Xonar DX RMAA

My new measurement card.

SGD$128 for this kind of performance. Some manufacturers should be ashamed.

The D2X is rated almost twice as good at twice the price. That is the card to go for if you have a bit extra moolah. For now, this is enough to help weed out the bad products.

List of the amplifier chips used in some studio monitor speakers - thoughts

List of the amplifier chips used in some studio monitor speakers

Pro-audio is one place I expect to find balance of component performance. Because with so many competitors as well as using measured numbers to reflect performance, it is about the best performance for the same money, at least on paper. And to do that, bottlenecks must be minimized, and the performance of each part matches the performance of the rest.

With so many gainclones being used, this makes me wonder about the performance of T-amps and such.

Gainclones aren't bad, in fact they perform very well for the price.

And that is actually the problem. Look at the number of LM3886 being used. And usually two of them are used for a bi-amp configuration.

And take a look at the amplifiers themselves:

(Source: Everywhere on the internet, I just visited webpages that were given to me by Google Image Search, if you demand credit or need it removed just inform me)

M-Audio BM5A


Mackie HR824

Yamaha HS80M

ESI nEar05

Tannoy Reveal 5A

Genelec 8050A

Behringer B2031A

I could go on forever, but you should get the idea already. Even if we ignore the complicated preamp section, looking at the power amp sections themselves, well they are not fancy with multi-colored components and "magic materials" or what the ****s, but they certainly are no slouch either. Well you can see some amps being bigger than others due to price differences of the speakers, and some amps more worth the money than others, but in general, a 2xLM3886 amp, complete with parts of those size, costs quite a bit already materials alone.

I don't expect cheap gainclone kits to do any better. Or even the same, those cheap kits using cheaper or fake chips and tiny capacitors.

And that is the problem. If pro-audio designers are using this quality of gainclones with their $300-1000 active speakers, then passives speakers in the $300-1000 range should demand even better amplifiers.

And Creative T20 Series II and T40 using TPA3123D2 and TDA8932 respectively tells more about the value of these amps.

Now I'm doubting that <$100 amps are sufficient.

Random thought: Hearing loss and frequency range

Since I was doing a frequency sweep might as well check my hearing.

Reliable detection - 18kHz. Don't know at how many dB down. Not bad considering my ailment. Might have dropped I dunno, I can't remember my 18kHz loudness from last time, and it can be due to equipment. (The Atom's 18kHz is rather high compared to the Diamond 8.2's)

Just to make sure I also did all the way till 14kHz in 1kHz intervals. I'll never understand how the ear interprets these high frequencies.

But one thing in common as I listened to all those tones.

They all sound like ****.

They are meant to be a screech alright. But the similarity...

That is when this struck me. A basic concept in music and acoustics that had escaped me. (Well because nobody mentions this during discussions involving hearing range, because hearing range translates into phallus size.)

The octave.

The ear differentiates tones by their relative differences.

An octave = doubling of frequency
A semitone - 1.059463 times frequency

So, if we take 15kHz as the reference,

A person with an over-perfect upper limit of 22.5kHz can hear 7 semitones higher, also equals to a fifth (e.g., C to G), or 1.5x frequency
+6 semitones = 21.2kHz
+5 = 20.0
+4 = 18.9
+3 = 17.8
+2 = 16.8
+1 = 15.9
0 = 15.0
-1 = 14.2
-2 = 13.4
-3 = 12.6
-4 = 11.9
-5 = 11.2
-6 = 10.6 = 1 octave lower than 21.2

So even if your hearing range has deteriorated until the seemingly bad 10.6kHz, you have only lost 1 octave compared to a small child.

And human hearing range has 20 to 20.5kHz = 11 octaves to start with.

So you would've lost 1 octave out of the original 11.

Big deal.

This argument supports the phenomenon that musicians and old listeners, although their hearing range could have deteriorated to below 10kHz, it is a relatively minor handicap and their experience more than makes up for it to make them better listeners.

(Note: This is partial bullsh!t. Yes the maths make sense, but you can try the effect of a high-pass filter via a parametric equalizer and cut the highs at different frequencies and see the result. It is not unnoticeable.)

Lord praise the guy who invented Li-ion

...Or we would still be using 3 NiMh cells and getting two hours of runtime out of hand-held gaming consoles.

Now if only someone can standardize the form-factor of Li-ion cells, may lord praise him too.