On a couple of occasions I used the reverberant acoustic chamber research facility at the NRC in Ottawa. I was testing the noise reduction of a new audiometric test booth I had developed at Tracoustics in Austin, TX but built by Eckel Acoustics in Canada. After a full day of setting up the test chamber, including catching up with missing parts, we came back the next day ready to test. All of the speakers and microphones were set up, I went into the control room and found that there was no signal going to the chamber. No sound at all.
Trouble shooting began as did lamenting about it being the end of the fiscal year with no money left for repairs. After two hours, we discovered that an earlier users of the chamber had used their own amplifiers. The primary amps had been returned to their bays, but not reconnected
The sound of pink noise had never sounded so sweet after we were finally able to get measurements underway.
On a couple of occasions I used the reverberant acoustic chamber research facility at the NRC in Ottawa. I was testing the noise reduction of a new audiometric test booth I had developed at Tracoustics in Austin, TX but built by Eckel Acoustics in Canada. After a full day of setting up the test chamber, including catching up with missing parts, we came back the next day ready to test. All of the speakers and microphones were set up, I went into the control room and found that there was no signal going to the chamber. No sound at all.
Trouble shooting began as did lamenting about it being the end of the fiscal year with no money left for repairs. After two hours, we discovered that an earlier users of the chamber had used their own amplifiers. The primary amps had been returned to their bays, but not reconnected
The sound of pink noise had never sounded so sweet after we were finally able to get measurements underway.
I understand! As we like to say, "the problem is always the last place you look." :)
Unless you're chasing a ground loop.