...I'm afraid I haven't experienced this either as long as storage
conditions were decent. My experience, though on a small scale compared with
Goran's, was similar to his. HF record levels had to be critically managed
if the end results of duplication were to be really good. Just my experience
though...
Scott
-----Original Message-----
From: Association for Recorded Sound Discussion List
[mailto:[log in to unmask]] On Behalf Of Shai Drori
Sent: Friday, January 14, 2011 3:20 PM
To: [log in to unmask]
Subject: Re: [ARSCLIST] Association for Recorded Sound Discussion List
<[log in to unmask]>
Same here. Never had a high freq drop on any of my tapes.
Shai
On 1/14/2011 6:43 PM, Goran Finnberg wrote:
> Tom Fine:
>
>> as the cassette naturally
>> loses its level over time.
> Naturally?
>
> Can you give me some hard facts here, Tom.
>
> I have asked this question approx 10 year ago directly via email to
> Jay McKnight an apart from oxide shedding, external magnetic fields,
> magnetized heads there is no known source why the level or treble
> should decrease with time according to him.
>
> Also....
>
> I am asking because during 15 years I was professionally involved in a
> cassette duplicating plant using Gauss, Lyrec, Ampex, King,
> Heino-Ilsemann, Apex, Studer equipment etc.
>
> None of the high speed duplicated cassettes I still have, several 100,
> and none of my approx 60 BASF, Nakamichi and RCA test cassette tapes
> show any change in level or frequency response either objectively or
> subjectively IF the azimuth is very carefully adjusted on my Dragon,
> 582 or 682 Nakamichi decks.
>
> The ONLY thing I´ve seen that changes level is if the replay head is
> not correctly adjusted in height and frequency response above a few
> kHz is directly linked to azimuth and gap loss together with using the
> relevant first orfder gap eq to correct for gap loss above approx 15 kHz.
>
> BTW, professionally duplicating equipment set up correctly, IS capable
> of such good duplicating quality that it will fool 99.9% of all
> listeners in direct A/B test compared to the original sound source. with
ease.
>
> Needless to say the loop bin master must be changed regularly as it
> ages for this to hold true.
>
> So my own experience using magnetic media for some 50 years has not
> turned up any such problem practically.
>
> Even my BASF 15"/38.1 cm/s 35µS CCIR/IEC testtape dated 1968 is within
> 0.1 dB of a few years old MRL G320 nWb/m testtape in its reference
> fluxivity and the frequency response is still within a few 1/10 of a
> dB to 18 kHz when replayed on a flux loop calibrated Studer A820
> despite being used +400 times according to my log.
>
> BASF test tapes were always hot at the high end to the tune of a dB or
> so to offset user losses caused by magnetized heads, guides etc and
> this can still be seen.
>
> BASF test tapes had four repeats of the 1 kHz to 18 kHz bands and
> playing repeat 3 which has only been played two times compared to the
> normal frequency run shows a difference of only 0.3 dB at 18 kHz.
>
> This test tape was recorded on BASF LGR30P red oxide tape.
>
>
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