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~misfit~[_3_] ~misfit~[_3_] is offline
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Default Attenuate highest highs?

On 20/02/2020 10:44 am, Trevor Wilson wrote:
On 19/02/2020 1:02 pm, ~misfit~ wrote:
On 19/02/2020 11:14 am, Trevor Wilson wrote:
On 19/02/2020 6:41 am, Trevor Wilson wrote:


**Those "tinkling noises" you hear are somewhere around 3kHz.

**Should read: "....somewhere around 3 ~ 5kHz."


It seems to be higher.


**Until it has been measured, then we're both guessing. Few instruments go as high as 5kHz. There
is almost nothing beyond 10kHz in any music.


FWIW I just did this on-line frequency hearing test:
http://onlinetonegenerator.com/hearingtest.html
and through my monitor-mounted Dell soundbar (with 25mm drivers) I could hear to just over
12.5kHz but through the stereo in question could only hear to about 11.5kHz. That's quite a bit
lower than the last time I used a similar tool a few years back. Maybe those years when I spent
hours several nights a week at a mixing desk at live (loud) gigs in my 20s are coming back to
bite me?

So now I'm a bit baffled. The issue I have is due to sounds at the highest frequencies that I can
hear and that seems to be ~11kHz with this system in the current configuration. Maybe they have a
peak about there or are flatter than the other speakers I've tried...


**Until you perform some measurements, you're guessing. You could try to acquire a (preferably
digital) parametric equaliser and perform some measurements.

I still betcha room treatments will solve your problems. IME (which is substantial), room
treatments solve most mid-HF problems, PROVIDED there is nothing inherently wrong with the
equipment, or the amp is not being clipped.


Very few instruments possess fundamentals that reach 5kHz. A very tiny number posses harmonics
of significant levels that exceed 10kHz.

Turn the volume down and see if the sound is still annoying. I suspect you are clipping your
amplifier. Clipping can generate large amounts of high frequency harmonic content. And, just to
shut down any myths you may have heard: Valve amplifiers WILL clip and WILL generate excessive
high frequency harmonics if over-driven.


It's not clipping. The Dynaco ST120 I have hooked up at the moment is a solid-state amp and I no
longer own any valve amps.


**You've checked with a 'scope to ensure no clipping then? Or are you guessing again? It might
worth looking at the waveform on a 'scope to see if there are no parasitics present.


Of course I'm guessing. I know this is rec.audio.high-end but I don't have (or have access to) a
parametric equaliser or an o'scope. When I say I'm not listening at low 'office level' volumes I
also don't mean ear-bleeding party volumes. Maybe somewhere in the 'half volume' range on a 60 - 80
wpc amp... I've currently got a Marantz Stereo Reciever SR4023 hooked up set to 'flat' (it has a
pre/power loop for the subwoofer amp) and the issue is the same - but the amp belongs elsewhere.

However I have used these speakers with a few different amplifiers, (from 25 watts /channel class A
up to 160 w/c RMS) and at different volumes and in different locations and the issue I perceive
persists.

I realise that without measuring we're all making educated guesses. Really I just wanted to know
what to add to the speaker crossovers / tweeter wires to attenuate frequencies above say 10kHz by
maybe 3db (and not attenuate the crucial frequencies where female vocals and the upper reaches of
electric guitar solos and harmonics reside).
--
Shaun.

"Humans will have advanced a long, long way when religious belief has a cozy little classification
in the DSM"
David Melville

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