"Lightning to USB 3 Camera Adapter" introduces audio artifacts

Got that right!


The Zoom might, although it means I usually have to toss out partially-used batteries before every show. The iPhone will often not make it. And that powered adapter helps the iPhone survive.

Great ideas. But how to power the iPhone?

I will say, I’ve been considering using a battery bank instead of an AC adapter to make the setup a little more “wireless”. The goal, though, would be to use the powered USB adapter to fork that power to the two devices.

Before we go any further… Zoom has agreed today to send me at least a new cable to try. Let’s eliminate that as being faulty. If that doesn’t fix it, I’m going to force them to replace the Zoom H6 itself. However, I’m not optimistic that that will help; my fear is that it’s a design flaw…

Via MagSafe?

Oh yea right :sweat_smile::sunglasses:. Hard keeping track here. That is good. If only the Zoom could run on MagSafe!

I did find something like this in the US store that is rated at 5V and 1A which matches the Zoom’s specs. It also appears to have a cable that would allow the compartment to close.

Lenink Power Supply Cable for AA Battery,Replace AA Battery Amazon.com

Maybe I will just get this, get a MagSafe for the phone, and get a two port battery bank and be done with it. So lame to have to take a simple, elegant setup and spend more money and a bunch more complexity to compensate for bad engineering…

UPDATE: Ugh not so fast. Why does it say 5V 1A 3W? That’s doesn’t tie out. Based on the Zoom manual, I need 5V x 1A = 5W. Some homework suggests that I need USB 3 minimum to get that power. That explains why Apple’s powered connector is USB 3. This will be hell if it’s underpowered.

Maybe I should go with this thing. It claims full 6V 1A. Cable sturdiness gets better reviews, but I’ll probably not be able to close the cover though. I resent them all for putting me through this BS! :sweat_smile: https://a.co/d/5bxDrmh

Oh - do we have specs for the current required by the Zoom?

I agree that “5V 1A 3W” is inconsistent.

It looks to me that these battery eliminator things have no active components, so I think the max current they can deliver is limited by the thickness of the cable (in eg AWG) they chose, and the power supply you use with it. So I agree your second link looks beefier, and that might be important (depending on how much current the Zoom needs).

By the way, when I click your second link, I see the “2AA” variant. Just checking: you would need the 4AA one.

Re closing the cover - perhaps you could leave it off. Or (once you are sure it works) cut a slot in the cover for the cable - the expensive battery eliminator in the first link I found earlier comes with a handy file for this purpose.

Two other ideas perhaps to try first, though:

  1. In the setup using the Apple powered USB 3 adaptor with the Zoom and iPhone… earlier in the thread, I’d noticed that USB 3 adds (optionally?) a GND_DRAIN pin among a few others, near the back of the connector - see Wikipedia’s photo. I wonder if the Apple USB 3 adaptor has those additional contacts (perhaps use the iPhone Magnifier app with the torch on to help see). If it does, I wonder if it would be possible to partially / minimally insert the USB 2 (?) plug from the Zoom, to try and avoid connecting with the USB 3 contacts, and see if that cures the clicks. Does that make sense? I have very low confidence in this idea, but I think it would be fairly easy to try, if you have things set up already.

  2. I wonder: if you plug the Zoom (bus powered) into a Mac and make a recording - does it have clicks? It might be easier to prove to their support that the Zoom is faulty if so.

Are we having fun yet?? :slight_smile:

I may be exceeding the extent to which I want to re-create Frankenstein’s monster LOL. I’m already nervous about rigging a custom power supply for the Zoom and not being sure if it delivers the right power specs, but I did order one and I’m gonna try it out when it arrives.

The up side is that I have a beefy power bank, and I can secure it to the mic stand with an iPhone mount I have. It’s pretty much a perfect bracket for the job. I’ll show the photo later if this thing works out :slight_smile:

Dadgummit, if I had noticed your comment, I wouldn’t have bought the wrong one! Fortunately, they refunded me and let me keep it anyway.

Okay, so! I got the right one of these today and hooked it up and it seems to work fine so far, including phantom-powering my external mic (there was some concern about whether the amperage draw would be sufficient). I’m going to have to carve a groove in the plastic battery case cover to allow that USB wire to hang out the back, but that should be do-able.

