Jim Lesurf wrote:
In article , Wally
wrote:

Jim Lesurf wrote:




[snip] to the crescendo


To my mind, the system as it stands is the baseline - for the
foreseeable future, I'm essentially committed to a tri-amped set up, and
the idea is to try and make it better without spending a fortune. While
I was initially less than conducive to using measurements, I would say
that I'm more willing to sing from that particular hymn sheet after
seeing driver free air resonance graphically displayed on the scope, and
having heard the improvement to the bass that came about from using the
SPL meter (compared to my MkI lug-'ole attempts). With this in mind,
I'll be taking a set of measurements of the overall frequency response,
such that the effect of subsequent changes can be analysed objectively.


One of the things I would recommend people do is to make some 'baseline'
measurements of the in-room response before they start any changes. [1]
This helps to assess any perceived effects and decide what may be the real
reasons for improvements. This in turn aids making decisions, allows the
user to focus on what is worthwhile, and to avoid waste of time or cash!
:-)

[1] In this context it does not matter much if the sound meter is a
cheap/poor one, or if the room has an odd acoustic. The aim is to do a
'before/after' comparison and have the info as a reference.

Slainte,

Jim


Jim - or anyone. I did try this and got quite bizarre results - huge*
dips at certain frequencies I would not have expected, in fact the only
flat region was between 2kHz and 4 Kkz. That was using various frequency
steps (60) between 100Hz and 6KHz. For a quicker cruel test - say 10
steps - what would you regard as the key frequencies at which levels
should be equal?

Thanks

Rob

* well, the peak signal was 60dB (flat 1.7-3.9kHz) at the listening
place; min 20dB at 500Hz, 100Hz; and 35dB 5.4kHz and 4.5kHz