i have seen the correction tables to use with the radio shack sound
pressure meter. after setting up using 1000hz at 80db do i take
readings and factor in the corrections, for bass this means adding
progressive amounts, or do i try to get a flat response on meter down
through the bass using vandersteen sub and stereophile cd2. it seems
that using the correction numbers would greatly reduce the end bass
result. how do i proceed and get the proper results? thanks jonathan

well, i _hope_ i have been doing this right over the years (to my ears
it sounds right):

i set the sound meter to C weighting and use the Stereophile CD2...i
usually use 70 db as my test signal so that i don't get everyone around
me upset and it then allows me to see fluctuations nicely on the +/-
side. i've only really use it, however for 160 hz (or maybe 200 hz) and
lower...seems to work well for me, and again to my ears, tuning my
system with this approach worked well. surprisingly, actually, i only
adjusted the gain on my sub about 1-2 db from what i got by ear.

good luck.

On
16 Dec 2003, jljonathan wrote:

i have seen the correction tables to use with the radio shack sound
pressure meter. after setting up using 1000hz at 80db do i take
readings and factor in the corrections, for bass this means adding
progressive amounts, or do i try to get a flat response on meter down
through the bass using vandersteen sub and stereophile cd2. it seems
that using the correction numbers would greatly reduce the end bass
result. how do i proceed and get the proper results? thanks jonathan

jljonathan wrote:
i have seen the correction tables to use with the radio shack sound
pressure meter. after setting up using 1000hz at 80db do i take
readings and factor in the corrections, for bass this means adding
progressive amounts, or do i try to get a flat response on meter down
through the bass using vandersteen sub and stereophile cd2. it seems
that using the correction numbers would greatly reduce the end bass
result. how do i proceed and get the proper results? thanks jonathan

People often tend to set the bass higher than 'flat'. Put another
way: flat resposne down to 20 Hz is often perceived as 'lacking bass'
by people used to non-flat bass.

--

-S.

"They've got God on their side. All we've got is science and reason."
-- Dawn Hulsey, Talent Director

Steven Sullivan wrote:


jljonathan wrote:
i have seen the correction tables to use with the radio shack sound
pressure meter. after setting up using 1000hz at 80db do i take
readings and factor in the corrections, for bass this means adding
progressive amounts, or do i try to get a flat response on meter down
through the bass using vandersteen sub and stereophile cd2. it seems
that using the correction numbers would greatly reduce the end bass
result. how do i proceed and get the proper results? thanks jonathan

People often tend to set the bass higher than 'flat'. Put another
way: flat resposne down to 20 Hz is often perceived as 'lacking bass'
by people used to non-flat bass.

--

-S.

"They've got God on their side. All we've got is science and reason."
-- Dawn Hulsey, Talent Director

It's also useful to note that a loudspeaker that measures flat in the
near-field or in an anechoic chamber will have a downward sloping
characteristic in the far field in a real room (the smaller the room, the more
pronounced the effect. Well implemented systems in a medium sized room will
have approximately a 1-dB per octave slope over entire spectrum. In a car it's
about 3-dB.