A/D Converter High Res No high pass

Ryan Murphy said:
Actually it is you that do not understand at all what i am saying. I hear you you don't need 786khz resolution for bass. But what you seem to be failing to understand is that I am not just recording bass here. I want that high resolution digital clarity, and I want my bass to come through also. I don't make CD's, so I don't need 44.1khz.

I'm pretty sure they have these HPFs hardwired in so as to not blow the equipment, or muddy the signal.

Almost everything works on Linux as dose Windows or Mac. This is not the issue here. I can go back to an LTS linux like UBuntu Studio and that Edirol will work fine.
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Using a 786kHz sample rate for more clarity in an audio recording is like using a turbofan engine from an airliner on your car for more performance. It's just about the most useless and counterproductive thing you can do.

People who design this gear aren't idiots. They don't filter out low frequencies to the point that it impacts the ability of the system to capture bass.

But you seem to think you're the expert, so I'll just let you carry on with whatever it is you're trying to do. Good luck.
 
I'm not sure what made you think that super high sample rates will give you any more than the ability to record sounds that even bats can't hear, but that is all it will accomplish.

The only hard wired high pass filters in audio interfaces are below 20hz, which will be below what a bass produces, what your playback system is likely capable of reproducing, and below what you can hear.
Unless you are running laboratory tests on air pressure waves, and not trying to record musical instruments, your sample rate is ridiculously high. Unless there is something broken on your interface, it is not the reason for the lack of low end.

If you could tell us what you are doing and how you are doing it, we can help get you on the right path.
 
The range of human hearing is generally considered to be 20Hz to 20kHz. These are the extreme limits, 20 Hz being a low rumble that's felt more than heard. Low frequencies take more power to reproduce and many typical speaker systems don't go that low unless you have a subwoofer. Even with a subwoofer, extremely low frequencies don't provide us with much useful information in the frequency spectrum. It's common for people mixing bass instruments like guitars or kick drums to use high pass filters with a corner frequency of 80 to 120 Hz. As counterintuitive as it seems, this often has the effect of cleaning up the low end and allowing the perception of more bass. Most "bass instruments" will have harmonic content that reaches through the midrange to support the sound. An exception would be if you're trying to reproduce sine waves at extremely low frequencies. A sine wave is a pure tone with no harmonics. Essentially you would need monitors (and all other parts of the chain) capable of reproducing those frequencies.

It's fairly easy to get a digital converter flat down to 20 Hz. It's the one part of the chain that shouldn't have any problems at that low a frequency. I'm not sure what a MOBO mic input is (motherboard???), and there was never any mention of a specific microphone. Many mics can reach down to 20 Hz. Some can't. If you're trying to record with the built in soundcard of a computer, that could have all kinds of problems associated with it that any audio interface designed to connect to musical instruments and microphones should vastly improve upon.

That "high resolution digital clarity" thing does (<-sic) NOT come from sampling beyond the range of human hearing.

Any chance of laying down that jazz groove on a double bass?
 
Yeah the caps in the signal path are all about keeping control of your DC conditions. A smallish DC offset at the input isn’t going to hurt anything, though it could cause pops when switching. But if there’s gain in the circuit, that small DC offset gets multiplied along with everything else, and can pretty quickly ram your signal into the rail, starting as asymmetrical clipping but at the extreme it just goes to the rail and stays there because the requested DC output is far enough above what it can actually put out that even the bottoms of the waves don’t fall below it.

One thing about this is that it can’t support true asymmetry in the input. Asymmetry looks a lot like DC offset, but the caps can’t let that happen, so the signal either floats to where the average is 0 or else gets phase rotated in a way that it won’t really sound different, but also won’t look the same.
 
And! If anyone has come up with a DC coupled mic pre amp with phantom power I would LOVE to see the schematic!

Dave.
 
Ryan

I'm seriously confused by your comments. You talk about not wanting a Hi Pass Filter. The RME had output bandwidth @ 192 kHz of -1 dB: 0 Hz – 88 kHz. Input bandwidth is -1 dB: 2 Hz – 92.7 kHz There's not a bass on the planet that can produce 2Hz. I also can pretty confidently say that there's not a person on the planet that can hear 88kHz. There is no high pass filter used if you can read 2Hz signals. Certainly it's not going to bandwidth limit your bass!

You then talk about using Bluetooth 5.0, which has a maximum quality of approximately CD standard under optimal conditions. You also talk about transcoding for video at 96kHz Oog Vorbis, which is not even a bitrate for a compressed file. You might be encoding at 96kbps, but there is no 96kHz rate. In fact, at 96kbps, you are losing bandwidth below 20kHz. I think 128K MP3 is about 15kHz, equivalent to FM radio broadcast. The Vorbis will be in that same range.

