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

On 20/02/2020 10:57 am, Trevor Wilson wrote:
On 19/02/2020 12:28 pm, ~misfit~ wrote:
On 19/02/2020 8:41 am, Trevor Wilson wrote:
On 18/02/2020 3:28 pm, ~misfit~ wrote:
On 15/02/2020 7:32 am, Peter Wieck wrote:
I think you are missing the point. If too much energy is being dissipated by the speakers in
the high range, then too much energy is being dissipated in the high range. And, the brute
fact of the matter is that there is not a whole lot going on above 15 kHz anyway. So if the OP
perceives that his speakers are overly bright, we should start there.

A lot of the material I listen to is 'full range' and does have a reasonable amount of high
frequency content.

(I was listening to the Lindsey Buckingham Christine McVie album the other day and there were
'tinkling' noises in one track that I could hear but not clearly. It made me wonder why two 70
y/o plus musicians were using sounds that they likely couldn't hear!)

**Those "tinkling noises" you hear are somewhere around 3kHz. You need to employ some room
treatments to deal with the problem.


They sure don't seem to be and I don't have an analyser.


**They will, almost certainly, be below 5kHz.


I might have to look for a phone ap. That said my low-end Samsung phone is very low on storage
space, I've had to delete apps recently...

I agree that attenuating the high range is not the answer. But neither is tweaking room
acoustics. We need to work with the Human Ear and how we perceive sound at various volumes.

Which is why balancing the speaker output does seem to be an answer, especially given that one
does not normally blast music in an office. At low volumes, in general, not enough energy gets
to the bass driver(s) to balance the treble, especially as speaker efficiency drops. These are
88 dB speakers, not horrible, but not great either.

I do generally listen to music with a wide dynamic range so the volume is set higher than it
would be if I were listening to compressed pop or rock music. I sometimes listen to music while
computer gaming and it can be louder than you'd expect in an 'office'.

**Is the amplifier being allowed to enter Voltage limiting (aka: Clipping)? If so, then all bets
are off. You may need an amplifier with more output Voltage capability.


It's not clipping.


**How do you know?


I don't KNOW per se but I've used different amps and I don't listen at volumes above about 50%.

Â*I've tried different power amps and the problem is
with the speakers.


**Again: How do you know? How do you know that the room is not the problem?


As I mentioned elsewhere I've tried these speakers in different rooms including my very 'soft'
bedroom and the problem follows them.

I use the term 'office' loosely to mean the area of the house where my computer and desk are.
It's a habit I picked up when I owned a small business and did my stocktaking and accounts etc.
from a home office.

Eschew needless complexity. If the electronics have a "Loudness" function, start there. If
they have tone-controls try *BOOSTING* the bass - again that nasty issue of low-volume weak
bass is more at-issue than excess treble (at low volume). Failing both these things, is it
possible to relocate the speakers, moving them more towards room corners, or closer to the
floor, or similar so as to help 'boost' the bass response. However, this might sacrifice
sound-stage.

The bass is good. I'm using a small kitset pre-amp with no tone controls which goes through a
crossover in a second-hand kitset subwoofer amplifier. (Playmaster 300W Subwoofer Amplifier.)
The crossover takes away all of signal below a certain point, sums it and feeds it to the 300W
MOSFET amp. It has three selectable crossover points and a level control.

**You're an Aussie then?


I live in South Auckland.


**Ah. We Aussies always forget about our Eastern state. :-)


Heh!

I've got it set to the lowest of the crossover points (which are 70, 90 and 120Hz) as I want to
preserve as much directional information from low frequencies as possible. The Sony SS-K30EDs
seem to handle frequencies down to 70Hz just fine with minimal drop-off.

The subwoofer is a very inefficient thing that I built braced 25mm MDF a couple of decades ago.
It's a 10" driver in a ~40l internally-braced sealed box and as such is very 'musical' when
compared to ported subwoofers that I've heard. It's response tails off below about 26Hz but I'm
fine with that.

Only after the obvious fixes have failed should we push towards more heroic measures.


**Room damping treatments and ensuring your amp is not clipping should go a long way to solving
your problems. Give me a call. I'm in the book.


Thanks for the input Trevor. I live in rental accommodation and am 'under the sword' - the
property could be sold to developers at any time and I'll need to find somewhere else to live.
(It's been that way since the landlord warned me a year ago and there's a housing shortage here.)
So I'm not that keen on spending too much effort on room treatments. More pressing is selling the
surplus-to-requirements speakers and old Thinkpads etc. that are filling the back bedroom!


**Room treatments can be VERY, VERY cheap and easy to apply (temporarily). Old rugs, mattresses,
etc work just fine. In fact, back in the 1990s, I took part in a couple of hi fi shows in Las
Vegas. At one show, some other Aussies (Krix Loudspeakers) had their room near to mine. Their room
possessed extremely poor acoustics and the guys set about to rectify the situation as quickly and
inexpensively as possible. They used some old cardboard boxes, duct tape, a Doona„¢ cover and some
Dacron„¢. They constructed a false 'wall' from the cardboard and duct tape, measuring around 3.5
Metres X 2.5 Metres X 400mm. They filled it with the Dacron„¢ and covered the whole thing with the
Doona„¢ cover (for appropriate cosmetic effect). Problem solved at the cost of some Dacron„¢ and a
roll of duct tape.

I would encourage you to try room treatments, before you spend too much time, money and effort on
other things.


Cheers. I fondly remember the 'listening room' in a flat I was in a few decades back. All of the
walls above chair-height were covered in op-shop blankets / duvets then covered in egg trays
(mainly to disguise the mismatched blankets). We also had double-layer egg trays on the ceiling.

My flatmate had a good turntable, (as well as tone arm, cart and stylus) that was made from a solid
block of marble, all really expensive by our standards. I forget the make or model. As long as the
source is good I've always been about the speakers and to a lesser extent amplification. Then (and
especially these days) I believe the biggest gains in a system can usually be made with the choice,
design and placement of speakers.

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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