Possibly - but it won’t have any bearing on the RIPs or the digital data stream. Two separate and unconnected considerations.
Google “how to calculate accuraterip v2 crc”
First hit is from Spoon the dbPoweramp creator explaining it.
There are other open source implementations in packages such as CUETools - these lookup the AccurateRip DB but don’t update, I think only EAC and dbPoweramp maintain the DB.
Despite it being a CRC the odds on two rips matching if not an identical bitstream are insanely high, such that a confidence level of 3 (3 people independently ripping on different hardware) pretty much guarantees the accuracy.
Some rippers do put an MD5 hash of the FLAC content into the rip as metadata. Tools such as ffmpeg and metaflac can generate a hash of the content to verify against this - thus ensuring the file you have contains exactly the bitstream which was ripped (i.e. not tampered with).
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I haven’t been back yo refresh my memory, but my recollection of the previous discussion I referenced is that there may be some difference in how metadata was stored, or other file info but nothing to do with the music data, and that might be the cause behind the difference. Speculation around that was that with some playing software it might affect the load on the processor, or it was even conceivable that a processor could be programmed to deliberately introduce some degradation if it didn’t recognise the fingerprint of a particular ripper. IIRC discussion about doing some detailed file analysis is where things fell down and it didn’t happen.
Thanks Iain. 
Is that a feature now of dbpoweramp?
It’s not so much the network noise from the NAS, it is about getting rid of various cables and switches, and hence any connection and cable issues, reducing boxes and also the convenience of always having the music available if I don’t have the NAS on, either all the time or scheduled.
I rip to the NAS with minimserver, then transfer to a couple of external drives using the backup function.
I don’t read that other people are doing this and given the simplicity, I wondered why not. Surely using various switched and cables won’t add anything to the signal/sound.
Thanks. That makes life easier.
For what its worth, my music server sits in my office and accesses my NAS over a smb network share. So no visible cables. The server software (roon) sends a bit accurate stream to the streamer.
We all know un wanted noise is the culprit, and if you want to get things as good as you can, then removing these or using gear that doesn’t inject as much un wanted noise into the mix is key.
Using a pc to rip is not the best, obviously it will do it, but it will not be the quietest solution as far as injecting un wanted noise into the rip.
Using a melco server is better as far as noise goes, then adding the D100 inpoves on this slightly compared to the buffalo cheap drive. But adding a better power supply improves both, especially the cheap buffalo.
As you can see from above all the differences are mainly noise inpovements, the 1 and 0 should all be the same.
Another thing is that the D100 takes much longer to rip, i believe it’s for better or less error correction it has to do on the rip, bringing again a better copy.
But we all choose what we want, and feel is needed, and that’s obviously fine.
I am glad i used the D100 with a better power supply to rip all my cd’s. I have since sold them both as i hardly need it now, i think i have ripped one cd since i sold it.
I now use the buffalo again with a better, but cheap power supply. A much better USB cable that i had (cad mk1). Plus i use isolation on the drive to help stop un wanted vibrations.
I found this works very well, and gets very close to the D100 rips i did, it’s a much cheaper option, but it isn’t as good, and if you have a big cd music collection, then i would buy a secondhand D100, and then sell it on afterwards.
Yes, it’s one of the sub-suite of apps from dbPoweramp.
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Are you closing that extraneous noise is stored in the rip?
People have no end of, erm, fun (?!?!?) playing with different network cables, switches, switch power supplies and so on, a part of which will be modifying (not necessarily stopping) the extraneous noise content of the signal, which when it reaches the DAC can cause modulation of the resultant audio. That modulation changes the sound from how it was recorded, but of course whether people prefer it pure or prefer it changed is another matter, and therefore people’s opinions as to which cables, switches etc are best very. Likewise the effect varies from DAC to DAC, and likely the entirety of their network with whatever else might be attached, and the electromagnetic environment in which is all sits. Far simpler, and better in my view, is to not stream music across the network at all, and to that end I have my player (rendering software) in the same device as the store, with just a single cable direct to the DAC. absolutely no network to worry about whether it degrades or in other ways changes the sound. Because I am interested in hearing the music as recorded, not modifying it (if I wanted to modify it I’d get myself a DSP box so I could choose exactly how I modified it), therefore if I had to have music streaming across a network a I would keep it as simple as possible, with as little attached as possible, (a different network from other things in the house). For cables I’d maybe go for screened ethernet cables but chosen purely on the basis of being good network cables, and put an optical isolator at the end where the network connects to the hi-fi equipment to isolate from noise. A DAC designed to minimise effect of noise on the signal, or modulating the ground plane would be good.
