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jellyfish420
01-28-2005, 01:25 AM
what is the actual sound difference between 1 bit D/A and 24 bit? what do the bits do?

audiolife
01-28-2005, 01:30 AM
transfer of information. 1 bit does it 1 bit at a time 24 bit 24 bits at a time. depending on the recording you can tell the diff. if all you listen too is fat joe or the eastside boys i doubt you could tell the diff.

Shugarra
01-28-2005, 01:38 AM
Okay, no way in hell I could explain it correctly, so I'll just send you to a link, you might have to sign up for the message board, but it's worth it:

http://forum.elitecaraudio.com/showthread.php?threadid=95760

1 bit isn't necessarily worse than 24 bits, by the way.

johnecon2001
01-28-2005, 01:43 AM
uhh.. I don't think thats correct. But I'll ask around to be sure.

I know 1bit D/A is not the same kind of thing as 24bit.

audiolife
01-28-2005, 01:46 AM
it depends on what you do with it after the deck........

Shugarra
01-28-2005, 02:47 AM
Found a more direct thread: http://www.elitecaraudio.com/forums/showthread.php?threadid=77493&pagenumber=1

I'm going to copy and paste the part about bits in the ADC process but I want to be very clear that the only part I had in this information was the copying/pasting part. All credit goes to Werewolf.

So far, we have only 'sampled' the analog waveform. But we rest assured in the knowledge that, thanks to Mr. Nyquist, we have not yet introduced ANY ERRORS ... because later on, we can completely recover the signal from it's samples. But those samples are still kinda analog ...

So now we do the true analog-to-digital conversion process, and convert these 'kinda analog' voltage samples to DIGITAL WORDS (yes, we really do call 'em words). We will see that this process ... called quantization ... does in fact introduce errors (and believe me when I tell you, a person could EASILY devote an entire career to the study of quantization).

What better way than to proceed with an example? And we'll ask for our very first homework assignment shortly Let's say we have an analog voltage waveform that spans the range from 0.10 volts to 0.90 volts ... can take on ANY value between these two limits (chosen for simplicity). Furthermore, let's say we want to build ourselves a 3-bit ADC to "digitize" this waveform (OK, so 3-bits doesn't sound very high-end ... but I caution you to not judge this book by it's cover ... plus it's alot easier as an example).
So here's how the converter will work : if the analog voltage sample (let's say we've done the sampling described above) is BETWEEN 0.10 and 0.20 volts, we give to that "analog" sample the "digital" word : 000 . If the analog voltage sample is BETWEEN 0.20 and 0.30 volts, we give the analog sample the new digital value of : 001 . So let's construct the followng table :

Analog Voltage Sample Value Corresponding Digital Word

0.10 --> 0.20 000
0.20 --> 0.30 001
0.30 --> 0.40 010
0.40 --> 0.50 011
0.50 --> 0.60 100
0.60 --> 0.70 101
0.70 --> 0.80 110
0.80 --> 0.90 111

So here's an example : analog voltage sample of 0.37 would be assigned a digital value of : 010. But please note, that an analog voltage sample of 0.34 would be assigned the SAME digital value ... so here, for the first time, we introduce an ERROR ... called (cleverly) QUANTIZATION ERROR, or (somewhat incorrectly, but vastly used), QUANTIZATION NOISE.
In the case of my example of 0.37, the actual quantization error would be 0.02 ... because we "expect" the digital word 010 to correspond precisely with the analog voltage halfway in it's region, or 0.35 (and 0.37 - 0.35 = 0.02).

So why would anybody put a precious analog signal through such a "noisy" process? Because, once the signal is digitized into these digital words, it is (virtually) immune to further errors in storage and/or communication (this is the essence of why we like digital). And if we use ENOUGH BITS to quantize the signal (more than 3), the quantization noise will be very small indeed ... much lower than other forms of noise that plague analog storage & communication.

