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On Thursday, February 26, 2009 4:12 PM, ADRIAN COSENTINI wrote:

> Can't speak for the cassette deck, BUT for preservation purposes 
> the USB ION turntable... well... I'll stick to my SP-15, if ya know 
> what I mean. Do it right or stay home :-)

Like Richard, I wouldn't trade in my Nakamichi CR-7As for the Alesis
TapeLink USB (similar to the Alesis USB Tape2PC).  Like Adrian, I
generally agree that you should do it right the first time if you 
can because you don't usually get a second chance.

This was going to be a quick response, but mushroomed into a more 
considered reply because I think there are small archives looking 
at products like the Alesis TapeLink USB and thinking "it isn't 
perfect, but it could do the job".

So my goal here is to provide guidance on the types of projects 
the Alesis TapeLink USB and other products of its ilk are 
acceptable for, and which  projects they should not be used for.

Starting off with specifications:

http://www.alesis.com/tapelinkusb

Specifications are often tweaked and "interpreted" differently by
each manufacturer.  Some are more strict and open in their 
intepretations, and others are more liberal and provide a single
number without any description of how it was derived.  So 
specifications as stated by a manufacturer should always be taken 
with a grain of salt.  It's usually better when the specifications 
are verified by a third-party test.

Nonetheless, manufacturer specifications are all we have to go on 
here.  I decided to use a few well-known (alas, all out of 
production) machines for this comparison exercise...

1.  Frequency response comparison:

    Alesis:           40-15000 (+/-3 dB Chrome)
    Tascam 122 MkIII: 25-19000 (+/-3 dB Chrome)
    Nakamichi DR-7A:  18-21000 (+/-3 dB Chrome)
    Nakamichi Dragon: 20-21000 (+/-3 dB Chrome)

    No where near the frequency response of the Nakamichi or even
    Tascam decks, but certainly plenty good enough for non-music 
    recordings, and will do a decent job with music.  In fact, I 
    wouldn't worry too much about frequency response with the Alesis 
    unless the cassette was originally recorded on a high quality 
    professional or prosumer cassette deck, however...

2.  Wow-and-flutter comparison:

    Alesis:          <0.200% (DIN45500)
    Tascam 122 MkIII: 0.040% (unspecified)
    Nakamichi CR-7A:  0.027% RMS
    Nakamichi Dragon: 0.019% RMS

    This is a key specification when dealing with music recordings.
    The Nakamichi decks are nearly one order of magnitude (10x) lower 
    (better) in wow-and-flutter, and the Tascam 5x better.

3.  S/N ratio comparison:

    Alesis:            58 dB (unspecified)
    Tascam 122 MkIII: >70 dB (Dolby B, above 5 kHz)
    Nakamichi CR-7A:  >66 dB (Dolby B, A wtd, metal tape)
    Nakamichi Dragon: >66 dB (Dolby B, A wtd, metal tape)

    Hard to really compare S/N ratio given the variety of conditions
    used to measure S/N.

4.  Crosstalk comparison:

    Alesis:            40 dB (unspecified)
    Tascam 122 MkIII:  unstated
    Nakamichi CR-7A:  >60 dB (1 kHz, 0 dB)
    Nakamichi Dragon: >60 dB (1 kHz, 0 dB)

    This is a measure of how much sound "bleeds" over from the 
    other side of the cassette (ie. how much you can hear of Side B
    while listening to Side A).

    40 dB is not particularly good, and could be a problem with 
    spoken word recordings where there are moments of silence 
    between words and cross-talk is especially noticeable.

A few more observations about the digital output of the Alesis
TapeLink USB...

5.  16-bit word length

    I'd prefer to see 24-bit, which would give better dynamic 
    range and make life a bit easier when it comes to avoiding
    digital clipping.

6.  44.1 kHz and 48 kHz sample rates

    Acceptable for most cassette projects.

7.  ADC jitter

    If you think of jitter as the digital equivalent of analog
    flutter, it would be interesting to know how accurate the clock
    is in the Alesis.  Given the poor wow-and-flutter performance 
    of the Alesis and its low price point, I have equally low 
    expectations for the clock jitter performance.


Conclusion
==========

On anything but the smallest projects, labor is the biggest expense.
The cost of equipment (cassette deck, ADC, computer, software) is
such a small fraction of the labor cost.  The poor quality of
low-cost equipment will show up in every transfer.  If you're going
to do something right, do it right the first time if you can.  It's
rare to get budget to preserve the same recording twice.  I'm 
repeating myself, but the "penny wise, pound foolish" adage applies.
So my first advice would be to go back to the proverbial well and 
get a bit more budget for something better than the Alesis TapeLink 
USB.  The extra expense amortized over the entire project will only 
add a little more cost per recording - it's generally worth it.

Assuming that the Alesis TapeLink USB would only be considered by
organizations on a shoestring budget - possibly without experienced
audio engineers to do the work - consider finding some money for 
training, too.  Learning as you go can be expensive in terms of 
unnecessarily poor audio quality.

And if your project is small, strongly consider outsourcing it to
a preservation vendor.  You'll get far better transfers for the same
amount of money as buying cheap hardware, and far less headache.

After the above excoriating remarks, I still believe the Alesis 
TapeLink USB and similar products nonetheless could have a place 
in an archive...

What I would use the Alesis TapeLink USB for:

   - making access copies (NOT preservation masters) to simply 
     review and triage your collection to figure out exactly
     which recordings really need to be preserved properly

   - providing transcribers with copies of spoken word recordings 
     from which to work, the Alesis TapeLink USB could also be 
     adequate for that.  If the audio is too poor for the 
     transcriber, machines with manually adjustable playback 
     azimuth (like the Nakamichi CR-7A) may be required.

   - preserving less important recordings, and use outside 
     vendors (or wait for more budget) for the more important
     recordings.  I'm generally a fan of hybrid in-house and
     outsourced efforts for stretching preservation dollars.

I would NOT use the Alesis TapeLink USB for:

   - preserving high quality music recordings (due to poor 
     wow-and-flutter performance and 16-bit word length)

   - preserving spoken word recordings destined for critical
     listening like books-on-tape type applications (due to 
     poor crosstalk performance)


Eric Jacobs

The Audio Archive, Inc.
tel: 408.221.2128
fax: 408.549.9867
mailto:[log in to unmask]
http://www.TheAudioArchive.com
Disc and Tape Audio Transfer Services and Preservation Consulting