From the Desk of Art Noxon

Art Noxon is a fully accredited Acoustical Engineer with Master of Science degrees in Mechanical Engineering/Acoustics and Physics. A Professional Engineer since 1982, he is licensed in Oregon to practice engineering in the public domain with the specialty area of acoustics. A prolific inventor, he developed and patented the iconic TubeTrap, the original corner-loaded bass trap/treble diffuser, 150 other acoustic devices, and counting. Lecturer, writer, and teacher of acoustics, he has presented 7 AES papers, numerous magazine articles, white papers and blogs. He is president of Acoustic Sciences Corporation, the company he founded in 1984.


Church Carpet Not Good For Organist

Question

I’m the organist at a church with a beautiful pipe organ in a historic stone church. I’m sure it sounded great in the old days they covered the floor with beautiful carpet years ago and lost the sanctuary lost its reverb. They won’t remove the carpet to get the reverb back….Do you know of any clear paint I can use to remove the carpet’s acoustics so I can get the reverb back into the sanctuary? 

Answer

Carpets do absorb a lot of reverberation. Old school organ music is supposed to be played in highly reverberant rooms, where each note adds to the reverberant sound of the preceding note, creating chords without having to play all the notes at one time...... Modern organ music is written for electronic organs in modern, non reverberant spaces. You can hold all the keys down and not run out of “air” and no longer need the reverberation of the room to create chords.

One thing people do is to mic the organ and run signal thru reverb circuit and play the reverb through a bunch of speakers scattered throughout the sanctuary, so the sanctuary sounds like it is reverberant. 

Another version of this is to play the organ in a reverberant space, artificially reverberant or physically reverberant and then let the composite signal the direct + reverb signal play out into the high sound absorbing sanctuary. Not the same as having a reverberant sanctuary but still a lot better than no reverberation. Sort of like having a old wood choir room in the balcony, which releases some blend of direct + reverb into the sanctuary at one time. 

I don't know of a carpet paint that improves the sound reflection of a carpet. Are you sure it is the carpet? Have there been any other changes in the building? Any remodeling work? Stain windows pulled out, replaced by Anderson windows? Why is the reverb of the sanctuary a problem now and it wasn't a problem 10 years ago? 

I took the web site photo tour of the sanctuary.....

I see: Red carpet downstairs, green pattern carpet upstairs and red cushions on all the wood seats. I think I see some sort of runner on aisles. There is a lot of sound absorption in this sanctuary already. 

Which carpet is untouchable? The red downstairs or the green pattern one upstairs? 

I'll bet it's the red one downstairs. Can you get them to remove all the cushions and carpet out of the balconies? That way you'd have a reverberant top half to the sanctuary and an acoustic dead lower half. 

Good luck and keep me posted…
—Art Noxon