How do I build such a converter out of real circuits? Well, the type of analog-to-digital conversion described here is pretty straightforward to build. I might start with a 1 volt voltage reference, and use a resistor-divider chain to establish all the "boundary" voltages (0.1, 0.2, etc), creating a series, or bank, or array of voltages. Then I use a series of comparators, all of which have one input tied to the analog signal, and the other input tied to one of each of the voltage references. The comparator outputs will tell me what digital word to assign to the analog input. Make sense? The whole key, however, for this process to work is this : I must VERY ACCURATELY establish ALL of these "boundary" voltages, to compare my signal against.
And if you think that this technique, for 16-bit conversion, means I must establish voltage references that are PRECISE to within ONE PART in 2**16=65,536 ... that's where you would be RIGHT. A VERY difficult challenge ... more on this later.


He goes on later to explain how a 1 bit process can be just as good or better than a multibit decoder so long as the proper oversampling is used.

m()nk3yb()y
01-28-2005, 04:10 AM
If you are into the nitty gritty parts of audio, especially digital audio, read that post. Werewolf knows his **** for sure.

desertheat
01-28-2005, 04:41 PM
Exactly, I currently use 1bit burr browns in most of my very very high end home audio gear and still in my car audio gear. People that bragg about there 24bit d/a converter usually have no idea how a dac works in the first place. They just think because it says 24 on it and 24 is a higher # than 1, that there 24bit dac is WAY better... to funny to me :) Eclipse owners do this all the time, bragging about there 24bit dacs and how superior they are to everything else, not knowing that the same dac they use is found in many $150-$200 decks. Not saying eclipse does not make a fantastic deck, but that should not be the feature they bragg about the most :) Ok bring on the fire hahaha.

desertheat
01-28-2005, 04:56 PM
I like this section also...

The real benefit of a one-bit converter is this : mismatch can only cause a harmless gain or offset error ... one bit means only two values or "points" on a curve, and two points define a straight line, pure and simple (it's deviations from a staight-line transfer function that cause distortion).

So the analog signal first passes through a GRADUAL analog anti-alias filter, which just needs to provide healthy attenuation by 3Mhz. Next, the signal is sampled at maybe 3Mhz (or higher), and then digitized by an algorithm very similar to the one you guys built. In short, yes it's only one-bit ... and hence very "noisy". But the algorithm is designed to make sure that the noise is "shaped" in frequency so that the noise is VERY LOW in the low frequency band of interest (20kHz). This is why even simple averaging, like what you guys did, "reveals" the high resolution possible ... averaging is a form of low-pass filtering, which in this case "removed" alot of the one-bit quantization noise at high frequencies.


In fact, the one-bit signal is then sent to a DIGITAL low-pass filter, not unlike the averaging process you guys did. This is interesting ... it's really this digital filter that : removes most of that one-bit quantization noise, "revealing" higher precision digital words, and ... get this ... provides the SHARP anti-aliasing needed before the final step of "decimation" ... which is simply lowering the sampling rate (a sampling process itself) back down to 44.1kHz Yes, a digital filter provides the real sharp anti-aliasing needed for 44.1kHz samples !! Why do we like a digital anti-alias instead of analog? No component drift, no chance of power supply noise creeping in, and finally ... can be implemented as FIR with perfectly linear phase By the way, an FIR filter is really NOTHING MORE than a "weighted" averaging filter, that takes a running average of many (much more than 64) one bit samples to produce a higher precision digital word. And as a nice bonus, it turns out that the computation required for the FIR is not bad at all in a decimation environment ... since there's no feedback in this filter structure, you never need to calculate the outputs you're going to ignore after you downsample to 44.1kHz So that's it, the one-bit bitstream is digitally filtered by a long FIR lowpass filter, generating higher precision digital words ... and we only need about every 64th word (after filtering) to supply the 16 bit words at 44.1kHz





Why do ya think alpine never went away from 1bit..?? hmmmmm :up2somet:

3.5Max6spd
01-28-2005, 05:55 PM
I like this section also...

