Analog Summing in PT Ultimate with working ADC - my Solution
 

I found a solution to "insert" an analog summing mixer without getting sync/delay problems on the DAW return.

What you need:

1. ProTools Ultimate (it must support surround channels)

2. The same amount of interface inputs and outputs (the amount of channels you want to sum up).

I made 3 different routingfolder track presets (one for 8Ch summing, one for 10Ch and one for 16CH) which include everything you need and also a „read me" with instructions. So you can start without reading this whole post. I tested the 10 Chanel Version and it works perfect.

link to my presets:
https://www.dropbox.com/sh/1cd12cdlu...VqH8HH6sa?dl=0


—

This is how it works:

I built 2 surround aux busses/tracks, each with a surround hardware I/O (one for the odd/left, one for the even/right channels), which gives PT the right information to compensate the summing.

These 2 surround auxes get their inputs from 8 (or10 or 16) mono aux channels. These 8 (10/16) auxes are the sends to your individual channels of your summing box. The odd (left) channels go to the first surroud aux and the even (right) to the second. (This „left/right“ setup is because of limmitation of surround channel output possibilities.)

For routing tracks in your session to the summing box I built 8 (10/16) busses called „to summing mixer 1-2, 3-4, ….“

The 2 surround auxes (L&R), where the complete summing hardware is inserted, are going to an stereo aux where your summarized signal can be routed to your masterbus or aux for your final digital masterbus processing.

This stereo aux is also the routing folder, so you can close the folder without thinking what’s going on inside.

The pictures show how the busses and the I/O’s are built in the I/O setup and how it is routed in the mixerwindow.
https://www.dropbox.com/s/wroma6s58h...Setup.png?dl=0
https://www.dropbox.com/s/3hufu1pn1o...setup.png?dl=0
https://www.dropbox.com/s/rbr8cjvbqx...indow.png?dl=0

The summing box inputs are connected to the interface out channel numbers which are configurated in the I/O insert setup (f.e. 17, 18, …24). On the interface input solely the stereo output of your summing box is connected to 1 pair of the configurated inserts (f.e. 23&24) . For insert I/O’s you always need the same amount of ins and outs. Do not connect the unussed interface channels (f.e. 17, 18, ….22). leave them empty. You can also easily move the interface ins and outs in the I/O insert setup where your summing box is still connected. Please keep the order of the ins and outs like this to get a logical order in your summing box.

I tested the 10 channel version with my heritage audio MCM Mk2 and it worked perfect. I can send the output of every track or bus/aux to one of the summing mixer channels („to summing mixer 1-2. ….). stereo or mono.

The cool thing is, even if you decide to NOT route all tracks of your session to the summing box, everything is still in sync because the whole summing insert is delay compensated by ProTools. :)

It’s important to know that ADC with hardware I/O insert is in some cases not 100% sample accurate (with 3rd party interfaces). But you can get it nearly sample sync if you adjust the „H/W Insert Delay“ in I/O setup. But IMO this is only a problem if you do parallel processing with hardware inserts. Not for summing.

I hope this works for you, too.

Thank you

Frank

Re: Analog Summing in PT Ultimate with working ADC - my Solution
 

Frank, great job that looks fantastic!
Thank you so much for posting this, I'll try it out soon.
herzliche Grüße, Marten

edit:
btw. I'm in Stuttgart too, don't think we've met, have we?

Re: Analog Summing in PT Ultimate with working ADC - my Solution
 

another cool thing in this setup:
if for some reasons your summing box is not connected, you can easily deactivate the 2 hardware inserts and work ITB and all stems/groups are routed correctly.

Re: Analog Summing in PT Ultimate with working ADC - my Solution
 

ok, I've finally found some time to check this out, it works flawlessly!

Even using non AVID converters, I get sample accurate sync (mind you, probably not sub-sample accurate though) using a trusty old Apogee DA-16x for DA and the Neve 8816 built-in AD on my HD Native mixing rig.

