Thursday, September 1, 2011

HDTT responds to upsampling accusations

There has been discussion in computer audiophile forums that some so-called hi-res files are merely upsampled files of lower-quality recordings.


A website that offers hi-res files - High Definition Tape Transfers (www.highdeftapetransfers.com) - was named.


This is their response:


Lately it has come to our attention at HDTT that quite a controversy has erupted concerning the issue of upsampling in the community of computer audiophiles. Somehow, HDTT has been dragged into this controversy, and in order to clarify our position and with your indulgence, I'd like to attempt to explain a few points regarding this issue. At the same time, I would also like to take this opportunity to address certain false accusations which have been directed against us by a few individuals in the press and in the audio forums. Here are the facts:


1) HDTT has NEVER upsampled any files which we have offered for sale. Let me repeat: NEVER. There is absolutely no reason for us to upsample, because all HDTT releases are carefully mastered by us, in house, with the highest resolution that our equipment can deliver. Upsampling would provide no additional sonic benefit.


2) The "L'histoire du Soldat" controversy has again reared its ugly head after more than a year, and sadly needs additional and repeat explanation. Notably, we were accused on one of the audio forums of upsampling the "L'histoire du Soldat" release, because there was an anomaly that would show up if the file was analyzed on a spectrogram plot. We investigated this claim, and found that this anomaly was caused by a technical glitch caused by the Analog to Digital converter which we were using at the time. We immediately corrected this problem by issuing new files. However, a recent Hi Fi News and Record review article alluded to this original problem, and we were again incorrectly and unfairly accused of being guilty of upsampling. Although Hi Fi News and Record Review did mention that we reissued the files, they never bothered to contact us for comment or explanation before the article was published after that a music download site put it in there latest blog and added there own inflammatory statements. We find this to be odd, since this issue was explained on the forum at the time that new files were issued. It's difficult to understand why HDTT was AGAIN accused of doing something we never did in the first place; whether it was an attempt to make the article more inflammatory, which of course makes for a better read, is a bit irrelevant in the light of the damage it did to our good reputation. Otherwise, I can't explain why such unfair and baseless accusations might be made against us.


3) As most of our fans and customers know, HDTT is an archival business, and a modest and judicious amount of noise reduction is used from time to time to reduce noise on certain files. In some of our earlier releases, we were using a hardware noise reduction unit manufactured by a very reputable high end audio company, and we believe that on certain titles the digital "signature" of this unit was probably mistaken as a sign of upsampling. The NR unit in question was similar to the Dolby System in that it reduced noise through the use of brickwall filters at high frequencies, and to the untrained eye, this can easily be mistaken for an upsampling signature. We have issued a few titles that were originally encoded with Dolby¨ NR (Dolby was used in masters from the late 1960's to the mid 1980's by major labels), and the signature of the NR system can be seen on spectrogram plots of these files as well, but it has nothing to do with upsampling. Also, one must remember that many of the master tapes from this era were manipulated and modified before being sent to the duplicating houses. It was all too common to find on many masters the evidence of a heavy hand of equalization, compression and limiting, all of which were applied in order to make wide dynamic range material less costly and less difficult to transfer to the then-prevalent vinyl LP format. All of these post-recording effects will show up on a spectrogram as anomalous data, and the novice who is out looking for "bugs" can easily mistake their signature for something else.


We hope that this will help to put to rest any more accusations of HDTT being involved in upsampling. We don't do it! Instead of worrying about digital purity of this file or that file, we invite you to sit back, relax, and listen to the great music of the ages, which we have painstakingly transferred for your enjoyment. We believe there is no higher mission than the preservation of this music, and we wish to assure you that our task is not borne lightly or with any disregard for the original intent or value of that which the immortal artists have created for the enrichment of all mankind.


Thank you for your attention and for your consideration.


From: http://www.highdeftapetransfers.com/page/20/Response-to-Upsampling

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