There seems to be an mis apprehension that Ethernet networks are impcitly noisy… they are not… and in fact if setup properly gives a great decoupling from noisy devices like disc drives and general purpose computing platforms.
I find network enabled streamers a fantastic way of providing simplicity and reducing noise for network streamers. Modern frame switched networks by design provide good separation and isolation of data.
Ethernet RJ45 is going to be approximately as noisy as a USB 3 interface.
Use an Ethernet enabled streamer, use the digital out to connect to an external DAC… nice and simple works superbly well, and all those woes of noise and interference are banished… and one doesn’t need to worry about noisy compute devices, noisy disc drives, electrically noisy disc interfaces and other big challenges.
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I promised a few words on the second part of the OPs question from a software engineering perspective. I will try to write something later tonight.
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Cool thanks! For fun I will play with that software though if I do detect any of my rips are not accurate, it will be a nightmare to fix as they are all packed away somewhere in the loft!!! 
I was thinking the other day that idea would be a smart idea for anyone who has already ripped all their cds with say (to pick an example completely at random 
) buffalo and a d100 to work out which cds from a software engineering perspective are not actually an accurate data match for the original pcm file used to burn the cd.
They could then rip those cds again using eac or dbpoweramp and add them to the music database and then either play which ever version of the rip gives them more pleasure or spend some happy time comparing the rips.
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Are you suggesting that somehow noise is saved alongside the data when a flac (or other) file is created through the ripping process?
Not if its rip data and that of A.N.Other are identical, as they will be if both are confirmed by AccurateRip. Slower/multiple pass ripping are purely ways of minimising read error and do improving the chance of matching the reference data - a single high speed rip may still achieve the same depending on the CD and reader, and if they don’t the file doesn’t match AccurateRip, so if checking against that more thorough re-attempts can be done, but if reader is well aligned etc that would only be needed for I in X CDs
Hi Dunc. I would invite you to read my earlier post on the software engineering aspects of ripping cds. If you have already or are not particularly interested then that is absolutely fine
I guess i am, noise is problem with everything.
I guess it’s also why i prefer a ssd, as no moving parts to inject un wanted noise.
But the how’s and why’s it all sound’s slightly different is beyond me, and i guess that goes for 99% off us. But all you can do is try things for yourself and see if it does or doesn’t work for yourself.
For me it has all made a slight difference, certainly not the night and day quote, people love to say.
Hi Dunc… no noise is inserted into rips… not sure you meant to say that… or perhaps mis understood how the process works? Noise could be created by the software or process reading the down stream file of course… but even here it will be almost certainly out of band… but may modulate clocks or analogue powerlines.
Audio CD has quite a lot of redundancy built in to allow most small data read errors to be perfectly recovered… it’s a very clever mechanism and technically it’s called data entropy… An unrecoverable data error read such as from a damaged disc however will result in silence of a few milliseconds (usually not noticeable), a static click or a skip… depending on the severity of the unrecoverable error. When a non recoverable error occurs the accuraterip indication will fail.
CD is a digital format, so you can’t marginally read data and loose things like detail as you might if it were an analogue tape… if there was a slight loss adjustment of data through reading it would typically sound super distorted or just digital noise.
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As said i don’t understand why, but it certainly slightly different.
I can 100% say if i couldn’t have heard a nothing then i wouldn’t have then spent many day’s/ hours re ripping all my cd’s with a D100. Believe me doing it once was bad enough,let alone doing it all again with a machine that took about 3 times longer to do each cd.
As said you can only try for yourself and see what you think, some say no difference, others say different. Its the same with cables, power supplies, etc,etc.
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