So I hooked everything up with an arrangement that avoids power-over-USB completely as well as “batteries”. Notably, the powered “USB 3” adapter is out. And now, the Zoom is powered by this bizarre “battery eliminator” product, and the iPhone is powered by MagSafe, and both those USB power sources are plugged into a hefty power bank attached to the mic stand with an iPhone mounting bracket. And there are enough ports in the power bank to also power my USB-powered “fill light” for video recording.

The resulting audio is pristine (the playing, not so much):

Dropbox - all_external_power.m4a - Simplify your life

Conclusion: this is a workaround that can enable live video without running out of power, and without introducing audio “clicks”. The down side is that I had to purchase the “battery eliminator” and the MagSafe and deal with the attending mounting complexities in order to compensate for the fact that the Apple+Zoom technical bug has not been resolved by either of them.

If time and energy permit, I will keep pursuing the issues with Zoom and Apple. Otherwise, I’ll stick with this workaround.

Thanks for the suggestions, guys!


(Sorry, I forgot to reply earlier.)

Excellent! Thanks for reporting back. Looks good.

Sadly, the audio doesn’t seem to play for me? (In Chrome on an older Mac, and on my iOS 16 iPhone.)

But I’m very pleased / relieved that it actually works (if I’m not speaking too soon?) :tada:

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Yea I certainly like not having to worry about batteries.

Yes it didn’t play for me either. All I did was paste the Dropbox link and it rendered a player that just won’t play. So just now I “quoted” the URL and it rendered it differently and it opens and plays. Please try it.

@ace I have had this problem here with links before. Is it a bug?

Oooh lovely guitar sounds! And I hear no clicks :slight_smile:

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Thanks. Yea, I wish I knew the engineering behind why there are clicks with the one setup. But alas, I have a working alternative :-)

I have a string of wild guesses if you are interested :slight_smile: (And I’ll write them here even if you’re not!)

This Zoom model sometimes needs a little more current than is strictly allowed by the USB spec. Apple’s older adaptor is lenient about that, because this was common when the Zoom device and that Apple adaptor were designed (at similar points in time, when USB 2 was the public standard). Apple’s newer adaptor is designed to supply more (much more, on request), but is more stringent about it (=conforms more closely to the spec) - it’ll only supply more when the device negotiates it, and the Zoom doesn’t do this. If the Zoom can’t draw enough current at any point, some part of the signal chain within (could be analog or digital) drops out briefly, introducing a click in the audio.

Perhaps. All just speculation.

I love this theory, and I think someone mentioned it above! :smile: The problem is, if you look at Case #1 of my OP, the canonical problem manifestation occurs when there is no power even connected to the problematic USB 3 adapter, and the Zoom is therefore powered completely by internal AA batteries. This is also governed by the setting I was using whenever I used the Zoom as a USB interface:

Experiments above confirmed that the only option that even accepted bus-power was the first one, which makes sense. The others simply would not power up when the batteries were removed.

And at the other end, the iPhone was running on its own battery as well. So there shouldn’t have been any power negotiation going on or any power traversing the circuit at all. Should have been pure data.

One could wonder if the Zoom was still negotiating power poorly here; but given the setting shown above, we are telling Zoom to not even bother trying. The USB 3 adapter, on the other hand, must determine whether to negotiate power based on, for starters, the presence of a connected power supply at the designated lightning port. Since I have nothing connected there, that handshake should never attempt. And even when I do connect a power supply, this test showed that audio was still clicky.

Maybe it has nothing to do with the power. Maybe the Zoom doesn’t know how to send data over USB 3 reliably? Maybe its audio buffers underrun, causing clicks. That would explain why the Chinese USB 3 adapter didn’t help. And maybe the Presonus talks USB 3 fine, so it sent clean audio while being bus-powered from these USB 3 adapters. The problem, of course, is that only USB 3 adapters offer the power-delivery feature. Unless I just haven’t looked hard enough??

It took forever, but this replacement cable did finally arrive. For the sake of completeness, I hooked it up and it didn’t help:

Mic > Zoom > new USB Mini cable > Apple USB 3 adapter > iPhone capturing video

Both devices running on battery power; no power connected to the adapter. Still clicks. So the remote possibility of the cable being an issue has been eliminated.

Zoom has finally agreed to replace the recorder. I sent them the necessary info and am waiting for an RMA. Given that the new one will probably have the same issue, I wonder what their engineering team will then say…