Why do ya think alpine never went away from 1bit..?? hmmmmm :up2somet:

Ever notice how extensive Alpine's DSP is? The Eq dept is lacking for a reason in comparison tho say Pio's 20 bit and Eclipse 24bit units- there's a limit to how much processing a 1bit DAC can handle after the lazer pickup without sacrificing the digital source quality- larger DAC's can handle this more efficiently...

desertheat
01-28-2005, 06:26 PM
Ah so you are saying that all of the time alignment and crossover functions are handled directly by the adc and dac and the adc and dac are what processes the crossover and time functions..?

Nope they are not. It is a totally seperate processor and a 1bit dac or adc is MORE than capable of taking care of the changes in the audio signal made by the seperate processor.

No matter what, the adc is handeling what comes off the disk and the dac is handeling the audio after the signal is processed for time / crossover functions. Because the sound is processed before the dac, it does not matter that it is still a 1 bit dac.

That would be like saying a cd recorded with alignment built in the recording or frequencies pre crossed over "on the original recording" would be to much for a 1 bit dac to handle, sorry it is simply not the case. :)

I have talked to alpine engineers on several occasions and the ability to add several more bands of eq, mor eq ability and even steeper slopes is 100% there, but they will not do it for **** stupid reasons and tell me that more will come with later versions... darn deck nazi's grrrr

desertheat
01-28-2005, 08:11 PM
transfer of information. 1 bit does it 1 bit at a time 24 bit 24 bits at a time. depending on the recording you can tell the diff. if all you listen too is fat joe or the eastside boys i doubt you could tell the diff.


I would give you my whole system if you can tell the difference on a recording between a well made 1bit dac and a 24 bit dac. Sorry man you just will not hear the difference.

But is there anything wrong with having a 24bit dac..? Nope, anything wrong with a correctly built 1bit dac..? Nope... Both are great if built and deployed correctly and both will sound perfect to 99.9999999999999999999999999999% of everyone on the planet except the self proclaimed "super ear" retards that claim to be able to hear the difference of a cd player when it is tilted or set flat hahaha.

In closing, pine, lips and pio make steller decks and all should be considered "audiophile" grade when it comes to car audio.

audiolife
01-28-2005, 10:41 PM
i gave up my 1999 top of the line eclipse for what i have now simply for going all digital and at the time there was a difference plus with what i have now i can do everything i need 1 time in 1 little box not to mention when you run fiber out i bypass my decks dacs anyway. now granted its still bigger than 1 bit but from what i understand 1 bit when it get processed is more likely to shift out of its normal range and allow/not allow changes . if there wasnt any more to it then why did the company that basically fought about the goods of 1 bit go to 24 bit when they went with the onboard digital processing? i have read in sooooooo many factions that fight one way or the other but to this day i have yet to hear a high quality 1 bit process of dsp. when you have that much control literially a 1 bit wont do it as well.

desertheat
01-28-2005, 11:09 PM
You guys are getting onboard processing confused with your output dac, kinda like getting your processor confused with your nothbridge on your pc :) With your fiber optic, it is only as good as your adc. Both 24 and 1 bit are fine. Again you will not be able to tell the difference as much as any of you want to be able to :)

audiolife
01-28-2005, 11:26 PM
ok then tell me why they dont use 1 bit dac in a serious digital processor. eclipse has 1 bit down pat i wont argue that but on their high end decks they are 24 bit, the alpine f1 24 bit, sony es 24 bit even the p1 or was it the p9? pioneer 24 bit pioneer odr was 20 bit and 24......why did a dry sony es c -90 sound better than my eclipse? no processing (i wasnt running balance out but thats about as big of a deal as 1 bit vs 24 bit)

audiolife
01-29-2005, 11:57 AM
You guys are getting onboard processing confused with your output dac, kinda like getting your processor confused with your nothbridge on your pc :) With your fiber optic, it is only as good as your adc. Both 24 and 1 bit are fine. Again you will not be able to tell the difference as much as any of you want to be able to :)
nope on the on the confused part on a processor like that each set of channels needs its own dac and it would be more like a multi processor mother board vs a single processor motherboard. last time i checked a dac worked as a dac.

paikiah
01-29-2005, 12:19 PM
i think both yours and my C90 uses 20 bit burr-brown, not 24bit. 24 bit alpha processing mumbo jumbo was introduced into the car audio worl by denon to alpine initally for their F1 line (if i'm not mistaken), then said screw it and introduced their own line of decks.

