Dear Richard, Paul and everyone else.
Okay, here's what I think and what made me think about it. The tapes do
not need baking, they do not show any signs on hydrolysis. SKC is a
Koran brand that makes pretty good tapes on the lower end (TDK d, Sony
HF, TDK SA, etc). They can sound very nice and their chrome tapes
reached -1db at 19.5kHz on my auto bias deck. I have never had tapes
from SKC squeal before so I played them in different decks for ingest
and found that they squealed in all decks except the RX-202. This
includes other decks that are single capstan as well.

The RX-202 is a single capstan design that relies on the felt pad for
head contact. I can try to change the shell and slip sheets but I
suspect the tape has dried up a bit. What I think makes it play in the
RX is the head geometry that is more cone like rather than curved. I
think it makes for a shorter head area that is in contact with the tape
and at a sharper angle of attack. The MR-1 (cr-7, dragon, 680, etc, have
more curved heads.

I tried to play the tape in a closed loop (several machines) and it
squealed in all of them. I think the closed loop makes a tighter tape
that resonates faster because of higher tape tension on the head. BTW,
the RX might not be a Dragon but it's a very good player. If I could
only disable it's "skip unrecorded end" where it FF if it thinks there
is nothing recorded, it would be perfect.

Cheers
Shai


בתאריך 06/02/14 9:28 PM, ציטוט Richard L. Hess:
> Hi, Paul,
>
> I'm sorry for all the details, but this was a real gestalt for me.
>
> In general, when a cassette squeals in the Nakamichi Dragon, the only
> thing that helps is lubrication with D5. That was why I was so excited
> by Shai's "discovery" as it provided a whole new perspective on
> potential causes and cures.
>
> Generally (and I'd love to hear Shai's answer with this specific
> tape), placing the tape into a new shell has had no effect. That
> bypasses the slipsheet question and the hub-to-shell friction.
>
> So, thanks to you and others who mentioned slipsheets as that is
> important. I had a cassette that would not play for a client and I was
> able to make it play, and slipsheets were part of the issue--the ones
> that came with the tape were all wavy and horrid. The other part was
> minor layer-to-layer adhesion, but not enough to pull off mag coat.
>
> I do not know what caused the adhesion, but I would not be surprised
> if it were some exudate from the decaying slipsheets.
>
> Cheers,
>
> Richard
>
>
>
> On 2014-02-06 12:20 PM, Paul Stamler wrote:
>> After Richard's detailed discussion I'm hesitant to jump in with an
>> elementary-level question, but here it is:
>>
>> Shai, have you replaced the slipsheets in the squealing cassettes?
>>
>> Peace,
>> Paul
>>
> -- Richard L. Hess email: [log in to unmask] Aurora, Ontario,
> Canada 647 479 2800 http://www.richardhess.com/tape/contact.htm
> Quality tape transfers -- even from hard-to-play tapes.
>

--
Cheers
Shai Drori
Timeless Recordings
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