Axiom Home Page Forums General Discussion Home Theater Has anyone experienced speakers over 23kHz

My friend recently bought Akira on blu ray, 192/24 as we all know. We got into a big conversation of is there any truth to hyper sonics at all. Accoriding to that Nyquist theorem that means it should be capable of sending frequency signals of about 86 khz, 66khz higher than human hearing! I'm curious how many of you ever experienced super tweeters capable of that, and if you ever noticed anything in such recordings. In all honesty I think it is a gimmick, even though the idea sounds interesting. Can't find much scientific info on hyper sonics unfortunately, was wondering what you guys make of it.

I think it's a bunch of horseradish, myself.

Bantha fodder is my current stance on it as well.

Higher sampling rates are not about higher frequency response, but about less aliasing though out the audible range.

Since you brought up Nyquist, yes it takes a 40 kHz carrier to reproduce a 20 kHz signal, but that signal must be precisely aligned. Think about this a 20 kHz sine carried in a 40 kHz PCM encoding, will appear the same as a triangle wave, one sample up, one sample down. If that signal shifts 90° in phase, it becomes silence. 45° cuts the amplitude in half. Only right on do you get the full energy recorded. Anti-aliasing in the down mix only serves to average the stored signal into half-amplitude also. Even a more reasonable 10 kHz signal still has pretty bad aliasing issues. But if you increase the sampling rate four fold, it's much easier to store the full energy of the signal without having to worry about exact phase alignments.

If I were recording I'd master at 384 kHz, low-pass filter at 24 kHz, and then anti-alias into a 192 kHz mix for distribution. There'd be no ultrasonic component for so-called super tweeters (nor to destabilize poorly designed Class D amps), but a very accurate representation of the original analog waveform.

I nominate ClubNeon for US Secretary of Audio Mastering.

My Marantz SR6003 cannot process the 5.1 192kHz/24bit signal from the BDP-80

It will only show 2 channel at 192kHz/24, playback the 96Khz/24bit version, have no problem with the processing....

Chris I'm not sure you make enough money where ever it is you work... I wonder how well Axiom pays their engineer team?

Quite a few receivers don't have enough power to both decode the a lossless 192 kHz, multi-channel, Dolby/DTS bitstream and apply processing.

See if you can configure the BDP to ouput LPCM instead of bitstream. Then check to see if the Marantz is still getting 192, and if processing has been re-enabled.

I still stand that BD players should only output LPCM, and do away with bitstreaming.

I would design things for free if someone would build them, and just give me one to play with.

If you're phone is ringing, it's probably someone from Axiom.

..... Or, the Russians!!!

I stick to LPCM from my Oppo, prevents any potential DTS MA bombs that are said to affect receivers that have the Texas Instruments processor. Also allows you to use Audyssey in lossless (not that I have it on now) and get the 192 in 6 channels. Only downside is you don't see those pretty DTS HD MA or Dolby TruHD symbols on the receiver

ClubNeon whats your profession, engineer or physics major? I love technically backed answers, and I too vote for to be US Secretary of audio mastering!

Seconded. I remember how bad some of the early CDs sounded until the recording folks realized that low pass filtering before sampling was a requirement, not just an interesting concept

Professionally, I'm an "IT Specialist", whatever that means. I was a double major, Mathematics and Computer Science, until I dropped out of college. But most importantly, I've been taking things apart and figuring out how they work since I was 3 years old.

That pull-its-string-and-it-talks Garfield didn't stand a chance. It was soon in pieces, with it's little record removed, and being played on my Snoopy turntable. I also took one of my mother's music boxes, placed it under the needle of said turntable, and had an amplified version of "Close to You."

Interesting. I'm also an "IT Specialist" and I used to take things apart, like those old telephones that hung on the wall that you had to crank in order to get the telephone on the other end to ring. I'd take the generators out and let other kids hold the leads while I gave it a crank. Ah, the good ole days.

But, no (very little) college for me. I got into computers through a trade school back in the late 70's. I dropped out of high school then went into the military.

I'm an IT "Systems Engineer" (whatever that title really means). Like you guys, I was disassembling and reassembling things from an early age. My dad really regretted giving me that screwdriver kid when I was five, let me tell you.

I graduated college with a degree in Anthropology. Makes a lot of sense, doesn't it?

IT Network Engineer here (see above re: whatever that means). Also disassembling things like crazy. Not so much assembling. I've got a degree in Molecular and Cellular Biology, with a minor in Egyptology.

Okay with that backround, what's a good primer for MS networks "for Dummies". WHS(Server 2003), RDP, and the "stuff in the backround". My network works fine, I can do all needed to keep it running and set it up..... but I would like to know more to increase speeds, troubleshoot, etc.

I've got a lot going on in my casa IT wise, and I'd like to know when it's network versus machine, etc

I don't want to learn it all, or go into the profession, just manage my home

I'm the wrong person to ask. I'm not so good at optimizing things--and I'm terrible at sitting down with books and studying them.

If you're really into that, I would start by getting a good foundation in how TCP/IP works. A really good foundation in that, because that's the root of it all. If you understand that, you can figure out where to start looking for troubleshooting. Optimization is a whole 'nother bag of worms.

I used to make levels for Doom haha, that's the extent of my computer expertise . Anyone remember "wad" files?

GrassyAss, I'll start there

John, anti-aliasing filters before sampling were always an essential element of the process and aliasing was never an audible problem. Distortions in brick-wall filters and failure to remove high frequency emphasis which had been used for LPs, but which was harmful with the inherently flat CD, led to some early CDs being harsh. This led to the creation of a mythical monster known as "digital harshness" which still lives in some misinformed quarters today.

Sounds like someone needs a manicure.