My home meridian G08 CD player has a 24 bit DAC i think. I was thinking about having a CD transporter and dedicated DAC, then decided not to. I don't think it'd have made an audible difference, only a more expensive system and a huge dent in my wallet.

However, due to idunnowhy reasons, the same CD played on the meridian was much better in quality than when I played it on an old laserdisc player that "brags" a 1 bit DAC.

audiolife
01-29-2005, 12:22 PM
i was speaking of the xdp4000 x as the 20 bits in the c-90 are bypassed when you use the fiber optic out i might be wrong here but iirc the xdp 4000 uses either 20 or 24 bit crystal dacs

paikiah
01-29-2005, 12:22 PM
oh, and the C90's "digital" output is really SPDIF so it isn't true digital signals as such. It's converted first from digital to analog in the deck itself, then converted to a digital signal AGAIN to send to the processor ( 4000x in your case, 210eq in mine) where the processor has to decode back to analog AGAIN. :P all this converting can't be good...

well, at least using that will rule out alt noise picked up via RCA's.

paikiah
01-29-2005, 12:24 PM
i dunno what sort of converters the sony processors use, but i'm sure sony didn't cut corners in making the 4000x. Whatever the number of bits and whatnot, higher numbers sell. If it seems to make the system sound better, then it's working. Don't matter if science says no.

audiolife
01-29-2005, 01:24 PM
im going back a few years here so if im wrong or clouded here forgive me but the way i understood it was to do the processing multiple bit above 16 should be used. so with all the adjustments you could make actually go to that value of adjustment where as if it were single bit it could cofuse your setting for another value and not do what it was set to do. i have the schematic of the xdp-4000x and on each output it does have its own dac. i might be wrong with this concept as of technologies now but as it concerns this peice this is how i was sold on it. digital as a whole is pretty basic especially breaking it down. only hard part about it to me is going back to the basics and brushing up on classes i took 10 yrs ago in college. busting out the bread board again would be fun though lol.

desertheat
01-29-2005, 01:30 PM
Most likley because your old laser disk player only sampled at 44.1khz. It is in the oversampleing that makes a 1 bit dac shine. I will not argue with you guys on what is better or what is not because people that are set in there ways are like talking to a brick wall. I have nothing against a 24bit dac so do not get confused, I am stateing facts about a 1bit vs a 24bit.

My offer still stands, if you think you can hear the difference between a 1 bit dac that samples at 8X/352.8kHz that alpine uses and a 24bit dac like in the eclipse decks or $150 cheapy clarion deck then I offer you my whole system if you can actually hear a difference. Fact is you will not be able to tell period and do not tell people that there is a difference when there is not.

Also 24bit dacs are not all the same, that is like saying "this car puts out 400hp so it should be exactly as fast as this other car with 400hp" Sorry does not work that way. The dacs eclipse are useing and other brands are super cheap and nothing near the quality of a high end home audio unit so the comparison is not even close. Just like the 1bit in a new alpine deck or even an alpine in 2000 like the 7949 with 1 bit dacs is lighyears better in quality than an old laserdisk players 1 bit dac with crappy sampleing rate.

I understand you want to make it an eclipse vs alpine war but that is not what I was talking about. Both make steller decks and both choose different paths for sq. Just annoys the heck out of me to hear people that talk a big game and think they know allot about audio make outlandish claims like 24 sounds better than 1 and you can hear a difference, well mabey if your deck your comparing it to was made in 1989 vs a 24 bit setup made in 2004 :)

