You'd want to take the digital idea to someone who's expert at modelling plug-ins. Someone like Dave 
Amels (sp?) who designed the Bomb Factory stuff, now he models tube stuff if I recall correctly. 
These guys can take a schematic of a Packburn or any other devise, plug it into their modelling 
software and then tweak the parameters to make the DSP do what the electrical components do to their 
expert satisfaction. Much easier described than done! Whether or not they are successful is up to 
your own ears. I have been very impressed with some DSP stuff and very unimpressed with other. So 
far, no DSP NR except in very small doses has been preferable to my aural aesthetic, but that's just 
one man's opinion. My beef is that digital artifacts, particularly high-end swishes or crackles or 
sizzles, are worse and more annoying than the tape hiss or other background noise being removed. As 
far as impulse-removal, the problem is digital "holes" in the sound, although some of the more 
modern DSP implimentations seem better at this if used with taste and extreme moderation. It all 
depends on how you listen. Play a piano record for a piano player and he likely couldn't care less 
where the piano is sitting in the "air and space" or how close-in it is compared to other 
instruments behind it, he's concentrating on the piano playing. Many but not all superb musicians I 
know -- some members of pretigious symphonies or performing groups -- have what an audio engineer 
would probably consider to be an awful playback system. My point is, all of this stuff is very 
subjective and there's more than one way to do any of it.

The Packburn design is interesting in that part of it is sorta the same concept as the old Scott 
noise-reduction system but Tom Packard told me that they specifically worked around the Scott 
patents in order to gain their own patents. He also told me that he's working on a lower-cost 

Regarding Steve's confirmation that flat-with-gain is the best "diet" to feed a Packburn, this is 
not a hard preamp to create. You can even use a mic preamp if you can bypass the 600-ohm input 
transformer, or more appropriately replace it with something where the cartridge sees 47K-ohms if 
that's what it wants to see. I am not familiar enough with the Packburn to know if it has a 
low-level output to directly feed a phono preamp with EQ.

-- Tom Fine

----- Original Message ----- 
From: "Steven Smolian" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Sunday, March 22, 2009 10:16 AM

