Presonus NSB latency - follow up to a previous follow up video
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- čas přidán 10. 09. 2024
- This is another (and possibly the last) follow up video to a previous follow up video covering a potential latency issue with our Presonus NSB 32.16 along with a Presonus 32SC console.
Original follow up video:
• Follow up to the Preso...
The original issue at the event was a drop in audio... not latency (as I previously stated). I go over the changes we made to the setup and reference what the root cause was of the drop in audio.
Wow man!!!! This is huge job!!! Make sure Presonus folks have access to this!!! It will help many people!!! Thank you!!!
What an interesting problem. Sounds like a ground potential difference Between front of house and stage. Or a high static environment day. Don't think the sampler was mismatched that would've been very obvious and I don't know how it would've worked, if it was mismatched it would be very garbled!
I've had a few occasions with sample rate mismatches with USB interfaces and a certain piece of software dragon dictate Mac where it likes to change the sample rate on me whenever a USB audio device was plugged in.
While I am not doubting your "shielding theory" I am finding that just the Ethercon connection is mostly the issue with audio dropouts. I tried different setups and found if I use a cable that doesn't have the ethercon connector, I will have no dropouts. Making small adjustments to the ethercon ends has helped a bunch, and after finding a cable that will work, the dropouts have stopped. The new firmware may have helped with this too, I am not certain. I do know that there are some cables that just don't work well (even tho they are on the "list"). Thanks for the info!
Thanks for your comment. Good points. The issue isn't so much with the Ethercon, but more of a grounding/shield issue. Without an Ethercon connection, a shielded network cable will be grounded at the RJ-45 shell connector (metal connector); this can be tested with an ohm meter on the RJ-45 shell at each end. Unshielded network cables usually have plastic RJ-45 shell connectors; these are basically UTP cables.
Yes, I was hoping a firmware upgrade would have addressed this issue... but no luck! It would be nice if Presonus would update their cabling documentation...
The basic issue is with creating a ground loop on a conductor of your data cable that disrupted communication. Other protocols like AES50 are also sensitive to this.
except AES50 attempts to solve this by bonding both chassis together with the cable shield, and it's usually UTP applications that experience static discharge related issues (or even damage)
Yes, AES50 can experience the same issue.
👍✅ Always learn something from your videos, tks!
Thank you!
@@stageleftaudio 👍✅ nope, thank YOU
👍✅ One question that I didn't see in the video, are you running all you AC from the same Furmans, FOH and all stage equipment? I'm guessing yes and its strange you should get a problem like this using the same source/ground/neutral although musicians sometimes bring the ground lift problems with their equipment.
Good question. In this video, all AC is running from the same Furman (voltage regulator). At the event location (where this issue first occurred), FOH and stage were together on one circuit, with the FOH console being the only device on regulated power. Though, the NSB was not on regulated power, but was using one of the rack mounted Furman PDU devices.
@@stageleftaudio 👍✅ Tks for the answer. Years ago i saw this idea somewhere and ever since insist that all energy is on the same circuit even if it means running 50 meters of cable out one way and 30 meters the other way to a remote speaker when a socket on another circuit is there already. Extra work and equipment to avoid a possible but unlikely problem but to me that is the professional way to do it and the professional customers do notice and appreciate it as you well know.
Great work. You think I'd see the same interaction between the 32R and 32SX consoles using CAT5E? Scary stuff
Possibly... It probably all depends on what cable you are using (shielded, non-shielded). When the audio dropout occurred at the event (Dec. 2023), we were using Cat5E Ethercon (Shielded). Aside from that one audio dropout at the event, there were no other issues with connectivity between the console and the NSB during the show.
um... I disagree with this completely. In my opinion it would be best to make sure it's shielded, ground is connected *TO THE SHELLS* of the neutrik ethercon connector (use ohm meter to check shell ground continuity) . i'd also run a power cable along with the data cable for FOH *from* the stage box so there is no ground potential difference from using separate power sources. I also believe the voltage regulator is a waste of money since most gear uses switching power supplies that can support voltage sags. In addition, presonus sports the AVB/TSN, IEEE ethernet standard and I'd be curious if buffering the signal with a AVB compatible switch/hub could also have helped, especially on runs longer than 200-feet
Thanks for the comment. Yes, the shielded cable was grounded at the shells on both ends (confirmed by my ohm meter)... prior to removing the ground on one end. The original ethercon cable used at the event (where this issue occurred) was grounded at the shells as well (150ft ethercon). At the event (as well as in the setup for this video), all power originated from the same circuit. All our Ethercon cables are 150ft. I agree, a buffering device would have probably helped, but it would need to support about 2 seconds.
Yep, I agree, the problem was a ground loop created by the Stage and FOH sourcing different power outlet sources with different lengths to the breaker box. Best to run power from single area of the building but that is not always possible. I'm surprised other pieces of your gear did not act up as well or have ground loop hums, etc.
Thanks for your masterclass. After know the drop sound issue, do you recommend CAT5 than a CAT6 shielded?
Thanks for your comment. Presonus states the use of Cat-5e or Cat-6a cabling. The Cat-6a cabling is backward compatible with Cat-5e. The Presonus documentation appears to be a little behind with updates on what cables to use. According to Presonus, Cat-5e may be ok (it's rated at 1Gb/sec) up to about 300ft. (90m). The Ethercon cables you seen in the video are all Cat-6a (10Gb/sec). You could always try a shielded cable first (cat-5e or cat-6a) and if there are audio drops, try removing the shield from one side (one side only) of the cable.
If Presonus is watching they need to update their manual or add a ground lift 😅
I agree, their documentation does need to be updated! In my personal view, ever since Fender purchased Presonus (a few years back), seems like much of their documentation (perhaps not all) was placed on the "back burner".
Thanks for your reply, Bob. I use Qu-24 with AR2412 Digital Rack from A&H and I have Mercator 6A UTP cable with Hicon connectors to link both items. It works fine to me. Highly recommended.
Finally, do you have a video using the dbx DriveRack PA1-2? I want to get this gear but I am not sure about quality and useful during live events.
Thanks for the suggestions on the cable! The QU consoles are great!
We do not have any videos covering the dbx driverack gear. We use the dbx 260 series anytime we need to control crossover points. The dbx 260 (older series from dbx) has done very well at events. We use the 260 for crossover only, and for the occasional cardioid sub setup. I think the driverack units PA1, PA2, 260 are all good. They work great when we run an all analog sound system setup. Unfortunately with digital snakes, most setups don't allow for crossovers at FOH. Any crossover would need to be at the stage and with someone to set crossover points based on what you tell them. We do use the 260 with our digital consoles, but when using analog snakes and when using passive subs (with powered tops). For us, the dbx driverack units are an integral part of most all of our sound system setups.
@presonus @thesoundcouple