It sounds like you are trying to make judgements based on numbers which are measuring different things. 320kbps compressed formats are not the same a 320kHz sample rate. In PCM format, a 192kHz/24bit file is running at 4.6Mbps with a bandwidth up to 96kHz. I can't imagine recording at 768kHz sample rate (18Mbps) per channel.

In short, the math just doesn't add up.

Maybe you need to describe how you are recording your bass and synths. Something is seriously wrong if you need more than 30dB boost on the bass.
 
TalismanRich said:
It sounds like you are trying to make judgements based on numbers which are measuring different things.
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You know, I think you may be on to something.
 
ecc83 said:
I am far from any expert in digital matters but find a proper one and they will tell you that the "resolution" of digital recording is 6dB per bit and that decides the noise floor...Nothing else. The sampling rate determines the highest frequency you can record which will be a little under half said rate.

That is all. I shall leave you to it.


Dave.
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Your thinking this thing all wrong.... I already know 24 bit is max bit depth etc.... That is full digital spectrum, but your taking this whole resolution thing = highest possible recording freq attitude is a little closed minded. It is not at all as that simple as it is. Think of it like dpi on a monitor. They are both 10 bit HDR monitor so you get the full color range, but the 4k monitor is going to be much much more detailed of an image than a 1080p just like a 768khz 24bit audio recording will have much much more clarity than a 44.1khz. It is not just highest freq possible. Think of your speakers, and ear and brain as a low pass filter. Now the higher resolution audio is going to sound much better through that low pass filter of your brain.

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TalismanRich

I haven't bought the RME ad Pro2. I just don't want to spend 1,500 dollars on something and have it not be able to pick up my bass or VCO's.

Bluetooth 5.0 has aptX. I heard that is lossless. Anyway i listen to a lot of vinyl and have amps hardwired so I can play anything. I'm trying to get enough good music together to press a vinyl perhaps. I'll probably go with a half inch tape machine anyway becasue it is cheaper than the 1,500 dollars.


*** and as far as bass goes. i want to be feeling it on my chest.


That infra sound video posted. I couldn't hear anything bass wise going on outside the normal kick? They didn't seem to line up. Is there anything i am missing or do i need to send a wire to the amp as opposed to streaming it wirelessly.

testprojectmain out.flac - Google Drive

Compare the 96khz Vorbis Audio to the 384khz flac. See if you can output 384khz audio. I've never heard nothing that clear from a CD. Just saying. Try using a HDMI video card or Display port digital audio out from a monitor. Tell me if it makes yourt amp crackle. It sounds great through a wire to a H20 Jacket Bluetooth speaker, but crackles the speakers a little. I have to hook it up to the tubes for optimal playback.

Do you guys have VCO's? That synth is more bottom heavy than that. It is almost indistinguishable the right hand stuff, but is ever so slightly thicker.

I added the bass running through this little pre amp before mobo
20200902_174519.jpg

bouldersoundguy said:
Using a 786kHz sample rate for more clarity in an audio recording is like using a turbofan engine from an airliner on your car for more performance. It's just about the most useless and counterproductive thing you can do.

People who design this gear aren't idiots. They don't filter out low frequencies to the point that it impacts the ability of the system to capture bass.

But you seem to think you're the expert, so I'll just let you carry on with whatever it is you're trying to do. Good luck.
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I don't know why you are taking this hostile approach and claim that I claim to be an expert. I am merely asking a question here becasue what i currently have is not producing enough bass. I also noticed that alot of a/d converters have built in HPF's, so I don't want to buy something and be having the same problem. I also thought the idea of owning a 768khz a/d converter would be cool, but I need it to bump if you know what i mean.
 
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Video and audio cannot be compared as far as digital "resolution" is concerned.

If you don't believe me, go and talk to the people at soundonsound.com.

Dave.
 
The sample rate does only change the highest frequency that can be recorded. It doesn't equate to "resolution".

Sample rate also doesn't work the same way as pixel number in video. It is more analogous to the refresh rate. Past a certain point, it makes no difference.
 
Farview said:
The sample rate does only change the highest frequency that can be recorded. It doesn't equate to "resolution".

Sample rate also doesn't work the same way as pixel number in video. It is more analogous to the refresh rate. Past a certain point, it makes no difference.
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Yes it dose. High resolution audio sounds more clear than lower resolution audio. The processor is creating sound 384 thousand times in one second as opposed to 44.1 thousand times. It's better for mixing, listening, longterm file storage where byte loss is an issue. All kinds of different things.

Produce a 44.1khz audio that sounds as clear and loud as the 384khz testprojectmain out.flac - Google Drive I posted above. You can't. 44.1khz just isn't enough processing power.
 
