IIRC this is a known issue with GX tapes.  It’s a breakdown of the
formulation.  The EE variant suffers the most from this.  On the other
hand, their LX tapes which are the most basic tapes hold up well.

On Tue, 8 Nov 2022 at 5:12 Dust Mahrt <[log in to unmask]> wrote:

> As time continues… Quality worsens. The analogue to the digital proves
> that! Before that; reel to album.
>
> Peace,
>
> Dust
>
> PS
> "It's gonna get worse"… Subhumans (UK)
>
> Get Outlook for iOS<https://aka.ms/o0ukef>
> ________________________________
> From: Association for Recorded Sound Discussion List <
> [log in to unmask]> on behalf of Tim Gillett <
> [log in to unmask]>
> Sent: Monday, November 7, 2022 7:21:49 PM
> To: [log in to unmask] <[log in to unmask]>
> Subject: Re: [ARSCLIST] filmy/powdery substance on open reel tape
>
> I noticed this in the late 90's with the same TDK GX tapes recorded
> new in the late 80's.
>
> As you say more of a powdery film. I never did any proper testing but
> recall it didnt seem to induce an audible spacing loss then. Even so
> whenever I played them I regularly cleaned the powder from the tape
> path just to be sure. I still have some of these recorded tapes but
> havent checked them for many years  Maybe these days the problem is
> worse now though?  On yours have you noticed muffled playback after a
> time?
>
> Tim Gillett
>
> Perth,
> Western Australia
>
> ----- Original Message -----
> From: "Association for Recorded Sound Discussion List"
> <[log in to unmask]>
> To:<[log in to unmask]>
> Cc:
> Sent:Mon, 7 Nov 2022 15:01:13 -0500
> Subject:[ARSCLIST] filmy/powdery substance on open reel tape
>
>  Wondering if any of you can help me identify a white filmy/powdery
>  substance on the pack of an open reel tape. At first glance it looks
> like
>  mold but on closer inspection it isn't. There is some kind of
> chemical
>  breakdown happening obviously and the tape is polyester with
>  back treatment. The tape is TDK GX 35/180Bm. There are other tapes in
> the
>  same collection with the same condition but not sure of the brands as
> they
>  are in generic boxes. The only thing in common is that they all are
> back
>  coated.
>
>  Any information on what this is and how to get rid of it will
>  be appreciated.
>
>  --
>  Jonathan
>
> -------------------------
> Email sent using Optus Webmail
>
-- 

Cheers
Shai Drori
Expert digitization services for Audio Video
3K scanning for film 8mm-35mm
Timeless Recordings Music Label
www.audiovideofilm.com
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