The importance of room size

Hi Folks, thought that it was time to do another post on putting together a music system. We have already covered a few points such as moving your speakers out from the rear wall, giving them a chance to “breathe”.  As you already know,  moving speakers out from the wall both behind the speaker and from side walls usually makes a huge difference in the sound. The sound can be more open or closed, greater depth of field can be achieved and imaging can be greatly enhanced. One very important factor that we have yet to talk about is the available cubic footage that is available and how this can impact on your system.

Those of you “audio people” who have been listening to music may well remember the impact of many “british” hi-fi speakers when they truly hit our shores in the 1970’s. Many of them were quite small and actually many new smaller models were introduced. These speakers were capable of incredible performance in dealer showrooms but often when you purchased the speakers and tried them out at home, the sound could be “way off” from what you experienced in the store’s “demonstration area”. There are many possible reasons for this including electronics, source, speaker wire etc. but more often that not, the primary reason was one or all of;

  1. Room size – dealer soundrooms were usually somewhere around 10’x15′ with 8 foot ceilings, usually less than an average living room or rec room but more often than not, larger than room sizes in the U.K.
  2. Break-in period. As you all know speakers as most audio components including cables) sound much different after they have many hours of play on them (usually 150-400 hours of play)
  3. Speaker efficiency. Most of these speakers operated at a very low level of efficiency which was measured by placing a microphone 1 metre from the speaker and feeding 1 watt of noise into the speaker. The measurement was done in decibels or dB and more often than not the speakers were in the 85-88 dB range. (each 3 dB increase was roughly equivalent to doubling the power on your amplifier)

The larger the room, the more space there is to fill – obviously. To give an example how room size impacts, prior to setting up my store, I auditioned pretty much all of the equipment in my store using my own speakers at home. my room at home is about 12′ x 27′ with 12′ ceilings so a large room. In some cases some amplifiers simply didn’t “fill the bill” – including small tube units. I suspect that the problem was the amplifiers could not provide enough power to drive my floor standing speakers. In other respects, the amps had plenty of power but sound was lacking (obviously theses were sent back). When I opened my store, the sound area and is very small (approx 9’x13′ with 7.5-8′ ceiling). The advantage of this room size is that bookshelf speakers work great while large speakers can actually sound boomy, it almost seems the walls begin to vibrate and “trap” sound. Yes, I know there are architectual cures available but we take the stance that treating the room is rather like cheating, as most of you out there will not spend hundreds of dollars to make the room sound great. You simply need to purchase a smaller speaker and of course the advantage here is you can get fabulous sound with a low powered (50wpc or under) amplifier.

As mentioned previously in an earlier post, whatever the speaker you purchase, make sure it fits the room and works with your existing equipment. The sit back and enjoy the great sound.

gord@allthatjazzhifi.com