thanks so much guys, I really appreciate it. Unfortunately I'l have to wait a ay or so before the next test - everything is back up and running again for a wedding edit I have to complete and a couple of 360 virtual tours I'm trialing for clients.

Would it help if I order a new TRS to XLR cable to try?

It certainly wouldn't hurt to have a spare $20 cable on hand. If a cable fails and you don't have a spare it will bring you to a standstill.

However I think it's much more likely that the problem is the mic cable.

Also, if you can come up with your other mic, that would give us one more comparison to try.

I'm always amazed people don't collect cables. From day one of my working life, I started to collect the damn things, and many are still with me. I treat them like batteries - use them till they die, then open the next one. If I need more longer ones, or really short ones, I make them, if I want something unusual, like the ¼" to XLR, to be honest if I see one on an internet site I trust - as in companies who know what they are doing, I'll order one for pure laziness. I've probably got all the bits in the workshop.

Most of my cable failures have been physical. Somebody running heavy flight case over one crushes it, or wrenching the cable out of the connector, but usually my stock going down is simply natural wastage. I've got bins full of Neutric 3,4 and 5 pin XLRs, and speakons and both versions of powercons. ¼", 3.5mm jacks and RCA phonos. ¼" to phono (RCA), ¼ to ¼, ¼ to male XLR, ¼ to female XLR.

We do video and audio, so we've also got every kind of video cable you can imagine, and so far, somewhere will be exactly what I need. I just find it strange people don't have these things, even in much more limited numbers. We buy equipment, yet we don't buy the cables?

Same here, Paul. I have old Cannon connectors with the rubber insert and the coiled spring strain relief. Yet I did not have a proper connector for an EV 666. I had to beg my brother for one from his collection. Luckily, on that particular day we were friends. ;-)

sorry for the delay gentlemen, I've been trying to finish off a wedding edit and doing some tests on 360 virtual tours (trying to diversify while everything recovers)

Test 6

https://drive.google.com/file/d/1W7CGm9LDmoPpX5SkMuT9DRWkeyidLL4o/view?usp=sharing

everything off as before, pick up the xlr cable and move it about near the dbx
mike out of the cradle and move it about
new cable
another mike (borrowed a Rode NT3)

it seems to my inexperienced ears that the mike is the problem?

Certainly some interesting results. Changing mics certainly makes a difference. Obviously that was not my first guess, with all that AC powered equipment in close proximity.

I assume the NT3 was phantom powered for this test? i.e. you did not turn off the phantom power on the dBx preamp ... just to be extra certain about what's going on here?

My only other slim thought would be to check for corroded pins on the NT1A XLR connector. It wouldn't hurt to swipe over those a few times using a Q-tip and some contact cleaner. I guess there's a slim chance you have some resistance on one pin, causing the mic circuit to become unbalanced.

yep - phantom on the NT3

I checked the pins and they look pristine, I'll give them a clean but it's certainly looking like the mike - I was with you, once I started switching off everything I realised just how much powered crap I have in the room (all useful for cameras & video editing) but scary for audio recording once I realised how complex the field is. I had nightmares expecting you to ask me to crawl under the house tracing wiring next!

I'm looking at a Neumann TLM 102.

Thanks for putting up with me and all your help.

BTW I just got hold an TVC I voiced for Tasmania Wines (don't think it's been released yet)
https://drive.google.com/file/d/1TP7PH6SFq8-NsHMyDrbP-Vx49-xsJbrE/view?usp=sharing

I had nightmares expecting you to ask me to crawl under the house tracing wiring next!
Hey, that's a great idea!

Seriously, if you're really lucky, your NT1A is registered with the factory and is still under warranty!

Once you get this straightened out, it will be interesting to see what happens as you turn things back on one by one. Given that most of the noise picked up was caused by the mic's proximity to the preamp, you might have very little trouble with most of the other stuff.

I've been following this thread because I'm going to get into Voice Over for my home video archiving project. Probably not until next winter (northern hemisphere). Been scanning lots of 35mm negatives and slides for a family history project and have some 8mm Standard and Super 8 movies without sound. So this will be a project with lots of V-O.

Anyway, ...
Checking the wiring under the floor, I like that idea too!

Speaking of the NT1-A mic warranty, Røde has a free extended warranty program that may be helpful if it's not a counterfeit. There are a lot of Chinese counterfeit mics of all types floating around and Røde has been targeted along with Shure, Sennheiser, Neuman, and I'm sure others. This is the Røde web page for signing up for the extended warranty:
https://www.rode.com/warranty/step1

The NT1-A is one of the mics eligible for the extended warranty.

One of the iises with mains power issues is that electricians following their country's rules and codes are following a process only concerned with 110/240V power, and safety - nothing about noise and interference. We get concerned about hums and buzzes, but radio enthusiasts get problems with RF noise. Those folk who still use the old short wave bands for world wide communications as a hobby often get wiped out by radio noise from the same gizmos we have issues with. We worry about 50/60Hz hums and harmonics in the audio spectrum, but the radio people have the same problems up to 30MHz or so, and our local Coastguard use 156.000MHz and that is one of the nasty harmonics of the cheap and nasty PSUs. Expensive radios have good filtering, but cheaper ones just show interference all the time. Luckily, it's better out to sea!

Mains wiring offers simple paths for this crud to spread, and just think how better it could be if wiring was enclosed in the old metal conduit, or perhaps in screened cable? It's just not designed that way, and accidental combinations of kit cause the issues we're having here. It works and is safe - that is where electricians stop. Screening often is against the rules!

the warranty sound promising but they want a date & proof of purchase - it was so long ago I'd have no idea and I'm not crawling under the house to go through 10 years of records - it's a paperweight.

Rode are awesome anyway with their warranty stuff. Don't let a little thing like the final stroke of the tenth year stop you. Give them a call and see what they think.

Andrew

I made the trip to Newcastle today and came back with a new mike

here is test 7 - everything on, everything running - the only change is a new XLR cable and a new Neumann TLM 102 mike.

https://drive.google.com/file/d/1Pm_UKUug7ceXTWdRAIxJDiF3JPImf4oK/view?usp=sharing

Well that's sorted that! Only downside being the pocket - but you'll feel confident with this new one I'm sure.
Good luck with the project.

POSTSCRIPT

sent my old mike off the Rode and it just came back:

"repaired faulty capsule & tested/serviced mic and needed to also replace DCB as it was lower gain than reference mic. Also replaced XLR connector as it was crackling"

RODE ARE AWESOME!!!!

this mic was old, there was no way I was expecting anything from them - but they came through.

Now this is something people should remember and take as positive. Says a lot about rode!

I still remember a story from ages ago about an over ten year old mic going back to Rode for a possible fix and their response was along the lines of "hmmm ... that shouldn't happen" and sending a new replacement mic back.

Rode are genuine legends and it's another reason why I only buy their stuff.

Andrew

POSTSCRIPT

sent my old mike off the Rode and it just came back:

Paul, that's great news! I'm not in the market for a mic right now, but if and when I am, I'll certainly keep Rode in mind. I'm glad this had a happy ending for you, after all the pain.