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It may be worth having a look at this video, which goes into the AD/DA conversion and how the process works. It's an interesting and informative outline of the physics involved.

 
Ryan Murphy said:
I don't know why you are taking this hostile approach and claim that I claim to be an expert. I am merely asking a question here becasue what i currently have is not producing enough bass.
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That's the problem, you ask a question then dismiss the answer and tell people they don't know what they're talking about while you're making nonsensical claims about high pass filters and stupid high sample rates. If having a 768kHz converter makes you feel better, fine, but it's a waste of resources and it won't solve the problem you came here to address. If you're having a problem with bass response (or any other sound quality issue, really) then going to 758kHz is unlikely to solve it.
 
I haven't dismissed anything. You gave me an analogy that had to do with jet turbines and cars. Someone also refused to listen to an analogy i made comparing video resolution and audio resolution to picture clarity and high fidelity. I know you guys have your books and your fancy algorithms, but the guy in the video wasn't doing anything really all that complicated either.

I have been mixing music digitally for 10 years and the higher resolution stuff I have sounds better to the ear. I have high resolution digital stuff that I have never heard on any CD. You guys have to understand this. Sampling a sign wave doesn't very many samples becasue it is simple. That is why you get perfect playback.

My solution is not to got to 768khz to resolve my bass crisis, but I want even better fidelity. I just don't want to go to 768khz if I still will unable to be able to get bass through. You guys do realize I am sending a 16 channel analog mixer with 12 ananlog VCO's a bass and one DCo w/sub oscillator through to 1/8th ananlog in mobo mic input right?

I was just trying to make sure they are just getting me not on numbers here and that there is really a HPF that is going to cut out all my low freq stuff. I do a lot of mid rang and high stuff too.



Do you rea;llize that i have bewen trying to tell you people that the mic input analog to digital convert audio on this mobo are in fact bull shit?
 
Ryan Murphy said:
Yes it dose. High resolution audio sounds more clear than lower resolution audio. The processor is creating sound 384 thousand times in one second as opposed to 44.1 thousand times. It's better for mixing, listening, longterm file storage where byte loss is an issue. All kinds of different things.

Produce a 44.1khz audio that sounds as clear and loud as the 384khz testprojectmain out.flac - Google Drive I posted above. You can't. 44.1khz just isn't enough processing power.
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This is so screwed up that I don't know where to begin.... I listened to some of the flac file. It was so ungodly noisy that you could do that with 12 bits! It had a range of about 50dB S/N max.

Frequency response is not resolution. You TV at 4K might have higher resolution, but the frequency spectrum is the same. It won't put out infrared or Ultraviolet which is spectrum or frequency response. Your Bluetooth speaker won't put out subsonic or ultrasonic, no matter how many 10 Hz waves you generate with your VCO and record at 384kHz. Neither will your Ampeg, or your "stereo monitors".

I can give you a nice 10Hz sine wave, and I can assure you that none of your speakers reproduce it. I can also give you a 20kHz sine wave, and I'm guessing you wouldn't hear that either.

If you seriously want to learn about this stuff, you need to start listening to what some of the people here are telling you. If you want to live in a fantasy world, then I suggest you forget your cheapo $1500 RME AD/DA converter, and get the $2000 black edition. Make sure you use a good interface like feed it. Behringer makes some good units that run under $100.
 
Does mobo mean motherboard?

It doesn't matter how complicated the signal is, anything that happens between samples at 96k will be above 48khz and you wouldn't be able to hear it anyway. (Thats assuming there was any sound that high in the first place and your playback system was able to reproduce it)

Seriously, I've been recording digitally since the late 80's and you simply don't understand how digital sampling actually works. What you are being told here is correct.
 
Yes a mobo is a motherboard.


Yeah, but taking 384,000 samples in one second will give you a much higher detailed picture of the sound that can not be reproduced digitally. Why do you think they are still making analog synths? and tubes. I don't know if you own any of this stuff, but what you hear on the radio is just a shadow of what this stuff is really capable of.



This sound byte here: Life in Lower East Tardieacut.flac - Google Drive uncompressed
recorded with that edirol FA 101 sound like crap when compressed to lower resolution audio. Hell they don't even make it all the way through even at 24 bit 192khz. It's not perfect. They crack a little bbit and when compressed they sound not good.

Even that 384khz recording above at times you can hear where the digital conversion fails to reproduce the saw waves.



I've got a Mackie 1642 that's pretyt awesome.
Black heh heh thats funny. Yes I did get a black case for my comp, but I haven't put it in yet. I figured it would be easier to clean. But in a world with nuclear waste flying around everywhere. Black is not worth 500 dollars for a a/d converter.

My only alteerrier motive here is get a half inch tape reel. Work on making really good music and press a vinyl using the tape; past going back to the edirol fa 101
 
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