There's no scientific or electronics design rule limiting a tape machine's frequency response to 10
octaves, that I know of. However, I will speculate that many antique designs may have indeed had
about that limit in practice due to the fact that they used transformers in the circuits, although a
good transformer should be able to pass more bandwidth than that (including good 1950's
transformers). It could also have been a limit of tape-head designs of that time. I can tell you for
a fact that the Plangent Process machine has way more than 10 octaves bandwidth, since the same
heads that recover audio are also recovering bias (to a separate digital track). John Chester or
Jamie Howarth will step in here, but I believe the pathway that reproduces the audio content on the
tape may low-pass somewhere above 20khz so as to not recover ringing, RF or other detrimental noises
that the original recording may have captured.
I will say that all the experiences I've had with the Plangent system, it's recovered the most
content I've heard recovered from old tapes. And, Jamie's process to remove the time-smear
distortions brings the sound quality back closer to the microphones than other playback systems. For
the kind of transfer and remastering work I've done, with classical music content, tape is an
imperfect storage and transmission medium, so anything we can do to remove "the sound of the tape"
is a good thing. This may not be the case for other kinds of music, or for modern settings where
tape is purposely used as a sound effect.
-- Tom Fine
----- Original Message -----
From: "DAVID BURNHAM" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, February 09, 2016 7:13 PM
Subject: Re: [ARSCLIST] Playing reels backwards - separating myth from fact
As far as I know, the frequency response of an analog tape machine depends in large part upon the
head design; ideally, it seems, an analog system has a range of 10 octaves, a situation where the
high frequency limit is 1,000 times the low frequency limit so those old English machines may have
had a range of 18 - 18,000 Hz while more modern machines have a range from 35 - 35,000 Hz. I have
never seen a machine spec that exceeds 10 octaves. I have many recordings done in England in the
late '50s and earlier and on the original LP issues there was substantial information in the 32 foot
range, (16 - 32 Hz), but on the CD reissues those frequencies are completely lacking. This is
obviously most apparent on recordings involving organ, examples: Sargent's first stereo "Messiah",
Boult's recording of Holst's "Choral Symphony", as well as his recording of Elgar's "Dream of
Gerontius", Fruebeck de Bourgous' "Elijah", and Mozart's "Requiem". Those are all EMI recordings; on
Decca you have many recordings from St. John's and King's College which suffer the same loss. It's
frustrating because the digital formats suffer no low frequency restrictions whatsoever.
Disclaimer: I have never seen the machines that were used in England in the late '50s so I'm only
speculating on what may have caused Bass loss on the CD reissues.
On Tuesday, February 9, 2016 4:12 PM, JAMES HOWARTH <[log in to unmask]> wrote:
The same model is inessential. Accurate is accurate, and that has improved. Thanks, Richard for the
kind words on the MLP/Dupré- those are the Plangent electronics and they make no attempt to be
vintage or classic. Nothing rad about the design, other than doing a lot of things right the way we
The reason the old CD issues of the EMI and Decca recordings sound odd is the choices of the
producers, not the Studer. Donahue gets sick results out of an A80/Aria combo, because he’s good.
Wish we could upsell him to a more contemporary package, but it’s still gonna sound like Mark,
faithful to the original.
> On Feb 9, 2016, at 3:33 PM, Dave Burnham <[log in to unmask]> wrote:
> Hi Richard
> Be aware of what I said - that I don't understand the virtue of playing back the tape on the same
> MACHINE, not the same model. I agree that any tape should be played back on a machine with the a
> head and electronics with the same characteristics as the original recorder, though not
> necessarily the same transport; modern transports are smoother than those used 50 or 60 years ago.
> I believe the reason CD issues of EMI and Decca recordings from the 50s and 60s are so bad is that
> they're using modern Studer machines to play back the old tapes instead of the models on which
> they were recorded. Those old machines likely ideally had a frequency response of 18 to 18,000 Hz,
> while the Studers are flat ideally from 30 to 30,000 Hz. You're losing almost an octave of very
> audible material in the bass to gain an octave of largely inaudible material in the highs if
> there's anything there at all.
> Sent from my iPhone
>> On Feb 9, 2016, at 2:30 PM, "Richard L. Hess" <[log in to unmask]> wrote:
>> I recall this topic being discussed with gusto at the end of the last century, and I think the
>> idea should remain there.
>> The reissue of the Mercury Living Presence Marcel Dupré recordings in a new box set is an
>> example, when compared with the early 1990s CD releases, of how modern equipment (both analog and
>> digital) can capture more from the same tapes. The 1990s CDs were very good, overall good or
>> better than the original LPs. The current hi-def files are superb.
>> The same could be said for the RCA Living Stereo CDs and SACDs (I have not experienced the
>> latter) done by Soundmirror/Mark Donahue.
>> I was able to demonstrate that with the Stan Rogers album masters that I made high-res copies of.
>>> On 2/9/2016 1:25 PM, Dave Burnham wrote:
>>> I don't understand the virtue of playing the tape back on the same machine it was recorded on;
>>> any professional machine has separate record and pb electronics and heads so essentially they
>>> are two different machines anyway, except for the transports.
>>> Sent from my iPhone
>> Richard L. Hess email: [log in to unmask]
>> Aurora, Ontario, Canada 647 479 2800
>> Quality tape transfers -- even from hard-to-play tapes.