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I forgot to mention that I rarely find that side one of a cassette and side two of that same cassette share the same azimuth!!  :-()

Martin

-----Original Message-----
From: Association for Recorded Sound Discussion List <[log in to unmask]> On Behalf Of Martin Fisher
Sent: Thursday, July 25, 2019 11:42 AM
To: [log in to unmask]
Subject: Re: [ARSCLIST] Cassette pressure pads, Nakamichi question and one guy's methods Warning--May be somewhat disjointed

I haven't done exhaustive research into Nakamichi decks but if anyone can either point me to something that describes how the azimuth correction works on these decks (not azimuth theory but how the decks actually do the correction) I would be most grateful.  I'm very wary of equipment that supposes it can do a better job than a discerning ear and even a modicum of common sense along with (and this is most important) caring enough to do it right.  

Here's my cassette transfer work flow.  Feel free to offer suggestions or observations either positive or negative.  That's how we learn.  

Each tape is quickly inspected for obvious trouble (at a glance that is).  This includes ascertaining the condition of the shell and the tape pack.  Is there any contaminant on the tape itself?  Is the pad present and if so is it loose?  If the brand is known to usually exhibit "pad shed" a rather hard whack of each side of the tape shell against my leg usually dislodges any loose pads that would otherwise fall off during transfer.  This can sometimes also loosen up a bound tape pack in the event of an erratic wind.  If the pad is still present but detaches from the spring or is loose I reattach it with a small amount of Super Glue and set aside to cure.  If not I rob a pad and spring from a C-O shell OSRFT and either pop or unscrew the shell and replace the assembly or just move the tape to the new shell.  Usually tapes that use those foam based pads like some Memorex and Scotch variants just get rehoused as a rule.  

(Normally I just set problem tapes aside and work on them during a spare moment.)

Tapes of a specific duration and formulation are usually grouped together to increase efficiency since I do multiple runs at time unless special attention is called for.  

In a spare moment, each tape is wound to the approximate center of side 1 so they are ready to drop into the machines.  The reason for this is that I've noticed that most cassettes exhibit a one direction azimuth "drift" from the beginning of a side to the end of that specific side.  I don’t know the reason for this but it's proven true time and again so I just accept it and make the most of the knowledge.  

My decks of choice are the Tascam 112 variants because they are well built and reasonably quiet.  They have an azimuth nut that is accessible in play mode via a notch in the front panel with the cassette door removed which is much easier to manipulate and less prone to head stripping than a slotted or Philips head screw.  They are also fairly reasonable priced in "needs some attention" condition.  The belts and tires are usually the culprits in most not working situations and these are a relatively easy fix.

Tapes are inserted into decks and proper settings made for specific tape formulation.  Unless NR type is specified I normally assume that none was used unless audition suggests it.  Alignment adjustments are then made for each tape (at the approximate center of the side), tape is rewound to the beginning of side and transfer is started.  This "mid-side" alignment technique IS A COMPROMISE given the aforementioned drift anomaly and is practical ONLY IF THAT ENTIRE SIDE WAS RECORDED FROM BEGINNING TO END ON THE SAME MACHINE.  If it is obvious that sections of the side were recorded on different machines alignment should be performed on each segment after a hard stop/start or on each segment after it is apparent that there was a recording machine switch.  

Alignment can be as anal as you desire as far as I'm concerned.  My mid-side alignment method does a decent job for my purposes although it can't compensate for momentary misalignment that occurs as the tape is settling into the transport path after a cold stop/start during recording.  If it's critical to correct stop/start or constant short term drift, such as temporary physical tape shifting in the transport during recording, this can sometimes be accomplished by monitoring and adjusting "on the fly".  

I usually run four machines going into a single computer interface at once.  This yields four two channel pairs that are each rendered into four two channel files and labeled at the end of a four machine transfer run.  

