lower buffer since I didn't switch to RTAS until many VI's were in session, but still...it should work just fine.

There have been a few changes to Pro Tools since Synth One was released, and in particular in Pro Tools 8.0. There might be some new SDK features we could take advantage of, however that is not planned in our upcoming release. I can certainly put the request in the engineering queue for the next release.

I'm on 7.4, and I certainly don't expect any miracles.

Thanks for chiming in, Colin. Much appreciated.

[Eric Lambert]

So this is in reference to live playing.

Just about any RTAS instrument will exhibit a delay when playing live, but that should be compensated for during playback.

How about recording with the TDM version then switching to RTAS after recording is finished?

[Shifted Music]

Originally Posted by Eric Lambert

So this is in reference to live playing.

Just about any RTAS instrument will exhibit a delay when playing live, but that should be compensated for during playback.

How about recording with the TDM version then switching to RTAS after recording is finished?

I have found the Synth one plug to be very inconsistent in RTAS.

with a fast attack percussive sound the amount of latency seems to move randomly. i did some testing a while back and every one of 5 successive recordings were in a different place. Thats plus the fact that some of the plug in settings cause my computer to crash (verified by colin as a bug in some of the settings)

I stopped using it. Pretty lame for something I paid for and I think is a great synth...

[RussUK]

Originally Posted by mcdsp

Howdy everyone,

about the response from McDSP's Synth One TDM vs. RTAS version...

I assume you are talking about when you play a note, and see the actual audio output from the synth. If I am not understanding something correctly please let me know.

For said playing response - yep, TDM is pretty darn consistent (and fast!). RTAS - not as good - acknowledged. If you are using large buffer sizes (1024, 2048, ...) the 'note playing' part of the synth engine may get stalled - causing the performance you are observing.

There have been a few changes to Pro Tools since Synth One was released, and in particular in Pro Tools 8.0. There might be some new SDK features we could take advantage of, however that is not planned in our upcoming release. I can certainly put the request in the engineering queue for the next release.

But in general, what you have observed is why there is a TDM version in the first place - low latency and little CPU hit.

Thanks for checking out McDSP plug-ins!

Colin McDowell

Whatever anyone says, I do appreciate this kind of immediate, honest and thorough response from a vendor. Thanks Colin.

[Stig Eliassen]

How about recording with the TDM version then switching to RTAS after recording is finished?

I've tried this too and it doesn't work. The RTAS version isn't usable at all for me. TDM is fine.

with a fast attack percussive sound the amount of latency seems to move randomly. i did some testing a while back and every one of 5 successive recordings were in a different place. Thats plus the fact that some of the plug in settings cause my computer to crash (verified by colin as a bug in some of the settings)

Thanks for chiming in. That's good to know.

Whatever anyone says, I do appreciate this kind of immediate, honest and thorough response from a vendor. Thanks Colin.

I agree 100%.