> The idea of continual switching to the quieter channel of a mono source is much different from the 
> way Cedar, SF, etc, operate.
> The Packburn works best by a considerable amount if it receives a flat signal.  The more high end 
> it sees, the better it can tell a click from program.  All eq should be added later. That means 
> bypassing the eq in the feed preamp.
> Like much analog equipment, it functions best using more than one pass for extreme cases, 
> resetting parameters a bit each time.    This is true for analog equalizers as well, except it is 
> usually more practical to gang them. The down side is living with the consequences of more than 
> one tape generation
> The Packburn patents have now expired.  It would be interesting to hear this process function in a 
> digital setting.  I discussed this idea with Tom Packard after Dick Burn's memorial service.  At 
> the time he seemed uninterested.  Where does this go from here?
> Steve Smolian
> ----- Original Message ----- 
> From: "Tom Fine" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Sunday, March 22, 2009 7:48 AM
>> One man's opinions here ...
>> I've had pretty good luck with old grooved media (78's and early LP's) as far as ticks and pops 
>> by focusing on deep-cleaning the disks first and foremost. I've been surprised to find that 
>> except for badly damaged disks, 78's are not as prone to constant and annoying ticks and pops as 
>> vinyl. I don't mess with badly damaged disks of either type unless they are highly unique --  
>> usually, given that my time messing with them has a monetary value, it is more cost-effective to 
>> find a better-condition specimen. However, in those few cases where I've had very problematic 
>> disks, as long as I can keep the needle in the groove I still find that, by a very great amount, 
>> the best fix for ticks and pops as far as audibility is the tried and true manually-fix method. 
>> In Sony Soundforge, practice and experience have taught me to zoom in on the ticks and pops and 
>> repaint the waveform using the pencil tool. Practice teaches you how to do this for barely 
>> audible or inaudible results. This is as time-consuming a method as exists except perhaps editing 
>> out microseconds with a blade and splicing tape (done that, hope to never do that again). But, 
>> the results can be superb if you use experience, learning and your ears to shoot for removal with 
>> no new artifacts.
>> As for non-badly-damaged disks, my own taste is to put up with some crackle and a few low-level 
>> ticks and pops. Why try and mitigate what's inherent to the medium? If I make a transfer, of 
>> course I'll go in and manually fix the few big ticks and pops, but not go in and grab every 
>> little disk-noise thing.
>> As far as feeding the Packburn, has anyone tried a flat-with-gain preamplifier, then feed the 
>> output of the Packburn thru an appropriate EQ filter, either as a piece of analog gear or in the 
>> computer? I would think, with no EQ, the Packburn would have the best shot at NR, but I might be 
>> wrong on that. Plan B would be to make sure and use the appropriate phono-preamp curve before the 
>> Packburn, so it is getting the intended frequency spectrum to work on. Then adjust for minimum 
>> artifacts and be satisfied that what you're hearing is as good as you're going to get out of that 
>> chain of equipment and stop worrying about it.
>> But, circling back to my first point, starting with thorough cleaning of the grooved media has 
>> always been my strongest ally in either a good transfer or a pleasant listening experience, or 
>> both.
>> -- Tom Fine
>> ----- Original Message ----- 
>> From: "Jan Myren" <[log in to unmask]>
>> To: <[log in to unmask]>
>> Sent: Sunday, March 22, 2009 4:06 AM
>> HI Again!
>> May it be an idea to take the signal from the Packburn into a paramertic
>> equaliser and try to reduce some of the surface noise that way??
>> Hope to hear from you...
>> Best regards
>> Jan
>> -----Opprinnelig melding-----
>> Fra: Association for Recorded Sound Discussion List
>> [mailto:[log in to unmask]] På vegne av George Brock-Nannestad
>> Sendt: 22. mars 2009 02:44
>> Til: [log in to unmask]
>> From: Patent Tactics, George Brock-Nannestad
>> Hi everybody,
>> Jan Myren described his Packburn setup and seems quite satisfied. I did not
>> know that it had an "undo RIAA" feature in its later versions, but I assure
>> you that the Packburn switcher works even better if the treble is not rolled
>> of like RIAA does.
>> In cooperation with John R.T. Davies Ted Kendall has developed what they
>> used
>> to call "the Mousetrap" that used components that were 25 years younger than
>> those of Packard and Burns, although the basic switcher idea was the same. I
>> do not know whether that is incorporated in Ted's "the Front End"
>> preamplifier that has many useful features. It is only built to order.
>> Jan asked:
>>> BUT; Since I think the Packburn works well on clicks and pops; do you know
>>> if the engineers from the "analogue remaster area" like Robert Parker,
>>> also used a second noise reduction system to get rid of more of that
>> surface
>>> noise, or did they just use it "as is" and accepted a fair amount of
>>> surface noise on their LP-compilations?
>> ----- if I remember correctly, Robert Parker artificially boosted the high
>> frequencies by generating distortion by having an elliptical stylus with the
>> long axis along the groove. This permitted/indeed REQUIRED very heavy treble
>> filtering to remove the distortion (and any noise from 78s), so that he had
>> a
>> lot of fundamentals. Any lack of brilliance was counteracted by heavy
>> reverb.
>> All in all disgusting results, but John R.T. was forgiving: "it will
>> advertise that there is plenty of interesting material in these old records,
>> and those who want to engross themselves will go to the sources".
>>> -----Opprinnelig melding-----
>>> Fra: Association for Recorded Sound Discussion List
>>> [mailto:[log in to unmask]] På vegne av ADRIAN COSENTINI
>>> Sendt: 21. mars 2009 20:13
>>> Til: [log in to unmask]
>>> Emne: Re: [ARSCLIST] PACKBURN 323A
>>> Hi Jan,
>>> When I was the Chief Audio Engineer at The Rodgers & Hammerstein
>>> archives we had a number of Packburns, and we never used them,
>>> because they sounded like shit, to put it mildly. Now a days with all
>>> the digital noise reduction programs out there why aren't you using
>>> that? Also why on earth are you using a RIAA curve on 78's?! You're
>>> missing most of the sound. A KAB pre-amp would be much better, even
>>> though I'm not crazy about the pre-set curves. The OWL 1 is way
>>> better to dial in the curves. Good luck finding one of those. Anyway
>>> toss the Packburn and the RIAA curve.
>>> Adrian
>>> On Mar 21, 2009, at 11:32 AM, Jan Myren wrote:
>>> > About Packburn 323 Audio Noise Suppressor
>>> >
>>> >
>>> >
>>> > HI; I have learned that you for many years (and probably still) use
>>> > the
>>> > Packburn for playback and recording from old 78 rpm discs.
>>> >
>>> > Since I am a collector of old 78's and have a big collection of
>>> > records from
>>> > all ages. I have also spent some recourses on good equipment and I
>>> > think
>>> > this Packburn would be the correct analogue device to my set-up.
>>> >
>>> > I have a Thorens TD 521 turnable. The arm is a SME 3012R and the
>>> > cartridge
>>> > is a Stanton 500MKII and some different stylis, all special made for
>>> > playback of old 78's! I use a normal NAD RIIA preamp.
>>> >
>>> > My experience so far is that it works very well on clicks and pops
>>> > using the
>>> > switcher and the blanker. But the continous noise filter bugs me a
>>> > bit,
>>> > since I think it doesn't reduce that much surface noise. I don't
>>> > use the
>>> > variable adjust very often, since the so called "masked-noise" and the
>>> > pumping effect bring offer "strange noises" to the sound. Therefore
>>> > I mostly
>>> > use the FIXED adjust, and usually set it fixed at 9 o'clock posititon.
>>> >
>>> >
>>> >
>>> > I have read that some re-issue engineers, like Robert Parker used the
>>> > Packburn 323A frequently when restoring old 78's for LP and CD-
>>> > releases.
>>> >
>>> > MY main question is if the Packburn was used as a "stand alone"
>>> > unit or it
>>> > was also supplied with other noise reduction units in order to
>>> > filter out
>>> > more of the surface noise. If so, what did they (or you) actually
>>> > do and
>>> > what could eventually be a good supplement for that purpose?
>>> >
>>> > I would really appreciate if any of you would please give me some
>>> > hints and
>>> > suggestions, since I think the Packburn will work very well if used
>>> > the
>>> > right way!
>>> >
>>> > Really hope to hear from you again!!
>>> >
>>> >
>>> >
>>> > Best regards
>>> >
>>> > Jan Myren¨
>>> >
>>> > NORWAY
>>> >
>>> >