audiolife
01-29-2005, 02:19 PM
eclipse vs alpine war? i have a sony and i simply tried to reenforce what i said up at post #5 if you are going to process it in the digital realm higher bit should be better. if it can be done with single bit then someone would do it, but as of now ever digital car peice that actually does processing that i know of that is each companies best peice sony pioneer alpine and eclipse (reason i brought them up is because they are basically the ones who brought 1 bit is as good as multi into the car audiofile world yet their all in 1 head units which do the processing im talking about are 24 bit not single) has at least a 20 bit dac on each set of outputs. also on another note in i know this is old but we had a couple of alpine 7909 rereleases (98?) and that flat out whipped tail on the 7949 i think (dont sell nor use alpine anymore) and it beat all the others too. i put all the alpines in our board so i know how they were hooked up no funky stuff either on our reps "alpine" sound off cd there was a pretty large diff maybe it was the rest of the guts but out right it sounded better until u took the other and hooked it up to its dsp. personally in analog there really isnt alot to drool over anyway as far as better sound till we get to speakers.....

audiolife
01-29-2005, 02:36 PM
If ever there was a need for 24 bit DACs in consumer digital audio, here it is. Easiest way to understand is : say you start with 16 bits from the CD, and you want to attenuate by 6dB. Well, that's one bit shift right. So now you've got a 17 bit signal ... if you've only got a 16 bit DAC, you have to truncate the LSB ... in other words, lose precision. Even with proper dithering of the truncation (good practise in any case, more later) ... giving up bits = unhappy camper. Anyway, I think the top Eclipse deck uses this method. But rumor has it that they use a pretty fine DAC inside ... the very same Crystal CS43122 that floats around this neighborhood on a little evaluation board

3.5Max6spd
01-30-2005, 03:17 PM
Anyway, I think the top Eclipse deck uses this method. But rumor has it that they use a pretty fine DAC inside ... the very same Crystal CS43122 that floats around this neighborhood on a little evaluation board




The dacs eclipse are useing and other brands are super cheap and nothing near the quality of a high end home audio unit so the comparison is not even close.

If anyone is making this an 'eclipse vs alpine' war......its desertheat- you are ASSuming Eclipse's Crystal 24bit alpha processing DAC is not up to par-your beef
with eclipse decks is apparent from this, and other threads. I say be happy with your 9835 and stop flaming Eclipse products, you seem to have some sort of inferiority complex and become defensive when people list Eclipse decks attributes- only you would see it as 'bragging'....

It is what it is....

audiolife
01-30-2005, 03:25 PM
i agree only thing i was doing was listing brands that offered the processing we were talking about. in no way was it to start a this vs that war as i never stated which was better or not. i just used the eclipse decks with the built in dsp as a 24 bit example. i dont come hear to start arguements nor do i come here to beat my chest and to be honest i didnt go into this thinking i was the shizit like some people talk. if im wrong so be it but in general terms if i say it i was probably shown it at least by a rep.

desertheat
01-30-2005, 07:17 PM
If anyone is making this an 'eclipse vs alpine' war......its desertheat- you are ASSuming Eclipse's Crystal 24bit alpha processing DAC is not up to par-your beef
with eclipse decks is apparent from this, and other threads. I say be happy with your 9835 and stop flaming Eclipse products, you seem to have some sort of inferiority complex and become defensive when people list Eclipse decks attributes- only you would see it as 'bragging'....

It is what it is....


Sorry man not the case at all, if you actually read my posts instead of mabey a line or two you would see I actually compliment eclipse decks many times, they are great peices of gear "03 and 04 models only IMO". What pisses me off is when eclipse owners start telling everyone how "much better" eclipse sounds and then start talking about there super cool 24 bit processor that sounds so good you can hear the difference between other decks and the eclipse. That is the only beef I have for I think it is retarded and total BS which it is.

Please show me were I flame eclipse products other than stateing a fact that the 24bit dac in an eclipse is the same cheapy dack as in a low level clarion "fact" since you posted that I am flamming eclipse decks, please list all the flames! would love to see what you call flamming!!!! And again if you can actually read what I said, the 24 bit dac in an eclipse is fine and equal to many 1 bit dacs out there, not worse or not better. Once you actually read my posts then come back and talk.