Martin

Original Message-----
From: Association for Recorded Sound Discussion List <[log in to unmask]> On Behalf Of Tim Gillett
Sent: Thursday, July 25, 2019 5:59 AM
To: [log in to unmask]
Subject: Re: [ARSCLIST] Cassette pressure pads

Hi Chris, When you say the decks dont have azimuth adjusters do you mean no front panel user control, or not even adjusting azimuth screws for a technician? 

Normally I'd expect a reasonable deck to have two screws, one for forward azimuth, the other for reverse azimuth. This is on decks with the one R/P head which rotates through 180 deg when changing from forward to reverse and v/v. If the two angles arent the same, after a while a wear groove can develop on the most used direction (side 1?) and so playing tape on the other side, the tape can become partially lifted out of the wear groove, giving poor response due not only due to azimuth error but also to spacing loss, and possibly shedding, not because of a problem with the tape but because its edges are being damaged on the sharp edge of the head's wear groove.  

Some decks used a full 4 track head and so the head didnt need to move. The change of tracks was achieved by switching electrically. So there was only one azimuth angle and the problem of two different wear patterns on the one head was avoided.

Cheers,
Tim Gillett

----- Original Message -----
From: "Association for Recorded Sound Discussion List"
<[log in to unmask]>
To:<[log in to unmask]>
Cc:
Sent:Thu, 25 Jul 2019 09:54:33 +0100
Subject:Re: [ARSCLIST] Cassette pressure pads

 I have two double auto-reverse decks made by Pioneer and Technics.
 None have pad-lifters. They also do not have azimuth adjusters. The  irritation with these decks is that can I set up two cassettes to play  in sequence and cap. the output with Audacity. However whilst the side  1s play OK, the side 2s are dull and muffled. I then find that the  heads are clogged up and need cleaning.

 So I have a Nak. with pad-lifter and all is well - it plays both of  the cassettes sides quite clearly. BUT its labour intensive requiring  each side of one cassette to be played at a time with manual turnover.
 At least Audacity can continue recording throughout.

 My conclusion is that if cassettes are a tad oldish they will shed and  clog the heads - caused by the pressure pads. Its a pity the pressure  pads can't be simply removed for non-pad-lifter auto-reverse decks.

 BTW I'm only digitising folk music programmes likely aired on AM, or  radio plays. So I'm not too bothered about azimuth adjustments.

 CJB

 P.S. I've heard that folks use PTFE spray (in micro quanitities) to  lubricate the heads and tape path. Would this stop the tape shedding?

