Child of #692 (Cloud Seven audio master). Venue: cloud-seven.
Problem
The audio in the bar crackles. The dining room plays the SAME source cleanly, so the fault is not in the source (Sonos Port) or the shared upstream: it is isolated to the bar-specific part of the chain, after the source split.
Where it can be (bar chain only)
Tesira output feeding the bar zone -> the bar channel on one of the two ReVAMP amps (2600 / 2150, Server Room 201) -> speaker cabling -> the bar speakers. A crackle that survives a clean dining feed points at: a loose/oxidised speaker connection or damaged speaker cable on the bar run, a failing amp channel, or a bad output on the Tesira card feeding the bar.
How to narrow it
- In the Tesira (once #682 access lands): watch the bar output meter with the bar muted at the speaker end; a clean electrical signal that still crackles acoustically = downstream (amp/cable/speaker).
- Swap the bar and a known-good zone at the amp inputs (or reassign the bar to the other ReVAMP channel) to tell "amp channel" from "everything after it".
- Physical: reseat and inspect the bar speaker terminals and cable run.
Mostly hands-on in the rack / at the bar speakers; the Tesira-side metering is remote once Turbo/TTP is up (#682). Not the same problem as the bar gain miscalibration (that is a level/taper config item, tracked under #682).
NEXT STEP (single, do this first)
A controlled level test, driven remotely, one person listening in the bar. We now control the Bar Sonos remotely, so we can reproduce the crackle on demand instead of waiting for it. One person stands in the bar; we play a steady track to the Bar source and step the volume 10 -> 30 -> 50 -> 70 -> 90 -> 100, holding a few seconds each. The listener notes at which level the crackle starts and whether it tracks loudness. Takes ~5 minutes, needs a quiet bar (see timing). Book a slot and we run it live.
The result tells us where to go next, before anyone opens the rack:
- crackle at ALL levels, even low -> bad connection / cable / failing amp channel (electrical). On-site: reseat the bar speaker terminals, then move the bar feed to the other ReVAMP channel to tell "amp" from "everything after it".
- crackle only from ~80-100, clean below -> amplifier clipping or an under-driven/failing channel, or a speaker at its limit. Often a gain-structure issue, which overlaps the separate bar volume-calibration item (#682).
- crackle random, unrelated to level -> loose/intermittent connection, thermal, or interference; hardest, needs the on-site isolation swap.
TIMING INSIGHT
- When it crackles is the biggest clue and it is free to capture: ask the bar staff to note whether it is constant, only when loud, or comes and goes. That one observation halves the search space (see the branches above). Record answers here.
- Reproduction must happen in a quiet window (bar closed / no guests): the test needs real level, up to 100, which is disruptive and also lets the listener actually hear the crackle. Do NOT run it during service.
- Deadline pressure: the September events are the hard date (parent #692 / venue tracker #578). The level test is remote and 5 minutes; the physical isolation (rack/speaker work) needs an on-site person and should be booked into a pre-event quiet slot, not left to the event day.
- Intermittent risk: if staff report it comes and goes, a single test may not catch it. Then the fallback is to leave a steady tone on the bar at a fixed level during a quiet hour and have someone note timestamps when it crackles, to see if it correlates with anything (AC kicking in, the room warming, other gear switching on).
Resolution plan + timeline (agreed 2026-09-11)
Owner: Tom sources the technician and provides the quote.
- Tom finds a person to investigate the physical setup and provides a quote for the visit.
- Technician visits on site (within 2 weeks, i.e. by ~2026-09-25, possibly already the week of 2026-09-15). On the visit they read the Tesira programming and determine which of three it is: (a) a configuration problem, (b) a broken amplifier, or (c) broken speakers.
- If configuration: fixed on the spot during that first visit. Done.
- If hardware is actively broken (amp or speakers): parts are expected in stock and fast to deliver, but a second visit is needed to install them. Add ~2 weeks for that.
Timeline: minimum 1 week, maximum 4 weeks. Everything resolved by ~2026-10-09 worst case.
Cross-link: this technician visit is also the moment the Tesira programming gets opened on site, so it doubles as the in-person resolution of the #682 access question (whether the design is Secure Inside password-locked). Whoever comes should be briefed to also (a) note if a design password blocks them, and (b) enable TTP in the design so we can control and monitor the system remotely afterward. See #682.
For the venue team (plain language)
The bar sound crackles. We have a plan and a timeline.
- Tom is arranging a technician to come and look at the bar's speakers and amplifier, and will send a quote.
- The technician can come within two weeks, maybe already next week.
- On that visit they find out whether it is just a settings problem or something physically broken.
- If it is settings, they fix it the same day.
- If a speaker or the amplifier is broken, the replacement parts should be available quickly, but a second short visit is needed to fit them, which adds about two more weeks.
- So: best case about one week, worst case about four weeks (fully sorted by early October).
While they are on site they will also open the Biamp settings, which lets us tidy up the other bar audio items (the wrong panel label and the bar being too quiet until near maximum) in the same trip.
Parallel track (not this ticket): separate from the technician visit, we are standing up a permanent Windows Tesira gateway on the venue LAN for ongoing remote Tesira access, tracked as #696 under #682.