All I said that got everyone going is that a 1 bit dac is awsome if implemented correct and had the right oversampleing "alpine does which is why they did not need to switch to a 24 bit dac" Once you rear all my posts from the beginning you might understand what I am talking about.

jellyfish420
01-30-2005, 07:26 PM
guys....i didn't start this thread to fight:(
i just want some good sound.......
and the best decision is a knowledgable decision.
if i wanted to hear all the bitching i would go in the
other room and sit w/ the wife! :mad:

desertheat
01-30-2005, 07:29 PM
In short Jelly, Get an eclipse, get an alpine or get a mid to high level pio and you should be more than happy and you will not be able to tell a difference between one unit that has a 24bit dac and one that has a 1 bit dac. Choose the features you want, choose the looks ya want and then the brand name ya want and you will be set man!

paikiah
02-01-2005, 12:41 AM
so apprently some diehard fans of the C90 got to me and told me what I said about the C90 isn't true. If it matters to anyone, it's not true. Does that even make a difference now? :P

audiolife
02-01-2005, 12:42 AM
so apprently some diehard fans of the C90 got to me and told me what I said about the C90 isn't true. If it matters to anyone, it's not true. Does that even make a difference now? :P
yes now go to your room. lol jk :laugh: this stuff isnt to be putting anyone down or who is right or wrong to me its about learning and apply nothing more or less

paikiah
02-01-2005, 12:49 AM
was it you in the other forum? ;)

audiolife
02-01-2005, 12:55 AM
no but i read it. i talked to the es man himself before i bought it. it was a semi big deal as i was gonna redo a car and go back to finals but i let women get to me first lol. i just tried to make sure it was as good as advertised thats all. the week after i bought this i met the biggest mistake in my life

paikiah
02-01-2005, 12:58 AM
lol~
funny how the world goes round.

Anyhow, I think after trying out a few more equipments in cars, I'm gonna hang everything related to car audio up and get deeper into home audio. Still fresh trying to "tune" the living room to extract more from what I have.

audiolife
02-01-2005, 01:08 AM
home or car its all good one thing i still cant get over though is how companies sell 20k speakers and higher. to my ears klipsch big horns and system audios (all sell for alot less) sound every bit as good for alot less $$$. there is this one guy up by where i live who only buys extravigant (yet old schoolish meaning a simple pair of towers, 2 tube amps a tube preamp, some $5000 cables and a tube cd player) and from his speaker sets i cant tell too big of difference except the enclosures look like something straight out of some failed geometry experiments lol. dont get me wrong it sounds nice but when you start spending 10k and up on 2 speakers and get little to no diff you gotta wonder. if i could remember his equiment names you would without a doubt know them but as a whole they are "underground" companies you buy direct from.

paikiah
02-01-2005, 03:37 AM
You trying to imply something bad about my cremonas?

:readytog:

hehe.

Before I bought my home audio, I wasn't sure that a listening room would make THAT much of a difference, but I was so wrong.

I'm sure in a proper room, a budget $1000 system would sound much better than a $10G one.

Curious, what's this about horns? I'm now looking around for some high efficiency speakers to match my tubes for the bedroom.

And no, I don't use $5000 cables. :)

audiolife
02-01-2005, 03:53 AM
http://www.klipsch.com/product/list.aspx?line=1259&type=All

there they be system audios are sweet and skinny prolly the lightest cones i ever seen VERY suprising sound i might add. for about 2 grand id have me a pretty good stereo set im not into the surround thing yet. lol the klipsch look like 2 ways we "ordered" them but i only heard them 2 times (our rep wanted us to push the synergy) but those heritage horns are awesome. i am a horn geek though. www.system-audio.com floor standing sa 1550 are sweet

paikiah
02-01-2005, 03:57 AM
I am against surround sound at home. I always say, if you want cinematic experience, go to a cinema. :)

I'm looking for horns cause the old tubes only produce about 25w or 30W (not so sure, would need jack frost the tube maniac to verify) per channel.

Oh, i love the sound tube amp systems. Say what you want, but I say tube amps make things sound so much smoother. Not very useful with R&B though. Bass seems to feel soft..way too soft. :P

audiolife
02-01-2005, 04:00 AM
depends on my mood but i always go back to solid state although when im 60 im sure id own a simple tube set up just so i cant get volume happy lol