 On 25/07/2019, Tim Gillett <[log in to unmask]> wrote:
 > Hi Corey,
 >
 >  I'm aware of a number of non Nak brands such as Sony, Pioneer,  > Sansui, Akai, Tandberg, Revox,  all with  dual capstan mechs, but  > not of any with the lifter.
 >
 > Of course there were a ton of dual capstan decks made, but most of  > them for the purpose of reverse operation without having to flip the  > cassette over.
 >
 > The only non Nak dual capstan decks with a pressure pad lifter that I  > know of  are ones which I've modified myself with a custom made  > lifter.
 >
 > Cheers,
 >
 > Tim
 >
 > ----- Original Message -----
 > From: "Association for Recorded Sound Discussion List"
 > <[log in to unmask]>
 > To:<[log in to unmask]>
 > Cc:
 > Sent:Wed, 24 Jul 2019 20:18:05 -0700
 > Subject:Re: [ARSCLIST] Cassette pressure pads  >  > Tim & Lou:
 >
 > Some of the brands that I'm aware of were Sony, JVC & Technics.
There
 >
 > were others, I'm sure, and I don't have model numbers. There were a  > number of dual capstan decks (a feature that I consider most  > important)  > that may have incorporated pad lifters. There is no database that I  > know  > of that contains this information. Hi Fi Engine is good about listing  >  > the specs of equipment that it has in its database. Anyone with more  > information on this subject should jump in here and perhaps we can  > get a  > database started. What I have noticed is that any of these 20+ year  > old  > machines command prices that are generally too high for me. I have  > spent  > way too much money on decks that wind up dying and the failed part is  >  > now obsolete and not able to be found.
 >
 > Cheers!
 >
 > Corey
 >
 > Corey Bailey Audio Engineering
 > www.baileyzone.net
 >
 > On 7/24/2019 7:40 PM, Tim Gillett wrote:
 > > Hi Corey,
 > >
 > > You said, " FWIW, Nakamichi
 > >
 > > decks weren't the only decks that came with dual capstan transports  > > and  > >  > > pressure pad lifters. Several brands produced audiophile grade  > > machines  > >  > > with dual capstan transports and pressure pad lifters that had  > specs  > > as  > >  > > good as most Nakamichi's."
 > >
 > > I've never come across this. Do you remember which brands  these  > were  > > please?
 > >
 > > Thanks,
 > >
 > > Tim Gillett
 > >
 > > ----- Original Message -----
 > > From:
 > > "Association for Recorded Sound Discussion List"
 > > <[log in to unmask]>
 > >
 > > To:
 > > <[log in to unmask]>
 > > Cc:
 > >
 > > Sent:
 > > Wed, 24 Jul 2019 13:23:43 -0700
 > > Subject:
 > > Re: [ARSCLIST] Cassette pressure pads  > >  > > Hi Martin,  > >  > > I have saved several cassettes that were assembled with screws for  > > those  > > occasions when I have to re-shell a cassette tape. Sometimes, I  > steal  > >  > > just the pads to return the cassette in question to it's best  > > possible  > > condition before transferring the audio.
 > >
 > > Like Lou, I (usually) resort to Nakamichi decks for transfer for a  > > host  > > of reasons. Recently, I transferred several cassette tapes and my  > > beloved Naks wouldn't completely play about half of them. I had to  > > resort to another dual capstan deck for those cassettes. FWIW,  > > Nakamichi  > > decks weren't the only decks that came with dual capstan transports  > > and  > > pressure pad lifters. Several brands produced audiophile grade  > > machines  > > with dual capstan transports and pressure pad lifters that had  > specs  > > as  > > good as most Nakamichi's.
 > >
 > > Cheers!
 > >
 > > Corey
 > >
 > > Corey Bailey Audio Engineering
 > > www.baileyzone.net
 > >
 > > On 7/24/2019 9:42 AM, Lou Judson wrote:
 > > > Martin, I have a few you could have. I use Nakamichi decks for  > > playback so the pressure pads are irrelevant. In a project of some  > > 1500 cassettes to transfer, the guy I work with saved a bunch of  > parts  > > from broken cassettes for repairs, but the pads are useless to me.
 > > Usually all I need for repairs are the hubs with leaders…  > > >  > > > I see only six or seven in the parts box, though. How many do you  > > need? Actually, come to think of it, we are not keeping the  > > transferred cassettes, so I actually have several hundred discards!
 > > >
 > > > Write or call me offlist if this helps. Or get a Nakamichi with  > pad  > > lifters to be better off! :-)  > > >  > > > <L>  > > > Lou Judson  > > > Intuitive Audio  > > > 415-883-2689  > > >  > > >> On Jul 24, 2019, at 9:26 AM, Martin Fisher  > > <[log in to unmask]> wrote:
 > > >>
 > > >> Hey Folks,
 > > >>
 > > >> Does anyone out there have a source for cassette pressure pad  > > assemblies (I say assemblies because the pads are usually attached  > to  > > a spring) or some alternative method of manufacturing your own.
 > I've
 > > tried those peel and stick strips available from several sources  > > online and they just don't cut it. Much too thick and rather  > > cumbersome. Of course I can buy a bunch of C-O shells and mutilate  > > them but I hate to waste so much just for the one part I need most.
 > > >>
 > > >> Thanks! :-)
 > > >>
 > > >> Martin
 > > >>
 > >
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