You've provided the detail that I was hesitant to add. Over the years,
I've noticed the eyes of recipients glazing over when I get deep into
the weeds. So, these days, I try and keep it as simple as possible
(plus, I'm getting lazier in my old age). ;-)
Corey Bailey Audio Engineering
On 5/6/2019 8:03 PM, Tim Gillett wrote:
> Hi Corey,
> On a dual capstan deck, the reason it's better for azimuth stability
> is its uniform back tension. In a standard single capstan deck, back
> tension from the supply reel tends to increase as the tape plays from
> start to finish. Changing back tension can change azimuth. An
> interesting complication in our situation is that the deck which
> originally recorded the cassette we are now playing, may not have been
> dual capstan, meaning its recorded azimuth may well change from start
> to end of tape side.
> I was in a team digitising thousands of Oral History cassettes mostly
> recorded on simple single capstan cassette decks. We used Tascam Mk
> III playback machines which, like Naks have a constant back tension,
> but controlled electronically, not by dual capstan. Often the azimuth
> alignment would slowly drift from start to end of the tape side,
> seemingly always in the same direction. If we'd used Naks I suspect
> the result would have been similar.
> Ideally, such tapes would be played in a similar deck with similar
> back tension changes! Or on a model such as a Dragon, but I wonder how
> many of us have access to one of those?
> The other thing is that it's the constant back tension which *allows*
> removal or lifting of the pressure pad. This means that many otherwise
> fine dual capstan cassette decks would potentially benefit from the
> adding of a pressure pad lifter, as per the Naks. I've modded a few
> such dual capstan decks (Pioneer, Tandberg, Sony) with a custom made
> pressure pad lifter with good results. It's not always appreciated
> that the absence of the pressure pad greatly improves head life,
> which is one of the main reasons I like Naks myself.
> The Tascam 122 MkIII retains the pressure pad but it mostly works
> againt the record head, not the play, but has a role to play in
> maintaining the back tension across the play head downstream of it.
> The pressure pad on the record head causes quite a bad wear groove
> after not too long a time, but in even the worst wear cases I've never
> seen a play head - sitting right next to the record head- worn nearly
> as badly or unsalvageable.( The Tascam 122 head is a beautiful piece
> of engineering IMO, which unusually allows full adjustment of the
> record head independently of the play head. They're not locked
> together). In my view the 122 record/play head assembly should be
> replaced not when straight line playback performance suffers, but
> earlier when the record head becomes grooved due to the wear from the
> pressure pad.. This is especially so when azimuth is routinely
> adjusted and the tape is forced to distort inside the "tramline track"
> of the worn record head as the head twists with azimuth adjustments.
> Of course this applies to any tape head in any machine.
> I noticed on a head from a later model Nak deck, relief slots were
> factory cut into the head faces. A nice feature, especially in a
> transfer situation where azimuth is regularly being adjusted.
> Tim Gillett
> Western Australia
> ----- Original Message ----- From: "Corey Bailey"
> <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Monday, May 06, 2019 11:06 AM
> Subject: Re: [ARSCLIST] Tascam 122n MK models
>> Hi John,
>> I prefer cassette decks with a dual capstan mechanism for playback.
>> The reason is that cassettes, particularly old ones, tend to skew and
>> a dual capstan deck will hold azimuth better throughout the length to
>> the tape. Some Nakamichi's also have the added feature of a pressure
>> pad lifter. If you are going to consider a NAK, be sure and buy one
>> that was built post 1982. Dual capstan decks are expensive, even used
>> which, I think, is the only way you will find one. The Tascam that
>> you mention is current but a good used dual capstan machine will out
>> perform it, hands down.
>> My $0.02
>> Corey Bailey Audio Engineering
>> On 5/5/2019 7:19 AM, John Schroth wrote:
>>> Hoping to get some input from everyone.
>>> I'd like to add a Tascam 122 cassette deck to our inventory. I've
>>> been studying up on the different models, reading conflicting
>>> reports. Does anyone have recommendations on which of the models
>>> they prefer - the original 122, MK-II or MK-III?
>>> Thanks in advance for any input.
>>> Kind Regards,
>>> John Schroth
> This email has been checked for viruses by Avast antivirus software.