Just a heads up: you WILL loose all the inputs that correspond to the summing outputs on your interface!

In my setup, the output of the summing folder goes to an Aux track that feeds the print track. After recording the mix, I can zoom in on the print track and verify that it is perfectly in sync.

Frank, in your description, I would switch steps 3 and 4 around, this is better for first time users. Thank you so much for geeking this out!

Re: Analog Summing in PT Ultimate with working ADC - my Solution
 

Interesting thread !
I have 32 channel summing mixer, 8 mono + 12 stereo, not quite sure how to use all the surround channels to get all my summing channels, BUT I tried on your 16ch template and recording back the print track, I still get the small hardware delay (like with Reaper and so on)

Are you using an HDX system ?
Is it really possible to record back exactly on the grid with hardware and plugins ?
Thanks !

Re: Analog Summing in PT Ultimate with working ADC - my Solution
 

Amazing! Thank you Franklyn!!

I have a quantum persons 26x32, and I sum using the LittleOne 8 by Vintage Maker.

I recently started using protools but was a logic User professionally for over 15 years. I had the same issue I've dealt with for the last 3 years and everyone I asked couldn't give me a clear answer or understand what I was talking about! I actually got really good at being able to compensate for the latency in my head while mixing into my Hybrid analog chain and learning where to make edits and automation knodes even though the sound dint match the play head.

do I need another interface aside from my Quantum to try your solution? im really excited to give it a shot as its been a long time dealing with the issue. thank you so much for hard work and Charity to the community!
Best,
BabyScorpio

Re: Analog Summing in PT Ultimate with working ADC - my Solution
 

Will give this a try,

Thank you Franklyn.

Re: Analog Summing in PT Ultimate with working ADC - my Solution
 

Thanks for sharing your ideas/setup.

You should not strictly need Ultimate, Pro Tools Studio also supports surround.

It might help to understand which of the multiple latency/delay comp problems you are talking about... e.g. I'm curious if there are more than I know of.

Are you talking about third party ASIO/CoreAudio or third DigiLink or both?

1. Its certainly true that third party DigiLink interfaces can have incorrect H/W insert latency, all they can do is match the exact latency for the Avid DigiLink interface they are emulating. Not all vendors choose to do that.

2. CoreAudio and ASIO interfaces do report input and output latency information. CoreAudio at least can report different latency say for analog inputs and outputs and different correct latency for digital inputs and output but Pro Tools, like most DAWs ignores that data and uses the latency for the first I/O ports. So you'll typically get correct H/W insert ADC compensation if using pairs of analog ports, but if say on my RME interfaces I run digital AES/EBU digital hardware inserts to an outboard processor (with zero latency in the outboard box) Pro Tools will over compensate for the insert latency and move those tracks to a negative time offset. All perfectly understandable and all wrong by the expected number of samples. This is correctable in the track +/- time offset. (The whole industry really ought to be doing a better job following driver provided CoreAudio per I/O stream latency data, and Pro Tools should just have a ping function anyhow).

3. CoreAudio and ASIO? interfaces can suffer latency correction errors if "ignore errors" is enabled on an input. (These are usually much less than the very large offsets in #4 below). This is often seen in errors in just input time alignment (i.e don't need to be using H/W inserts or ADC).

4. There is a significant latency/delay comp bug (PT-293686) where if a plugin follows a hardware inserts then ADC reports large e.g. 4K size latency (i.e. a multiple of the disk playback buffer size) that latency does not actually exist and then ADC tries to compensate for it, often creating negative track offset errors. Similar things can happen with sends. The clue is the large offset that is a multiple of the disk playback buffer size)Disabling LLM and/or disabling "Allow Sends to Persist During LLM Monitoring" avoids this bug. I've reported that bug and pushed on Avid support with absolutely no result. A complete waste of my time.

5. Yes lack of ping for latency comp correction in this day and age is just embarrassingly bad. (But that's even more reason not to have other bugs, and they really need to be fixed as well as implementing ping).