Speaker stuff
Placement
Sitting to far from your speakers means listening to room reflections. Do want to hear the music :
sit closer to nyour speakers.
Global recommandation :
Distance between speaker 2-3 meter. Distance to listening position 2.5-4 m depending
on room size and personel taste. But DO remember : if you like it, it is fine.
Tweeter crossover-filter.
This is a very useful tip, especially for metal and ceramic domes. And again it is
(almost) free.
Put a resistor of 20-50 ohms parallel to the tweeter. It damps unwanted oscillations
and give a smoother sound. The ca. 0.5 dB lower output sensitivity isn't a problem (for
me).
Most tweeters have a resonance frequency between 800-1500 Hz. Due to the
crossover filter they do not receive much signal close to this frequency , but the filter
also prevents damping of unwanted resonance, the amplifier can't use it's "damping factor" .
If any resonance is occurring, the
amplifier can not damp it. The amp can't "see" this unwanted output, the series
capacitor in the filter prevents it. Oscillation will occur : Just slap something and it will
oscillate at its own resonance frequency. The proposed resistor damps the small
amount of energy of the oscillation. I use an 47ohm metal film of 1Watt and it works
fine with my Tannoy J30's and Kef reference 104's ( 39 ohm). If you have an 4 ohm tweeter a lower value R is
recommended (~22 ohm). The acquired power value is dependent of total frequency
range and maximum power. Just try , if it becomes warm it is too small.
N.B. If you use L-pads you have already a parallel resistor
A story : Why audio manufactures suck, part 2 (real life example)
In Audio & Techniek was a story about this modification. A speaker from brand X was
modified with the parallel-tweeter-resistor and the sound quality was considered as
much improved.
A&T: Please consider this modification
brand X respomds : (after experiments) : The tweeter output is 0.4dB down.
A&T : Have you actual listened to it?
brand X : Ehhhh... No, You know : what you measure you know : so we
don't like it. (Dutch : meten is weten)
A&T : Please Do Listen To The Speaker!!
brand X : Ehhhhh... oke, (not enthusiastic)
later : X : Wowh .... this is nice. We will perform this modification, and call it
"PRO" Thank you A&T !
Need I to say more ! : (some) manufacturers are very reluctant to listen (just my humble opinion).
Compare it with building cars without serious test driving. Cooking without tasting, seems to be ok for McDonald's
but not for a decent restaurant.
another hot tip :
velt ring
Do you remember the Rogers LS3/5 's ? After removing the grills you see a square of
velt arond the tweeter. I tried it myself with my tannoy's an I liked it. Sligtly better
placement an a more intimate sound. I gues the ring prevents some reflections of the
treble. I used a piece of the same diameter as the tweeter (2.5cm). Experimenting is the way to go.
A good thing of this tweak is : it is almost free!
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